JPH11284521A - Error correction circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the error rate of data remaining in a pass metric from being affected by a transmission mode after switching at the time of switching transmission modes, when data encoded by one convolutional encoder is continuously subjected to Viterbi decoding, exceeding different modulation multivalued numbers. SOLUTION: A Viterbi decoder control circuit recognizes the switching timing of transmission modes A→B, turns on a switching control signal from the point of time (J), when the last symbol of the mode A is inputted to a pass memory until the point of time (1), when it is outputted and outputs it is an ACS circuit. While the switching control is on, the ACS circuit refers to the minimum path metric decision result of the last symbol of the mode A and outputs a Viterbi decoding symbol of the mode A from the path memory. The switching control signal is turned off after the point of time, when the entire path memory is filled with the mode B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an error correction circuit for performing error correction encoding and decoding digitally transmitted data.

[0002]

2. Description of the Related Art In recent years, in Japan, Europe and the United States, digitization of TV broadcasting has been rapidly progressing for each of media such as cable, satellite and terrestrial broadcasting. In Japan, digital CA
The standard TV system was published in the official gazette at the end of 1996, and standard broadcasting is being studied with the aim of starting terrestrial broadcasting around 2000. On the other hand, for satellite broadcasting, C
S (Communication Satellite) digital broadcasting is 199
The standard broadcasting system has been studied by the Telecommunications Technology Council and the Radio Industry Association with the aim of starting broadcasting in 2000.

[0003] In BS digital broadcasting,
Since the power of the transponder is twice as large as that of CS digital broadcasting, TC-8PSK (Trellis
The adoption of Coded-8-ary Phase Shift Keying (trellis-coded 8-phase PSK) is being studied. As a result, a larger transmission capacity can be obtained than in CS digital broadcasting employing QPSK (Quarternary PSK: four-phase PSK), and a HDTV (High Definit
ion TV) can be transmitted in two channels. Or HDTV
SDTV (Standard Definitio)
n TV) for 3 channels. However, since the number of modulation levels (the number of phases) is large and the distance between codes is small, the service time rate is reduced due to rainfall attenuation, that is, the unviewable time is increased to some extent.

As a countermeasure, the adoption of hierarchical transmission is being studied (Kato et al .: "Study of Satellite ISDB System", Technical Report of the Institute of Image Information and Television Engineers, BCS97-12 (Mar. 1997)).
). This is because the high-resolution video (high hierarchy) is TC-8P
SK is transmitted, and an image (low hierarchy) of the same content and reduced to a low bit rate is QPSK or BPS.
In K (Binary PSK: two-phase PSK), transmission is performed by time-division multiplexing in the same transmission frame as a higher layer. On the receiver side, all the modulated data (TC-8P
SK, QPSK, and BPSK) are demodulated by PSK, and in a normal state, a high-layer image of TC-8PSK is MPEG-decoded and the image is output to a monitor. On the other hand, the C / N ratio (Ca
rrier to Noise ratio), QPSK
MPEG decoding of a low-layer image of BPSK or BPSK and outputting the image to a monitor.

[0005] By performing such hierarchical transmission,
Although the image has a low resolution during heavy rain, it is possible to prevent the service time rate from decreasing. The standard system of BS digital broadcasting currently under discussion will be described below with reference to the drawings.

FIG. 76 shows an error correction coding apparatus 10 on the transmission side.
001 is a block diagram showing an example of the configuration of FIG. The error correction coding apparatus 10001 shown in FIG.
2, an RS (Reed-Solomon) encoding circuit 10003,
Randomizing circuit 10004 and interleaving circuit 1
0005, a byte / symbol conversion circuit 10006,
Convolutional encoder 10007 and mapping circuit 10
008 and a transmission control information generation circuit 10009.

The error correction coding apparatus 10 having such a configuration
The operation of 001 will be described. Multiple types of MPEG transport streams (TS: Transport Stream)
Is input to the error correction coding apparatus 10001 and TS
The multiplexing circuit 10002 multiplexes a plurality of types of TS, and
A multiplexed TS is generated as shown in (a) (in this case, two types of TS are assumed).

[0008] Such a multi-TS multiplexing system provides a physical independence of each broadcaster, so that each broadcaster has a different TS.
And multiplexing within a frame. In other words, in CS digital broadcasting, one transponder has one TS, but in BS digital broadcasting, one transponder can include a plurality of TSs (up to eight).

The RS encoding circuit 10003 shown in FIG. 76 converts the data series shown in FIG.
188), and a parity of 16 bytes is added to 188 bytes of MPEG TS.
The data is output as a data series as shown in FIG. A 48 MPEG packet is defined as one frame, and eight frames are defined as one superframe. The randomizing circuit 10004 is shown in FIG.
For the data series of (b), one superframe (4
Randomization is performed at a cycle of (8 MPEG packets × 8 frames), and output to the interleave circuit 10005.
As shown in FIG. 77 (c), the randomizing circuit 1000
The PN generator in 4 is reset at the second byte of the first frame of each superframe, and performs multiplication of input data using a generator polynomial. However, each MPEG packet 20
4 bytes first byte (MPEG synchronization byte: 47h)
During the period, the PN generator is in a free-run state and does not multiply data.

[0010] In addition, PN (Pseudo-r
Andom Noise) sequence, the generating polynomial as 1 + x ¹⁴ + x ^15, the initial value (100,101,010,000,000).

FIG. 77 (d) is a structural diagram of a transmission frame. The 204 bytes after randomization are one slot, one frame is composed of 48 slots, and one superframe is composed of eight frames. The first byte of each slot is
After interleaving, it is replaced with transmission control information including various information of a superframe.

[0012] The randomized data sequence is interleaved in an interleave circuit 10005,
Output to the byte / symbol conversion circuit 10006. Interleaving is performed by excluding the first byte of each slot.
For 3 bytes, a block of depth 8 per slot
Interleaving is performed for 48 slots. That is, FIG.
As shown in FIG. And a depth of 8 in the superframe direction for each slot
Block interleaving is performed. Next, the ith slots of the first to eighth frames are collectively interleaved and returned to the ith slot every 1/8 (1 ≦ i ≦ 4
8).

The above-described interleaving is performed. Here, when the actual read address value for the i-th slot is indicated (the number indicates a frame-byte), the following is obtained. Start 2nd Byte 203th Byte First Frame: 1-1 2-1 ... 3-26 Second Frame: 4-26 5-26 ... 6-51 Third Frame: 7-51 8-51 ... 1-77 Fourth frame: 2-77 3-77 ... 4-102 Fifth frame: 5-102 6-102 ... 7-127 Sixth frame: 8-127 1-128 ... 2- 153 7th frame: 3-153 4-153 ... 5-178 8th frame: 6-178 7-178 ... 8-203 For example, the access order of the first frame is described in detail as follows. . 1-1,2-1,3-1, ... 8-1 1-2,2-2,3-2, ... 8-2 ... 24,2- 24, 3-24, ... 8-24 1-25, 2-25, 3-25, ... 8-25 1-26, 2-26, 3-26

As described above, the interleave circuit 100
At 05, block interleaving with a depth of 8 is performed for 48 slots in slot units. Assuming that the coding rate is r, as described above, TC-8PSK (r = ２), QPSK,
(R = 3/4, 1/2) and BPSK (r = 1/2) data. One frame is composed of 48 slots, and one superframe is composed of 48 × 8 slots. When all the slots are transmitted by TC-8PSK (r = 2/3), the data of 48 slots is transmitted as a whole. It is possible. On the other hand, QPSK (r = 3/4), QPSK (r
= １ ／), BPSK (r = １ ／) is TC-8PS
K (r = 2/3), the transmission efficiency is 3 /
4, 1/2, 1/4.

Since the transmission time of one superframe is constant, QPSK (r = 1/1) as shown in FIG.
In the case of transmitting the slot of 2), one slot per two slots is used as a dummy slot for the interleave circuit 1.
[0005] At the time of output, only one effective slot per two slots is output at the time of input.
/ 2. Similarly, FIG.
As shown in (b) and (c), QPSK (r = 3/4)
Is 1 slot per 4 slots, BPSK (r = 1 /
In 2), 3 slots out of 4 slots are dummy
It becomes a slot.

As described above, the first byte (MPEG synchronization byte: 47h) of each slot is interleaved, and thereafter, transmission control information (TMCC: Transmission Multiplexing Configuration) including various information of a superframe.
n Control). FIG. 80 shows a configuration example of the transmission control information generation circuit 10009. As shown in the figure, the transmission control information generation circuit 10009 includes a control information generation unit 10010, an RS encoding circuit 10011, a TAB
Signal insertion unit 10012 and randomizing circuit 10013
And

TMCC is 48 slots × 8 frames =
It is generated in superframe units by replacing the 384 bytes obtained by collecting the first byte of each slot in the 384 slots for one superframe. Since TMCC is important information, the BPS at the beginning of each frame precedes the main signal.
Transmission is performed at K (r = １ ／). Therefore, since the transmission efficiency is 1/4 of TC-8PSK (r = 2/3),
The data actually transmitted is 96 bytes (= 384 bytes / 4).

The operation of the transmission control information generation circuit 10009 will be described below. In FIG. 80, control information generation unit 10
010 generates 48 bytes of TMCC as transmission control information of the next superframe,
011. The control information generation unit 10010 converts the modulation parameter into the byte / symbol conversion circuit 10 shown in FIG.
006, output to the convolutional encoder 10007 and the mapping circuit 10008.

FIG. 81 shows an example of the contents of 48 bytes (384 bits) of TMCC. In BS digital broadcasting, a transmission frame configuration of 48 slots, that is, one superframe = 8 frames, is employed in order to allow a plurality of TSs to be used in one modulated wave and to enable operation switching of a plurality of modulation schemes by a broadcaster. . These are control information newly added for broadcasting to the control information of MPEG2 System. It is necessary to transmit such transmission control information (TMCC) as information for clarifying the transmission mode of each slot and the relationship with the TS. In addition, TMCC
Since is also a signal for transmitting information related to modulation and demodulation, information related to transmission / reception control is included here. FIG.
In 1, the version information instructs to change the content of the TMCC, and is incremented by one each time the content is changed, for example. By monitoring this information, the receiver can recognize the timing of changing the contents of TMCC.

FIG. 82 shows an example of the configuration of the transmission mode / slot information. The transmission mode is an item indicating a combination of a modulation scheme to be used and an inner code (convolutional code). In the figure, the number of allocated slots indicates the number of slots per frame allocated to the immediately preceding transmission mode (including the dummy slots described above). The transmission mode that is not used is identified by the fact that the number of assigned slots immediately after is 0. In the main signal, as shown in FIG. 82, the slots are arranged in the slots in the order of the transmission mode of the modulation scheme having a large number of phases and the inner coding scheme having a high coding rate.

FIG. 83 shows an example of the structure of relative TS / slot information. In order to transmit a plurality of TSs in one modulated wave, it is necessary to clearly indicate in which slot in the transmission frame each TS is located. Since the TS_ID used in the MPEG2 System is 16 bits, it is not preferable to use it as it is in terms of transmission efficiency. Instead, the TS transmitted in each slot is indicated for each slot in order from slot 1 by using the relative TS number based on the 3-bit relative TS / slot information. Relative T
By setting the S number to 3 bits, a maximum of 8 TSs can be transmitted in one modulated wave.

FIG. 84 shows an example of the structure of the relative TS / TS correspondence table. By having a correspondence table of TS_ID (16 bits) for each relative TS number, the use of the relative TS number is completed only by the modem.

FIGS. 85 and 86 show examples of the structures of transmission / reception control information and extension information, respectively. In the transmission / reception control information, a signal for controlling the activation of the receiver in the emergency alert broadcast and a control signal for switching the uplink station are transmitted.
The extension information is a field used for future TMCC extension.

When 48 bytes of TMCC shown above are output from the control information generation unit 10010 in FIG. 80, the RS encoding circuit 10011 encodes RS (64, 48), and generates a 16-byte parity for 48 bytes of TMCC. Is added and output. The TAB signal insertion unit 10012
As shown in FIG. 87, the RS-encoded 64-byte data sequence is divided into eight frames each,
A TAB signal of 2 bytes is inserted before and after each byte, and a TMCC of 96 bytes per superframe (12 bytes per frame) is transmitted to the randomizing circuit 10.
013. Here, of the TAB signals, W1 (=
1B95h) is for frame synchronization, and W2 (= A340h) is for superframe identification. In the following description of the TAB signal, a signal before convolutional coding is denoted by a capital letter W, and a signal after convolutional coding is denoted by a small letter w.

The randomizing circuit 10013 shown in FIG.
The data sequence output from the TAB signal insertion unit 10012 is randomized at a period of one superframe of TMCC (96 bytes) and output to the byte / symbol conversion circuit 10006 in FIG. As shown in FIG. 88, the PN generator of the randomizing circuit 10004 is reset at the third byte of the first frame of each superframe, and multiplies with the input data. However, the data is not multiplied as a free run during the period of each TAB signal (W1, W2, W3).

As described above, the transmission control information generation circuit 10
009 is a 96 byte TM per superframe
The CC is output to the byte / symbol conversion circuit 10006, and the modulation parameters (the number of phases and the coding rate) of the data sequence in the superframe are converted to the byte / symbol conversion circuit 10006 and the convolutional encoder 1000 in FIG.
7 and the mapping circuit 10008.

FIG. 87 shows a 12-byte TMCC per frame output from the transmission control information generation circuit 10009 and a 203 × 48-byte main signal in TC-8PSK conversion per frame output from the interleave circuit 10005 shown in FIG. The data is input to the byte / symbol conversion circuit 10006 in a superframe structure. That is, the first 12 bytes of each frame are TMCC, and the next 203 × 4
Eight bytes are a main signal, and eight frames are collected to form a superframe. As shown in FIG. 89,
In each frame, the main signal is arranged in ascending order of modulation multilevel number (phase number). However, the QPSKs are arranged in descending order of the coding rate, such as the coding rate r = 3/4 → r = 1/2.

The byte / symbol conversion circuit 10006 includes:
According to the modulation parameter output from the transmission control information generation circuit 10009, the input byte data sequence having the superframe structure is converted into a phase number and a phase number as shown in FIG.
The data is converted into a symbol data sequence corresponding to the coding rate. Note that the symbol output shown in FIG. 90 is TC-8PSK (r =
2/3) is parallel 2 bits, QPSK (r = 3/4, 1 /
2), BPSK (r = 1/2) is 1 bit.

The symbol data sequence having the superframe structure output from the byte / symbol conversion circuit 10006 is input to the convolutional encoder 10007. FIG.
FIG. 1 is a block diagram showing a configuration example of a convolutional encoder 10007. This convolutional encoder 10007 is:
It comprises a convolution circuit 10014 indicated by a dotted line and a punctured P / S (Parallel to Serial) circuit 10015.

When the symbol data sequence D [2: 1] is input to the convolution circuit 10014, the convolution circuit 10014
Reference numeral 14 denotes LSB D [1] = D1 with a constraint length of 7, an encoding rate of 1 /
2 to perform convolutional coding to obtain a 2-bit symbol C
1, and C0 are output to the punctured P / S circuit 10015. Further, D [2] = D of the MSB of the symbol data series
For C.2, C2 that is the MSB of the coded symbol (C2, C1, C0) is output to the punctured P / S circuit 10015 without performing convolutional coding.

The punctured P / S circuit 10015
According to the modulation parameters output from the transmission control information generation circuit 10009, punctured processing and P / S conversion are performed as shown in FIGS. 92 to 95, and encoded symbol data corresponding to each phase number / coding rate is obtained. Mapping circuit 10
008. However, TC-8PSK (r = 2 /
3) and QPSK (r = 1/2) do nothing. As described above, one convolution circuit 10014 continuously performs convolutional encoding of a symbol data sequence over different modulation schemes (number of phases) and coding rates.

FIG. 92 shows an operation example in the case of TC-8PSK (r = 2/3). In this case, the convolutional encoder 1
The symbol data D [2: 1] input to the 0007 is LS
D [1] of B is subjected to convolutional encoding by a convolution circuit 10014 to become 2-bit encoded symbols C1 and C0. D [2] of the MSB is C2 of the MSB of the coded symbol without being subjected to convolutional coding. These symbols C0 to C2 are output to punctured P / S circuit 10015. Punctured P / S circuit 10015
One symbol = 3 bits of 8PSK symbol data C2, C1, C0 is mapped without any processing to the mapping circuit 1000.
8 is output. In this case, the convolutional encoder 1000
7, one symbol (2 bits) input is encoded,
One symbol (3 bits) is output. Therefore, the coding rate of the entire convolutional encoder 10007 is r = 2.
/ 3.

FIG. 93 shows an operation example in the case of QPSK (r = 3/4). The symbol data D [2: 1] (where D [2] of the MSB is invalid) input to the convolutional encoder 10007 is obtained by converting the LSB D [1] into a convolution circuit 10014.
Is subjected to convolutional encoding to become two bits C1 and C0, which are output to the punctured P / S circuit 10015. In the punctured P / S circuit 10015, as shown in FIG. 93, 2 bits are regularly discarded from 3 symbols = 6 bits of data, that is, punctured, and 1 symbol = 2 bits from the remaining 4 bits of data. Bit QPS
K symbol data C1 and C0 are generated and output to mapping circuit 10008. The MSB symbol C2 is invalidated. In this case, 3 symbols (3 bits) input to the convolutional encoder 10007 are encoded, and 2 symbols (4 bits) are output. Therefore, the coding rate of the entire convolutional encoder 10007 is r = 3/4.

FIG. 94 shows an example of operation in the case of QPSK (r = 1/2). The symbol data D [2: 1] (where D [2] of the MSB is invalid) input to the convolutional encoder 10007 is obtained by converting the LSB D [1] into a convolution circuit 10014.
Is subjected to convolutional encoding to become two bits C1 and C0, and output to the punctured P / S circuit 10015. Punctured P / S circuit 10015 outputs 1 symbol = 2 bits of QPSK symbol data C1 and C0 to mapping circuit 10008 without any processing.
However, the symbol C2 of the MSB is invalidated. In this case, one symbol (1 bit) input to the convolutional encoder 10007 is encoded, and one symbol (2 bits) is output. Therefore, the coding rate of the entire convolutional encoder 10007 is r = １ ／.

FIG. 95 shows an operation example in the case of BPSK (r =＝). The symbol data D [2: 1] (where D [2] of the MSB is invalid) input to the convolutional encoder 10007 is obtained by converting the LSB D [1] into a convolution circuit 10014.
Is subjected to convolutional encoding to become two bits C1 and C0, which are output to the punctured P / S circuit 10015. As shown in FIG. 95, the punctured P / S circuit 10015 performs a 2-bit P / S conversion of each symbol C1 and C0, and one symbol = 1 bit B in the order of C0 → C1.
The PSK symbol data (C0 / C1) is output to the mapping circuit 10008. However, two bits are invalidated from the MSB. In this case, one symbol (1 bit) input to the convolutional encoder 10007 is encoded, and two symbols (2 bits) are output. Therefore, the coding rate of the entire convolutional encoder 10007 is r = １ ／.

As shown in FIGS. 92 to 95, the symbol data output from the convolutional encoder 10007 is:
The mapping circuit 1000 of FIG. 76 at a constant symbol rate
8 is output. As shown in FIG. 96, mapping circuit 10008 controls the BPSK, QPSK,
TC-8PSK mapping is performed, and the mapped I (In-Phase) axis and Q (Quadrature Phase) axis data are output to a quadrature modulator (not shown).

The error correction coding apparatus 100 described above
FIG. 97 shows the flow of signals from the input to the output of No. 01 per frame. Here, TS1
And two types of TSs, TS2 and TS2, are transmitted by one modulated wave. For one frame (48 slots), TS1: <high-layer image> TC-8PSK: 22 slots <low-layer image> QPSK (r = 1/2): 2 slots (including 1 dummy slot) TS2: <high-layer image> TC-8PSK: 20 slots <low-layer image> BPSK (r = 1/2): 4 slots (including 3 dummy) Slot).

TS1 and TS2 as shown in FIG.
Is input to the error correction coding apparatus 10001 in FIG. 76, the TS multiplexing circuit 10002 multiplexes two TSs. Then, the RS encoding circuit 10003 converts the RS (204,
188) Perform encoding. And the randomizing circuit 100
Reference numeral 04 performs randomization, and outputs a data sequence of 48 slots (1 slot = 204 bytes) per frame as shown in FIG. 97 (b). However, of the 48 slots, four hatched slots are dummy slots. Here, the data sequences are arranged in descending order of the modulation multi-level number (the number of phases), and the coding rate r = 3/4 → QPSK.
Arrange from the higher coding rate such as r = 1/2.

The interleave circuit 10005 calculates the first byte (MPEG synchronization byte: 47h) of each slot.
As for the 203 bytes excluding the above, block interleaving with a depth of 8 is performed in the superframe direction for each slot as described above. Further, the transmission control information generation circuit 100
09 generates a TMCC and replaces it with the MPEG synchronization byte: 47h, which is the first byte of each slot. As a result, as shown in FIG. 97 (c), the byte / symbol conversion circuit 10006 includes a byte data sequence composed of a main signal of 203 bytes × 44 slots following 12 bytes of TMCC including a TAB signal for each frame. Is entered.

The byte / symbol conversion circuit 10006 comprises:
The input byte data sequence is converted into a symbol data sequence corresponding to the transmission mode (phase number / coding rate) of each slot. The convolutional encoder 10007 performs convolutional encoding corresponding to the transmission mode of each slot.
Further, the mapping circuit 10008 performs mapping according to the number of phases of each slot, and outputs a data sequence shown in FIG. 97 (d) to a quadrature modulator (not shown). FIG. 97
As shown in (d), 12 bytes of TMCC, that is, 96 bits per frame are subjected to BPSK (r = 1/2) encoding, so that 192 symbols (1 symbol = 1) are used.
Bit).

In the main signal, TC-8PSK 1
The slot (203 bytes), that is, 1624 bits, becomes 812 symbols (1 symbol = 3 bits) as a result of encoding. 1 slot of QPSK (r = 1/2) (203 bytes: 2 slots including dummy), that is, 1624
The bits become 1624 symbols (1 symbol = 2 bits) as a result of encoding. One slot (203 bytes: 4 slots including dummy) of BPSK (r = １ ／), that is, 1624 bits, becomes 3248 symbols (1 symbol = 1 bit) as a result of encoding. From the above, one frame is composed of 192 symbols of TMCC and 38976 of main signal.
It consists of symbols (812 × 48).

Next, the error correction coding apparatus 1 described above
A circuit that performs error correction decoding on a data sequence that has been subjected to error correction encoding in 0001 will be described below with reference to the drawings as an error correction circuit that has been studied so far (hereinafter, referred to as a conventional error correction circuit). .

FIG. 98 shows a conventional error correction circuit 20001.
FIG. 3 is a block diagram illustrating a configuration example of FIG. This error correction circuit 2
0001 is a Viterbi decoder 20002, a high / low hierarchy selection signal generation circuit 20003, a symbol / byte conversion circuit 20004, and a de-interleave circuit 20005.
And MPEG synchronization byte / dummy slot insertion circuit 2
0006, de-randomizing circuit 20007, and RS
Decoding circuit 200008, speed conversion circuit 200009, transmission control information decoding circuit 20090, tuning circuit 20011
And

The error correction circuit 20001 having such a configuration is described.
The operation of will be described below. The data sequence error-correction-coded by the error-correction coding apparatus 10001 of FIG. 76 is quadrature-modulated by a quadrature modulator (not shown), and transmitted through a satellite transmission path including a transponder. This signal is PSK demodulated by a PSK demodulator on the receiving side (not shown). The constraint length of the convolution circuit 10014 described with reference to FIG. 91 is 7, and the TAB signal section is transmitted by BPSK.
Therefore, the TAB signal (w1, w2, w
3) has 32 symbols (1) as shown in FIG.
Of the 6 × 2 = 32 bits, the first 12 symbols (6 bits × 2) are indeterminate. However, the remaining 32-12 =
20 symbols are w1 (= xxxECD28h), w2 (= xxx0B6
77h) or w3 (= xxxF4988h). When the tuning is switched by the tuning information, the PSK demodulator first performs demodulation by delay detection, and performs w1, w2,
By detecting w3, the superframe synchronization and the absolute phase are detected. After detection, synchronous detection is performed and PSK
The demodulated data and the superframe synchronization signal are output to the error correction circuit 20001.

The transmission control information decoding circuit 20010 in the error correction circuit 20001 uses the superframe synchronization signal output from the PSK demodulator to
A control signal (transmission mode) is generated for the 192 symbol section and output to Viterbi decoder 20002. The Viterbi decoder 20002 calculates the T of each frame shown in FIG.
For the MCC192 symbol section, B
PSK (r = １ ／) Viterbi decoding is performed. And 19
It outputs Viterbi decoded data of 2 symbols × １ ／ = 96 symbols (96 bits) to the transmission control information decoding circuit 20010. The details of the Viterbi decoder 20002 will be described later.

FIG. 99 shows a configuration example of the transmission control information decoding circuit 20010. This transmission control information decoding circuit 20010
Are a de-randomizing circuit 20012, a symbol / byte conversion circuit 20013, and an RS decoding circuit 20004.
And a TMCC decryption circuit 20005.

In the transmission control information decoding circuit 20010, the de-randomizing circuit 20012
2 and 96 symbols per frame (96
Bits), that is, 768 bits (96 bytes) of TMCC per superframe, as shown in FIG.
Data is cycled at a cycle of CC1 superframe (96 bytes).
Randomizes the symbol / byte conversion circuit 200
13 is output. As shown in FIG. 88, the PN generator in the de-randomizing circuit 20012 is reset at the third byte of the first frame for each superframe, as in the randomizing circuit 10004 in FIG. Done. However, each TAB signal (W1, W2,
During the period of W3), the PN generator is in a free run, and the data is not multiplied.

The symbol / byte conversion circuit 200 shown in FIG.
13 converts the input data sequence of 768 symbols (768 bits) per superframe into a byte data sequence of 96 bytes and outputs it to the RS decoding circuit 20004. As shown in FIG. 87, in the 12 bytes of each frame, the TAB signal (W1 and W2 or W3) is included before and after 2 bytes, so that the net TMCC signal is 8 bytes per frame (64 bytes per superframe). ). The RS decoding circuit 20004 in FIG. 99 converts the RSTM (64, 4
8) is decoded, and the 48-byte corrected TMCC is
Output to the MCC decoding circuit 20005.

A TMCC decoding circuit 20055 decodes the contents of the corrected 48-byte TMCC with reference to the signal arrangement diagrams shown in FIGS. 81 to 86, and outputs various transmission control information such as a transmission mode and dummy slot information. Then, reference is made to the MPEG TS_ID and the relative TS number. As described above, the TMCC decoded in the transmission control information decoding circuit 20010 is various transmission control information applied to the next superframe. As shown in FIG. 87,
The TMCC is arranged at the head of the first to eighth frames in the super frame. Transmission control information decoding circuit 20010
The decoding of the TMCC is not completed until the TMCC (parity 2) of the eighth frame is input to the. However, as shown in FIG. 87, the main signal of the eighth frame is TC-
As shown in FIG. 97 (d), there are 812 × 48 symbols in terms of 8PSK conversion and 203 × 48 bytes in symbol, and there is a time margin for one superframe.
In this period, the decoding of the TMCC can be sufficiently completed.

Now, when the symbol data sequence (I / Q axis) of the superframe structure outputted from the PSK demodulator is inputted to the Viterbi decoder 20002, the Viterbi decoder 20002
0002 performs Viterbi decoding and outputs decoded data to a high / low hierarchical selection signal generation circuit 20003 and a symbol / byte conversion circuit 20004.

FIG. 100 shows a Viterbi decoder 20002 and a high /
FIG. 18 is a block diagram illustrating a configuration example of a lower hierarchy selection signal generation circuit 20003. Viterbi decoder 2000 indicated by lower broken line
2 is de punctured S / P (Serial to Paralle)
l) It has a circuit 2016 and a Viterbi decoding circuit 20017 indicated by a dotted line. Viterbi decoding circuit 2001
7 is a branch metric calculation circuit 20008, and ACS
(Add, Compare, Select) circuit 20019, path metric memory 2008, and path memory 20021
And The high / low hierarchy selection signal generation circuit 20003 indicated by the upper broken line is an 8PSK hard decision circuit 200.
22, BER (Bit Erro)
r Rate) measurement circuit 20024 and convolution circuit 200
25.

When a PSK demodulated symbol data sequence (I / Q axis) is input to Viterbi decoder 20002, depunctured S / P circuit 20060 determines the transmission mode output from transmission control information decoding circuit 20010 according to the transmission mode. As shown in FIG. 101 to FIG. 104, depuncture processing and S / P conversion corresponding to the transmission mode of each slot are performed and output to the Viterbi decoding circuit 20017. The de-punctured data and S / P converted data are shown in FIG.
According to the transmission mode output from the transmission control information decoding circuit 20010, the Viterbi decoding circuit 20017 performs Viterbi decoding corresponding to the transmission mode of each slot. Then, the Viterbi decoded symbol is output to the symbol / byte conversion circuit 20004. Error correction encoding device 10
Since the convolution coding in 001 is continuously performed by one convolution circuit 10014 as shown in FIG. 91, the Viterbi decoding in the error correction circuit 20001 of FIG. 98 is continuously performed by one Viterbi decoder 20002. Decryptable.

FIG. 101 shows TC-8PSK (r = 2/3)
FIG. 35 is an explanatory diagram showing an example of a decoding operation in the case of. The 8PSK demodulated symbol data (I / Q axis) input to the Viterbi decoder 20002 is converted to a depunctured S / P circuit 200.
16, no processing is performed, and the Viterbi decoding circuit 2001
7 as it is. Viterbi decoding circuit 20007
Then, the branch metric calculation circuit 20008
A branch metric with eight code points of 8PSK shown in FIG. 6, for example, a Euclidean distance is calculated. Based on the branch metric calculated here, the ACS circuit 2001
9, Viterbi decoding is performed by the path metric memory 20082 and the path memory 20021. Then, 1 symbol = 2 bit Viterbi decoded symbol (D in FIG. 92)
[2: 1] is output to the symbol / byte conversion circuit 20004 in FIG.

FIG. 102 is an explanatory diagram showing an example of a decoding operation in the case of QPSK (r = 3/4). Viterbi decoder 200
02 QPSK demodulated symbol data (I / Q
When the axis) is input to the depunctured S / P circuit 20066, the punctured P / S circuit 100 in FIG.
The de-punctured S / P circuit 20060 inserts a null symbol into the symbol that has been punctured and discarded at 15, and converts two symbols into three symbols. Note that a null symbol is an intermediate value between two types of code points obtained on the Q axis or an intermediate value between two types of code points obtained on the I axis. These symbols are output to Viterbi decoding circuit 20017 in FIG. In the Viterbi decoding circuit 20017, the branch metric calculation circuit 20
018 calculates a branch metric with the four code points of QPSK shown in FIG. Then, based on the calculated branch metric, Viterbi decoding is performed by the ACS circuit 20019, the path metric memory 20080, and the path memory 20021. Thus, one symbol = 1
Bit Viterbi decoded symbol (corresponding to D [1] in FIG. 93:
D [2] of the MSB is invalid) is output to the symbol / byte conversion circuit 20004 of FIG.

FIG. 103 is an explanatory diagram showing an example of a decoding operation in the case of QPSK (r = １ ／). Viterbi decoder 200
02 QPSK demodulated symbol data (I / Q
The axis is output to the Viterbi decoding circuit 20017 without any processing in the depunctured S / P circuit 2006. In the Viterbi decoding circuit 20017, the branch metric calculation circuit 20018 calculates the branch metric with the four code points of QPSK shown in FIG. Then, based on the calculated branch metric, A
CS circuit 20019, path metric memory 2002
0 and the path memory 22021 perform Viterbi decoding. In this way, one symbol = 1 bit Viterbi decoded symbol (corresponding to D [1] in FIG. 94 and D [2] of the MSB being invalid) is converted to the symbol / byte conversion circuit 20 in FIG.
004 is output.

FIG. 104 is an explanatory diagram showing an example of a decoding operation in the case of BPSK (r = 1/2). Viterbi decoder 200
02, the I-axis (Q-axis data is invalid) of the BPSK demodulated symbol data is input to the depunctured S / P circuit 20066 every two input symbols (I, Q).
The symbol is subjected to S / P conversion and output to the Viterbi decoding circuit 20017. Viterbi decoding circuit 20007
Then, the branch metric calculation circuit 20008
A branch metric with the four code points of QPSK shown in FIG. 6 is calculated. Then, based on the calculated branch metric, the ACS circuit 20019 and the path metric memory 2
The Viterbi decoding is performed by the 0020 and the path memory 20021. Thus, 1 symbol = 1 bit Viterbi decoded symbol (corresponding to D [1] in FIG.
[2] is invalid), but the symbol / byte conversion circuit 20
004 is output.

FIG. 105 shows TC-8PSK (r = 2/3)
FIG. 21 is a trellis diagram showing the operation of the Viterbi decoding circuit 20017 in the case of FIG. As shown in FIG. 91, D [2] (= D2) of the MSB is not encoded in the convolutional encoder 10007 of the error correction encoding apparatus 10001.
Therefore, D [2: 1] = (0,0) and (1,0) as (D2, D1), and (0,1) and (1,1) as D [2: 1].
Are considered the same in the trellis diagram of FIG. Therefore, there are two branches that are output from one state at time t and enter the same state at time (t + 1). Therefore, as shown in FIG. 105, at time (t + 1), the number of branches input to the state S is 4
The Viterbi decoding circuit 20017 determines the branch having the smallest path metric from the surviving paths as a thick line in FIG. The decoded symbol corresponding to each branch is 2 bits, and the 2-bit decoded symbol corresponding to the branch of the maximum likelihood path is output from the path memory 20021 to the symbol / byte conversion circuit 20004 in FIG.

On the other hand, FIG. 106 shows QPSK (r = 3/4,
FIG. 14 is a trellis diagram showing an operation of the Viterbi decoding circuit 20017 in the case of (）) and BPSK (r = １ ／).
As shown in FIG. 91, in the convolutional encoder 10007 of the error correction encoding apparatus 10001, the MSB D [2]
Is invalid. Therefore, one branch is output from one state at time t and enters the same state at time (t + 1). As shown in FIG. 106, at time (t + 1), the number of branches input to the state S is 2
The Viterbi decoding circuit 20017 determines the branch having the smallest path metric from among them as a surviving path, for example, as indicated by the thick line in FIG. The decoded symbol corresponding to each branch is 1 bit, and the path memory 2002
A 1-bit decoded symbol corresponding to the branch of the maximum likelihood path from 1 is output to the symbol / byte conversion circuit 20004.

As shown in FIG. 91, the convolution circuit 10014 is provided with six registers. Therefore, the number of states in both the trellis diagrams of FIGS. 105 and 106 is 64. That is, the state “000000” to the state “11”
1111 ".

On the other hand, when the PSK demodulated symbol data sequence is input to high / low hierarchy selection signal generation circuit 20003,
As shown in FIG. 100, the 8PSK hard decision circuit 22022
According to the transmission mode output from the transmission control information decoding circuit 20010, only the TC-8PSK (r = 2/3) slot is hard-decided to the TC-8PSK code point shown in FIG. 96, and one symbol = 3 bits Is output. The M-stage delay circuit 20032 is a Viterbi decoder 20002
, And outputs the BER to the BER measurement circuit 20004 at the same timing. Further, each symbol (1 symbol = 2 bits) of the Viterbi decoded data of the TC-8PSK slot output from the Viterbi decoder 20002 is input to the convolution circuit 20025. The convolution circuit 20025 corresponds to the convolution circuit 1 shown in FIG.
It has the same configuration as 0014. Here, the data of each symbol (1 symbol = 3 bits) subjected to reconvolution coding is output to the BER measurement circuit 20004.

The BER measuring circuit 20004 is a TC-8PS
The BER is measured by comparing each symbol (1 symbol = 3 bits) of the K slot, and a high / low layer selection signal ('H' = high layer, 'L' = low layer) is generated based on the result. , To an MPEG decoder (not shown) following the error correction circuit 20001. When the BER is low, an “H” signal is output, and when the BER is high, an “L” signal is output. When the 'H' signal is input, the MPEG decoder MPEG-decodes the high-layer signal and outputs an image to the monitor, and outputs the 'L' signal.
When a signal is input, the low-level signal is MPEG-decoded and an image is output to a monitor.

The symbol / byte conversion circuit 200 shown in FIG.
Reference numeral 04 converts the input Viterbi decoded symbol data sequence into a byte data sequence corresponding to the transmission mode of each slot, according to the transmission mode output from the transmission control information decoding circuit 20010. This state is shown in FIG.
In TC-8PSK (r = 2/3), 4 symbols (1 symbol = 2 bits) are collected and converted into byte data.
QPSK (r = 3/4, 1/2) and BPSK (r = 1
/ 2), 8 symbols (1 symbol = 1 bit) are collected and converted into byte data. Then, these converted data are output to the de-interleave circuit 20005.

Here, the data sequence per frame output from error correction encoding apparatus 10001 is shown in FIG.
TS1: <high-layer image> TC-8PSK: 22 slots <low-layer image> QPSK (r = ｒ): 2 slots (of which, dummy 1 slot) TS2: <high-layer image Image> TC-8PSK: 20 slots <Low-layer image> BPSK (r = 1/2): 4 slots (including 3 dummy slots). As shown in FIG. 108 (a), the error correction circuit 2
The symbol data sequence of one frame (= 39168 symbols) input to 0001 is a Viterbi decoder 20002
Is Viterbi-decoded. Then, as shown in FIG. 108B, the symbol / byte conversion circuit 20004 converts the data into a byte data sequence and outputs the data.

The de-interleaving circuit 20005 performs de-interleaving, and the de-interleaved data is output to the MPEG synchronization byte / dummy slot insertion circuit 20006. In this de-interleaving process, block de-interleaving with a depth of 8 is performed for each of the 203 bytes except for the TMCC portion (48 bytes in terms of TC-8PSK conversion) in units of slots for 48 slots. However, this is not performed for the dummy slots. As shown in FIG.
Assuming that the deinterleaving is × 203, block deinterleaving with a depth of 8 is performed in the superframe direction for each slot. In this manner, the ith slots of the first to eighth frames are collectively deinterleaved, and
Return to the i-th slot every time (1 ≦ i ≦ 48). The de-interleave processing as described above has a write / read direction opposite to that of the interleave circuit 10005 on the transmission side.

FIG. 110 shows a de-interleave circuit 200.
05 is a configuration example. This de-interleave circuit 20
005 is a write address generation circuit 20026, a read address generation circuit 20007, and a memory circuit 200027.
028. In order to perform de-interleaving, the memory circuit 20028 uses a memory area of two banks of one superframe (48 × 8 slots). Here, the actual write address value for the i-th slot is as follows. The numbers indicate frame-byte. Start 2nd Byte 203th Byte First Frame: 1-1 2-1 ... 3-26 Second Frame: 4-26 5-26 ... 6-51 Third Frame: 7-51 8-51 ... 1-77 Fourth frame: 2-77 3-77 ... 4-102 Fifth frame: 5-102 6-102 ... 7-127 Sixth frame: 8-127 1-128 ... 2- 153 7th frame: 3-153 4-153 ... 5-178 8th frame: 6-178 7-178 ... 8-203

As described above, the de-interleave circuit 2
[0005] In the 0005, a block de-
Interleaving is performed for 48 slots. However, as shown in FIG. 108 (c), the TMCC section of each frame is used during a period of 48 bytes (for 48 slots) of MPEG synchronization. Therefore, the de-interleave circuit 20005
Outputs each slot with a gap of one byte of MPEG synchronization at the beginning of each slot. Further, the de-interleave circuit 20005 has a space corresponding to the dummy slot, and as shown in FIG.
Outputs slots (including dummy slots) at a constant speed.

De-interleave circuit 2 shown in FIG.
The operation of 0005 is as follows. As shown in FIG. 109, the write address generation circuit 2
0026, a read address generation circuit 20027 generates a write address and a read address, respectively,
Output to the memory circuit 20028. As shown in FIG. 108 (b), the byte data sequence output from the symbol / byte conversion circuit 20004 is read / written by the memory circuit 20028 in accordance with the write address and the read address, and the data is read / written as shown in FIG. 108 (c). The interleaved byte data sequence is output to MPEG synchronization byte / dummy slot insertion circuit 20006 of FIG. However, according to the dummy slot information output from the transmission control information decoding circuit 20010, the write address generation circuit 20026 and the read address generation circuit 20026
0027 skips addresses for dummy slots and sequentially generates addresses for valid slots.

The MPEG synchronization byte / dummy slot insertion circuit 20006 inserts an MPEG synchronization byte at the beginning of each slot. And transmission control information decoding circuit 200
In accordance with the dummy slot information output from 10, an MPEG null packet is inserted in the dummy slot section, and a byte data sequence as shown in FIG. 108D is output to the de-randomizing circuit 20007.

FIG. 111 shows a de-randomizing circuit 2000.
7 shows a configuration example. De-randomizing circuit 20007
Is a PN generation circuit 20032, a P / S conversion circuit 20030, an S / P conversion circuit 20031, a gate signal generation circuit 20032, and an ex-or (exclusiv
e-or) circuit 20033. The de-randomizing circuit 20007 is a randomizing circuit 100 on the transmitting side.
Similarly to FIG. 04, 1 is added to the data series in FIG.
De-randomizing is performed at the superframe cycle. As shown in FIG. 111, PN generator 20029 is intended for performing signal processing using the generator polynomial ^{(1 + x 14 + x 15} ), is reset by the second byte of the first frame of each superframe, the initial value "100101010000000 Is substituted. The multiplication with the input data converted into the bit series by the P / S conversion circuit 20030 is performed by an ex-or circuit 2003.
3 is performed. The result of the multiplication is converted into a byte data series by the S / P conversion circuit 20031 and output to the RS decoding circuit 20008 of FIG. However, as shown in FIG.
Due to the gate signal generated by the gate signal generation circuit 20032, the PN generation circuit 20002 does not multiply the data as free-run during the first byte of each 204 bytes of the slot and the period of the dummy slot.

The RS decoding circuit 20008 decodes the RS (204, 188) for each 204-byte slot output from the de-randomizing circuit 20007 and outputs the result to the speed conversion circuit 200009. However, the RS decoding circuit 20008 does not decode the dummy slot based on the dummy slot information output from the transmission control information decoding circuit 20010.

The speed conversion circuit 20009 selects one selected TS from the data sequence of 48 slots per frame output from the RS decoding circuit 20008,
As shown in FIG. 108 (e), the speed conversion is performed, and the error correction data sequence (TS) is output to an MPEG decoder (not shown).

FIG. 113 shows an example of the configuration of the speed conversion circuit 20009. The speed conversion circuit 200009 indicated by a dotted line includes a write address generation circuit 20034, a read address generation circuit 20035, and a memory circuit 20036. In addition, in order to select TS and perform speed conversion,
Memory circuit 20036 is for one frame (48 slots)
Memory area. FIG. 113 also shows a transmission control information decoding circuit 20010 and a channel selection circuit 20011.

When channel selection information (16-bit TS_ID) is input from an MPEG decoder (not shown) to the channel selection circuit 20011, the channel selection circuit 20011 outputs TS_ID to the transmission control information decoding circuit 20010. The transmission control information decoding circuit 20010 uses the relative TS / T shown in FIG.
Referring to the S correspondence table, the relative TS number of the corresponding TS_ID is selected. Next, referring to the relative TS / slot information shown in FIG. 83, the slot number information of the selected relative TS number is output to the channel selection circuit 20011. Tuning circuit 2001
1 outputs a slot selection signal for selecting a TS to the speed conversion circuit 20009 from the slot number information.

In the speed conversion circuit 20009, a data sequence of one frame (48 slots) is sequentially written in the memory circuit 20036 based on the write address output from the write address generation circuit 20034. The read address generation circuit 20035 includes a tuning circuit 2001
From the slot selection signal output from 1, a read address including only the selected N slots including the dummy slot is generated and output to the memory circuit 20036.

Only the N slots selected by the memory circuit 20036 are speed-converted and output at an input speed of N / 48 to an MPEG decoder (not shown). Fig. 108
In the case of (e), N = 24. For each slot (204 bytes) output from the memory circuit 20036, the read address generation circuit 20035 provides an “H” signal for the MPEG packet valid period (188 bytes) and an “L” for the RS code parity section (16 bytes). 108, an enable signal, which is a signal, is generated as shown in FIG. 108 (e) and output to an MPEG decoder (not shown). With this enable signal, the MPEG decoder allows the MPEG packet valid period (188
Byte).

FIG. 1 output from memory circuit 20036
Regarding the output series 08 (e), the memory circuit 20036
FIGS. 114 to 117 show the manner of writing / reading to / from the memory. To the memory circuit 20036, a data sequence of 48 slots including dummy slots per frame is input at a constant speed. FIG. 108 (e) shows two types of TSs.
In this figure, TS1 (24 slots per frame) is selected and output at half the input (= 24/48).

FIG. 114 shows two slots T at the beginning of a frame.
S1 (1) to (2) are input to the memory circuit 20036 and written. In the meantime, one slot TS1 (1) is read from the memory circuit 20036 and output.

FIG. 115 shows the time point when the 20 slots TS1 (3) to (22) subsequent to FIG. 114 are input to the memory circuit 20036 and written. In the meantime, 10 slots TS1 (2) to TS1 (11) are stored in the memory circuit 20.
036 and output.

FIG. 116 shows the time points when the 22 slots TS2 (1) to (20) and TS1 (23) subsequent to FIG. 115 and the dummy 1 slot are input to the memory circuit 20036 and written. Meanwhile, 11 slot TS
1 (12) to TS1 (22) are read from the memory circuit 20036 and output.

FIG. 117 shows four slots following FIG. 116,
That is, TS2 (21) and three dummy slots correspond to the memory circuit 2
0036 indicates the point in time when the data is written.
In the meantime, two slots, ie, TS1 (23) and one dummy slot, are read from the memory circuit 20036 and output.

As shown in FIGS. 114 to 117, when a data sequence of one frame (48 slots: including dummy slots) is input, the speed conversion circuit 200009 receives N slots of the selected TS. 114 to 11
In the case of 7, select TS1: N = 24 and input N / 4
The data is output to an MPEG decoder (not shown) at a speed of 8.

[0082]

The error correction circuit 20001 which has been studied conventionally operates with the above configuration.
The error correction data sequence (TS) has been output to the MPEG decoder. By the way, in the Viterbi decoder 20002 of the error correction circuit 20001, even when the transmission mode (the number of phases and the coding rate) changes between slots, control at the time of switching the transmission mode has not been considered.

FIG. 118 is a trellis diagram showing a state of path memory 20021 (path memory length = J) in Viterbi decoder 20002 at the time of transmission mode switching. FIG.
18 (a) shows the case where the last symbol of the transmission mode A is
The time point when the data is input to the path memory 20021 of 00 is shown.
FIG. 118B shows a point in time when the first symbol of the next transmission mode B is input to the path memory 20021. FIG.
8 (c) shows the point in time up to the next (J-2) symbol of the transmission mode B being input to the path memory 20021.

In the conventional error correction circuit 20001, the state of the latest symbol input to the path memory 20021, ie, the state having the smallest path metric among all the states of the J-th symbol in the path memory 20021, is changed from The surviving path input to the state is returned by (J-1) symbols before, and the first symbol in the corresponding path memory 20021 is output as Viterbi decoded symbol data.

However, FIGS. 118 (b) and (c)
In the trellis diagram shown in FIG.
, The minimum path metric is determined in all the states of the input symbols of the transmission mode A, and the Viterbi decoded data of the transmission mode A before the mode switching, that is, the path memory
This means that Viterbi decoded symbol data is output for the (J-1) symbol remaining in 1.

For example, as shown in FIG.
Consider a case where TC-8PSK (r = ２) is transmitted after TMCC192 symbols transmitted by SK (r = １ ／). In this case, the transmission mode A is BPSK (r = Ｋ) in FIG.
C-8PSK (r = 2/3). In the conventional Viterbi decoding method, the TMCC symbol of the (J-1) symbol remaining in the path memory 20021 at the time of mode switching is the minimum path in the TC-8PSK (r = 2/3) symbol sequence having a small inter-code distance. Decoding is performed according to the metric determination result. Therefore, there is a problem that the (J-1) symbol is worse than the original error rate of BPSK (r = 1/2).

In the conventional Viterbi decoding method, FIG.
As shown in the figure, a TAB signal (w1, w2, w
In 3), the PSK demodulated data sequence is directly used as the Viterbi decoder 2 even though the last 20 symbols are known.
0002. Therefore, there is also a problem that the feature of the fixed sequence of the TAB signal is not used.

Further, the conventional error correction circuit 20001
As shown in FIG. 110, the deinterleave circuit 2000
In 5, the deinterleaving is performed using the byte data area of 2 superframes of the memory circuit 20028, that is, 48 slots × 8 frames × 2 banks. However, in digital BS broadcasting, one transponder multiplexes a plurality of TSs for transmission and reception, and the error correction circuit 20001 finally outputs only one TS data sequence. As shown in FIG. 108 (b), the data sequence input to the de-interleave circuit 20005 is per frame (48 slots). TS1: <high-layer image> TC-8PSK: 22 slots <low-layer image> QPSK (r = 1/2): 1 slot (including one dummy slot) TS2: <high-layer image> TC-8PSK: 20 slots <low-layer image> BPSK (r = 1/2): 1 slot ( (Dummy, 3 slots). In this case, TS1 or T
Whichever of S2 is selected, when all slots of one TS are transmitted by TC-8PSK, a maximum of 24 slots per frame may be deinterleaved and output. Therefore, the conventional de-interleave circuit 20005
Has a problem that deinterleaving is performed using an unnecessary memory area.

Further, the conventional error correction circuit 20001
In the speed conversion circuit 20009 shown in FIG.
The selection of the TS and the speed conversion are performed using the memory area of one frame of the memory circuit 20036. However, one frame of one TS, that is, up to two in the above example
TS selection and speed conversion are possible only with the memory area of 4 slots. Therefore, the conventional speed conversion circuit 200009
Has a problem in that TS selection and speed conversion are performed using an unnecessary memory area.

Also, the de-interleave circuit 20005
Originally has a memory, and as described above, when the TS is selected by the de-interleave circuit and the speed conversion is performed at the same time, the speed conversion circuit 200009 is unnecessary. Therefore,
From this point of view, the conventional error correction circuit 200
01 has an unnecessary speed conversion circuit 200009.

In this case, the data sequence input to the de-randomizing circuit 20007 is not a continuous slot but a data sequence of discrete slots. Therefore, when the conventional de-randomizing circuit 20007 is used, de-randomizing cannot be performed, so that the de-interleaving circuit 200
The configuration of selecting the TS and performing the speed conversion in 05 cannot be taken. Therefore, the configuration of the conventional de-randomizing circuit 20007 has a problem that the speed conversion circuit 200009 cannot be unnecessary.

The present invention has been made in view of such a conventional problem. In particular, according to the first and second aspects of the present invention, symbols before transmission mode switching remaining in the path memory are An error correction circuit capable of determining the minimum path metric based on the path metric accumulated up to the last symbol of the transmission mode before switching and outputting it as Viterbi decoded data and capable of Viterbi decoding not affected by the symbol of the transmission mode after switching. The purpose is to provide.

In particular, according to the third aspect of the present invention, only the one state having the minimum path metric among all the states in the last symbol before the transmission mode switching is made valid, and the other states are made invalid to output the Viterbi decoded data. It is another object of the present invention to provide an error correction circuit capable of performing Viterbi decoding that is not affected by symbols in a transmission mode after switching.

In particular, the invention according to claim 4 takes another state by setting a minimum value that can take only one state path metric having the minimum path metric among all states in the last symbol before transmission mode switching. An object of the present invention is to provide an error correction circuit capable of performing Viterbi decoding that is not affected by symbols in a transmission mode after switching by resetting to a maximum value obtained.

In particular, according to the fifth aspect of the present invention, when the number of modulation levels (the number of phases) after the transmission mode switching is larger than that before the switching,
Or only when the modulation level is the same and the coding rate is large,
An object of the present invention is to provide an error correction circuit that performs Viterbi decoding that is not affected by symbols in a transmission mode after switching.

In particular, the invention according to claim 6 is an error correction circuit which does not perform switching control in Viterbi decoding according to claims 1 to 4 when a fixed symbol sequence is included following the last symbol before transmission mode switching. The purpose is to provide.

In particular, in the invention according to claim 7 or claim 8, when a fixed symbol sequence is included following the last symbol before the transmission mode switching, the state of the convolutional encoder is determined in the fixed symbol sequence. From the symbol to the last fixed symbol to the final fixed symbol, only the determined one state is valid, and the other states are invalid, and Viterbi decoded data is output.
An object of the present invention is to provide an error correction circuit capable of performing Viterbi decoding which is not affected by symbols in a transmission mode after switching by using a fixed symbol sequence.

In particular, according to the ninth aspect of the present invention, at least one symbol in an input fixed symbol sequence in a section from a symbol in which the state of the convolutional encoder is determined to a final fixed symbol is determined. An error correction circuit capable of outputting Viterbi decoded data with only one state being valid and disabling the other states and utilizing a fixed symbol sequence and capable of performing Viterbi decoding without being affected by symbols in the switched transmission mode. The purpose is to provide.

In particular, when the fixed symbol sequence for termination is included following the last symbol before switching, the input fixed symbol sequence
From the symbol for which the state of the convolutional encoder is determined to the final fixed symbol, reset to the minimum value that can take only the path metric of one determined state and the maximum value that can take the other states. Accordingly, an object of the present invention is to provide an error correction circuit capable of performing Viterbi decoding which is not affected by symbols in a transmission mode after switching.

In particular, when the fixed symbol sequence for the termination is included following the last symbol before the switching, the invention according to claim 11 includes:
In a section from the symbol in which the state of the convolutional encoder is determined to the final fixed symbol, at least one symbol can take another state to the minimum value that can take only the path metric of the determined one state. An object of the present invention is to provide an error correction circuit capable of performing Viterbi decoding that is not affected by symbols in a transmission mode after switching by resetting to a maximum value.

In particular, the invention according to claim 12 or 13 is characterized in that, when a fixed symbol sequence is included subsequent to the last symbol before the transmission mode switching, a symbol in which the state of the encoder is determined in the fixed symbol sequence. From the first fixed symbol to the last fixed symbol, with respect to the fixed symbol sequence, only one branch corresponding to the fixed symbol sequence among the branches output from each state in Viterbi decoding is made valid, and the other branches are made invalid and Viterbi decoding is performed. An object of the present invention is to provide an error correction circuit capable of outputting data and using a fixed symbol sequence to perform Viterbi decoding without being affected by symbols in a transmission mode after switching.

In particular, when the fixed symbol sequence is included following the last symbol before the transmission mode switching, the invention according to claim 14 or 15 performs coding from the first symbol in the input fixed symbol sequence. For a symbol whose state is determined, only the state corresponding to the input of that symbol among all the states in Viterbi decoding is made valid, and the other states are made invalid and the state is changed every time one symbol is input. After the state is fixed to one state, only one state is made valid, the other states are made invalid, and Viterbi decoded data is output. Using a fixed symbol sequence, Viterbi which is not affected by symbols in the transmission mode after switching is used. An object of the present invention is to provide an error correction circuit capable of decoding.

In particular, in the invention according to claim 16, when a fixed symbol sequence is included subsequent to the last symbol before the transmission mode switching, in the input fixed symbol sequence, the encoder starts with the first symbol in the encoder. Up to the symbol whose state is determined, in the input fixed symbol sequence, from the symbol whose state of the convolutional encoder is determined to the final fixed symbol, up to that symbol out of all the states in Viterbi decoding Is reset to the minimum value that can take only the path metric of the state corresponding to the input, to the maximum value that can take other states, and after it is determined to be 1 state, only the path metric of the determined 1 state is changed. By resetting to the minimum possible value and the maximum possible value for other states, Viterbi decoding not affected by the symbol of the transmission mode after switching And to provide an error correction circuit capable.

In particular, in the invention according to claim 17 or 18, the fixed symbol sequence is changed to the code point of the fixed symbol sequence and input to the Viterbi decoder. An object of the present invention is to provide an error correction circuit capable of performing Viterbi decoding that is not affected by symbols of a transmission mode after switching by using a symbol sequence.

In particular, the present invention as defined in claim 19,
8, 17, and 18, in the input fixed symbol sequence, from the first symbol to the symbol for which the state of the encoder is determined, among the branches output from each state in Viterbi decoding, the fixed symbol sequence , The Viterbi decoding data is output with only one branch corresponding to... Valid and the other branches are invalidated. Viterbi decoding that is not affected by the symbol of the transmission mode after switching is performed using the fixed symbol sequence. It is an object to provide a correction circuit.

In particular, the invention described in claim 20 is the same as in claim 7,
In 8, 12, 13, 17, and 18, in the input fixed symbol sequence, from the first symbol to the symbol for which the state of the encoder is determined, up to that symbol out of all the states in Viterbi decoding. Only the status corresponding to the input is valid, and the other statuses are invalid.
Provided is an error correction circuit capable of reducing the state every time a symbol is input, outputting Viterbi decoded data while reducing the state, and using a fixed symbol sequence, capable of performing Viterbi decoding without being affected by symbols in a transmission mode after switching. With the goal.

The invention described in claim 21 is particularly advantageous in that
8, 17, and 18, in the input fixed symbol sequence, from the first symbol to the symbol for which the state of the encoder is determined, among the branches output from each state in Viterbi decoding, the fixed symbol sequence , Only one branch corresponding to the symbol is made valid, the other branches are made invalid, and among all the states in Viterbi decoding, only the state corresponding to the input up to the symbol is made valid,
The other states are invalidated, the state is reduced every time one symbol is input, the state is reduced, Viterbi-decoded data is output, and the characteristics of the fixed symbol sequence are used to the maximum extent to be affected by the symbols of the transmission mode after switching. An object of the present invention is to provide an error correction circuit capable of performing no Viterbi decoding.

In particular, the invention described in claim 22 is the same as
At 8, 10, 12, 13, 17, and 18, in the input fixed symbol sequence, from the first symbol to the symbol in which the state of the convolutional encoder is determined, among all states in Viterbi decoding, The minimum value that can take only the path metric of the state corresponding to the input up to the symbol is reset to the maximum value that can take another state, and after it is determined to be one state, the path of the determined one state is An error correction circuit capable of performing Viterbi decoding that is not affected by symbols in a transmission mode after switching by resetting to a minimum value that can take only a metric and a maximum value that can take another state. Aim.

[0109] In particular, the invention described in claim 23 is the invention according to claim 7,
At 8, 10, 17, and 18, in the input fixed symbol sequence, from the first symbol to the symbol for which the state of the convolutional encoder is determined, of the branches output from each state in Viterbi decoding , The fixed branch signal for validating only one branch corresponding to the fixed symbol sequence and disabling the other branches, and the state corresponding to the input of up to the symbol out of all states in Viterbi decoding. The state is reset to the minimum value that can take only the path metric, the maximum value that can take another state, and after it is determined to be one state, the other value is set to the minimum value that can take only the path metric of the determined one state. Provides an error correction circuit that can perform Viterbi decoding without being affected by transmission mode symbols after switching by resetting to the maximum possible value For the purpose of Rukoto.

In particular, according to the invention of claim 24, in a superframe, a data sequence transmitted after performing M interleavings of a depth N in slot units,
An object of the present invention is to provide an error correction circuit for deinterleaving only data of a selected L slot out of M slots of each frame and outputting data.

In particular, the invention according to claim 25 is characterized in that the maximum number of slots per frame selected is Lmax.
It is an object of the present invention to provide an error correction circuit that performs de-interleaving by using only two memory areas of the maximum (Lmax × N) slots and using only the minimum necessary memory area.

In particular, according to the twenty-sixth aspect of the present invention, an error correction method of deinterleaving only data of a selected L slot out of M slots of each frame and continuously outputting the data at an L / M speed of a transmission format. It is intended to provide a circuit.

In particular, the invention according to claim 27 is characterized in that a plurality of MPs
In a transmission method in which transmission is performed in a transmission format in which an EG transport stream is multiplexed, a data sequence transmitted by performing M interleavings of a depth N in a slot unit in a super frame is transmitted in M slots of each frame. It is an object of the present invention to provide an error correction circuit that outputs data by deinterleaving only data of a selected L slot.

In particular, when the maximum number of slots per frame occupied by one type of transport stream is Lmax, the area 2 banks of only the maximum (Lmax × N) slots of the memory circuit are provided. , And the channel selected by only the minimum necessary memory area is used.
An object of the present invention is to provide an error correction circuit that outputs data by deinterleaving only transport streams of different types.

In particular, when the maximum number of slots per frame occupied by one type of transport stream is Lmax and K is an integer of 2 or more, the maximum (Lmax × N × K) An error correction circuit is provided which uses only two slots of the area corresponding to the slots and deinterleaves only the selected transport streams of K types or less and outputs data using only the minimum necessary memory area. The purpose is to do.

In particular, the invention according to claim 30 includes a plurality of MPs.
In a transmission system in which transmission is performed in a transmission format in which EG transport streams are multiplexed, the M
An object of the present invention is to provide an error correction circuit which deinterleaves only data of a selected L slot among slots and continuously outputs the data at the L / M speed of the transmission format.

In particular, the invention according to claim 31 is a method for
In a transmission system in which transmission is performed in a transmission format in which EG transport streams are multiplexed, it is assumed that the selected J types of transport streams occupy L1, L2,..., Lj slots per frame. Then, of the M slots of each frame, data of a total of (L1 + L2 +... + Lj) slots per frame is deinterleaved, and the transmission format (L
An object of the present invention is to provide an error correction circuit that outputs continuously at a rate of 1 + L2 +... + Lj) / M.

In particular, the invention described in claim 32 or 33
When frame = M slots and 1 superframe = N frames, a data sequence transmitted by randomizing continuously in units of superframes is defined as a data sequence for each head data of (N × M) slots in one superframe. It has (N × M) kinds of initial values of derandomize,
Provided is an error correction circuit that, when data of L slots among M slots of each already selected frame is input, performs de-randomization for each input slot from an initial value corresponding to the input slot. The purpose is to:

In particular, in the invention according to claim 34, only the data of the selected L slot out of the M slots of each frame is read / written to / from the memory circuit, whereby the selected 1 slot is read.
It is an object of the present invention to provide an error correction circuit that continuously outputs data of L slots per frame at a rate of L / M of a transmission format.

In particular, according to the invention of claim 35, if the maximum number of slots per frame to be selected is Lmax,
It is an object of the present invention to provide an error correction circuit which uses a region of only a maximum Lmax slot of a memory circuit and continuously outputs selected data by speed conversion using only a minimum necessary memory region. .

In particular, the invention described in claim 36 is characterized in that a plurality of MPs
In a transmission system in which transmission is performed in a transmission format in which EG transport streams are multiplexed, the M
An error correction circuit that continuously outputs L-slot data per selected frame at a rate of L / M in a transmission format by reading / writing only data of a selected L-slot from a slot into a memory circuit. The purpose is to provide.

In particular, when the maximum number of slots per frame occupied by one type of transport stream is Lmax, an area corresponding to only the maximum Lmax slots of the memory circuit is used. An object of the present invention is to provide an error correction circuit that performs speed conversion and continuously outputs one type of transport stream selected by using only a minimum memory area.

In particular, when the maximum number of slots per frame occupied by one type of transport stream is Lmax and K is an integer of 2 or more, the maximum (Lmax × K ) A transport stream of K types or less selected using only an area corresponding to slots and using only a minimum necessary memory area,
An object of the present invention is to provide an error correction circuit that performs speed conversion and continuously outputs the result.

In particular, the invention of claim 39 is based on the assumption that the selected J types of transport streams occupy L1, L2,..., Lj slots per frame, respectively. The port streams are respectively represented by L1 / M, L2 / M,
An object of the present invention is to provide an error correction circuit that outputs data continuously in parallel at a speed of Lj / M.

In particular, the invention according to claim 40 is the invention according to claim 24.
Or an error correction circuit which performs deinterleaving in 25, receives an already selected L slot data sequence per frame as an input, and continuously outputs a data sequence at the L / M speed of the transmission format. Aim.

In particular, the invention according to claim 41 is the invention according to claim 24.
Or, if the maximum number of slots per frame to be selected is defined as Lmax by performing de-interleaving in 25, only the area of the maximum Lmax slots of the memory circuit is used, and only the minimum necessary memory area is used. It is an object of the present invention to provide an error correction circuit that performs speed conversion on data and continuously outputs the data.

In particular, the invention as set forth in claim 42 is characterized in that a plurality of MPs
A transmission system for transmitting data in a transmission format obtained by multiplexing an EG transport stream.
9, and the data sequence of L slots per frame that has been selected is input,
An object of the present invention is to provide an error correction circuit that continuously outputs a data sequence at a transmission format of L / M.

In particular, the present invention as defined in claim 43, comprises a plurality of MPs.
In a transmission system in which transmission is performed in a transmission format in which EG transport streams are multiplexed, if the maximum number of slots per frame occupied by one type of transport stream is Lmax, the deinterleaving in claims 27 to 29 is performed. The maximum Lma of the memory circuit
One type of transport channel selected using only the area of x slots and only the minimum required memory area
It is an object of the present invention to provide an error correction circuit that performs speed conversion on a stream and continuously outputs the stream.

[0129] In particular, the invention as set forth in claim 44 is characterized in that a plurality of MPs are provided.
28. In a transmission system for transmitting data in a transmission format in which EG transport streams are multiplexed, if the maximum number of slots per frame occupied by one type of transport stream is Lmax, and K is an integer of 2 or more. To 29, the area of only the maximum (Lmax × K) slots of the memory circuit is used, and only the minimum necessary memory area is used to select the K or less types of transport streams. An object of the present invention is to provide an error correction circuit that performs speed conversion and continuously outputs the result.

In particular, the invention described in claim 45 is characterized in that a plurality of MPs
In a transmission system in which transmission is performed in a transmission format in which EG transport streams are multiplexed, it is assumed that the selected J types of transport streams occupy L1, L2,..., Lj slots per frame. Then, the deinterleaving in claims 27 to 29 is performed, and the J types of transport streams are
Each of the transmission formats L1 / M, L2 / M, ...
An object of the present invention is to provide an error correction circuit that outputs continuously in parallel at a speed of Lj / M.

[0131]

According to the first aspect of the present invention, a data sequence on the transmitting side is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and each symbol has a different modulation scheme and coding rate. An error correction circuit for Viterbi decoding of a data sequence that has been convolutionally coded and transmitted by one convolutional encoder continuously, and converts the Viterbi decoded data when the modulation method and the coding rate are switched. At the time of output, when a signal for switching the symbol for determining the minimum path metric in the path memory is used as a switching control signal, the modulation of each input symbol according to the known modulation method and coding rate information between transmission and reception. In addition to performing Viterbi decoding corresponding to the system and coding rate, at the time of switching the modulation scheme and coding rate, the period before the switching control signal is output and the maximum before switching are performed. A Viterbi decoder that outputs Viterbi decoded data according to a path metric accumulated up to the symbol, and provides the Viterbi decoder with the modulation scheme / coding rate information of each symbol input to the Viterbi decoder, and provides a modulation scheme and encoding At the time of rate switching, a Viterbi decoder control circuit that generates the switching control signal and supplies the switching control signal to the Viterbi decoder during a period in which symbols of the modulation scheme and the coding rate before switching remain in the path memory of the Viterbi decoder And characterized in that:

According to the invention of claim 2 of the present application, a transmission frame is constituted by symbols of a plurality of modulation schemes and a plurality of coding rates, and information on a modulation scheme and a coding rate of each symbol is used as transmission control information for each frame. The error correction circuit includes a symbol of each frame, which exceeds a different modulation scheme and coding rate, and Viterbi-decodes a data sequence transmitted by being convolutionally coded by one convolutional coder continuously. When outputting a Viterbi decoded data at the time of switching the modulation scheme and the coding rate, when a signal for switching a symbol for determining the minimum path metric in the path memory is used as a switching control signal, a known modulation between transmission and reception is used. Performs Viterbi decoding corresponding to the modulation scheme and coding rate of each input symbol according to the scheme and coding rate information, and modulates and encodes. During the switching, the Viterbi decoder that outputs Viterbi decoded data based on the path metric accumulated up to the last symbol before the switching while the switching control signal is being output, and decodes the transmission control information included in each frame. A transmission control information decoding circuit that performs the modulation method and the coding rate information of each symbol input to the Viterbi decoder from the decoding result output from the transmission control information decoding circuit to the Viterbi decoder. At the time of switching between the system and the coding rate, the switching control signal is generated during the period in which the symbol of the modulation method and the coding rate before the switching remains in the path memory of the Viterbi decoder, and the Viterbi signal supplied to the Viterbi decoder is generated. And a decoder control circuit.

The invention of claim 3 of the present application is directed to claim 1 or 2
In the error correction circuit, the Viterbi decoder control circuit, the modulation scheme and coding rate information of each symbol input to the Viterbi decoder is provided to the Viterbi decoder, when switching the modulation scheme and coding rate , Among all states in the last symbol before switching, only the one state having the minimum path metric is made valid, and the switching control signal for invalidating the other states is generated and provided to the Viterbi decoder. It is characterized by having been replaced.

The invention of claim 4 of the present application is directed to claim 1 or 2
In the error correction circuit, the Viterbi decoder control circuit, the modulation scheme and coding rate information of each symbol input to the Viterbi decoder is provided to the Viterbi decoder, when switching the modulation scheme and coding rate The switching control signal for resetting to a minimum value that can take only one state path metric having the minimum path metric among all states in the last symbol before switching, and a maximum value that can take another state. Is generated and replaced with a configuration to be applied to the Viterbi decoder.

According to a fifth aspect of the present invention, in the error correction circuit according to any one of the first to fourth aspects, the Viterbi decoder control circuit comprises a modulation multi-level number after switching of a modulation scheme and a coding rate. Is larger than before switching, or only when the modulation multi-level number is the same and the coding rate is large, the switching control signal is generated and given to the Viterbi decoder.

According to a sixth aspect of the present invention, in the error correction circuit according to any one of the first to fifth aspects, the Viterbi decoder control circuit, when switching the modulation scheme and the coding rate, performs the switching before the switching. When a fixed symbol sequence for termination is included following the last symbol, the switching control signal is not generated.

According to the invention of claim 7 of the present application, the data sequence on the transmission side is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and when the modulation scheme and the coding rate are switched, the last symbol before switching is performed. Followed by a fixed symbol sequence for termination, wherein each symbol is convolutionally coded by one convolutional encoder and transmitted over a different modulation scheme and coding rate. An error correction circuit that performs Viterbi decoding of the data sequence, and for a fixed symbol sequence, when a signal indicating a period in which the state of the convolutional encoder is determined is used as a determined state signal, a known modulation method between transmission and reception. In accordance with the coding rate information, Viterbi decoding corresponding to the modulation scheme and coding rate of each input symbol is performed, and when the modulation scheme and coding rate are switched, the decision is made. A Viterbi decoder that performs Viterbi decoding corresponding to the state signal, and gives the modulation scheme / coding rate information of each symbol input to the Viterbi decoder to the Viterbi decoder, and switches the modulation scheme and the coding rate. If a fixed symbol sequence for termination is included following the last symbol before switching, among the input fixed symbol sequences, the symbol from which the state of the convolutional encoder is determined is the last fixed symbol sequence. Up to 1 confirmed
And a Viterbi decoder control circuit that generates the deterministic state signal for validating only the state and invalidating the other states and provides the generated signal to the Viterbi decoder.

According to the invention of claim 8 of the present application, the transmission frame is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and at the time of switching the modulation scheme and the coding rate, the transmission frame follows the last symbol before the switching. There is a case where a fixed symbol sequence for termination is included, information on the modulation scheme and coding rate of each symbol is included as transmission control information for each frame, and the symbol of each frame exceeds a different modulation scheme and coding rate. An error correction circuit for continuously Viterbi-decoding a data sequence that has been convolutionally encoded and transmitted by one convolutional encoder, wherein the state of the convolutional encoder is determined for a fixed symbol sequence. When a signal indicating a period of time to be performed is set as a definite state signal, a bit rate corresponding to the modulation scheme and coding rate of each input symbol according to the modulation scheme and coding rate information. A Viterbi decoder that performs decoding and performs Viterbi decoding corresponding to the deterministic state signal when the modulation scheme and the coding rate are switched, and a transmission control information decoding circuit that decodes the transmission control information included in each frame And extracting, from the decoding result output from the transmission control information decoding circuit, the modulation scheme / coding rate information of each symbol input to the Viterbi decoder, and supplies the extracted modulation scheme / coding rate information to the Viterbi decoder. At the time of rate switching, if a fixed symbol sequence for termination is included following the last symbol before switching, among the input fixed symbol sequences, the symbol from which the state of the convolutional encoder is determined is determined. For the last fixed symbol, only the determined one state is made valid, and the determined state signal for invalidating the other states is generated. Is characterized in that it comprises a Viterbi decoder control circuit for applying to the vessel, the.

The invention of claim 9 of the present application is directed to claim 7 or 8
In the error correction circuit, the Viterbi decoder control circuit extracts the modulation scheme / coding rate information of each symbol input to the Viterbi decoder, and supplies the extracted modulation scheme / coding rate information to the Viterbi decoder. At the time of switching, if a fixed symbol sequence for termination is included following the last symbol before switching, the last fixed symbol sequence is input from the symbol in which the state of the convolutional encoder is determined. In a section up to the symbol, for at least one symbol, only the one state in which the state of the convolutional encoder has been determined is made valid, and the determined state signal for invalidating other states is generated, and the Viterbi decoding is performed. It is characterized by having been replaced with a configuration given to a vessel.

According to a tenth aspect of the present invention, in the error correction circuit of the seventh or eighth aspect, the Viterbi decoder control circuit is configured to control the modulation method / coding rate information of each symbol input to the Viterbi decoder. Is given to the Viterbi decoder, and when switching the modulation scheme and coding rate, if a fixed symbol sequence for termination is included following the last symbol before switching, among the input fixed symbol sequences, From the symbol for which the state of the convolutional encoder is determined to the final fixed symbol, the state is reset to the minimum value that can take only the path metric of one determined state and to the maximum value that can take another state. For generating the deterministic state signal and providing the same to the Viterbi decoder.

According to an eleventh aspect of the present invention, in the error correction circuit according to the seventh or eighth aspect, the Viterbi decoder control circuit is configured to control the Viterbi decoder to obtain the modulation scheme / coding rate information of each symbol input to the Viterbi decoder. Is given to the Viterbi decoder, and when switching the modulation scheme and coding rate, if a fixed symbol sequence for termination is included following the last symbol before switching, among the input fixed symbol sequences, In a section from the symbol in which the state of the convolutional encoder is determined to the final fixed symbol, at least one symbol is set to a minimum value that can take only the determined one state path metric, and the other state is set. The present invention is characterized in that the determinate state signal for resetting to the maximum value to be obtained is generated and the configuration is given to the Viterbi decoder.

According to a twelfth aspect of the present invention, the data sequence on the transmission side is composed of symbols of a plurality of modulation schemes and a plurality of coding rates. Followed by a fixed symbol sequence for termination, wherein each symbol is convolutionally coded by one convolutional encoder and transmitted over a different modulation scheme and coding rate. Error correction circuit that performs Viterbi decoding of a data sequence that has been transmitted, and for a fixed symbol sequence, when a signal specifying a branch in a state transition of a trellis diagram is a fixed branch signal, a known modulation method and coding rate between transmission and reception. According to the information, while performing the Viterbi decoding corresponding to the modulation scheme and the coding rate of each input symbol, when switching the modulation scheme and the coding rate, A Viterbi decoder that performs Viterbi decoding corresponding to the fixed branch signal, and provides the Viterbi decoder with the modulation scheme and coding rate information of each symbol input to the Viterbi decoder, and switches between a modulation scheme and a coding rate. Sometimes
When a fixed symbol sequence for termination is included following the last symbol before switching, the fixed symbol sequence is one of the branches output from each state in Viterbi decoding that corresponds to the fixed symbol vol sequence. A Viterbi decoder control circuit that generates the fixed branch signal for validating only one branch and invalidating the other branches and provides the fixed branch signal to the Viterbi decoder.

According to a thirteenth aspect of the present invention, a transmission frame is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and at the time of switching between the modulation schemes and the coding rates, the transmission frame follows the last symbol before the switching. There is a case where a fixed symbol sequence for termination is included, information on the modulation scheme and coding rate of each symbol is included as transmission control information for each frame, and the symbol of each frame exceeds a different modulation scheme and coding rate. An error correction circuit for continuously performing Viterbi decoding on a data sequence that has been convolutionally encoded and transmitted by one convolutional encoder, and specifies a branch in a state transition of a trellis diagram for a fixed symbol sequence When the signal to be converted is a fixed branch signal, the signal corresponding to the modulation scheme and coding rate of each input symbol is A Viterbi decoder that performs Viterbi decoding and performs a Viterbi decoding corresponding to the fixed branch signal when a modulation scheme and a coding rate are switched, and a transmission control information decoder that decodes the transmission control information included in each frame. Circuit, from the decoding result output from the transmission control information decoding circuit, extracts the modulation scheme / coding rate information of each symbol input to the Viterbi decoder, and supplies the extracted modulation scheme / coding rate information to the Viterbi decoder. If the fixed symbol sequence for termination is included following the last symbol before switching when the conversion rate is switched, the fixed symbol sequence is selected from among the branches output from each state in Viterbi decoding. Generating the fixed branch signal for validating only one branch corresponding to the other branch and invalidating the other branch, It is characterized in that it comprises a Viterbi decoder control circuit for applying to the decoder.

According to the invention of claim 14 of the present application, the data sequence on the transmitting side is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and when the modulation scheme and the coding rate are switched, the last symbol before the switching is performed. Followed by a fixed symbol sequence for termination, wherein each symbol is convolutionally coded by one convolutional encoder and transmitted over a different modulation scheme and coding rate. Error correction circuit for Viterbi decoding of the data sequence, wherein, for a fixed symbol sequence, when a signal for reducing the number of states in the trellis diagram is used as a state reduction signal, according to known modulation scheme / coding rate information between transmission and reception. Performs Viterbi decoding corresponding to the modulation scheme and coding rate of each input symbol, and, when switching the modulation scheme and coding rate, responds to the state reduction signal. A Viterbi decoder that performs Viterbi decoding, and the modulation scheme / coding rate information of each symbol input to the Viterbi decoder is given to the Viterbi decoder. When a fixed symbol sequence for termination is included following a symbol, Viterbi decoding is performed on the input fixed symbol sequence from the first symbol to the symbol for which the state of the convolutional encoder is determined. Out of all the states, only the state corresponding to the input up to that symbol is made valid, the other states are invalidated, and the state is reduced every time one symbol is input. And a Viterbi decoder control circuit for generating the state reduction signal for invalidating other states and providing the state reduction signal to the Viterbi decoder. A.

According to the invention of claim 15 of the present application, a transmission frame is constituted by symbols of a plurality of modulation schemes and a plurality of coding rates, and at the time of switching between the modulation schemes and the coding rates, the transmission frame follows the last symbol before the switching. There is a case where a fixed symbol sequence for termination is included, information on the modulation scheme and coding rate of each symbol is included as transmission control information for each frame, and the symbol of each frame exceeds a different modulation scheme and coding rate. An error correction circuit for performing Viterbi decoding of a data sequence that has been convolutionally encoded and transmitted by one convolutional encoder continuously, the signal being used to reduce the number of states of a trellis diagram for a fixed symbol sequence When is a state reduction signal, according to the modulation scheme and coding rate information, when performing Viterbi decoding corresponding to the modulation scheme and coding rate of each input symbol In addition, at the time of switching the modulation scheme and the coding rate, a Viterbi decoder that performs Viterbi decoding corresponding to the state reduction signal, a transmission control information decoding circuit that decodes the transmission control information included in each frame, From the decoding result output from the transmission control information decoding circuit, the modulation scheme / coding rate information of each symbol input to the Viterbi decoder is extracted and provided to the Viterbi decoder, and the modulation scheme and coding rate are switched. Sometimes, when a fixed symbol sequence for termination is included following the last symbol before switching, the last fixed symbol sequence from the symbol in which the state of the convolutional encoder is determined in the input fixed symbol sequence is used. For symbols up to the symbol, only the state corresponding to the input up to the symbol among all the states in Viterbi decoding is made valid, and the other states are made invalid and 1 Each time a symbol is input, the state is reduced. After the state is determined to be one, the state reduction signal for validating only one state and invalidating the other states is generated, and the Viterbi decoder is supplied to the Viterbi decoder. Device control circuit.

According to a sixteenth aspect of the present invention, in the error correction circuit according to the fourteenth or fifteenth aspect, the Viterbi decoder control circuit is configured to control the modulation scheme / coding rate information of each symbol input to the Viterbi decoder. To the Viterbi decoder,
When the modulation scheme and the coding rate are switched, if a fixed symbol sequence for termination is included following the last symbol before the switching, the state of the convolutional encoder in the input fixed symbol sequence. From the symbol in which the symbol is determined to the final fixed symbol, other states can be set to the minimum value that can take only the path metric of the state corresponding to the input up to the symbol among all states in Viterbi decoding. After resetting to the maximum value and confirming to 1 state,
Generating the state reduction signal for resetting to a minimum value that can take only the determined one state path metric and to a maximum value that can take another state, and replacing the state reduction signal with a configuration that is provided to the Viterbi decoder. It is characterized by the following.

According to the invention of claim 17 of the present application, the data sequence on the transmission side is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and when the modulation scheme and the coding rate are switched, the last symbol before switching is switched. Followed by a fixed symbol sequence for termination, wherein each symbol is convolutionally coded by one convolutional encoder and transmitted over a different modulation scheme and coding rate. An error correction circuit for Viterbi-decoding the decoded data sequence, wherein when a signal to be converted into demodulated I / Q data corresponding to a fixed symbol is used as a symbol coordinate conversion signal, an input section of the fixed symbol sequence according to the symbol coordinate conversion signal For, the input symbol is changed to the code point of the fixed symbol sequence, and the input symbol is output without being changed except for the section of the fixed symbol sequence. The force symbol conversion circuit, in accordance with known modulation scheme, coding rate information between the transmitter and the Viterbi decoder performs Viterbi decoding corresponding to the modulation scheme and coding rate of each symbol output from the input symbol conversion circuit,
The modulation scheme / coding rate information of each symbol input to the Viterbi decoder is given to the Viterbi decoder, and when the modulation scheme and coding rate are switched, a fixed symbol for termination following the last symbol before switching is used. If a symbol sequence is included,
A Viterbi decoder control circuit that generates the symbol coordinate conversion signal and supplies the symbol coordinate conversion signal to the input symbol conversion circuit.

According to the eighteenth aspect of the present invention, the transmission frame is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and when the modulation scheme and the coding rate are switched, the transmission symbol is added to the last symbol before the switching. There is a case where a fixed symbol sequence for termination is included, information on the modulation scheme and coding rate of each symbol is included as transmission control information for each frame, and the symbol of each frame exceeds a different modulation scheme and coding rate. An error correction circuit for Viterbi-decoding a data sequence which has been convolutionally encoded and transmitted by one convolutional encoder continuously, and which converts a signal to be converted into demodulated I / Q data corresponding to a fixed symbol. When the symbol coordinate conversion signal is used, according to the symbol coordinate conversion signal, for the fixed symbol sequence input section, the input symbol is And the input symbol conversion circuit that outputs the input symbol without changing the input symbol except for the section of the fixed symbol sequence, and each symbol output from the input symbol conversion circuit according to the modulation scheme / coding rate information. A Viterbi decoder that performs Viterbi decoding corresponding to the modulation scheme and the coding rate of the above, a transmission control information decoding circuit that decodes the transmission control information included in each frame, and a decoding result output from the transmission control information decoding circuit. Thus, the modulation scheme / coding rate information of each symbol input to the Viterbi decoder is extracted and provided to the Viterbi decoder, and when the modulation scheme and coding rate are switched, the modulation scheme / coding rate is terminated following the last symbol before switching. When a fixed symbol sequence is included, a Viterbi decoder control circuit that generates the symbol coordinate conversion signal and provides the symbol coordinate conversion signal to the Viterbi decoder It is characterized in that it comprises a.

The invention of claim 19 of the present application is directed to claim 7,
In the error correction circuit according to any one of 8, 10, 17, and 18, the Viterbi decoder modulates a fixed symbol sequence when a signal specifying a branch in a state transition of a trellis diagram is a fixed branch signal. At the time of switching of the system and the coding rate, it is replaced with a configuration for performing Viterbi decoding that additionally supports the fixed branch signal. When a fixed symbol sequence for termination is included following the last symbol, Viterbi is used for the input fixed symbol sequence from the first symbol to the symbol for which the state of the convolutional encoder is determined. Of the branches output from each state in decoding, only one branch corresponding to the fixed symbol sequence is valid, and the other branches are valid. Add to generate even the fixed branch signal for disabling, it is characterized in that the replaced structure given to the Viterbi decoder.

The invention of claim 20 of the present application relates to claim 7,
In the error correction circuit according to any one of 8, 12, 13, 17, and 18, when the Viterbi decoder uses a signal for reducing the number of states of a trellis diagram for a fixed symbol sequence as a state reduction signal, At the time of switching of the system and the coding rate, the configuration is replaced with a configuration for performing Viterbi decoding that also supports the state reduction signal, and the Viterbi decoder control circuit is switched at the time of switching between the modulation scheme and the coding rate, before switching. When a fixed symbol sequence for termination is included following the last symbol, Viterbi is used for the input fixed symbol sequence from the first symbol to the symbol for which the state of the convolutional encoder is determined. Of all the states in decoding, only the state corresponding to the input up to that symbol is made valid, the other states are made invalid, and the state is set every time one symbol is input. Add to also generate the status reduction signal for reducing, it is characterized in that the replaced structure given to the Viterbi decoder.

The invention of claim 21 of the present application is directed to claim 7,
In the error correction circuit according to any one of 8, 17, and 18, the Viterbi decoder is configured to:
When a signal specifying a branch in a state transition of a trellis diagram is a fixed branch signal, and a signal for reducing the number of states in the trellis diagram is a state reduction signal, the fixed branch signal is used when a modulation method and a coding rate are switched. And a configuration for performing Viterbi decoding in which the state reduction signal is also added, and the Viterbi decoder control circuit is terminated at the time of switching the modulation scheme and the coding rate, following the last symbol before switching. If a fixed symbol sequence of
In the input fixed symbol sequence, from the first symbol to the symbol in which the state of the convolutional encoder is determined, one of the branches output from each state in Viterbi decoding corresponds to the fixed symbol sequence. Only one branch is valid, and the fixed branch signal for invalidating the other branches is generated. Of all the states in Viterbi decoding, only the state corresponding to the input of the symbol is valid, and other states are valid. A state in which the state is invalidated, and the state reduction signal for reducing the state each time one symbol is input is generated, and the configuration is given to the Viterbi decoder in addition to the confirmed state signal. It is.

The invention of claim 22 of the present application relates to claim 7,
In the error correction circuit according to any one of 8, 10, 12, 13, 17, and 18, when the Viterbi decoder uses a signal for reducing the number of states of a trellis diagram for a fixed symbol sequence as a state reduction signal At the time of switching between the modulation scheme and the coding rate, the configuration is replaced with a configuration for performing Viterbi decoding that also supports the state reduction signal. When a fixed symbol sequence for termination is included following the previous last symbol, in the input fixed symbol sequence, from the first symbol to the symbol for which the state of the convolutional encoder is determined, , Among all states in Viterbi decoding, to the minimum value that can take only the path metric of the state corresponding to the input up to that symbol,
To reset to the maximum value that can take another state, and after it is determined to be one state, to reset to the minimum value that can take only the path metric of the determined one state, and to the maximum value that can take another state Wherein the state reduction signal is generated and provided to the Viterbi decoder.

The invention of claim 23 of the present application is directed to claim 7,
8. The error correction circuit according to any one of 8, 10, 17, and 18, wherein the Viterbi decoder is configured such that a signal specifying a branch in a state transition of a trellis diagram for a fixed symbol sequence is a fixed branch signal, When the signal to reduce the number of states is a state reduction signal, at the time of switching of the modulation scheme and the coding rate, replaced with a configuration that performs Viterbi decoding that additionally supports the fixed branch signal and the state reduction signal, The Viterbi decoder control circuit, when switching the modulation scheme and the coding rate, if a fixed symbol sequence for termination is included following the last symbol before switching, in the fixed symbol sequence input, From the first symbol to the symbol for which the state of the convolutional encoder is determined, the branch output from each state in Viterbi decoding , The fixed branch signal for validating only one branch corresponding to the fixed symbol sequence and disabling the other branches, and the state corresponding to the input of up to the symbol out of all states in Viterbi decoding. It is reset to the minimum value that can take only the path metric, the maximum value that can take another state, and after it is determined to be one state, the other value is set to the minimum value that can take only the path metric of the determined one state. The method further includes generating the state reduction signal for resetting the state to the maximum possible value, and replacing the configuration with the configuration applied to the Viterbi decoder.

According to the invention of claim 24 of the present application, in the transmission format, a fixed-length data sequence of a minimum unit is set as a slot, and one frame = M slots and one superframe =
In the case where N frames are used, an error correction circuit for deinterleaving a data sequence transmitted after performing M interleavings of N depths in slot units in the superframe on the receiving side. When a signal for deinterleaving only the data of the selected L slot among the M slots is used as the slot selection signal, only the data of the L slot selected according to the slot selection signal is deinterleaved and the data is demultiplexed. A deinterleaving circuit to be output, and a tuning circuit that generates the slot selection signal according to tuning information and provides the generated signal to the deinterleaving circuit.

According to a twenty-fifth aspect of the present invention, in the error correction circuit of the twenty-fourth aspect, the de-interleave circuit sets the maximum number of slots per frame to be selected to L.
When max is used, two banks are used for the area of only the maximum (Lmax × N) slots of the memory circuit.

According to a twenty-sixth aspect of the present invention, in the error correction circuit according to the twenty-fourth aspect, the de-interleave circuit is configured to transmit L-slot data per frame, which is selected and de-interleaved, to L-format data. /
It is characterized by outputting continuously at a speed of M.

[0157] The invention of claim 27 of the present application is directed to a plurality of MPEs.
In a transmission method in which transmission is performed in a transmission format in which G transport streams are multiplexed, when a data sequence of each packet unit of an MPEG transport stream is a slot, and 1 frame = M slots and 1 superframe = N frames, The transport stream number information of each slot is included as transmission control information in the superframe. In the superframe, a data sequence transmitted by performing M interleavings with a depth of N for each slot is received. An error correction circuit for deinterleaving on the side, wherein when a signal for deinterleaving only data of a selected L slot out of M slots of each frame is used as a slot selection signal, the error correction circuit according to the slot selection signal L slot selected Deinterleaving circuit for deinterleaving only the data of each frame and outputting data, a transmission control information decoding circuit for decoding the transmission control information included in each frame, and a decoding output from the transmission control information decoding circuit Decoding the transport stream number information of each slot from the result, generating the slot selection signal according to the tuning information, and providing the generated signal to the de-interleave circuit. is there.

According to a twenty-eighth aspect of the present invention, in the error correction circuit according to the twenty-seventh aspect, the de-interleave circuit is configured so that one type of transport stream is occupied by one type.
Assuming that the maximum number of slots per frame is Lmax, an area 2 only for the maximum (Lmax × N) slots of the memory circuit
One type of transport selected using a bank
It is characterized in that data is output by deinterleaving only the stream.

According to a twenty-ninth aspect of the present invention, in the error correction circuit according to the twenty-seventh aspect, the de-interleave circuit has one type occupied by one type of transport stream.
Assuming that the maximum number of slots per frame is Lmax and K is an integer of 2 or more, the maximum of the memory circuit (Lmax × N × K)
Using the area 2 banks only for the slots, the selected K
It is characterized in that the data is output after deinterleaving the transport stream of the kind or less.

The invention according to claim 30 of the present application is the error correction circuit according to claim 27, wherein the de-interleave circuit converts L-slot data per frame selected and de-interleaved into L in the transmission format. /
It is characterized by outputting continuously at a speed of M.

According to a thirty-first aspect of the present invention, in the error correction circuit of the twenty-seventh aspect, the de-interleave circuit is configured so that the selected J types of transport streams each have L1, L2,. …, Lj
Assuming that the slot is occupied, a total of (L1 + L2 +
.. + Lj) Slot data is continuously output at a rate of (L1 + L2 +... + Lj) / M in the transmission format.

According to a thirty-second aspect of the present invention, in a transmission format, a fixed-length data sequence of a minimum unit is set as a slot, and one frame = M slots and one superframe =
When N frames are used, a data sequence that is continuously randomized and transmitted in units of the superframe is
An error correction circuit that performs de-randomization on the receiving side, wherein an already selected L among M slots of each frame is selected.
When a signal for performing de-randomization for each slot is used as a slot selection signal, (N × M) kinds of de-randomized data for each head data of (N × M) slots in one superframe are used. L which has an initial value and has already been selected according to the slot selection signal
When slot data is input, a de-randomizing circuit that performs de-randomization for each input slot from an initial value corresponding to each slot input according to the slot selection signal, and an M slot of each frame. Of the L slot data already selected and input to the de-randomizing circuit, the data
A channel selection circuit for generating the slot selection signal for performing randomization in accordance with channel selection information and providing the generated signal to the de-randomization circuit.

According to the invention of claim 33 of the present application, a plurality of MPEs
In a transmission method in which transmission is performed in a transmission format in which G transport streams are multiplexed, when a data sequence of each packet unit of an MPEG transport stream is a slot, and 1 frame = M slot and 1 superframe = N frame, The transport stream number information of each slot is included as transmission control information in the superframe, and the data sequence transmitted by being continuously randomized in the superframe unit is de-randomized on the receiving side. In the error correction circuit, when a signal for performing de-randomization for each slot is used as a slot selection signal for data of an already selected L slot among M slots of each frame, (N × M) for each head data of the slot When the data of the (L × L) randomized type and the data of the L slot already selected according to the slot selection signal is input, the initial value corresponding to each of the input slots is determined according to the slot selection signal. From the values, a de-randomization circuit that performs de-randomization for each input slot, a transmission control information decoding circuit that decodes the transmission control information included in each frame, and a signal output from the transmission control information decoding circuit From the decoding result, the transport stream number information of each slot is decoded, and among the M slots of each frame, the data of the L slot that is already selected and input to the de-randomizing circuit is de-decoded for each slot. The slot selection signal for performing randomization is generated according to channel selection information, and given to the de-randomization circuit. And a tuning circuit,
It is characterized by having.

According to a thirty-fourth aspect of the present invention, in a transmission format, a fixed-length data sequence of a minimum unit is set as a slot, and one frame = M slots and one superframe =
An error correction circuit that outputs only L-slot data per frame selected on the receiving side according to channel selection information when a transmitted data sequence is set to N frames on the receiving side. When a signal for continuously outputting the data of the L slot at the L / M speed of the transmission format is used as a slot selection signal,
By reading and writing only the data of the selected L slot to the memory circuit according to the slot selection signal,
A speed conversion circuit that continuously outputs L-slot data per selected frame at the L / M speed of the transmission format, and a data of the selected L-slot among the M slots of each frame in the transmission format. A channel selection circuit for generating the slot selection signal for continuously outputting at the L / M speed in accordance with channel selection information and supplying the slot selection signal to the speed conversion circuit.

According to a thirty-fifth aspect of the present invention, in the error correction circuit of the thirty-fourth aspect, the speed conversion circuit is configured so that the maximum number of slots per one frame is Lmax. It is characterized in that only the area is used.

[0166] The invention of claim 36 of the present application is directed to a plurality of MPEs.
In a transmission method in which transmission is performed in a transmission format in which G transport streams are multiplexed, when a data sequence of each packet unit of an MPEG transport stream is a slot, and 1 frame = M slot and 1 superframe = N frame, An error in which a data sequence transmitted by including transport stream number information of each slot as transmission control information in a superframe and outputting only L slot data per frame selected on the receiving side according to channel selection information. When a signal for continuously outputting data of a selected L slot out of M slots of each frame at a rate of L / M in a transmission format is used as a slot selection signal,
By reading and writing only the data of the selected L slot to the memory circuit according to the slot selection signal,
A speed conversion circuit for continuously outputting L-slot data per selected frame at the L / M speed of the transmission format, a transmission control information decoding circuit for decoding the transmission control information included in each frame, From the decoding result output from the transmission control information decoding circuit, transport stream number information of each slot is decoded, and data of L slots corresponding to the selected transport stream among the M slots of each frame is decoded. And a channel selection circuit for generating the slot selection signal for continuously outputting at the L / M speed of the transmission format in accordance with the channel selection information and supplying the slot selection signal to the speed conversion circuit. It is.

According to a thirty-seventh aspect of the present invention, in the error correction circuit of the thirty-sixth aspect, the speed conversion circuit is configured such that a maximum number of slots per frame occupied by one type of transport stream is Lmax. The present invention is characterized in that one type of selected transport stream is continuously output by using an area of only the maximum Lmax slots of the memory circuit.

According to a thirty-eighth aspect of the present invention, in the error correction circuit of the thirty-sixth aspect, the speed conversion circuit sets Lmax and K as the maximum number of slots per frame occupied by one type of transport stream. When an integer of 2 or more is used, an area of only the maximum (Lmax × K) slots of the memory circuit is used, and the selected K or less types of transport streams are continuously output. It is.

According to a thirty-ninth aspect of the present invention, in the error correction circuit of the thirty-sixth aspect, each of the J-type transport streams selected by the speed conversion circuit is one.
Assuming that L1, L2,..., Lj slots are occupied per frame, J types of transport streams are transmitted in L1 / M, L2 /
M,..., Lj / M.

According to the invention of claim 40 of the present application, in the error correction circuit of claim 24 or 25, in addition to the de-interleave circuit and the tuning circuit, L per one frame already selected according to the slot selection signal. The data sequence of the slot is input, and according to the slot selection information output from the channel selection circuit, the transmission format L
A speed conversion circuit for continuously outputting a data sequence at a speed of / M is provided.

According to a forty-first aspect of the present invention, in the error correction circuit according to the forty-ninth aspect, the speed conversion circuit is configured such that the maximum number of slots per frame selected is Lmax, and only the maximum number of slots of the memory circuit is Lmax. Is used.

The invention of claim 42 of the present application relates to claims 27 to
29. The error correction circuit according to claim 29, wherein
In addition to the interleave circuit, the transmission control information decoding circuit, and the channel selection circuit, the slot receives a data sequence of L slots per frame already selected according to the slot selection signal, and outputs the slot output from the channel selection circuit. A speed conversion circuit for continuously outputting a data sequence at the transmission format L / M speed according to the selection information is provided.

The invention of claim 43 of the present application is the error correction circuit of claim 42, wherein the speed conversion circuit is a memory, provided that the maximum number of slots per frame occupied by one type of transport stream is Lmax. Using the area of only the maximum Lmax slot of the circuit,
It is characterized by continuously outputting different types of transport streams.

According to a forty-fourth aspect of the present invention, in the error correction circuit of the forty-second aspect, the speed conversion circuit sets the maximum number of slots per frame occupied by one type of transport stream to Lmax and K to two. When the integer is equal to or more than the above, the area of only the maximum (Lmax × K) slots of the memory circuit is used, and K or less types of selected transport streams are continuously output. .

According to a forty-fifth aspect of the present invention, in the error correction circuit of the forty-second aspect, each of the J type transport streams selected by the speed conversion circuit is 1
Assuming that L1, L2,..., Lj slots are occupied per frame, J types of transport streams are transmitted in L1 / M, L2 /
M,..., Lj / M.

[0176]

(Embodiment 1) An error correction circuit according to Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of the error correction circuit 101 according to the present embodiment. In the error correction circuit 101 shown in FIG. 1, the blocks shown by thick solid lines are different from the conventional example, and the error correction circuit 2000 shown in FIG.
It is characterized in that a Viterbi decoder 102 controlled by a switching control signal is provided instead of one Viterbi decoder 200002, and a Viterbi decoder control circuit 103 for generating a switching control signal is added. The switching control signal is a signal for switching a symbol for determining the minimum path metric in the path memory when outputting the Viterbi decoded data at the time of switching the modulation scheme and the coding rate. The other blocks, that is, the high / low hierarchy selection signal generation circuit 20003 to the channel selection circuit 20011, are the same as those shown in FIG.

The error correction circuit 10 configured as described above
Each block and its operation will be described below. However, since the operation after the output of the Viterbi decoder 102 is the same as that of the conventional example, the description thereof is omitted.

FIG. 2 shows a Viterbi decoder 102 according to the present embodiment.
Is a block diagram showing the configuration of the first embodiment, and also shows a Viterbi decoder control circuit 103. Blocks different from those in the conventional example are indicated by thick solid lines, and such an illustration method is adopted in all block diagrams described below. The Viterbi decoder 102 shown in FIG. 2 includes a de-punctured S / P circuit 20.
016 and a Viterbi decoding circuit 104 indicated by a dotted line. The Viterbi decoding circuit 104 includes a branch metric calculation circuit 20018, an ACS circuit 105, a path metric memory 20082, and a path memory 20021.
And Viterbi decoder 102 of the present embodiment
Is different from the conventional Viterbi decoder 20002 shown in FIG. 100 only in the internal configuration of the ACS circuit 105.

With respect to the problem to be solved by the invention described with reference to FIG. 118, a Viterbi decoding control method according to the present embodiment when the transmission mode is switched will be described. FIG. 3 shows the path memory 2 in the Viterbi decoder 102 when the transmission mode is switched.
FIG. 3 is a trellis diagram showing a state of 0021 (path memory length = J). FIG. 3A is a trellis diagram when the last symbol of the transmission mode A is input to the path memory 20021. FIG. 3B shows the first transmission mode B
FIG. 17 is a trellis diagram at the time when a symbol is input to the path memory 20021. FIG. 3C is a trellis diagram at the time when up to the next (J-2) symbol of the transmission mode B is input to the path memory 20021.

As shown in FIG. 1, in error correction circuit 101 of the present embodiment, transmission control information decoding circuit 200
The transmission mode / slot information of FIG. 82 decoded in 10 is output to the Viterbi decoder control circuit 103. The Viterbi decoder control circuit 103 recognizes a transmission mode switching symbol based on the input transmission mode / slot information. The Viterbi decoder control circuit 103 stores the path memory 20021 up to the last symbol in the transmission mode A in FIG.
The switching control signal is generated and output to the ACS circuit 105 from the time when it is input to the path memory 22021 until the time when the (J-1) symbol of the transmission mode B in FIG.

The ACS circuit 105 uses the switching control signal output from the Viterbi decoder control circuit 103 to control the path metric memory 20020 and the path memory 2020 as follows.
021 is performed. That is, as shown in FIG. 3A, when up to the last symbol of the transmission mode A is input to the path memory 20021, the same as in the normal Viterbi decoding,
The state having the smallest path metric is determined among all the states of the latest symbol input to the path memory 20021, that is, the J-th symbol in the path memory 20021. The surviving path input to the state is (J-1)
Returning to the previous symbol, the first symbol in the corresponding path memory 20021 is output as Viterbi decoded symbol data.

Next, as shown in FIG. 3B, when the first symbol of the transmission mode B is input to the path memory 20021, a normal ACS operation is performed to branch to generate the latest trellis diagram. Is extended by one symbol. However, the state determined as the minimum path metric at the time of FIG.
1) The surviving path input to the symbol
-2) Returning to the symbol memory, and returning to the corresponding path memory 200
21 is output as Viterbi decoded symbol data.

Hereinafter, during the period in which the unoutput data of the transmission mode A remains in the path memory 22021, the transmission mode A
Of the last symbol of the last symbol, returns to the state before the surviving path input to the state determined as the minimum path metric, and outputs the first symbol in the corresponding path memory 20021 as Viterbi decoded symbol data.

FIG. 3C shows a trellis diagram at the time when the (J-2) symbol in the transmission mode B is input to the path memory 20021 further than in FIG. 3B. At this point,
The last symbol in the transmission mode A corresponds to the first symbol in the path memory 20021, and Viterbi decoded data corresponding to the state determined as the minimum path metric is output from the path memory 20021.

As shown in FIG. 3C, when the next symbol of the transmission mode B is input to the path memory 20021,
Since all the data in the path memory 20021 are transmission mode B symbols, the normal Viterbi decoding output method is restarted. The state having the smallest path metric is determined among all the states of the latest symbol input to the path memory 20021, that is, the J-th symbol in the path memory 20021. The surviving path input to that state is (J
-1) Returning to the previous symbol position, and
21 is output as Viterbi decoded symbol data. The Viterbi decoder 102 performs the same operation as the Viterbi decoder 20002 shown in the conventional example except for the control at the time of switching the transmission mode described above, and outputs Viterbi decoded data.

With the configuration described above, the error correction circuit 101 of the present embodiment completely shuts off the effect of the transmission mode B after the mode switching, and the mode remaining in the path memory 20021 when the transmission mode is switched. Transmission mode A before switching
Can be output.

Also, in the present embodiment, the Viterbi decoder control circuit 103 generates a switching control signal as described below, and the ACS circuit 105 causes the Viterbi decoder control circuit 103
In response to the output switching control signal, the path metric memory 2008 and the path memory 2002 as shown in FIG.
1 may be performed. In this case, the Viterbi decoder control circuit 103 in FIG.
The transmission mode switching symbol is recognized based on the transmission mode / slot information output from the. As shown in FIG. 4A, a switching control signal is generated and output to the ACS circuit 105 only when the last symbol of the transmission mode A is input to the path memory 20021.

As shown in FIG. 4A, when up to the last symbol of the transmission mode A is input to the path memory 20021, the ACS circuit 105 performs the same operation as the normal Viterbi decoding. , That is, the state having the smallest path metric among all the states of the J-th symbol in the path memory 20021 is determined. Then, the path metric memory 200 is set so that only that state is valid and all other states are invalid.
20 and the path memory 20021 are controlled.

In other respects, decoding similar to that of the Viterbi decoding shown in the conventional example is performed. The state having the minimum path metric is determined among all the states of the latest symbol input, that is, the J-th symbol in the path memory 20021. The surviving path input in that state is returned by (J-1) symbols before the first path in the corresponding path memory 20021.
Output the ith symbol as Viterbi decoded symbol data.

According to the configuration described above, the last symbol in transmission mode A before transmission mode switching is performed as shown in FIG.
In the trellis diagrams shown in (a) to (c), only one state having the minimum path metric is valid. Therefore,
The error correction circuit 101 of the present embodiment completely shuts off the influence of the transmission mode B after the mode switching, and retains the Viterbi decoded data of the transmission mode A before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching. Can be output.

It should be noted that FIGS. 3A to 3C or FIG.
At the time point (a), the Viterbi decoder control circuit 103 generates a switching control signal. However, the switching control signal may be generated only when the modulation multi-level number after the transmission mode switching is larger than before the transmission mode switching or when the modulation multi-level number is the same and the coding rate is high. For example, in the transmission frame shown in FIG.
(BPSK: r = 1/2) → Next transmission mode (TC-8
Only when the transmission mode of PSK: r = ２ or QPSK: r = ３ or QPSK: r = １ ／) is switched, the Viterbi decoder control circuit 103 may generate a switching control signal. Good. However, TMCC (BPSK:
r = 1/2) → Excluding the case of BPSK (r = 1/2).

The transmission control signal generated by the Viterbi decoder control circuit 103 determines the transmission mode A before the transmission mode switching.
Is decoded at the last symbol as shown in FIG. However, for example, the main signal T
C-8PSK (r = 2/3) → QPSK (r = 3/4)
When the transmission mode is switched, TC-8PSK (r =
QPSK (r = 3/4) following the last symbol of 2/3)
The symbol of TC-8PSK (r =
2/3) is larger than the code point distance. Therefore, if normal Viterbi decoding is performed without terminating continuously from the first symbol of QPSK (r = 3/4), a more reliable branch metric of QPSK (r = 3/4) is generated, and termination is performed. Are performed, TC-8PSK (r =
It can be expected that the BER for (J-1) symbols of (2/3) is reduced.

As shown in FIG. 87, TMCC (BP
Before and after (SK: r = 1/2), a fixed symbol sequence of 2 bytes at a time and 20 symbols at the input of the Viterbi decoder 102 exists as a TAB signal (w1, w2, w3). Therefore, at the time of transmission mode switching before and after TMCC (BPSK: r = １ ／), the Viterbi decoder control circuit 103 may be configured not to generate a switching control signal. In this case, a Viterbi decoding control method using the property of the fixed symbol sequence can be considered. This will be described in Embodiments 2 and 3.

(Embodiment 2) An error correction circuit according to Embodiment 2 of the present invention will be described with reference to the drawings. FIG. 5 shows an error correction circuit 201 according to this embodiment.
FIG. 3 is a block diagram showing the configuration of FIG. In the error correction circuit 201 shown in FIG. 5, the blocks shown by thick solid lines are different from the conventional example, and the Viterbi decoder 200002 of the error correction circuit 20001 shown in FIG. 202 is provided, and a Viterbi decoder control circuit 203 for generating a fixed state signal is added. The fixed state signal is a signal indicating a period during which the state of the convolutional encoder is fixed for the fixed symbol sequence. The other blocks, that is, the high / low hierarchy selection signal generation circuit 20003 to the channel selection circuit 20011, are the same as those shown in FIG.

The error correction circuit 20 constructed as described above
Each block 1 and its operation will be described. However,
The operation after the output of the Viterbi decoder 202 is the same as that of the conventional example, and the description is omitted.

FIG. 6 shows a Viterbi decoder 202 according to the present embodiment.
And a Viterbi decoder control circuit 203 is also shown. The Viterbi decoder 202
It has a depunctured S / P circuit 20066 and a Viterbi decoding circuit 204 indicated by a dotted line. The Viterbi decoding circuit 204 includes a branch metric calculation circuit 200
18, the ACS circuit 205, and the path metric memory 2
0020 and a path memory 20021. The Viterbi decoder 202 according to the present embodiment differs from the conventional Viterbi decoder 20002 shown in FIG. 100 only in the internal configuration of the ACS circuit 205.

With respect to the problem to be solved by the invention described with reference to FIG. 118, the Viterbi decoding control according to the present embodiment at the time of transmission mode switching, in particular, a control method utilizing the property of a fixed symbol sequence of a TAB signal will be described. This will be described below. FIG. 7 shows, for example, TMCC (BP
SK: r = 1/2) → Path memory 20021 in Viterbi decoder 202 in transmission mode B (path memory length =
It is a trellis diagram which shows the situation of J).

In particular, FIG. 7 (a) shows TMCC (BPSK:
r = １ ／) 32 symbols after the TAB signal, for example, w2 = xxx0B677h or w3 = x shown in FIGS.
In the xxF4988h, up to the first symbol out of 20 symbols in which the state of the convolution circuit 10014 is determined is the path memory 2
FIG. 3 is a trellis diagram at the time when the data is input to 0021. The convolution circuit 10014 of the above TAB signal
The 20 symbols that determine the state of
After S / P conversion by the S / P circuit 2006, it corresponds to 10 symbols.

FIG. 7B is a trellis diagram when the next symbol (after S / P conversion) of the subsequent TAB signal is input to the path memory 20021. Further, FIG.
Is the first (J-1) of the transmission mode B following the remaining symbols (8 symbols after S / P conversion) of the rear TAB signal.
0) Trellis diagram at the time when a symbol is input to path memory 20021.

In the error correction circuit 201 of the present embodiment, as in the first embodiment, the transmission control information decoding circuit 2
The transmission mode / slot information decoded in 0010 is output to the Viterbi decoder control circuit 203.

The Viterbi decoder control circuit 203 recognizes a TAB signal (w1, w2, w3) which is a fixed sequence symbol, based on the transmission mode / slot information output from the transmission control information decoding circuit 20010. As shown in FIG. 7A, the tenth symbol of each TAB signal is stored in the path memory 200 starting from the time when the first symbol of the ten symbols of each TAB signal after S / P conversion is input to the path memory 20021.
Until the time when the signal is input to 21, the final state signal is generated and A
Output to the CS circuit 205.

The ACS circuit 205 in FIG. 6 controls the path metric memory 20020 and the path memory 22021 in the following manner based on the determined state signal output from the Viterbi decoder control circuit 203. That is, TAB after one symbol before TMCC (BPSK: r = 1/2) in FIG.
32 symbols, w2 = xxx0B677h or w3 = xx
In xF4988h, up to one symbol before 20 symbols in which the state of the convolution circuit 10014 is determined is stored in the path memory 20.
Until the time when the signal is input to the path memory 021, the ACS circuit 205 determines the minimum symbol among all the states of the latest symbol input to the path memory 20021, that is, the J-th symbol in the path memory 20021 as in the normal Viterbi decoding. Is determined. Then, the surviving path input in this state is returned by (J-1) symbols before,
The first symbol in the corresponding path memory 20021 is output as Viterbi decoded symbol data.

Next, when the first symbol of the 20 symbols in the rear TAB signal (w2 or w3) at which the state of the convolution circuit 10014 is determined is input to the path memory 22021, only the determined one state is valid. And the path metric memory 20 so that all other states are invalidated.
020 and the path memory 20021 are controlled.

As shown in FIG. 7B, the rear TAB signal (w
Similarly, at the time when the next symbol of 2 or w3) is input to the path memory 22021, the path metric memory 20020 and the path memory 20021 are set so that only the determined one state is valid and all other states are invalid. Control. The same control is performed until the remaining symbol of the subsequent TAB signal is input.

Next, when the first symbol of the transmission mode B is input, decoding similar to the Viterbi decoding shown in the conventional example is performed. The latest symbol input, that is, the path memory 200
Among all states of the J-th symbol in 21, the state having the smallest path metric is determined. The surviving path input to that state is returned by (J-1) symbols, and the first symbol in the corresponding path memory 20021 is output as Viterbi decoded symbol data. FIG. 7C shows the first (J-10) of the transmission mode B.
The time points up to the symbol are input to the path memory 20021.

The above is the rear TAB signal (w2 or w3)
Is a Viterbi decoding control method using the property of the fixed symbol sequence in the above, but the same control can be performed for the previous TAB signal (w1).

The Viterbi decoder 202 performs the above-described transmission mode switching, that is, TMCC (BPSK: r = 1).
/ 2) → Except for the control of the transmission mode B, the same operation as that of the Viterbi decoder 20002 shown in the conventional example is performed to output Viterbi decoded data.

With the configuration described above, Viterbi decoding control using the property of the fixed symbol sequence in the TAB signal (w2 or w3) after the TMCC (BPSK: r =＝) before the transmission mode switching is performed. ing. Therefore, the error correction circuit 201 of the present embodiment completely shuts off the influence of the transmission mode B after the mode switching, and sets the TMCC (BPSK: r = 1/2) Viterbi decoded data can be output.

For the fixed symbol sequence of 20 symbols (10 symbols after S / P conversion) of the rear TAB signal (w2 or w3), correct Viterbi decoded data is always selected by the above control method. As a result, as shown in FIG. 7A, when the first symbol of the rear TAB signal (w2 or w3) is input to the path memory 20021, the TMCC (BPSK: r
= 1/2) (J-1) It is possible to reduce the symbol error rate.

[0210] The same Viterbi decoding control is also performed for 20 symbols of the fixed symbol sequence of the previous TAB signal (w1), so that TMCC (BPSK: r = 1/2) is obtained.
Transmission mode TC-8PSK (r = 2 /
3) or QPSK (r = 3/4, 1/2) or BPSK
(R = １ ／).

As described above, the error correction circuit 201 according to the present embodiment includes the front TAB signal (w1) and the rear TAB signal (w1).
20 fixed symbol sequences for each signal (w2 or w3)
By performing a Viterbi decoding control method using symbols (10 symbols after S / P conversion), 128 symbols (S / P) of real symbol data of TMCC (BPSK: r = 1/2) shown in FIG. For 64 symbols after conversion), the influence of symbols in the previous and subsequent transmission modes can be completely cut off, and the error correction capability of convolutional coding inherent in BPSK (r = 1/2) can be brought out. .

In this embodiment, the Viterbi decoder control circuit 203 has 20 symbols for each TAB signal (w1, w2, w3) (10 symbols after S / P conversion) as shown in FIG. Of the path memory 2002
1, the tenth symbol (the last symbol after S / P conversion) of each TAB signal is stored in the path memory 200.
21 until the time when it is input to
The output is provided to the CS circuit 205. Instead,
The Viterbi decoder control circuit 203 outputs, for example, each TAB signal 2
A configuration may be adopted in which a determined state signal is generated only when the first symbol of 0 symbols (10 symbols after S / P conversion) is input to the path memory 20021 and output to the ACS circuit 205. With this configuration, control of the Viterbi decoder control circuit 203 and the ACS circuit 205 can be simplified. The first symbol of each TAB signal (S / P
For the converted final symbol), only one determined state is valid in the trellis diagram shown in FIG.
All other states are invalidated, so at least TMCC
(BPSK: r = 1/2) It is possible to cut off the influence of symbols in the transmission mode before and after.

In the above description, the Viterbi decoder control circuit 20
No. 3 generates a definite state signal only when the first symbol of the 20 symbols of each TAB signal is input to the path memory 20021 and outputs it to the ACS circuit 205, for example. However, as shown in FIGS. 7A to 7C, after the S / P conversion, the symbol period for generating the fixed state signal is 1
It is possible to arbitrarily select any number of symbols up to a maximum of 10 symbols, and it is also arbitrary which symbol is selected.

(Embodiment 3) An error correction circuit according to Embodiment 3 of the present invention will be described with reference to the drawings. FIG. 8 shows an error correction circuit 301 according to this embodiment.
FIG. 3 is a block diagram showing the configuration of FIG. In the error correction circuit 301 shown in FIG. 8, a block shown by a thick solid line is different from the conventional example, and a Viterbi decoder 302 controlled by a fixed branch signal is used instead of the Viterbi decoder 200002 of the error correction circuit 20001 of FIG. And a Viterbi decoder control circuit 303 for generating a fixed branch signal is added. The fixed branch signal is a signal that specifies a branch in a state transition of a trellis diagram for a fixed symbol sequence. Other blocks, that is, the high / low hierarchy selection signal generation circuit 20003 to the channel selection circuit 20011
Is the same as that shown in FIG.

The error correction circuit 30 configured as described above
Each block 1 and its operation will be described. However,
The operation after the output of the Viterbi decoder 302 is the same as that shown in the conventional example, and the description is omitted.

FIG. 9 shows a Viterbi decoder 302 according to the present embodiment.
And a Viterbi decoder control circuit 303 is also shown. The Viterbi decoder 302
It has a depunctured S / P circuit 20066 and a Viterbi decoding circuit 304 indicated by a dotted line. The Viterbi decoding circuit 304 includes a branch metric calculation circuit 200
18, the ACS circuit 305, and the path metric memory 2
0020 and a path memory 20021. The Viterbi decoder 302 of the present embodiment is different from the Viterbi decoder 20002 of the prior art shown in FIG.
Only the internal configuration of No. 5 has changed.

With respect to the problem to be solved by the invention described with reference to FIG. 118, the Viterbi decoding control method according to the present embodiment when the transmission mode is switched, particularly, the control method using the property of the fixed symbol sequence of the TAB signal This will be described below.

FIG. 10 is a trellis diagram showing a branch output method in Viterbi decoding. Here, QPSK (r = 3) where the Viterbi decoded symbol is 1 symbol = 1 bit
/ 4,）) or BPSK (r = １ ／). FIG. 10A is a trellis diagram showing a branch output method in the conventional Viterbi decoding.
At time t, two branches corresponding to decoded estimated symbols "1" and "0" are output from each state. FIG.
As shown in (a), at time (t + 1), there are two branches input to the state S, and the Viterbi decoder 20002 shown in the conventional example has the branch having the smallest path metric (shown by a thick line). Was the surviving path.

On the other hand, FIG. 10B is a trellis diagram showing a branch output method in the Viterbi decoding of the present embodiment for a TAB signal. For example, the rear TAB signal (w2 = xxx0B677h, decoded data W2 = A340h) is shown in FIG.
Is input to the Viterbi decoder 302, it is known whether the decoded estimated symbols are “1” or “0” for a total of 16 decoded estimated symbols. For example, the first symbol = "1". Therefore, FIG.
As shown in (b), for example, for the first symbol of the rear TAB signal (w2), at time t, only one branch corresponding to the decoded estimated symbol “1” is output from each state. At time (t + 1), only one branch is input to the state S, and the surviving path is automatically determined as indicated by the thick line in FIG.

When FIG. 10 (a) is compared with FIG. 10 (b), in FIG. 10 (b), for the TAB signal section, one branch from each state, for example, the decoded estimated symbol =
Since only the branch corresponding to “1” is output, the branch input to each state at time (t + 1) is the branch corresponding to the decoded estimated symbol = “1”, which automatically determines the surviving path. . Therefore, an erroneous sequence in the TAB signal section is not used as a surviving path, and the influence of the transmission mode B following the TMCC (BPSK: r = １ ／) is cut off and remains in the path memory 20021 when the transmission mode is switched. It can output the TMCC Viterbi decoded data. On the other hand, in FIG.
Without using the property of the fixed symbol sequence of the TAB signal, at time (t + 1), there are two branches input to each state, and a branch corresponding to an erroneous decoded estimation symbol may be selected as a surviving path. There is.

Here, a Viterbi decoding control method in the TAB signal section (fixed sequence section) shown in FIG. 10B will be described below. In error correction circuit 301 of FIG. 8, transmission control information decoding circuit
82 is output to the Viterbi decoder control circuit 303. The Viterbi decoder control circuit 303 uses the transmission mode / slot information to determine a fixed sequence symbol (TAB signal: w1, w2, w
Recognize 3). A fixed branch signal is generated from the time when the first symbol of each 16 symbols of the TAB signal is input to the path memory 20021 to the time when the 16th symbol of each TAB signal is input to the path memory 20021, and the ACS is generated.
Output to the circuit 305.

The ACS circuit 305 outputs only one branch corresponding to the fixed sequence = “1” or “0” from each state of the trellis diagram by the fixed branch signal output from the Viterbi decoder control circuit 303. Path metric memory 2008 and path memory 2002
1 is performed.

The Viterbi decoder 302 performs the above-described transmission mode switching, that is, TMCC (BPSK: r = 1
/ 2) → Except for the control of the transmission mode B, the same operation as that of the Viterbi decoder 20002 shown in the conventional example is performed to output Viterbi decoded data.

With the configuration described above, Viterbi decoding control utilizing the property of the fixed symbol sequence of the TAB signal (w2, w3) after the TMCC (BPSK: r = 1/2) before the transmission mode switching is performed. Therefore, the error correction circuit 301 of the present embodiment blocks the influence of the transmission mode B after the mode switching, and removes the TMCC (BPSK: r =
1/2) Viterbi decoded data can be output.

As a result, assuming that the path memory length = J, the TMCC (BPSK: r = TM) remaining in the path memory when the first symbol of the rear TAB signal (w2, w3) is input to the path memory 20021. 1/2) (J-
1) The symbol error rate can be reduced. Also, the same Viterbi decoding control is performed on the fixed symbol sequence 16 symbols of the previous TAB signal (w1), so that the transmission mode before the mode switching of TMCC (BPSK: r = １ ／), that is, TC-8PSK ( r = ２) or QPSK (r =＝,）) or BPSK (r =
1/2) can be blocked.

As described above, the error correction circuit 301 according to the present embodiment uses the front TAB signal (w1) and the rear TAB signal (w1).
The fixed symbol sequences of the signals (w2, w3) are 16
By performing the Viterbi decoding control method using symbols, TMCC (BPSK:
For 128 symbols of real symbol data (r = １ ／) (64 symbols after S / P conversion), the influence of the symbols in the previous and next transmission modes is cut off, and BPSK (r = 1 /
The error correction capability of the convolutional coding inherent in 2) can be brought out.

(Embodiment 4) An error correction circuit according to Embodiment 4 of the present invention will be described with reference to the drawings. FIG. 11 shows an error correction circuit 40 according to the present embodiment.
1 is a block diagram showing a configuration of FIG. In the error correction circuit 401 shown in FIG. 11, the blocks shown by thick solid lines are different from the conventional example, and the Viterbi decoder 402 controlled by the state reduction signal is used instead of the Viterbi decoder 200002 of the error correction circuit 20001 of FIG. And a Viterbi decoder control circuit 403 for generating a state reduction signal is added. The state reduction signal is a signal for reducing the number of states of a trellis diagram for a fixed symbol sequence. Other blocks, that is, high / low hierarchical selection signal generation circuit 200
03 to FIG. 9 that the tuning circuit 20011 is provided.
8 is the same as that shown in FIG.

The error correction circuit 40 configured as described above
Each block 1 and its operation will be described. However,
The operation after the output of the Viterbi decoder 402 is the same as that of the conventional example, and the description is omitted.

FIG. 12 shows a Viterbi decoder 40 according to the present embodiment.
2 is a block diagram showing the configuration of the second embodiment, and also shows a Viterbi decoder control circuit 403. FIG. Viterbi decoder 402
Has a depunctured S / P circuit 20066 and a Viterbi decoding circuit 404 indicated by a dotted line. The Viterbi decoding circuit 404 includes a branch metric calculation circuit 2
0018, an ACS circuit 405, a path metric memory 20080, and a path memory 20021. The Viterbi decoder 402 of the present embodiment is different from the Viterbi decoder 20002 of the conventional example in that the ACS circuit 4
Only the internal configuration of 05 has changed.

With respect to the problem to be solved by the invention described with reference to FIG. 118, the Viterbi decoding control method according to the present embodiment at the time of transmission mode switching, and in particular, a control method utilizing the property of a fixed symbol sequence of a TAB signal explain. FIG. 13 is an explanatory diagram showing a method for reducing the state of a trellis diagram according to the present embodiment. □ in the figure indicates each register of the convolution circuit 10014 shown in FIG. 91. For example, the rear TAB signal (w2 = xxx0B677h, W2 = A340h)
Is input to each register.

In FIG. 13, 1 of the rear TAB signal w2 is
Until immediately before six symbols are input to the Viterbi decoding circuit 404, the contents of all six registers of the convolution circuit 10014 are indeterminate.
It is 64 as shown in FIG. When the first symbol of w2 is input to the Viterbi decoding circuit 404, the content of the first register is determined to be "1", and the number of states is as shown in FIG.
To 32. Next, when the second symbol of w2 is input to the Viterbi decoding circuit 404, the contents of the first two registers are determined to be "01", so that the number of states is reduced to 16 as shown in FIG. You.

Hereinafter, the Viterbi decoding circuit 4 for one symbol at a time
When the number of states is halved every time the data is input to the register 04, and when up to the sixth symbol of w2 is input to the Viterbi decoding circuit 404, the contents of all six registers are determined to be "000101". The state is determined as shown in FIG. Hereafter, w
Until the second sixteenth symbol is input, only the determined one state is valid, and the Viterbi decoding circuit 404 performs Viterbi decoding.

By the way, in the second embodiment, as shown in FIG. 7, for only the last 10 symbols of w2, for example, only the determined one state is valid and Viterbi decoding is performed. In comparison, in the present embodiment, for example,
Only one state in which the symbol is determined is valid, and the first 6
Viterbi decoding circuit 4 for each symbol
The number of states is reduced by half each time the information is input to the address 04. Therefore, for all 16 symbols of the TAB signal (after S / P conversion), the Viterbi decoding control at the time of transmission mode switching is performed using the property of the fixed sequence.

Here, a method of implementing Viterbi decoding control in the TAB signal section (fixed sequence section) shown in FIG. 13 will be described. In the error correction circuit 401 of the present embodiment, the transmission mode / slot information decoded by the transmission control information decoding circuit 20010 is output to the Viterbi decoder control circuit 403 as in the first embodiment. The Viterbi decoder control circuit 403 uses the transmission mode / slot information to generate a fixed sequence symbol (TAB signal: w1, w
2, w3) is recognized. Since the first symbol of the 16 symbols of each TAB signal is input to the path memory 22021, the 16th symbol of each TAB signal is
021 and generate a state reduction signal until A
Output to the CS circuit 405.

The ACS circuit 405 halves the number of states by one symbol for each of the first six symbols of each TAB signal in accordance with the state reduction signal output from the Viterbi decoder control circuit 403 as described above. Controls the path metric memory 20082 and the path memory 20021 so that only one determined state is valid. Also, the Viterbi decoder 402 performs the above-described transmission mode switching, that is, TMCC (BPSK: r = 1 /
2) Except for the control of the transmission mode B, the same operation as that of the conventional Viterbi decoder 20002 is performed to output Viterbi decoded data.

With the configuration described above, Viterbi decoding control using the fixed symbol sequence property of the TAB signal (w2, w3) after the TMCC (BPSK: r = 1/2) before the transmission mode switching is performed. Therefore, the error correction circuit 401 of the present embodiment blocks the influence of the transmission mode B after the mode switching, and removes the TMCC (BPSK: r =
1/2) Viterbi decoded data can be output.

As a result, the rear TAB signal (w2, w3)
Of the TMCC (BP) remaining in the path memory when the first symbol of
SK: r = 1/2) (J-1) It is possible to reduce the symbol error rate. Also, by performing the same Viterbi decoding control on the fixed symbol sequence 16 symbols of the previous TAB signal (w1), TMCC (BPSK: r
= １ ／) transmission mode before mode switching, ie, TC-8
PSK (r = ２) or QPSK (r = ３, 1 /
2) or the effect of BPSK (r = １ ／) can be cut off.

As described above, the error correction circuit 401 according to the present embodiment uses the front TAB signal (w1) and the rear TAB signal (w1).
By performing a Viterbi decoding control method using 16 symbols (after S / P conversion) of each of the fixed symbol sequences of the signals (w2, w3), the TMCC (B) shown in FIG.
For 128 symbols of real symbol data (PSK: r = １ ／) (64 symbols after S / P conversion), the influence of the symbols in the previous and next transmission modes is cut off, and BPSK (r
= １ ／), which can bring out the inherent error correction capability of convolutional coding.

Further, as shown in FIG. 13, the number of states is reduced by half each time the leading six symbols are input to the path memory 20021 one by one. Therefore, TAB
This means that the Viterbi decoding control at the time of transmission mode switching is performed using the property of the fixed sequence for all 16 symbols of the signal, and the TMCC (BP
(SK: r = １ ／) real symbol data error rate can be further reduced.

(Embodiment 5) An error correction circuit according to Embodiment 5 of the present invention will be described with reference to the drawings. FIG. 14 shows an error correction circuit 50 according to the present embodiment.
1 is a block diagram showing a configuration of FIG. This error correction circuit 5
01, the block shown by the thick solid line is different from the conventional example, and the error correction circuit 20001 shown in FIG.
The feature is that a Viterbi decoder control circuit 503 for generating a symbol coordinate conversion signal and an input symbol conversion circuit 506 controlled by the symbol coordinate conversion signal are added. The symbol coordinate conversion signal is a signal to be converted into demodulated I / Q data corresponding to a fixed symbol. The other blocks, that is, the Viterbi decoder 20002 and the high / low hierarchical selection signal generation circuit 20003 to the channel selection circuit 20011, are the same as those shown in FIG.

The error correction circuit 50 constructed as described above
Each block 1 and its operation will be described. However,
Regarding the operation after the output of the Viterbi decoder 20002,
Since it is as shown in the conventional example, the description is omitted.

FIG. 15 is a block diagram showing the configuration of the Viterbi decoder 20002 and the connection relationship between the Viterbi decoder 20002 and the Viterbi decoder control circuit 303 and the input symbol conversion circuit 506. Viterbi decoder 20 of the present embodiment
002 is the same as the configuration of the conventional Viterbi decoder in FIG.

With respect to the problem to be solved by the invention described with reference to FIG. 118, the Viterbi decoding control method according to the present embodiment at the time of transmission mode switching, particularly a control method utilizing the property of a fixed symbol sequence of a TAB signal explain.
In the error correction circuit 501 of the present embodiment, similarly to the first embodiment, the transmission mode / slot information decoded by the transmission control information decoding circuit 20010 is output to the Viterbi decoder control circuit 503. Viterbi decoder control circuit 503
Recognizes TAB signals (w1, w2, w3), which are fixed sequence symbols, based on the transmission mode / slot information. As shown in FIG. 87 or FIG. 108, the TMCC (BP
SK: 32 symbols (w
2 = xxx0B677h or w3 = xxxF4988h), for the section in which the last 20 symbols in which the state of the convolution circuit 10014 is determined are input to the input symbol conversion circuit 506, a symbol coordinate conversion signal is generated and the input symbol conversion circuit is generated. 506.

In accordance with the symbol coordinate conversion signal output from Viterbi decoder control circuit 503, input symbol conversion circuit 506 converts the last 20 symbols in which the state of convolution circuit 10014 is determined into I / Q data of the code point. , For other input symbols,
The Q data is output to the Viterbi decoder 20002.

As shown in FIG. 87 or FIG.
Convolution circuit 1001 of 32 symbols (w1 = xxxECD28h) of the TAB signal before C (BPSK: r =＝)
The input symbol conversion circuit 506 performs similar I / Q coordinate conversion on the last 20 symbols in which the state of 4 is determined.

I / O in input symbol conversion circuit 506
FIG. 16 shows how the Q data is converted. The input symbol conversion circuit 506 sets the I / Q coordinates of the input symbol output from the PSK demodulator (not shown) to "0" for the last 20 symbols of the TAB signal for which the state of the convolution circuit 10014 is determined. "Or" 1 "
Is converted to I / Q coordinate data of a code point of "0" or "1" depending on whether the symbol is a fixed symbol of "1" or "1". The Viterbi decoder 20002 performs Viterbi decoding in the same manner as in the conventional example, and outputs Viterbi decoded data to the symbol / byte conversion circuit 20004.

As described above, for the last 20 symbols of the TAB signal for which the state of the convolution circuit 10014 is determined, the I / Q coordinates whose code point and distance are 0 are input to the Viterbi decoder 20002. become. That is, in the Viterbi decoding trellis diagram, the convolution circuit 100
For the last 20 symbols in which the 14 states are determined, the branch metric input to the correct 1 state of the converted code point is 0, and all other states generate very large branch metrics. In such a decoding method, FIG.
It can be considered that control equivalent to the Viterbi decoding control method according to the second embodiment shown in (a) to (c) is being performed. That is, the value of the branch metric input to all the other states is much larger than the value of the branch metric input to the determined one state (the state of the converted code point). The minimum path metric will be automatically determined.

As described above, the error correction circuit 501 according to the present embodiment uses the front TAB signal (w1) and the rear TAB signal (w1).
20 fixed symbol sequences for each signal (w2 or w3)
By performing the Viterbi decoding control method using the symbols, the influence of the symbols in the previous and subsequent transmission modes on the TMCC (BPSK: r = 1/2) real symbol data, ie, the 128 symbols shown in FIG. It is possible to completely shut off the signal and to bring out the error correction capability of the convolutional coding inherent in BPSK (r = 1/2).

In the present embodiment, the Viterbi decoder 2000
Since the input symbol conversion circuit 506 is provided in the stage preceding the second symbol, the conventional Viterbi decoder can be used as it is for the Viterbi decoder 20002 in FIG.

The function (effect) of the error correction circuit 501 of this embodiment was examined by simulation. FIG. 17 is a configuration diagram of a transmission frame used for the simulation. FIG. 17A shows an input format to the input symbol conversion circuit 506, and TMCC is a signal before S / P conversion.
FIG. 17B shows an input format to the path memory 20021. TMCC is a signal after S / P conversion. The path memory length is 64, and the main signal after TMCC is TC-8PSK.
(R = 2/3) Only 64 symbols were used. Immediately before the first symbol of TMCC is inputted by the main signal of 64 symbols, the path memory 20021 stores the TC-8PSK.
(R = ２) It is in a state of being filled with 64 symbols.

FIG. 18 shows the BER of the decoded result simulated under the above conditions. C / N = -1 dB, and the rear TAB signal (w2 or w3) is stored in the path memory 20021.
When the last symbol is input, the BER for each symbol is calculated for the 64 symbols remaining in the path memory 20021. The horizontal axis is the path memory 200
21 shows 64 symbols remaining, and the vertical axis shows BER
Is shown. As is clear from this figure, the error rate of each symbol remaining in the path memory 20021 is improved in “with termination processing” in the present embodiment, compared with “without termination processing” in the conventional example. It turns out that there is.

(Embodiment 6) An error correction circuit according to Embodiment 6 of the present invention will be described with reference to the drawings. FIG. 19 shows an error correction circuit 60 according to the present embodiment.
1 is a block diagram showing a configuration of FIG. In the error correction circuit 601 shown in FIG. 19, blocks shown by thick solid lines are different from the conventional example. That is, the error correction circuit 20 shown in FIG.
The Viterbi decoder 1 controlled by the fixed branch signal and the fixed state signal instead of the Viterbi decoder 200002 of 001
02 is provided, and a Viterbi decoder control circuit 603 for generating a fixed branch signal and a fixed state signal is newly added. The other blocks, that is, the high / low hierarchy selection signal generation circuit 20003 to the channel selection circuit 20011, are the same as those shown in FIG.

The error correction circuit 60 constructed as described above
1 will be described. However, the Viterbi decoder 60
The operation after the output of No. 2 is the same as that of the conventional example, and the description is omitted.

FIG. 20 is a block diagram showing the configuration of the Viterbi decoder 602, and also shows the Viterbi decoder control circuit 603. The Viterbi decoder 602 has a depunctured S / P circuit 2006 and a Viterbi decoding circuit 604 indicated by a dotted line. Viterbi decoding circuit 60
4 is a branch metric calculation circuit 20018 and AC
S circuit 605, path metric memory 2008,
Path memory 20021. The Viterbi decoder 602 of the present embodiment is different from the Viterbi decoder 202 of the second embodiment shown in FIG. 6 only in the internal configuration of the ACS circuit 605.

With respect to the problem to be solved by the invention described with reference to FIG. 118, the Viterbi decoding control method according to the present embodiment at the time of transmission mode switching, and in particular, a control method utilizing the property of a fixed symbol sequence of a TAB signal explain. In error correction circuit 601 according to the present embodiment, as in the first embodiment, transmission control information decoding circuit 20010
Are output to the Viterbi decoder control circuit 603. The Viterbi decoder control circuit 603 uses the transmission mode / slot information to determine the fixed sequence symbol TA
Recognize the B signals (w1, w2, w3). As shown in FIG. 7A, from the time when the first symbol of the last 10 symbols of each TAB signal is input to the path memory 20021,
The tenth symbol of each TAB signal is stored in the path memory 20021.
Until it is input to the
Output to the circuit 605.

As shown in FIGS. 7A to 7C, the ACS circuit 605 transmits the path metric memory 20080 and the path metric The memory 22021 is controlled. Also, the Viterbi decoder control circuit 603 determines the first six symbols of each TAB signal, that is, the convolution circuit 10.
The signal until 014 is set to 1 state is stored in the path memory 20.
A fixed branch signal is generated and output to the ACS circuit 605 for the section input to the O.21.

As shown in FIG. 10B, the ACS circuit 605 uses the fixed branch signal output from the Viterbi decoder control circuit 603 to determine the first six symbols of each TAB signal in the same manner as in the third embodiment. The path metric memory 20082 and the path memory 20021 are controlled.
The Viterbi decoder 602 operates in the same manner as the Viterbi decoder 2 shown in the conventional example except when the transmission mode is switched as described above, that is, except for the control of TMCC (BPSK: r = 1/2) → transmission mode B.
The same operation as in 0002 is performed to output Viterbi decoded data.

With the configuration described above, similarly to the second embodiment, the TMCC (BPSK: r =
Viterbi decoding control using the property of the fixed symbol sequence of the (1/2) TAB signal (w1, w2 or w3) is performed. Therefore, the error correction circuit 601 according to the present embodiment completely blocks the influence of the transmission mode B after the mode switching, and sets the TMCC (BPSK: r = 1/2) Viterbi decoded data can be output. And TMCC (B
The influence of the transmission mode before the mode switching (PSK: r = 切 替) can be completely cut off.

Further, in the present embodiment, each TAB
Viterbi decoding control based on the fixed branch signal is performed for the first six symbols of the signal. Therefore, for all 16 symbols of the TAB signal, the Viterbi decoding control at the time of transmission mode switching is performed using the property of the fixed sequence,
As compared with the second embodiment, TMCC (BPSK: r = 1
/ 2) the error rate of the actual symbol data can be further reduced.

(Embodiment 7) An error correction circuit according to Embodiment 7 of the present invention will be described with reference to the drawings. FIG. 21 shows an error correction circuit 70 according to the present embodiment.
1 is a block diagram showing a configuration of FIG. In the error correction circuit 701 shown in FIG. 21, the block shown by a thick solid line is different from the conventional example, and the Viterbi decoder 702 controlled by a fixed branch signal is used instead of the Viterbi decoder 200002 of the error correction circuit 20001 of FIG. Are provided, and a Viterbi decoder control circuit 703 for generating a fixed branch signal and a symbol coordinate conversion signal, and an input symbol conversion circuit 506 controlled by a symbol coordinate conversion signal are newly added. The other blocks, that is, the high / low hierarchy selection signal generation circuit 20003 to the channel selection circuit 20011, are the same as those shown in FIG.

The error correction circuit 70 configured as described above
Each block 1 and its operation will be described. However,
The operation after the output of the Viterbi decoder 702 is as described in the conventional example, and the description is omitted.

FIG. 22 is a block diagram showing the configuration of the Viterbi decoder 702, and shows the Viterbi decoder control circuit 703 and the input symbol conversion circuit 506 together. The Viterbi decoder 702 is connected to the de-punctured S / P circuit 20.
016 and a Viterbi decoding circuit 704 indicated by a dotted line. The Viterbi decoding circuit 704 includes a branch metric calculation circuit 20018, an ACS circuit 705, a path metric memory 20080, and a path memory 20021.
And Viterbi decoder 702 of the present embodiment
Is the Viterbi decoder 2000 according to the fifth embodiment shown in FIG.
2, only the internal configuration of the ACS circuit 705 is different.

With respect to the problem to be solved by the invention described with reference to FIG. 118, a Viterbi decoding control method according to the present embodiment at the time of transmission mode switching, particularly a control method utilizing the property of a fixed symbol sequence of a TAB signal explain. In error correction circuit 701 of the present embodiment, as in the first embodiment, transmission control information decoding circuit 20010
Are output to the Viterbi decoder control circuit 703. The Viterbi decoder control circuit 703 recognizes a TAB signal (w1, w2, w3) that is a fixed sequence symbol based on the transmission mode / slot information. As shown in FIG. 87 or FIG.
After 32 symbols (w2 = xxx0B677h or w3 = xxxF4988h) of the TAB signal after (BPSK: r = 信号),
In a section where the last 20 symbols in which the state of the convolution circuit 10014 is determined are input to the input symbol conversion circuit 506, a symbol coordinate conversion signal is generated and output to the input symbol conversion circuit 506.

Input symbol conversion circuit 506 performs the same operation as in the fifth embodiment, and outputs I / Q data to Viterbi decoder 702. The Viterbi decoder control circuit 70
3 is the path memory 2 until the first six symbols of each TAB signal, that is, until the state of the convolution circuit 10014 is determined to be one.
A fixed branch signal is generated for the section input to 0021 and output to the ACS circuit 705. And ACS
The circuit 705 controls the path metric memory 20080 and the path memory 20021 by using the fixed branch signal output from the Viterbi decoder control circuit 703 for the first six symbols of each TAB signal in the same manner as in the third embodiment. . Further, the Viterbi decoder 702 performs the above-described transmission mode switching, that is, TMCC (BPSK: r = 1 /
2) Except for the control of the transmission mode B, the same operation as that of the Viterbi decoder 20002 shown in the conventional example is performed to output Viterbi decoded data.

According to the above-described configuration, TMCC (BPSK: r =
Viterbi decoding control using the property of the fixed symbol sequence of the (1/2) TAB signal (w1, w2 or w3) is performed. Therefore, the error correction circuit 701 according to the present embodiment blocks the influence of the transmission mode B after the mode switching, and the TMCC (BPSK: r = 1) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching. / 2) Viterbi decoded data can be output. And TMCC (BPS
K: r = １ ／), the influence of the transmission mode before the mode switching can also be cut off.

Furthermore, in the present embodiment, each TAB
Viterbi decoding control based on the fixed branch signal is performed for the first six symbols of the signal. Therefore, for all 16 symbols of the TAB signal, the Viterbi decoding control at the time of transmission mode switching is performed using the property of the fixed sequence, and the TMCC (BPSK: r = 1 /
The error rate of the actual symbol data 2) can be further reduced.

(Eighth Embodiment) An error correction circuit according to an eighth embodiment of the present invention will be described with reference to the drawings. FIG. 23 shows an error correction circuit 80 according to the present embodiment.
1 is a block diagram showing a configuration of FIG. In the error correction circuit 801 shown in FIG. 23, blocks shown by thick solid lines are different from the conventional example, and are controlled by a state reduction signal and a definite state signal instead of the Viterbi decoder 200002 of the error correction circuit 20001 of FIG. A Viterbi decoder 802 is provided,
The feature is that a Viterbi decoder control circuit 803 for generating a state reduction signal and a confirmed state signal is newly added. Other blocks, that is, high / low hierarchy selection signal generation circuit 2
It is the same as that shown in FIG. 98 that the channel selection circuit 20011 is provided.

The error correction circuit 80 configured as described above
Each block 1 and its operation will be described. However,
The operation after the output of the Viterbi decoder 802 is the same as that of the conventional example, and the description is omitted.

FIG. 24 is a block diagram showing the configuration of the Viterbi decoder 802, and also shows a Viterbi decoder control circuit 803. The Viterbi decoder 802 has a depunctured S / P circuit 20066 and a Viterbi decoding circuit 804 indicated by a dotted line. Viterbi decoding circuit 8
04 is a branch metric calculation circuit 20018 and A
CS circuit 805 and path metric memory 20020
And a path memory 20021. The Viterbi decoder 802 of the present embodiment is different from the Viterbi decoder 202 of the second embodiment shown in FIG.
Only the internal configuration of No. 5 has changed.

With respect to the problem to be solved by the invention described with reference to FIG. 118, the Viterbi decoding control method according to the present embodiment at the time of transmission mode switching, and in particular, a control method utilizing the property of a fixed symbol sequence of a TAB signal explain. In error correction circuit 801 according to the present embodiment, as in the first embodiment, transmission control information decoding circuit 20010
Are output to the Viterbi decoder control circuit 803.

In the same manner as in the second embodiment, Viterbi decoder control circuit 803 uses the transmission mode / slot information output from transmission control information decoding circuit 20010 to generate TAB signals (w1, w2, w3 ) Recognize. As shown in FIG. 7A, the first symbol of the last 10 symbols of each TAB signal is stored in the path memory 2002.
From the point in time when the signal is input to 1, the point in time when the tenth symbol of each TAB signal is input to the path memory 20021, a determined state signal is generated and output to the ACS circuit 805.

The ACS circuit 805 is shown in FIGS.
As shown in FIG. 23, the path metric memory 20080 and the path memory 20021 are determined in the same manner as in the second embodiment by the definite state signal output from the Viterbi decoder control circuit 803.
Control. Also, the Viterbi decoder control circuit 803
The first six symbols of each TAB signal, ie, convolution circuit 1
Until 0014 is determined to be in one state, the path memory 200
For the section input to 21, a state reduction signal is generated and output to the ACS circuit 805.

The ACS circuit 805 uses the state reduction signal output from the Viterbi decoder control circuit 803 to generate each TAB.
For the first six symbols of the signal, the path metric memory 20082 and the path memory 20021 are controlled in the same manner as in the fourth embodiment, and the number of states until the convolution circuit 10014 is determined to be in one state as shown in FIG. In half. Also, the Viterbi decoder 802 performs the above-described transmission mode switching, that is, TMCC (BPSK:
r = 1/2) → Except for the control of the transmission mode B, the same operation as that of the conventional Viterbi decoder 20002 is performed to output Viterbi decoded data.

According to the above-described configuration, TMCC (BPSK: r =
Viterbi decoding control using the property of the fixed symbol sequence of the (1/2) TAB signal (w1, w2 or w3) is performed. Therefore, the error correction circuit 801 of the present embodiment completely shuts off the influence of the transmission mode B after the mode switching, and sets the TMCC (BPSK: r = 1/2) Viterbi decoded data can be output. And TMCC (B
(PSK: r = 1/2) completely eliminates the influence of the transmission mode before the mode switching.

Further, in the present embodiment, each TAB
Viterbi decoding control is performed on the first six symbols of the signal using the state reduction signal. Therefore, for all 16 symbols of the TAB signal, the Viterbi decoding control at the time of transmission mode switching is performed using the property of the fixed sequence, and the TMCC (BPSK: r = 1 /
The error rate of the actual symbol data 2) can be further reduced.

(Embodiment 9) An error correction circuit according to Embodiment 9 of the present invention will be described with reference to the drawings. FIG. 25 shows an error correction circuit 90 according to the present embodiment.
1 is a block diagram showing a configuration of FIG. In the error correction circuit 901 shown in FIG. 25, blocks shown by thick solid lines are different from the conventional example, and are controlled by a state reduction signal and a fixed branch signal instead of the Viterbi decoder 200002 of the error correction circuit 20001 of FIG. A feature is that a Viterbi decoder 902 is provided, and a Viterbi decoder control circuit 903 for generating a state reduction signal and a fixed branch signal is newly added. The other blocks, that is, the high / low hierarchy selection signal generation circuit 20003 to the channel selection circuit 20011, are the same as those shown in FIG.

The error correction circuit 90 configured as described above
Each block 1 and its operation will be described. However,
The operation after the output of the Viterbi decoder 902 is as described in the conventional example, and the description is omitted.

FIG. 26 is a block diagram showing the configuration of the Viterbi decoder 902, and also shows a Viterbi decoder control circuit 903. The Viterbi decoder 902 has a depunctured S / P circuit 20066 and a Viterbi decoding circuit 904 indicated by a dotted line. Viterbi decoding circuit 9
04 is a branch metric calculation circuit 20018 and A
CS circuit 905 and path metric memory 20020
And a path memory 20021. The Viterbi decoder 902 of the present embodiment is different from the Viterbi decoder 302 of the third embodiment shown in FIG.
Only the internal configuration of No. 5 has changed.

With respect to the problem to be solved by the invention described with reference to FIG. 118, the Viterbi decoding control method according to the present embodiment at the time of transmission mode switching, in particular, a control method utilizing the property of a fixed symbol sequence of a TAB signal explain. In error correction circuit 901 according to the present embodiment, as in the first embodiment, transmission control information decoding circuit 20010
Are output to the Viterbi decoder control circuit 903. As in the third embodiment, the Viterbi decoder control circuit 903 uses the transmission mode / slot information to determine the fixed sequence symbol TA
Recognize the B signals (w1, w2, w3). A fixed branch signal is generated and output to the ACS circuit 905 from the time when the first symbol of the 16 symbols of each TAB signal is input to the path memory 20021 to the time when the 16th symbol of each TAB signal is input to the path memory 20021. I do.

As shown in FIG. 10, the ACS circuit 905 controls the path metric memory 20020 and the path memory 22021 by the fixed branch signal output from the Viterbi decoder control circuit 903 in the same manner as in the third embodiment. Do. In addition, the Viterbi decoder control circuit 903 controls each T
The first six symbols of the AB signal, that is, the convolution circuit 100
For a section that is input to the path memory 20021 until the state of 14 is determined to be 1 state, a state reduction signal is generated and AC
Output to S circuit 905.

As shown in FIG. 13, the ACS circuit 905 uses the state reduction signal output from the Viterbi decoder control circuit 903 to pass the first six symbols of each TAB signal in the same manner as in the fourth embodiment. The metric memory 20082 and the path memory 20021 are controlled, and the number of states is reduced by half until the convolution circuit 10014 is determined to be one state. Also, the Viterbi decoder 902
When the transmission mode is switched as described above, that is, when the TMCC (BPS
K: r = 1/2) → Except for the control of the transmission mode B, the same operation as that of the conventional Viterbi decoder 20002 is performed to output Viterbi decoded data.

With the configuration described above, TMCC (BPSK: r =
Viterbi decoding control using all the fixed symbol sequences of the (1/2) TAB signal (w1, w2 or w3) is performed. Therefore, the error correction circuit 901 of the present embodiment blocks the influence of the transmission mode B after the mode switching, and the TMCC (BPSK: r = 1) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching. / 2) Viterbi decoded data can be output. And TMCC (BPSK:
(r = 1/2) completely eliminates the influence of the transmission mode before the mode switching.

Further, in the present embodiment, each TAB
Viterbi decoding control is performed on the first six symbols of the signal using the state reduction signal. Therefore, for all 16 symbols of the TAB signal, the Viterbi decoding control at the time of transmission mode switching can be performed by using the property of the fixed sequence twice, such as the fixed branch and the state reduction. Therefore, as compared with the third embodiment, TMCC (BPSK: r = 1/2)
Can be further reduced.

(Embodiment 10) Embodiment 1 of the present invention
The error correction circuit at 0 will be described with reference to the drawings. FIG. 27 is a block diagram showing a configuration of the error correction circuit 1001 in the present embodiment. In the error correction circuit 1001 shown in FIG. 27, blocks shown by thick solid lines are different from the conventional example, and the error correction circuit 2000 shown in FIG.
1, a Viterbi decoder 1002 controlled by a state reduction signal is provided, and a Viterbi decoder control circuit 1003 for generating a state reduction signal and a symbol coordinate conversion signal is controlled by a symbol coordinate conversion signal. The feature is that an input symbol conversion circuit 506 is newly added. The other blocks, that is, the high / low hierarchy selection signal generation circuit 20003 to the channel selection circuit 20011, are the same as those shown in FIG.

The error correction circuit 10 configured as described above
01 and its operation will be described. However, the operation after the output of the Viterbi decoder 1002 is as described in the conventional example, and the description is omitted.

FIG. 28 is a block diagram showing the configuration of the Viterbi decoder 1002, and also shows a Viterbi decoder control circuit 1003 and an input symbol conversion circuit 506.
The Viterbi decoder 1002 includes a depunctured S / P circuit 2006 and a Viterbi decoding circuit 100 shown by a dotted line.
And 4. The Viterbi decoding circuit 1004 includes a branch metric calculation circuit 20008 and an ACS circuit 10
05, a path metric memory 20080, and a path memory 20021. The Viterbi decoder 1002 of the present embodiment is different from the Viterbi decoder 2 of the fifth embodiment.
Only the internal configuration of the ACS circuit 1005 is different from that of 0002.

With respect to the problem to be solved by the invention described with reference to FIG. 118, the Viterbi decoding control method according to the present embodiment at the time of transmission mode switching, and in particular, a control method utilizing the property of a fixed symbol sequence of a TAB signal explain. In error correction circuit 1001 of the present embodiment,
As in the first embodiment, the transmission control information decoding circuit 2001
0, the transmission mode / slot information decoded is output to the Viterbi decoder control circuit 1003.

The Viterbi decoder control circuit 1003 is similar to the fifth embodiment in that the transmission control information decoding circuit
TAB signals (w1, w2, w3), which are fixed sequence symbols, according to the transmission mode / slot information output from
Recognize. As shown in FIG. 87 or FIG.
After C (BPSK: r = １ ／), of the 32 symbols (w2 = xxx0B677h or w3 = xxxF4988h) of the 32 symbols of the TAB signal, the rear 2 in which the state of the convolution circuit 10014 is determined
For a section where 0 symbol is input to the input symbol conversion circuit 506, a symbol coordinate conversion signal is generated and output to the input symbol conversion circuit 506. The input symbol conversion circuit 506 performs the same operation as in the fifth embodiment,
The I / Q data is output to the Viterbi decoder 1002.

Further, the Viterbi decoder control circuit 1003
The first six symbols of each TAB signal, ie, convolution circuit 1
Until 0014 is determined to be in one state, the path memory 2002
A state reduction signal is generated for the section input to 1 and output to the ACS circuit 1005. ACS circuit 1005
Controls the path metric memory 20080 and the path memory 20021 for the first six symbols of each TAB signal in the same manner as in the fourth embodiment, based on the state reduction signal output from the Viterbi decoder control circuit 1003. As shown in FIG. 13, the number of states is reduced by half until the convolution circuit 10014 is determined to be in one state. The Viterbi decoder 1002 performs the same operation as the conventional Viterbi decoder 20002 except for the above-described transmission mode switching, that is, control of TMCC (BPSK: r = 1/2) → transmission mode B. And outputs Viterbi decoded data.

With the configuration described above, TMCC (BPSK: r =
Viterbi decoding control using a fixed symbol sequence of a 1/2) TAB signal (w1, w2 or w3) is performed. Therefore,
The error correction circuit 1001 of the present embodiment completely shuts off the influence of the transmission mode B after the mode switching, and sets the TMCC (BPSK: r = 1) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching. / 2) Viterbi decoded data can be output. And TMCC (BPS
K: r = 1/2) completely eliminates the influence of the transmission mode before the mode switching.

Further, in the present embodiment, each TAB
Viterbi decoding control is performed on the first six symbols of the signal using the state reduction signal. Therefore, for all 16 symbols of the TAB signal, the Viterbi decoding control at the time of transmission mode switching is performed using the property of the fixed sequence. Therefore, as compared with the fifth embodiment, TMCC (BPSK: r = 1
/ 2) the error rate of the actual symbol data can be further reduced.

(Embodiment 11) Embodiment 1 of the present invention
1 will be described with reference to the drawings. FIG. 29 is a block diagram showing a configuration of the error correction circuit 1101 according to the present embodiment. In the error correction circuit 1101 shown in FIG. 29, the blocks shown by thick solid lines are different from the conventional example, and the error correction circuit 2000 shown in FIG.
1 instead of the one Viterbi decoder 20002,
A Viterbi decoder 1102 controlled by a fixed branch signal and a fixed state signal is provided, and a Viterbi decoder control circuit 1103 for generating a state reduction signal, a fixed branch signal, and a fixed state signal is newly added. is there. Other blocks, that is, high / low hierarchy selection signal generation circuit 2
It is the same as that shown in FIG. 98 that the channel selection circuit 20011 is provided.

The error correction circuit 11 configured as described above
01 and its operation will be described. However, the operation after the output of the Viterbi decoder 1102 is as described in the conventional example, and the description is omitted.

FIG. 30 is a block diagram showing the configuration of the Viterbi decoder 1102, and also shows a Viterbi decoder control circuit 1103. As shown in FIG. 30, the Viterbi decoder 1102 includes a de-punctured S / P circuit 2001.
6 and a Viterbi decoding circuit 1104 indicated by a dotted line. The Viterbi decoding circuit 1104 includes a branch metric calculation circuit 20018, an ACS circuit 1105, a path metric memory 2008, and a path memory 2002.
And 1. That is, the Viterbi decoder 1102 of the present embodiment is different from the Viterbi decoder 202 of the second embodiment only in the internal configuration of the ACS circuit 1105.

With respect to the problem to be solved by the invention described with reference to FIG. 118, the Viterbi decoding control method according to the present embodiment at the time of transmission mode switching, and in particular, a control method utilizing the property of a fixed symbol sequence of a TAB signal explain.

In the error correction circuit 1101 of the present embodiment, the transmission mode / slot information of FIG. 82 decoded by the transmission control information decoding circuit 20010 is output to the Viterbi decoder control circuit 1103 as in the first embodiment. Is done. The Viterbi decoder control circuit 1103 recognizes the TAB signals (w1, w2, w3), which are fixed sequence symbols, based on the transmission mode / slot information, as in the second embodiment. As shown in FIG.
From the point in time when the first symbol of the zero symbol is input to the path memory 20021, the tenth symbol (S
A final state signal is generated until the / P conversion final symbol) is input to the path memory 20021 and A in FIG.
Output to the CS circuit 1105.

[0297] The ACS circuit 1105 has the configuration shown in FIG.
As shown in (c), the path metric memory 2008 and the path memory 2 in the same manner as in the second embodiment, based on the definite state signal output from the Viterbi decoder control circuit 1103.
0021 is controlled. Viterbi decoder control circuit 1
An ACS circuit 1105 generates a fixed branch signal and a state reduction signal for a leading six symbols of each TAB signal, that is, a section input to the path memory 20021 until the convolution circuit 10014 is determined to be in one state.
Output to

The ACS circuit 1105 uses the fixed branch signal output from the Viterbi decoder control circuit 1103 as shown in FIG. 10 (b) to determine the first six symbols of each TAB signal in the same manner as in the third embodiment. The path metric memory 20082 and the path memory 20021 are controlled. Further, the ACS circuit 1105 uses the state reduction signal output from the Viterbi decoder control circuit 1103 to output each TA.
For the first six symbols of the B signal, the path metric memory 20082 and the path memory 20021 are controlled in the same manner as in the fourth embodiment, and the number of states until the convolution circuit 10014 is fixed to one state as shown in FIG. In half. Also, the Viterbi decoder 1102 performs the above-described transmission mode switching, that is, the TMCC (BPS
K: r = 1/2) → Except for the control of the transmission mode B, the same operation as that of the conventional Viterbi decoder 20002 is performed to output Viterbi decoded data.

According to the above-described configuration, TMCC (BPSK: r =
Viterbi decoding control using the property of the fixed symbol sequence of the (1/2) TAB signal (w1, w2 or w3) is performed. Therefore, the error correction circuit 1101 of the present embodiment completely shuts off the influence of the transmission mode B after the mode switching, and sets the TMCC (BPSK: r) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching. = 1/2) Viterbi decoded data can be output. And TMCC
The influence of the transmission mode before the mode switching of (BPSK: r = 1/2) can be completely cut off.

Furthermore, in the present embodiment, each TAB
Viterbi decoding control is performed for the first six symbols of the signal using the fixed branch signal and the state reduction signal. Therefore, TA
This means that the Viterbi decoding control at the time of transmission mode switching is performed for all 16 symbols of the B signal by using the property of the fixed sequence, and the TMC is compared with the second and sixth embodiments.
The error rate of the actual symbol data of C (BPSK: r = １ ／) can be further reduced.

(Embodiment 12) Embodiment 1 of the present invention
2 will be described with reference to the drawings. FIG. 31 is a block diagram showing a configuration of the error correction circuit 1201 according to the present embodiment. In the error correction circuit 1201 shown in FIG. 31, blocks shown by thick solid lines are different from the conventional example, and the error correction circuit 2000 shown in FIG.
Viterbi decoder 1202 controlled by a state reduction signal and a fixed branch signal instead of one Viterbi decoder 20002
And a Viterbi decoder control circuit 1 for generating a state reduction signal, a fixed branch signal, and a symbol coordinate conversion signal
It is characterized by adding a new symbol 203 and an input symbol conversion circuit 506 controlled by a symbol coordinate conversion signal. The other blocks, that is, the high / low hierarchy selection signal generation circuit 20003 to the channel selection circuit 20011, are the same as those shown in FIG.

The error correction circuit 12 configured as described above
01 and its operation will be described. However, the operation after the output of the Viterbi decoder 1202 is as described in the conventional example, and the description is omitted.

FIG. 32 is a block diagram showing a configuration of the Viterbi decoder 1202, and also shows a Viterbi decoder control circuit 1203 and an input symbol conversion circuit 506. The Viterbi decoder 1202 includes a depunctured S / P circuit 2006 and a Viterbi decoder 1204 indicated by a dotted line.
And The Viterbi decoding circuit 1204 includes a branch metric calculation circuit 20018 and an ACS circuit 120
5, a path metric memory 20080, and a path memory 20021. That is, the Viterbi decoder 1202 of the present embodiment is different from the Viterbi decoder 20 of the fifth embodiment.
Only the internal configuration of the ACS circuit 1205 is different from that of 002.

Regarding the problem to be solved by the invention described with reference to FIG. 118, the Viterbi decoding control method according to the present embodiment at the time of transmission mode switching, and in particular, a control method utilizing the property of a fixed symbol sequence of a TAB signal explain.

In the error correction circuit 1201 of the present embodiment, the transmission mode / slot information of FIG. 82 decoded by the transmission control information decoding circuit 20010 is transmitted to the Viterbi decoder control circuit 1203 as in the first embodiment. Is output. The Viterbi decoder control circuit 1203 recognizes the TAB signals (w1, w2, w3), which are fixed sequence symbols, based on the transmission mode / slot information, as in the fifth embodiment. As shown in FIG. 87 or FIG.
After 32 symbols (w2 = xxx0B677h or w3 = xxxF4988h) of the TAB signal after (BPSK: r = 信号),
In a section where the last 20 symbols in which the state of the convolution circuit 10014 is determined are input to the input symbol conversion circuit 506, a symbol coordinate conversion signal is generated and output to the input symbol conversion circuit 506.

The input symbol conversion circuit 506 performs the same operation as in the fifth embodiment as shown in FIG.
The data is output to the Viterbi decoder 1202. Further, the Viterbi decoder control circuit 1203 converts the fixed branch signal and the state reduction signal for the first six symbols of each TAB signal, that is, for the section input to the path memory 22021 until the state of the convolution circuit 10014 is determined to one state. Generate A
Output to the CS circuit 1205. The ACS circuit 1205 is
As shown in FIG. 10B, the Viterbi decoder control circuit 12
03 by the fixed branch signal output from the
For the first six symbols of the signal, the path metric memory 20080 and the path memory 20021 are controlled as in the third embodiment. Further, the ACS circuit 1205
Is, as shown in FIG. 13, a Viterbi decoder control circuit 120.
In the same way as in the fourth embodiment, the path metric memory 20020 and the path memory 20
021 is performed, and the number of states is reduced by half until the convolution circuit 10014 is determined to be one state.

The Viterbi decoder 1202 performs the above-described transmission mode switching, that is, TMCC (BPSK: r =
1/2) → Except for the control of the transmission mode B, the same operation as that of the conventional Viterbi decoder 20002 is performed to output Viterbi decoded data.

According to the configuration described above, similarly to the fifth embodiment, the TMCC (BPSK: r =
Viterbi decoding control using the property of the fixed symbol sequence of the (1/2) TAB signal (w1, w2 or w3) is performed. Therefore, the error correction circuit 1201 of the present embodiment blocks the influence of the transmission mode B after the mode switching and removes the TMCC (BPSK: r = 1) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching. / 2) Viterbi decoded data can be output. And TMCC (BPS
K: r = １ ／), the influence of the transmission mode before the mode switching can also be cut off.

Furthermore, in the present embodiment, each TAB
Viterbi decoding control is performed for the first six symbols of the signal using the fixed branch signal and the state reduction signal. Therefore, TA
Viterbi decoding control at the time of transmission mode switching is performed for all 16 symbols of the B signal by using the property of the fixed sequence.
The error rate of the actual symbol data of CC (BPSK: r = １ ／) can be further reduced.

(Embodiment 13) Embodiment 1 of the present invention
3 will be described with reference to the drawings. FIG. 33 is a block diagram showing a configuration of the error correction circuit 1301 in the present embodiment. In the error correction circuit 1301 shown in FIG. 33, blocks shown by thick solid lines are different from the conventional example, and a de-interleave circuit 1302 and a tuning circuit 1303 having different internal configurations are provided. It is characterized by being configured to be controlled by the slot selection signal output by 1303. Other blocks, that is, a Viterbi decoder 20002 to a symbol / byte conversion circuit 20004;
MPEG synchronization byte / dummy slot insertion circuit 200
06 to the transmission control information decoding circuit 20010 are the same as those shown in FIG.

The error correction circuit 13 configured as described above
01 and its operation will be described. However, the operation before the input to the de-interleave circuit 1302 and the operation after the output are the same as those in the conventional example, and the description is omitted.

FIG. 34 shows a de-interleave circuit 1302
FIG. 3 is a block diagram illustrating a configuration example of FIG. The de-interleave circuit 1302 includes a write address generation circuit 1304
And a read address generation circuit 1305 and a memory circuit 1306. Note that, in order to perform de-interleaving, the memory circuit 1306 of this embodiment needs 24
A memory area of 2 banks of 8 slots is used.

As described in the problem to be solved by the invention, the conventional de-interleaving circuit 20005 performs de-interleaving using an unnecessary memory area. The de-interleave circuit of the present embodiment is configured to solve this problem. Hereinafter, the operation of the present embodiment will be described.

As shown in the conventional example, the data sequence input to the de-interleave circuit 1302 is as follows: TS1: <high-layer image> TC-8PSK: 22 slots <low-layer signal Image> QPSK (r = １ ／): 2 slots (including one dummy slot) TS2: <high-layer image> TC-8PSK: 20 slots <low-layer image> BPSK (r = １ ／): 4 It is assumed that two types of TS (of three dummy slots) are input as shown in FIG.

In the conventional example, as shown in FIG. 109, the entire input data sequence of 48 slots per one frame is written to and read from the memory circuit 20028 of FIG. Therefore, the output data sequence from the de-interleave circuit 20005 is shown in FIG.
(A).

On the other hand, in the de-interleave circuit 1302 of the present embodiment, 1TS selected by the slot selection signal output from the channel selection circuit 1303, in this case, a data sequence of only 24 slots / frame Is written to the memory circuit 1306 and readout is performed. Therefore, the write address generation circuit 1 shown in FIG.
The read address generation circuit 304 and the read address generation circuit 1305 generate only an address corresponding to the selected one TS slot, and output the generated address to the memory circuit 1306. The address of the slot corresponding to the TS that is not selected is free-run. Therefore, the de-interleave circuit 130
The output data series from 2 is as shown in FIG.

With the above structure, the interleave circuit 1302 of the present embodiment reduces the memory area to be used by half by writing and reading the input data sequence of only one TS to be tuned to the memory circuit 1306. be able to.

In the present embodiment, TS1, TS2
Both occupy 24 slots per frame. For example, if the maximum number of slots per frame occupied by 1TS is determined in the BS digital broadcasting standard, the maximum number of slots × 8 slots It is sufficient that two banks of memory areas are prepared, and the memory area used by the memory circuit 1306 is not limited to two banks of 24 × 8 slots as in this embodiment.

In the above embodiment, the data sequence input to the de-interleave circuit 1302 is such that one type of TS is selected from two types of TS per frame (48 slots). Here, for example, TS1: <high-layer image> TC-8PSK: 14 slots <low-layer image> QPSK (r = 1/2): 2 slots (of which, one dummy slot) TS2: <high-layer image> TC-8PSK: 12 slots <Low-layer image> QPSK (r = 3/4): 4 slots (including one dummy slot) TS3: <High-layer image> TC-8PSK: 12 slots <Low-layer image> BPSK (r = 1/2): Consider a case where three types of TSs of 4 slots (including 3 dummy slots) are input. That is, 3TS is assigned to one transponder. When one type of TS is selected, as described above, only the selected one TS needs to be written to the memory circuit 1306 and read. When two types of TSs are selected, for example, when one TS is displayed on a monitor and another one is video-recorded, only the selected two TSs are stored in the memory circuit 130.
6 may be written and read. In this case,
In the BS digital broadcasting standard, 1 occupied by 1 TS
If the maximum number of slots per frame is determined,
It is sufficient to prepare a memory area for two banks of the maximum number of slots × 8 × 2 slots. In addition, for example, 8 types of TS
Is input, and the same applies to a case where four types of TS are selected.

(Embodiment 14) Embodiment 1 of the present invention
4 will be described with reference to the drawings. FIG. 36 is a block diagram showing a configuration of the error correction circuit 1401 in the present embodiment. The error correction circuit 1401 shown in FIG. 36 differs from the conventional example in a block shown by a thick solid line, and includes a de-interleave circuit 1402, a de-randomize circuit 1407, and a tuning circuit 1403 having different internal configurations. Circuit 1402 and de-randomizing circuit 1407
It is characterized in that it is controlled by the slot selection signal output from 403 and that the speed conversion circuit 200009 is eliminated. Other blocks, that is, Viterbi decoder 20002 to symbol / byte conversion circuit 2000
4. MPEG synchronization byte / dummy slot insertion circuit 2
The functions of the RS decoding circuit 200008 and the transmission control information decoding circuit 20090 are the same as those shown in FIG.

The error correction circuit 14 configured as described above
01 and its operation will be described. However, the operation before the input of the de-interleave circuit 1402 and the operation after the output of the de-randomize circuit 1407 are as shown in the conventional example, and the description is omitted.

FIG. 37 shows a de-interleave circuit 1402
FIG. 3 is a block diagram illustrating a configuration example of FIG. The de-interleave circuit 1402 includes a write address generation circuit 1404
And a read address generation circuit 1405 and a memory circuit 1406. Note that, in order to perform de-interleaving, the memory circuit 1406 of the present embodiment needs 24
It is assumed that a memory area of 2 banks of 8 slots is used.

As described in the problem to be solved by the invention, the conventional error correction circuit 20001 has an unnecessary speed conversion circuit. The de-interleave circuit and the de-randomize circuit 1407 of the present embodiment are configured to solve this problem.

As shown in the conventional example, the data sequence input to de-interleave circuit 1402 is as shown in FIG.
As shown in (b), per frame (48 slots), TS1: <high-layer image> TC-8PSK: 22 slots <low-layer image> QPSK (r = １ ／): 2 slots TS2: <high-layer image> TC-8PSK: 20 slots <low-layer image> BPSK (r = 1/2): 4 slots (of which, dummy 3 slots) are input. Shall be.

In the conventional example, the output data series from the de-interleave circuit 20005 is as shown in FIG. In the above-described thirteenth embodiment, as the output data sequence from de-interleave circuit 1302, slots corresponding to the selected TS are output in a burst manner as shown in FIG. 35 (b).

In this embodiment, the thirteenth embodiment
Similarly to the above, 1TS selected by the slot selection signal output from the channel selection circuit 1403, in this case, a data sequence of only 24 slots / frame is stored in the memory circuit 14
Control is performed so as to write to the address 06. Therefore, the write address generation circuit 1404 generates only an address corresponding to the selected slot of 1 TS and outputs the generated address to the memory circuit 1406. The address of the slot corresponding to the TS that is not selected is free-run.

Also, the data sequence of only 1 TS selected by the slot selection signal output from the tuning circuit 1403 is not transmitted from the memory circuit 1406 in a burst manner,
Control is performed so that reading is performed continuously. Therefore, the read address generation circuit 1405 outputs the selected 1TS
And generates only the address corresponding to the slot of the memory circuit 140 at half the writing speed (= 24/48).
6 is output. Note that the address of the slot corresponding to the TS that is not selected is not generated and is skipped. The output data sequence from the de-interleave circuit 1402 in this case is as shown in FIG.

With the above structure, the interleave circuit 1402 of the present embodiment reduces the memory area to be used by half by writing the input data sequence of only one TS to be tuned to the memory circuit 1406 and reading it out. be able to. The interleave circuit 1402 performs speed conversion and outputs the deinterleaved data sequence to the MPEG synchronization byte / dummy slot insertion circuit 20006.

In the above embodiment, TS1, TS1,
Each of the two occupies 24 slots per frame. For example, if the maximum number of slots per frame occupied by 1TS is determined in the BS digital broadcasting standard, the maximum number of slots × 8 slots It is sufficient to prepare two banks of memory areas, and the memory area used by the memory circuit 1406 is not limited to two banks of 24 × 8 slots as in the above embodiment.

In the above embodiment, the data sequence input to de-interleave circuit 1402 is composed of two types of TS per frame (48 slots), and one type of TS is selected. And Here, for example, TS1: <high-layer image> TC-8PSK: 14 slots <low-layer image> QPSK (r = 1/2): 2 slots (of which, one dummy slot) TS2: <high-layer image> TC-8PSK: 12 slots <Low-layer image> QPSK (r = 3/4): 4 slots (including one dummy slot) TS3: <High-layer image> TC-8PSK: 12 slots <Low-layer image> BPSK (r = 1/2): Consider a case where three types of TSs of 4 slots (including 3 dummy slots) are input. That is, one transponder is composed of 3TSs. When one type of TS is selected, as described above, only the selected one TS is written into the memory circuit 1406, and the speed is converted.
Reading may be performed at a speed of 16/48 = 1/3. When two types of TSs are selected, only one selected TS is written into the memory circuit 1406, as in the case where one TS is displayed on the monitor and one TS is video-recorded.
Reading may be performed at a speed of 2/48 = ２. In this case, if the maximum number of slots per frame occupied by one TS is determined in the BS digital broadcasting standard, two banks of memory areas of the maximum number of slots × 8 × 2 slots can be prepared. I just need. In addition, for example, 8
The same applies when four types of TS are selected and four types of TS are selected.

As described in the problem to be solved by the invention, when the above-described de-interleave circuit 1402 is used, the data sequence input to the conventional de-randomize circuit 20007 is not a continuous slot but a discrete one. Will be input. Therefore, when the conventional de-randomizing circuit 20007 is used, de-randomizing cannot be performed. The de-randomizing circuit according to the present embodiment is configured to solve this problem. The operation of this point will be described below.

FIG. 39 is a block diagram showing a structure of a de-randomizing circuit 1407 in the present embodiment. The de-randomizing circuit 1407 includes a PN generation circuit 1408 indicated by a broken line, a P / S conversion circuit 20030, and an S / P
Conversion circuit 20031 and gate signal generation circuit 20032
And an ex-or circuit 20033. The PN generation circuit 1408 includes an initial value generation circuit 1409 controlled by a slot selection signal. The de-randomizing circuit 1407 in this embodiment is different from the conventional de-randomizing circuit 20007 shown in FIG.
An initial value generation circuit 1409 is added.

As shown in FIG. 38B, the data sequence output from de-interleave circuit 1402 is
EG synchronous byte / dummy slot insertion circuit 20006
, An MPEG synchronization byte is inserted at the beginning of each slot. In addition, according to the dummy slot information output from the transmission control information decoding circuit 20010, an MPEG null packet is inserted in the dummy slot section, and a byte data sequence as shown in FIG. 40 is output to the de-randomizing circuit 1407. .

The de-randomizing circuit 1407 is shown in FIG.
Is de-randomized at a cycle of one superframe. PN generating circuit 1408, the characteristics are represented by the generator polynomial ^{(1 + x 14 + x 15} ), and is reset by the second byte of the first frame of each superframe. The initial value at this time is “100101010000000”. The input data converted into the bit series by the P / S conversion circuit 20030 and the output value of the PN generation circuit 1408 are represented by e
The multiplication is performed by an x-or circuit 20033. The result of this multiplication is converted into a byte data series in the S / P conversion circuit 20031 and output to the RS decoding circuit 20008 in FIG.

However, according to the gate signal generated by the gate signal generation circuit 20032, during the period of the first byte of each 204 bytes of the slot and the dummy slot, the PN generation circuit 1408 operates as a free-run during the ex-or circuit 20033.
Does not multiply the data. Also, in FIG.
1 (1) to TS1 (22), the PN generation circuit 140
8 operates continuously. However, for the TS1 (23), the initial value generation circuit 1409 loads the initial value corresponding to the TS1 (23) in the second byte of the slot by the slot selection signal. This is shown in FIG.
This is because TS1 (22) and TS1 (23) are not continuously randomized as shown in FIG. Therefore, the initial value generation circuit 1409 in FIG. 39 may be configured to generate the initial value of the second byte of all 48 × 8 slots by the slot selection signal.

With the above configuration, the de-randomizing circuit 1407 of the present embodiment can perform de-randomizing in response to the use of the above-described de-interleaving circuit 1402. It can be unnecessary. In this case, an enable signal as shown in FIG. 108 (e), that is, a signal in which the 188-byte MPEG packet valid period becomes “H” and the parity section of the 16-byte RS code becomes “L”, What is necessary is just to comprise the tuning circuit 1403 of FIG.

In this embodiment, the PN generation in the de-randomizing circuit 1407 is bit serial, but it may be an 8-bit parallel PN generation. In that case, the P / S conversion circuit 20030 of FIG.
And the S / P conversion circuit 20031 can be eliminated.

(Embodiment 15) Embodiment 1 of the present invention
5 will be described with reference to the drawings. FIG. 41 is a block diagram showing a configuration of the error correction circuit 1501 according to the present embodiment. An error correction circuit 1501 shown in FIG. 41 has a different internal configuration as indicated by a thick solid line. Speed conversion circuit 1502 and tuning circuit 150
3 is newly provided, and the speed conversion circuit 1502 is configured to be controlled by a slot selection signal output from the channel selection circuit 1503. The other blocks, that is, the functions of the Viterbi decoder 20002 to the RS decoding circuit 2008 and the transmission control information decoding circuit 20090 are the same as those shown in FIG.

The error correction circuit 15 configured as described above
01 and its operation will be described. However, the description before the input to the speed conversion circuit 1502 is as shown in the conventional example, and the description is omitted.

FIG. 42 is a block diagram showing a configuration example of the speed conversion circuit 1502. Speed conversion circuit 15 indicated by a dotted line
02 includes a write address generation circuit 1504, a read address generation circuit 1505, and a memory circuit 1506. Note that the memory circuit 1506 of the present embodiment uses a memory area of 24 slots in order to perform TS selection and speed conversion. FIG. 42 also shows a transmission control information decoding circuit 20010 and a channel selection circuit 1503.

As described in the problem to be solved by the invention, the conventional speed conversion circuit 20009 selects an TS and performs speed conversion using an unnecessary memory area. The speed conversion circuit 1502 of the present embodiment is configured to solve this problem. Hereinafter, the operation of the speed conversion circuit 1502 of the present embodiment will be described.

As shown in the conventional example, the speed conversion circuit 1
As shown in FIG. 108 (d), the data sequence input to 502 is as follows: TS1: <high-layer image> TC-8PSK: 22 slots <low-layer image> QPSK (r) per frame (48 slots) = 1/2): 2 slots (including dummy 1 slot) TS2: <high-layer image> TC-8PSK: 20 slots <low-layer image> BPSK (r = 1/2): 4 slots (including dummy) (3 slots) are input.

When channel selection information is input from an MPEG decoder (not shown) to the channel selection circuit 1503 in FIG. 42, the channel selection circuit 1503 is output from the transmission control information decoding circuit 20010 as in the conventional example. A slot selection signal for selecting a TS is output to the speed conversion circuit 1502 based on the slot number information. In the conventional example, as shown in FIGS. 114 to 117, the speed conversion circuit 20009 writes and reads out the entirety of the input 48-slot input data sequence to the memory circuit 20036 of FIG.

On the other hand, in the present embodiment, a selected TS, that is, a data sequence of only 24 slots / frame in this example, is written to the memory circuit 1506 by the slot selection signal output from the tuning circuit 1503. Is controlled to be performed. Therefore, the write address generation circuit 1504 generates only an address corresponding to the selected slot of 1 TS and outputs the generated address to the memory circuit 1506. The address of the slot corresponding to the TS that is not selected is free-run.

In addition, a slot selection signal output from the tuning circuit 1503 controls the data circuit of only the selected 1TS to be continuously read from the memory circuit 1506. For this reason, the read address generation circuit 1505 stores only the address corresponding to the selected slot of 1 TS at half the writing speed (= 24/48).
And outputs it to the memory circuit 1506. Note that the address of the slot corresponding to the TS that is not selected is not generated and is skipped.

By the above operation, the speed conversion circuit 1502
The output data series from is the same as the conventional example as shown in FIG. Also, the read address generation circuit 15
As shown in FIG. 108 (e), the validity period of the 188-byte MPEG packet becomes "H" for each 204-byte slot output from the memory circuit 1506, as shown in FIG. , An enable signal which becomes “L” in the parity section of
Output to the EG decoder.

With the above configuration, the speed conversion circuit 1502 of the present embodiment reduces the memory area to be used by half by writing and reading the input data sequence of only one selected TS to the memory circuit 1506. can do.

In the above embodiment, TS1, TS1,
Both of them occupy 24 slots per frame. For example, if the maximum number of slots per frame occupied by 1TS is determined in the BS digital broadcasting standard, the memory of the maximum number of slots is used. An area may be prepared, and the memory area used by the memory circuit 1506 is not limited to 24 slots as in the above embodiment.

In the above embodiment, the data sequence input to the speed conversion circuit 1502 is one frame (48
Each slot consists of two types of TS, and one type of T
S is to be tuned. Here, for example, TS1: <high-layer image> TC-8PSK: 14 slots <low-layer image> QPSK (r = 1/2): 2 slots (of which, one dummy slot) TS2: <high-layer image> TC-8PSK: 12 slots <Low-layer image> QPSK (r = 3/4): 4 slots (including one dummy slot) TS3: <High-layer image> TC-8PSK: 12 slots <Low-layer image> BPSK (r = 1/2): Consider a case where three types of TSs of 4 slots (including 3 dummy slots) are input.

When one type of TS is selected, only the selected one TS is stored in the memory circuit 1506 as described above.
, Speed conversion, and reading at a speed of 16/48 = 1/3. When two types of TS are selected, for example, when one TS is displayed on a monitor and the other 1TS is video-recorded, the selected 2T is displayed.
Only S may be written into the memory circuit 1506, speed converted, and read at a speed of 32/48 = 2/3. In this case, in the BS digital broadcasting standard,
If the maximum number of slots per frame occupied by one TS is determined, a memory area of the maximum number of slots × 2 slots may be prepared. In addition, for example, eight types of T
The same applies when S is input and four types of TS are selected.

As the speed conversion circuit, a configuration is also conceivable in which a plurality of tuned TSs are speed-converted and output continuously in parallel. FIG. 43 shows a speed conversion circuit 150 having a parallel output.
8 is a block diagram illustrating a configuration of an error correction circuit 1507 having 8; FIG. In the error correction circuit 1507 shown in FIG. 43, the internal structures of the speed conversion circuit 1508 and the channel selection circuit 1509 are the same as those of the speed conversion circuit 1502 and the channel selection circuit 1 shown in FIG.
503 is different from the internal configuration. The other blocks, that is, the functions of the Viterbi decoder 20002 to the RS decoding circuit 20008 and the transmission control information decoding circuit 20010 are the same as those shown in FIG.

FIG. 44 is a block diagram showing a configuration example of the speed conversion circuit 1508. Speed conversion circuit 15 indicated by a dotted line
08 includes a write address generation circuit 1510, a read address generation circuit 1511, and a memory circuit 1512. Note that the memory circuit 1512 of this embodiment uses a memory area of 32 slots to perform TS selection and speed conversion. FIG. 44 also shows a transmission control information decoding circuit 20010 and a channel selection circuit 1509.

Here, the data sequence input to the speed conversion circuit 1508 is expressed as follows: TS1: <high-layer image> TC-8PSK: 14 slots <low-layer image> QPSK (r = 1/2): 2 slots (including dummy 1 slot) TS2: <high-layer image> TC-8PSK: 12 slots <low-layer image> QPSK (r = 3/4): 4 slots (including dummy 1) Slot) TS3: <high-layer image> TC-8PSK: 12 slots <low-layer image> BPSK (r = 1/2): 4 slots (including 3 dummy slots) think of.

When two types of TSs are selected, for example, when one TS is displayed on a monitor and another one is video-recorded, only the selected two TSs are stored in the memory circuit 15.
12 and perform speed conversion to obtain 1/3 (= 16 /
It is sufficient to read 2TSs in parallel at the speed of 48). For example, the same applies to a case where eight types of TSs are input and four types of TSs are selected.

In the above embodiment, the speed conversion circuit 1502 or the speed conversion circuit 1508 sets one slot = 204 bytes, and reads and writes 16 bytes of parity bytes in the memory circuit 1506 or the memory circuit 1512.
It is configured to output with an enable signal. Not limited to this configuration, the parity byte 16 bytes
A configuration in which the speed conversion is performed without reading / writing from / to the memory circuit 1512 or the memory circuit 1512 is also conceivable. In this case, the used area of the memory circuit 1506 or the memory circuit 1512 is further increased by 18
8/204 = 47/51, and the read address generation circuit 1505 or the read address generation circuit 151
1 eliminates the need to generate an enable signal. 47 /
The speed conversion of 51 can be easily realized by providing a counter circuit for outputting a ripple carry (carry) signal when the count value reaches 51, for example, and inputting 47 to this counter circuit. In this case, the ripple carry signal is output at a speed of 47/51 of the input.

(Embodiment 16) Embodiment 1 of the present invention
6 will be described with reference to the drawings. FIG. 45 is a block diagram showing a configuration of the error correction circuit 1601 in the present embodiment. The error correction circuit 1601 shown in FIG.
The internal configurations of the interleave circuit 1302, the speed conversion circuit 1602, and the tuning circuit 1603 are different, and the de-interleave circuit 1302 and the speed conversion circuit 1502 are controlled by the slot selection signal output from the tuning circuit 1503. Is the feature. The other blocks, that is, the Viterbi decoder 20002 to the symbol / byte conversion circuit 20004, the MPEG synchronization byte / dummy slot insertion circuit 20006 to the RS decoding circuit 20008, and the transmission control information decoding circuit 20010 are the same as those shown in FIG. is there. The de-interleave circuit 1302 is the same as that shown in FIG.

The error correction circuit 16 configured as described above
01 and its operation will be described. However, before the input to the de-interleave circuit 1302, the description is omitted because it is as shown in the conventional example.

As described in the thirteenth embodiment, FIG.
The deinterleaved data shown in FIG.
Output from the interleave circuit 1302. The number of effective slots per frame of one TS is 24.

The byte data series output from the de-interleave circuit 1302 and shown in FIG. 35B is similar to the conventional example in the MPEG synchronization byte / dummy
Slot insertion circuit 20006, de-randomizing circuit 2
[0007] The signal is processed by the RS decoding circuit 20008 and output to the speed conversion circuit 1602. However, FIG. 108 (c)
35 (b), the number of effective slots per frame is 24 in the case of the present embodiment.
It is. Therefore, the MPEG synchronization byte / dummy slot insertion circuit 20006 and the de-randomizing circuit 2000
7 and the RS decoding circuit 20008, the same data sequence as in FIG.

FIG. 46 is a block diagram showing a configuration example of the speed conversion circuit 1602. Speed conversion circuit 16 indicated by a dotted line
02 has a write address generation circuit 1604, a read address generation circuit 1605, and a memory circuit 1606. Note that the memory circuit 1606 of the present embodiment uses a memory area of 24 slots to perform TS selection and speed conversion. FIG. 46 shows a transmission control information decoding circuit 20010 and a channel selection circuit 1603.

When channel selection information is input from an MPEG decoder (not shown) to the channel selection circuit 1603, the channel selection circuit 1603
Is a transmission control information decoding circuit 2001
A slot selection signal for selecting a TS is output to the speed conversion circuit 1602 from the slot number information output from 0. In the same manner as in the fifteenth embodiment, the 1TS selected by the slot selection signal output from the tuning circuit 1603, in this case, the data sequence of only the valid slots of 24 slots / frame, is used as the memory circuit 1606.
Is controlled to perform writing. Therefore, the write address generation circuit 1604 generates only an address corresponding to the selected slot of 1 TS, and the memory circuit 16
06 is output. Note that TSs not selected, that is, 2
The address of the slot corresponding to the invalid slot of 4 slots / frame is free-run.

In addition, control is performed so that the data sequence of only 1TS selected by the slot selection signal is continuously read from the memory circuit 1606 in the same manner as in the fifteenth embodiment. Therefore, the read address generation circuit 16
05 generates only an address corresponding to the selected slot of 1TS at a writing speed of 24/48 = 1/2 and outputs it to the memory circuit 1606. Note that the address of the slot corresponding to the TS that is not selected is not generated and is skipped.

As described above, the output data series from the speed conversion circuit 1602 is the same as the conventional example as shown in FIG. Also, the read address generation circuit 160
5 indicates that the validity period of the 188-byte MPEG packet as shown in FIG. 108 (e) is “H” for each 204-byte slot output from the memory circuit A 16-byte parity section generates an enable signal of “L”, and an MP (not shown)
Output to the EG decoder.

[0364] With the above configuration, when the input data sequence of only one TS already selected by the de-interleave circuit 1302 is input, the speed conversion circuit 1602 of the present embodiment stores the data sequence of only one TS in the memory. Circuit 16
By writing to and reading from 06, the memory area used can be reduced by half.

[0365] In the above embodiment, TS1, TS
Both of them occupy 24 slots per frame. For example, if the maximum number of slots per frame occupied by 1TS is determined in the BS digital broadcasting standard, the memory of the maximum number of slots is used. An area may be prepared, and the memory area used by the memory circuit 1606 is not limited to 24 slots as in the above embodiment.

Also, in the above embodiment, the data sequence input to speed conversion circuit 1602 is one frame (48
Each slot consists of two types of TS, and one type of T
S is to be tuned. Here, for example, TS1: <high-layer image> TC-8PSK: 14 slots <low-layer image> QPSK (r = 1/2): 2 slots (including dummy 1 slot) TS2: <high-layer image> TC-8PSK: 12 slots <Low-layer image> QPSK (r = 3/4): 4 slots (including one dummy slot) TS3: <High-layer image> TC-8PSK: 12 slots <Low-layer image> BPSK (r = 1/2): Consider a case where three types of TSs of 4 slots (including 3 dummy slots) are input. One kind of T
When S is selected, 1T selected as described above is used.
Only S may be written to the memory circuit 1606, speed converted, and read at a speed of 16/48 = 1/3. When two types of TSs are selected, for example, one TS is displayed on a monitor and the other 1TS is video-recorded, and only the selected two TSs are written into the memory circuit 1606 to perform speed conversion. , 32/48 = 2/3. In this case, if the maximum number of slots per frame occupied by one TS is determined in the BS digital broadcasting standard, a memory area of the maximum number of slots × 2 slots may be prepared.
In addition, the same applies to a case where, for example, eight types of TSs are input and four types of TSs are selected.

[0367] As the speed conversion circuit, a configuration is also conceivable in which a plurality of tuned TSs are speed-converted and output continuously in parallel. FIG. 47 shows a speed conversion circuit 160 having a parallel output.
9 is a block diagram illustrating a configuration of an error correction circuit 1607 in the case of having eight. The speed conversion circuit 1608 converts the speed of a plurality of TSs already selected by the de-interleave circuit 1302 and outputs the TS continuously and in parallel. An error correction circuit 1607 shown in FIG. 47 includes a de-interleave circuit 1302, a speed conversion circuit 1608, and a channel selection circuit 1
The internal configuration of a deinterleave circuit 20005, a speed conversion circuit 1502, and a tuning circuit 150 shown in FIG.
3 is different from the internal configuration. Other blocks, that is, a Viterbi decoder 20002, a symbol / byte conversion circuit 20004, an MPEG synchronization byte / dummy slot insertion circuit 20006, and a de-randomizing circuit 20
007, the RS decoding circuit 20008, and the transmission control information decoding circuit 20090 are the same as those shown in FIG.

FIG. 48 is a block diagram showing a configuration example of the speed conversion circuit 1608. Speed conversion circuit 16 indicated by a dotted line
08 includes a write address generation circuit 1610, a read address generation circuit 1611, and a memory circuit 1612. Note that the memory circuit 1612 of this embodiment uses a memory area of 32 slots to perform TS selection and speed conversion. FIG. 48 shows a transmission control information decoding circuit 20010 and a channel selection circuit 1609.

Here, the data sequence input to the speed conversion circuit 1608 is expressed as follows: TS1: <high-layer image> TC-8PSK: 14 slots <low-layer image> QPSK (r = 1/2): 2 slots (including dummy 1 slot) TS2: <high-layer image> TC-8PSK: 12 slots <low-layer image> QPSK (r = 3/4): 4 slots (including dummy 1) Slot) TS3: <high-layer image> TC-8PSK: 12 slots <low-layer image> BPSK (r = 1/2): 4 slots (including 3 dummy slots) think of.

[0370] When two types of TS are selected, for example, when one TS is displayed on a monitor and the other one is video-recorded, only the two TSs already selected by the de-interleave circuit 1302 are stored in the memory circuit. Write to 1612, perform speed conversion, 2T at 16/48 = 1/3 speed
S may be read in parallel. In addition, for example, 8 types of TS
Is input, and the same applies to a case where four types of TS are selected.

In the above embodiment, the speed conversion circuit 1602 or 1608 reads / writes 1 slot = 204 bytes, 16 bytes of parity bytes to / from the memory circuit 1606 or 1612, and outputs it with an enable signal. Configuration. Not limited to this configuration, the parity byte 16 bytes may be stored in the memory circuit 160
A configuration in which speed conversion is performed without reading / writing data from / to the memory circuit 16 or the memory circuit 1612 is also conceivable. In this case, the used area of the memory circuit 1606 or the memory circuit 1612 is further increased by 18
8/204 = 47/51, and the read address generation circuit 1605 or the read address generation circuit 161
1 eliminates the need to generate an enable signal. 47
For the speed conversion of / 51, for example, when the count value is 51
, A counter circuit for outputting a ripple carry (carry) signal is provided, and this counter circuit can be easily realized by inputting 47 signals at a time. In this case, the ripple carry signal is output at a speed of 47/51 of the input.

(Embodiment 17) Embodiment 1 of the present invention
7 will be described with reference to the drawings. In the embodiment described below,
It is assumed that “no TMCC”, that is, the case where the superframe structure is constant over time. The operation of the error correction circuit according to the present embodiment is basically the same as that of the error correction circuits described in the first to sixteenth embodiments except that various control information is periodically generated. Therefore, the description of the same operation is omitted.

FIG. 49 is a block diagram of the error correction coding device 17 on the transmission side.
FIG. 2 is a block diagram showing an example of the configuration of FIG. The error correction coding apparatus 1701 shown in FIG.
, RS encoding circuit 10003, and randomizing circuit 1
0004, an interleave circuit 10005, a byte / symbol conversion circuit 10006, a convolutional encoder 10007, and a mapping circuit 10008. Instead of the conventional transmission control information generation circuit 10009 shown in FIG. It is characterized in that a data information generation circuit 1702 is provided. Note that the TS multiplexing circuit 10002
Each function of the mapping circuit 10008 is the same as that shown in FIG.

FIG. 50 is a data arrangement diagram showing an output data sequence up to the randomizing circuit 10004 in the error correction encoding device 1701. In this data arrangement, the flow is exactly the same as in the case of "with TMCC" shown in FIG. However, as shown in the superframe configuration of FIG. 50D, the first byte of each slot is replaced with a signal of 12 bytes per frame instead of TMCC after interleaving. These 12-byte signals include W1 of the previous TAB signal 2 bytes, data other than video,
For example, it is W2 or W3 of 8 bytes of character multiplex data and 2 bytes of a rear TAB signal.

FIG. 51 shows the byte / symbol conversion circuit 10.
FIG. 8 is a data arrangement diagram in a byte data sequence having a superframe structure input to 006. As shown in FIG. 87, the feature is that TMCC actual data, that is, 8 bytes per frame is replaced with data other than video data, for example, 8 bytes of character multiplexed data, as compared with the case of “with TMCC”. Except for this, the super frame structure is the same as that of FIG. 87. That is, the TAB / data information generation circuit 1702 of FIG. 49 uses a 12-byte synchronization signal for each frame, a 2-byte TAB signal (W1), 8-byte character multiplexed data other than video, and a 2-byte TAB signal (W
2 or W3) Generate in the order of 2 bytes. Also, TAB /
The data information generation circuit 1702 periodically generates and outputs a constant modulation parameter.

FIG. 52 shows the byte / symbol conversion circuit 10.
FIG. 9 is an explanatory diagram showing an example of the number of slots in each transmission mode in a byte data sequence per frame of a superframe structure input to 006. As shown in this figure, TC-8PSK (r = ２): 42 slots QPSK (r =＝): 0 slots QPSK (r = １ ／): 2 slots (of which, 1 dummy slot) BPSK (R = 1/2): 4 slots (including 3 dummy slots), and the number of slots does not change with time.

FIG. 53 is a diagram showing the data arrangement per frame in which the flow of signals from the input to the output of the error correction coding device 1701 is summarized. The "TMCC" in FIG.
53 (d) shows that the actual data of the TMCC, that is, the portion of 128 symbols / frame is changed to a symbol in which 8 bytes of character multiplexed data are convolutionally encoded. Other parts are the same.

Next, an error correction circuit for performing error correction decoding on a data sequence that has been error correction encoded by the error correction encoding device 1701 will be described below with reference to the drawings.

FIG. 54 shows the case of “without TMCC”, ie, the case of “with TMCC” as described in the first embodiment, that is, the error correction circuit 170 of the seventeenth embodiment.
3 is a block diagram illustrating a configuration example of FIG. In this error correction circuit 1703, blocks shown by thick solid lines are different from the conventional example. In the error correction circuit 1703 of the present embodiment,
A Viterbi decoder 102 controlled by a switching control signal and a Viterbi decoder control circuit 103 for generating a switching control signal are provided, and control signal generation is performed instead of the transmission control information decoding circuit 20010 in the first to sixteenth embodiments. Circuit 1704
Is provided, and a channel selection circuit 1705 having an internal configuration different from those of the first to sixteenth embodiments is provided. The other blocks, that is, the high / low hierarchy selection signal generation circuit 20003 to the speed conversion circuit 200009 are the same as those shown in FIG.

An operation of the error correction circuit 1703 having such a configuration will be described. The data sequence error-correction-coded by the transmission-side error correction coding device 1701 as shown in FIG. 49 is quadrature-modulated by a quadrature modulator (not shown) and transmitted through a satellite transmission path. The signal transmitted from the transponder is input to a PSK demodulator (not shown) on the receiving side and PSK demodulated. The constraint length of the convolution circuit 10014 shown in FIG. 91 is 7, and the TAB signal section is transmitted by BPSK.
2 bits), the first 12 symbols are indeterminate,
The remaining 20 symbols are w1 (= xxxE) as shown in FIG.
CD28h), w2 (= xxx0B677h), w3 (= xxxF4988h)
). The PSK demodulator performs demodulation by delay detection when the tuning is switched by the tuning information.
Detect w1, w2, w3. In this way, the PSK demodulator detects the superframe synchronization and the absolute phase, and after the detection, performs synchronous detection, and outputs the PSK demodulated data and the superframe synchronization signal to the error correction circuit 1703 in FIG.

In the error correction circuit 1703, the control signal generation circuit 1704 operates according to the superframe synchronization signal output from the PSK demodulator, and transmits various control information, ie, transmission mode / slot information, transmission mode, and dummy slot information. Generate and output at a fixed cycle. Also, the control signal generation circuit 1704 extracts and outputs only the portion of the character multiplexed data of 64 bits (64 symbols) output from the Viterbi decoder 102 for each frame.

The Viterbi decoder control circuit 103 generates a switching control signal based on the transmission mode / slot information output from the control signal generation circuit 1704 and outputs the same to the Viterbi decoder 102, as in the first embodiment. . Viterbi decoder 102 performs the same operation as in the first embodiment shown in FIG.

The error correction capability of the error correction circuit 1703 described above is secured to the same degree as the error correction circuit of the first embodiment. Note that, similarly to Embodiment 1, when the modulation multi-level number after transmission mode switching is larger than before transmission mode switching,
Alternatively, the switching control signal may be generated only when the modulation multi-level number is the same and the coding rate is large.

Also, as in the first embodiment, when switching the transmission mode before and after the superframe synchronization signal (BPSK: r = ｒ), the Viterbi decoder control circuit 103
May not be configured to generate the switching control signal.
In this case, a Viterbi decoding control method using the property of the fixed symbol sequence can be considered. This will be described in Embodiments 18 and 19.

(Embodiment 18) Embodiment 1 of the present invention
8 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 55 is a diagram showing the “TM” described in the second embodiment.
It is a block diagram which shows the example of a structure of the error correction circuit 1801 in the case of "without TMCC" with respect to the case of "with CC". The error correction circuit 1801 is different from the error correction circuit 201 of the second embodiment shown in FIG. 5 in that a channel selection circuit 1705 having a different internal configuration is provided, and a control signal generation circuit is substituted for the transmission control information decoding circuit 20010. 1704
Is provided. Other blocks,
That is, the Viterbi decoder 202 to the Viterbi decoder control circuit 20
3. The functions of the high / low hierarchy selection signal generation circuit 20003 to the speed conversion circuit 200009 are the same as those shown in FIG.

In the error correction circuit 1801 of this embodiment, the Viterbi decoder control circuit 203 uses the transmission mode / slot information output from the control signal generation circuit 1704 to determine the final state signal in the same manner as in the second embodiment. Is generated and output to the Viterbi decoder 202 in FIG. The Viterbi decoder 202 performs the same operation as in the second embodiment as shown in FIG. The control signal generation circuit 1704 outputs 64 bits (6 bits) to each frame output from the Viterbi decoder 202.
Only the character multiplexed data portion (4 symbols) is extracted and output.

The error correction capability of the error correction circuit 1801 described above is secured to the same degree as the error correction circuit of the second embodiment. As in the second embodiment, the Viterbi decoder control circuit 203 can arbitrarily select a symbol period for generating a fixed state signal from 1 symbol or more and up to 10 symbols, and select any symbol. It is optional.

(Embodiment 19) Embodiment 1 of the present invention
9 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 56 is a block diagram showing a configuration example of the error correction circuit 1901 in the case of "without TMCC" in contrast to "with TMCC" described in the third embodiment. This error correction circuit 1901 is different from the error correction circuit 301 of the third embodiment shown in FIG. 8 in that a channel selection circuit 1705 having a different internal configuration is provided, and a control signal generation circuit is provided instead of the transmission control information decoding circuit 20010. 1704
Is provided. Other blocks,
That is, the Viterbi decoder 302 to the Viterbi decoder control circuit 30
3. Each function of the high / low hierarchy selection signal generation circuit 20003 to the speed conversion circuit 200009 is the same as that shown in FIG.

In the error correction circuit 1901 of the present embodiment, as in the case of the third embodiment, the Viterbi decoder control circuit 303 uses the transmission mode / slot information output from the control signal generation circuit 1704 to generate a fixed branch. A signal is generated and output to the Viterbi decoder 302 in FIG.
Viterbi decoder 302 performs the same operation as in the third embodiment as shown in FIG. The control signal generation circuit 170
4 is each frame 6 output from the Viterbi decoder 302
Only the portion of 4-bit (64 symbols) character multiplexed data is extracted and output.

The error correction capability of the error correction circuit 1901 described above is secured to the same degree as the error correction circuit of the third embodiment.

(Embodiment 20) Embodiment 2 of the present invention
The error correction circuit at 0 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 57 is a diagram showing the “TM” described in the fourth embodiment.
FIG. 14 is a block diagram illustrating a configuration example of an error correction circuit 2001 in the case of “without CC” versus “with CC”. This error correction circuit 2001 is different from the error correction circuit 401 of the fourth embodiment shown in FIG. 11 in that a channel selection circuit 1705 having a different internal configuration is provided, and a control signal generation circuit is provided instead of the transmission control information decoding circuit 20010. A feature is that a circuit 1704 is provided. Other blocks, that is, Viterbi decoder 402 to Viterbi decoder control circuit 403, high / low hierarchical selection signal generation circuit 20003 to speed conversion circuit 2
Each function of 0009 is the same as that shown in FIG.

In the error correction circuit 2001 of this embodiment, the Viterbi decoder control circuit 403 converts the state reduction signal based on the transmission mode / slot information output from the control signal generation circuit 1704 in the same manner as in the fourth embodiment. It is generated and output to the Viterbi decoder 402 in FIG. Viterbi decoder 402 performs the same operation as in the third embodiment as shown in FIG. Further, the control signal generation circuit 1704 extracts and outputs only a portion of the character multiplexed data of 64 bits (64 symbols) output from the Viterbi decoder 402 for each frame.

The error correction capability of the error correction circuit 2001 described above is secured to the same degree as the error correction circuit of the fourth embodiment.

(Embodiment 21) Embodiment 2 of the present invention
1 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 58 is a diagram showing the “TM” described in the fifth embodiment.
FIG. 14 is a block diagram illustrating a configuration example of an error correction circuit 2101 in the case of “without CC” versus “with CC”. This error correction circuit 2001 is different from the error correction circuit 501 of the fifth embodiment shown in FIG. 14 in that a channel selection circuit 1705 having a different internal configuration is provided, and a control signal generation circuit is provided in place of the transmission control information decoding circuit 20010. 1704 is provided. Other blocks, that is, input symbol conversion circuit 506, Viterbi decoder control circuit 50
3. Viterbi decoder 20002-speed conversion circuit 200009
Are the same as those shown in FIG.

In error correction circuit 2101 of the present embodiment, Viterbi decoder control circuit 503 generates a symbol coordinate conversion signal based on the transmission mode / slot information output from control signal generation circuit 1704, and FIG. The output to input symbol conversion circuit 506 is the same as in the fifth embodiment. The input symbol conversion circuit 506
As shown in FIG. 16, the same operation as in the fifth embodiment is performed. Further, the control signal generation circuit 1704 extracts and outputs only the portion of the character multiplexed data of 64 bits (64 symbols) output from the Viterbi decoder 502 for each frame.

The error correction capability of the error correction circuit 2101 described above is secured to the same degree as the error correction circuit of the fifth embodiment.

(Embodiment 22) Embodiment 2 of the present invention
2 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 59 is a flowchart showing the operation of “TM” described in the sixth embodiment.
FIG. 21 is a block diagram illustrating a configuration example of an error correction circuit 2201 in the case of “without CC” versus “with CC”. This error correction circuit 2201 is different from the error correction circuit 601 of the sixth embodiment shown in FIG. 19 in that a channel selection circuit 1705 having a different internal configuration is provided. A feature is that a circuit 1704 is provided. Other blocks, that is, Viterbi decoder 602 to Viterbi decoder control circuit 603, high / low hierarchical selection signal generation circuit 20003 to speed conversion circuit 2
Each function of 0009 is the same as that shown in FIG.

In the error correction circuit 2201 of the present embodiment, the Viterbi decoder control circuit 603 uses the transmission mode / slot information output from the control signal generation circuit 1704 to generate a definite state signal in the same manner as in the sixth embodiment. A fixed branch signal is generated and output to the Viterbi decoder 602 in FIG. Viterbi decoder 602 performs the same operation as in the sixth embodiment. Also, the control signal generation circuit 1704 extracts and outputs only the portion of the character multiplexed data of 64 bits (64 symbols) output from the Viterbi decoder 602 for each frame.

[0404] The error correction capability of the error correction circuit 2201 described above is secured to the same degree as the error correction circuit of the sixth embodiment.

(Embodiment 23) Embodiment 2 of the present invention
3 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 60 is a flowchart showing the operation of “TM” described in the seventh embodiment.
FIG. 18 is a block diagram illustrating a configuration example of an error correction circuit 2301 in the case of “without CC” versus “with CC”. This error correction circuit 2301 is different from the error correction circuit 701 of the seventh embodiment shown in FIG. 21 in that a channel selection circuit 1705 having a different internal configuration is provided, and a control signal generation circuit is substituted for the transmission control information decoding circuit 20010. A feature is that a circuit 1704 is provided. The functions of the other blocks, that is, the input symbol conversion circuit 506, the Viterbi decoder 702 to the Viterbi decoder control circuit 703, and the high / low hierarchical selection signal generation circuit 20003 to the speed conversion circuit 200009 are the same as those shown in FIG. It is.

In the error correction circuit 2301 according to the present embodiment, the Viterbi decoder control circuit 703 uses the transmission mode / slot information output from the control signal generation circuit 1704 in the same manner as in the seventh embodiment to determine the symbol coordinates. A converted signal is generated and output to the input symbol conversion circuit 506, and a fixed branch signal is generated and output to the Viterbi decoder 702 in FIG. The input symbol conversion circuit 506 and the Viterbi decoder 702 perform the same operation as in the seventh embodiment. Also, the control signal generation circuit 1704 extracts and outputs only the portion of the character multiplexed data of 64 bits (64 symbols) output from the Viterbi decoder 702 for each frame.

[0408] The error correction capability of the error correction circuit 2301 described above is secured to the same degree as the error correction circuit of the seventh embodiment.

(Embodiment 24) Embodiment 2 of the present invention
4 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 61 is a drawing showing the “TM” described in the eighth embodiment.
FIG. 21 is a block diagram illustrating a configuration example of an error correction circuit 2401 in the case of “without CC” versus “with CC”. This error correction circuit 2401 is different from the error correction circuit 801 of the eighth embodiment shown in FIG. 23 in that a channel selection circuit 1705 having a different internal configuration is provided and a control signal generation circuit is substituted for the transmission control information decoding circuit 20010. A feature is that a circuit 1704 is provided. Other blocks, that is, Viterbi decoder 802 to Viterbi decoder control circuit 803, high / low hierarchical selection signal generation circuit 20003 to speed conversion circuit 2
Each function of 0009 is the same as that shown in FIG.

[0411] In the error correction circuit 2401 of the present embodiment, the Viterbi decoder control circuit 803 determines the definite state based on the transmission mode / slot information output from the control signal generation circuit 1704, as in the case of the eighth embodiment. The signal and the state reduction signal are generated and the Viterbi decoder 802 of FIG. 24 is generated.
Output to Viterbi decoder 802 performs the same operation as in the eighth embodiment. Also, the control signal generation circuit 1704
Only the 64-bit (64 symbols) character multiplexed data portion of each frame output from the Viterbi decoder 802 is extracted and output.

[0412] The error correction capability of the error correction circuit 2401 described above is secured to the same degree as the error correction circuit of the eighth embodiment.

(Embodiment 25) Embodiment 2 of the present invention
5 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 62 is a diagram showing the “TM” described in the ninth embodiment.
FIG. 19 is a block diagram illustrating a configuration example of an error correction circuit 2501 in the case of “without CC” versus “with CC”. The error correction circuit 2501 is different from the error correction circuit 901 of the ninth embodiment shown in FIG. 25 in that a channel selection circuit 1705 having a different internal configuration is provided and a control signal generation circuit is substituted for the transmission control information decoding circuit 20010. A feature is that a circuit 1704 is provided. Other blocks, that is, Viterbi decoder 902 to Viterbi decoder control circuit 903, high / low hierarchical selection signal generation circuit 20003 to speed conversion circuit 2
Each function of 0009 is the same as that shown in FIG.

[0415] In the error correction circuit 2501 of the present embodiment, the Viterbi decoder control circuit 903 uses the transmission mode / slot information output from the control signal generation circuit 1704 to set the fixed branch in the same manner as in the ninth embodiment. A signal and a state reduction signal are generated, and the Viterbi decoder 9 shown in FIG.
02 is output. Viterbi decoder 902 performs the same operation as in the ninth embodiment. Also, the control signal generation circuit 1704
Represents each frame 64 output from the Viterbi decoder 902
Only the bit (64 symbols) character multiplexed data portion is extracted and output.

[0416] The error correction capability of the error correction circuit 2501 described above is secured to the same degree as the error correction circuit of the ninth embodiment.

(Embodiment 26) Embodiment 2 of the present invention
6 will be described with reference to the drawings. Note that, also in the present embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 63 is a block diagram of “T” described in the tenth embodiment.
FIG. 19 is a block diagram illustrating a configuration example of an error correction circuit 2601 when “without MCC” is provided for “with MCC”. This error correction circuit 2601 is similar to that of the first embodiment shown in FIG.
0 error correction circuit 1001 is provided with a tuning circuit 1705 having a different internal configuration, and the control signal generation circuit 170 is replaced with the transmission control information decoding circuit 20010.
4 is provided. Other blocks, ie, input symbol conversion circuit 506, Viterbi decoder 1
002 to Viterbi decoder control circuit 1003 and high / low hierarchical selection signal generation circuit 20003 to speed conversion circuit 200009 have the same functions as those shown in FIG.

[0419] In the error correction circuit 2601 of the present embodiment, the Viterbi decoder control circuit 1003 uses the transmission mode / slot information output from the control signal generation circuit 1704 in the same manner as in the tenth embodiment to determine the symbol coordinates. A converted signal is generated and output to the input symbol conversion circuit 506, and a state reduction signal is generated and output to the Viterbi decoder 1002 in FIG. Input symbol conversion circuit 506 and Viterbi decoder 1002 perform the same operations as in the tenth embodiment. The control signal generation circuit 1704 outputs 64 bits (6 bits) to each frame output from the Viterbi decoder 1002.
Only the character multiplexed data portion (4 symbols) is extracted and output.

[0420] The error correction capability of the error correction circuit 2601 described above is secured to the same degree as the error correction circuit of the tenth embodiment.

(Embodiment 27) Embodiment 2 of the present invention
7 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 64 is a drawing showing the "T" described in the eleventh embodiment.
FIG. 18 is a block diagram illustrating a configuration example of an error correction circuit 2701 in the case of “without MCC” with respect to “with MCC”. This error correction circuit 2701 is different from the first embodiment shown in FIG.
In one error correction circuit 1101, a channel selection circuit 1705 having a different internal configuration is provided, and a control signal generation circuit 170 is provided instead of the transmission control information decoding circuit 20010.
4 is provided. The other blocks, that is, the functions of the Viterbi decoder 1102, the Viterbi decoder control circuit 1103, the high / low hierarchical selection signal generation circuit 20003, and the speed conversion circuit 200009 are the same as those shown in FIG.

In the error correction circuit 2701 of this embodiment, the Viterbi decoder control circuit 1103 determines the transmission mode / slot information output from the control signal generation circuit 1704 in the same manner as in the eleventh embodiment. A state signal, a fixed branch signal, and a state reduction signal are generated and output to the Viterbi decoder 1102 in FIG. Viterbi decoder 1102 performs the same operation as in the eleventh embodiment. Also,
The control signal generation circuit 1704 extracts and outputs only the portion of the character multiplexed data of 64 bits (64 symbols) output from the Viterbi decoder 1102 for each frame.

[0424] The error correction capability of the error correction circuit 2701 described above is secured to the same degree as the error correction circuit of the eleventh embodiment.

(Embodiment 28) Embodiment 2 of the present invention
8 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 65 is a view showing the "T" described in the twelfth embodiment.
FIG. 18 is a block diagram illustrating a configuration example of an error correction circuit 2801 in the case of “without MCC” for “with MCC”. This error correction circuit 2801 is similar to that of the first embodiment shown in FIG.
In the second error correction circuit 1201, a channel selection circuit 1705 having a different internal configuration is provided, and a control signal generation circuit 170 is provided instead of the transmission control information decoding circuit 20010.
4 is provided. Other blocks, ie, input symbol conversion circuit 506, Viterbi decoder 1
The respective functions of 202 to Viterbi decoder control circuit 1203, high / low hierarchical selection signal generation circuit 20003 to speed conversion circuit 200009 are the same as those shown in FIG.

In the error correction circuit 2801 of the present embodiment, the Viterbi decoder control circuit 1203 uses the transmission mode / slot information output from the control signal generation circuit 1704 in the same manner as in the twelfth embodiment to determine the symbol coordinates. A converted signal is generated and output to the input symbol conversion circuit 506, and a fixed branch signal and a state reduction signal are generated and output to the Viterbi decoder 1202 in FIG. The input symbol conversion circuit 506 and the Viterbi decoder 1202 perform the same operation as in the twelfth embodiment. Also, the control signal generation circuit 1704 extracts and outputs only the portion of the character multiplexed data of 64 bits (64 symbols) output from the Viterbi decoder 1202 for each frame.

The error correction capability of the error correction circuit 2801 described above is secured to the same degree as the error correction circuit of the twelfth embodiment.

(Embodiment 29) Embodiment 2 of the present invention
9 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 66 is a view showing the "T" described in the thirteenth embodiment.
FIG. 19 is a block diagram illustrating a configuration example of an error correction circuit 2901 in the case of “without MCC” with respect to “with MCC”. This error correction circuit 2901 is different from the first embodiment shown in FIG.
In the third error correction circuit 1301, a channel selection circuit 1705 having a different internal configuration is provided, and a control signal generation circuit 1701 is provided instead of the transmission control information decoding circuit 20010.
4 is provided. Other blocks, that is, a deinterleave circuit 1302, a Viterbi decoder 20002 to a symbol / byte conversion circuit 20004,
MPEG synchronization byte / dummy slot insertion circuit 200
Each function of 06 to speed conversion circuit 200009 is the same as that shown in FIG.

In the error correction circuit 2901 of the present embodiment, the relative TS / TS correspondence table shown in FIG. 84 and the relative TS / slot information shown in FIG. 83 are known and are temporally constant. Therefore, the channel selection circuit 1705 has a known relative TS / TS correspondence table and relative TS / slot information, generates a slot selection signal from the information, and outputs the signal to the de-interleave circuit 1302 in FIG. . The de-interleave circuit 1302 performs the same operation as in the thirteenth embodiment as shown in FIG.

The error correction capability of the error correction circuit 2901 described above is secured to the same degree as the error correction circuit of the thirteenth embodiment.

As in Embodiment 13, for example, B
If the maximum number of slots per frame occupied by 1TS is determined in the S digital broadcasting standard, a memory area of 2 banks of (maximum number of slots × 8 slots) may be prepared. The memory area used is not limited to two banks of 24 × 8 slots as in the thirteenth embodiment.

Also, as in the thirteenth embodiment, for example, TS1: <high-layer image> TC-8PSK: 14 slots <low-layer image> QPSK (r = 1/2): 2 slots (of which, dummy 1 Slot) TS2: <high-layer image> TC-8PSK: 12 slots <low-layer image> QPSK (r = 3/4): 4 slots (of which, one dummy slot) TS3: <high-layer image> TC- 8PSK: 12 slots <Low-level image> BPSK (r = 1/2): 4 slots (of which, 3 slots are dummy) A case is considered in which three types of TS are input. That is, 3TS is assigned to one transponder. When one type of TS is selected, as in the thirteenth embodiment, only the selected one TS may be written to the memory circuit 1306 and read. When two types of TS are selected,
For example, when one TS is to be displayed on a monitor and the other 1TS is to be video-recorded, only the selected 2TS may be written to the memory circuit 1306 and read. In this case, if the maximum number of slots per frame occupied by one TS is determined in the BS digital broadcasting standard, two banks of memory areas of the maximum number of slots × 8 × 2 slots can be prepared. I just need. In addition, for example, 8
The same applies when four types of TS are selected and four types of TS are selected.

(Embodiment 30) Embodiment 3 of the present invention
The error correction circuit at 0 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 67 is a diagram showing the “T” described in the fourteenth embodiment.
FIG. 9 is a block diagram illustrating a configuration example of an error correction circuit 3001 in a case where “with MCC” and “without TMCC”. This error correction circuit 3001 is different from the first embodiment shown in FIG.
In the fourth error correction circuit 1401, a channel selection circuit 1705 having a different internal configuration is provided, and the control signal generation circuit 1701 replaces the transmission control information decoding circuit 20010.
4 is provided. Other blocks, that is, de-interleave circuit 1402, de-randomize circuit 1407, Viterbi decoder 20002 to symbol / byte conversion circuit 20004, MPEG sync byte /
Dummy slot insertion circuit 20006, RS decoding circuit 2
Each function of the 0008 to speed conversion circuit 200009 is shown in FIG.
Are the same as those shown in FIG.

In the error correction circuit 3001 of this embodiment, the channel selection circuit 1705 generates a slot selection signal as in the case of the twenty-ninth embodiment, and
The signal is output to the interleave circuit 1402 and the de-randomizing circuit 1407 in FIG. The de-interleave circuit 1402 and the de-randomize circuit 1407 are shown in FIG.
The same operation as in the fourteenth embodiment is performed as shown in FIG.

[0438] The error correction capability of the error correction circuit 3001 described above is secured to the same degree as the error correction circuit of the fourteenth embodiment.

As in the fourteenth embodiment, for example, B
If the maximum number of slots per frame occupied by 1TS is determined in the S digital broadcasting standard, a memory area of 2 banks of (maximum number of slots × 8 slots) may be prepared. The memory area to be used is not limited to two banks of 24 × 8 slots as in the fourteenth embodiment.

Also, as in the fourteenth embodiment, for example, TS1: <high-layer image> TC-8PSK: 14 slots <low-layer image> QPSK (r = 1/2): 2 slots (of which, dummy 1 Slot) TS2: <high-layer image> TC-8PSK: 12 slots <low-layer image> QPSK (r = 3/4): 4 slots (of which, one dummy slot) TS3: <high-layer image> TC- 8PSK: 12 slots <Low-level image> BPSK (r = 1/2): 4 slots (of which, 3 slots are dummy) A case is considered in which three types of TS are input. That is, 3TS is assigned to one transponder. When one type of TS is selected, as in the fourteenth embodiment, only the selected one TS is written into the memory circuit 1406, the speed is converted, and read at a speed of 16/48 = 1/3. Should be performed. When two types of TSs are selected, for example, when one TS is displayed on a monitor and the other one is video-recorded, only the selected two TSs are stored in the memory circuit 14.
06 and read at a speed of 32/48 = ２. In this case, if the maximum number of slots per frame occupied by one TS is determined in the BS digital broadcasting standard, the maximum number of slots × 8 × 2
It is sufficient to prepare a memory area for two banks of slots. In addition, for example, eight types of TS are input, and four types of T
The same applies to the case where S is selected.

In the case of the present embodiment, the first embodiment
Similarly to FIG. 4, an enable signal as shown in FIG. 108 (e), that is, a signal in which the valid period of the MPEG packet of 188 bytes is “H” and the parity section of the 16-byte RS code is “L” is shown in FIG. What is necessary is just to generate | occur | produce in 67 tuning circuits 1705.

In this embodiment, the PN generation in the de-randomizing circuit 1407 is bit serial, but it may be an 8-bit parallel PN generation. In that case, the P / S conversion circuit 20030 and the S / P
The conversion circuit 20031 can be omitted.

(Embodiment 31) Embodiment 3 of the present invention
1 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 68 is a block diagram of “T” described in the fifteenth embodiment.
FIG. 14 is a block diagram illustrating a configuration example of an error correction circuit 3101 in the case of “without MCC” with respect to “with MCC”. This error correction circuit 3101 is similar to that of the first embodiment shown in FIG.
In the fifth error correction circuit 1501, a channel selection circuit 1705 having a different internal configuration is provided, and a control signal generation circuit 170
4 is provided. Other blocks, that is, the speed conversion circuit 1502 and the Viterbi decoder 2000
Each function of 2 to RS decoding circuit 20008 is the same as that shown in FIG.

In error correction circuit 3101 of the present embodiment, channel selection circuit 1705 generates a slot selection signal and outputs it to speed conversion circuit 1502 in FIG. 69, as in the case of the twenty-ninth embodiment. Speed conversion circuit 1502 performs the same operation as in the fifteenth embodiment.

The error correction capability of the error correction circuit 3101 described above is secured to the same degree as the error correction circuit of the fifteenth embodiment.

Note that, as in the fifteenth embodiment, for example, B
If the maximum number of slots per frame occupied by 1TS is determined in the S digital broadcasting standard, a memory area having the maximum number of slots may be prepared.
The memory area used by the memory circuit 1506 is not limited to 24 slots as in the fifteenth embodiment.

Also, as in the fifteenth embodiment, for example, TS1: <high-layer image> TC-8PSK: 14 slots <low-layer image> QPSK (r = １ ／): 2 slots (of which, dummy 1) Slot) TS2: <high-layer image> TC-8PSK: 12 slots <low-layer image> QPSK (r = 3/4): 4 slots (of which, one dummy slot) TS3: <high-layer image> TC- 8PSK: 12 slots <Low-level image> BPSK (r = 1/2): 4 slots (of which, 3 slots are dummy) A case is considered in which three types of TS are input. That is, 3TS is assigned to one transponder. When one kind of TS is selected, as in the fifteenth embodiment, only the selected one TS is written in the memory circuit 1506, the speed is converted, and the read is performed at a speed of 16/48 = 1/3. Should be performed. When two types of TSs are selected, for example, when one TS is displayed on a monitor and another one is video-recorded, only the selected two TSs are stored in the memory circuit 15.
06, speed conversion is performed, and 32/48 = 2/3
The reading may be performed at the speed described above. In this case, if the maximum number of slots per frame occupied by one TS is determined in the BS digital broadcasting standard, a memory area of the maximum number of slots × 2 slots may be prepared. In addition, for example, eight types of TS are input, and four types of T
The same applies to the case where S is selected.

As described in the fifteenth embodiment, the speed conversion circuit 1508 may be configured to convert the speed of a plurality of tuned TSs and output them continuously in parallel.

FIG. 70 shows the case where the error correction circuit 1507 for “with TMCC” shown in FIG.
FIG. 18 is a block diagram illustrating a configuration example of an error correction circuit 3102 having a parallel output function in the case of “no C”. This error correction circuit 3102 is different from the error correction circuit 1507 of the fifteenth embodiment shown in FIG. 43 in that a channel selection circuit 1705 having a different internal configuration is provided and that the transmission control information decoding circuit 2
A feature is that a control signal generation circuit 1704 is provided in place of 0010. The other blocks, that is, the functions of the speed conversion circuit 1508 and the Viterbi decoder 20002 to the RS decoding circuit 200008) are the same as those shown in FIG.

The speed conversion circuit 1508 includes the channel selection circuit 170
The operation similar to that of the fifteenth embodiment is performed as shown in FIG.

The error correction capability of the error correction circuit 3102 described above is secured to the same degree as the error correction circuit of the fifteenth embodiment.

It is to be noted that a configuration may be considered in which 16 bytes of the parity byte are not read / written from / to the memory circuit 1506 or the memory circuit 1512, and the speed is converted. In this case, the memory circuit 1506 or the memory circuit 1512
Can be reduced to 188/204 = 47/51,
The read address generation circuit 1505 or the read address generation circuit 1511 does not need to generate an enable signal. The 47/51 speed conversion can be easily realized by, for example, providing a counter circuit for outputting a ripple carry signal when the count value reaches 51, and inputting 47 to this counter circuit. In this case, the ripple carry signal is output at a speed of 47/51 of the input.

(Embodiment 32) Embodiment 3 of the present invention
2 will be described with reference to the drawings. In this embodiment, a case where the superframe structure is temporally constant without “TMCC” will be described.

FIG. 72 is a block diagram showing a configuration example of the error correction circuit 3201 in the case of "without TMCC", in contrast to the error correction circuit 1601 in the case of "with TMCC". This error correction circuit 3201 is different from the error correction circuit 1601 of the sixteenth embodiment shown in FIG. 45 in that a channel selection circuit 1705 having a different internal configuration is provided, and a control signal generation circuit is provided instead of the transmission control information decoding circuit 20010. A feature is that a circuit 1704 is provided. Other blocks, that is, a de-interleave circuit 1302, a speed conversion circuit 1602, a Viterbi decoder 20002-symbol /
Byte conversion circuit 20004, MPEG synchronous byte / dummy slot insertion circuit 20006 to RS decoding circuit 200
Each function 08 is the same as that shown in FIG.

In the error correction circuit 3201 according to the present embodiment, as described in the twenty-ninth embodiment, FIG.
The deinterleaved data shown in FIG.
Output from the interleave circuit 1302. The number of effective slots per frame in one TS is 24.

As shown in FIG. 35 (b), the byte data sequence output from the de-interleave circuit 1302 is composed of the MPEG sync byte / dummy
Slot insertion circuit 20006, de-randomizing circuit 2
[0007] The signal is processed by the RS decoding circuit 20008 and output to the speed conversion circuit 1602. Tuning circuit 1705 generates a slot selection signal and outputs it to speed conversion circuit 1602 in FIG. 73 in the same manner as in the twenty-ninth embodiment. Speed conversion circuit 1602 performs the same operation as in the sixteenth embodiment.

The error correction capability of the error correction circuit 3201 described above is secured to the same degree as the error correction circuit of the sixteenth embodiment.

Note that, as in the sixteenth embodiment, for example, B
If the maximum number of slots per frame occupied by 1TS is determined in the S digital broadcasting standard, a memory area having the maximum number of slots may be prepared.
The memory area used by the memory circuit 1606 is not limited to 24 slots as in the sixteenth embodiment.

Similarly to the sixteenth embodiment, for example, TS1: <high-layer image> TC-8PSK: 14 slots <low-layer image> QPSK (r = 1/2): 2 slots (of which, dummy 1) Slot) TS2: <high-layer image> TC-8PSK: 12 slots <low-layer image> QPSK (r = 3/4): 4 slots (of which, one dummy slot) TS3: <high-layer image> TC- 8PSK: 12 slots <Low-layer image> BPSK (r = 1/2): 4 slots (including 3 dummy slots) A case is assumed in which three types of TS are input. That is, 3TS is assigned to one transponder. When one kind of TS is selected, as in the sixteenth embodiment, only the selected one TS is written into the memory circuit 1606, the speed is converted, and the TS is read at a speed of 16/48 = 1/3. Should be performed. Further, when two types of TSs are selected, for example, when one TS is displayed on a monitor and another one is video-recorded, only the selected two TSs are stored in the memory circuit 16.
06, speed conversion is performed, and 32/48 = 2/3
The reading may be performed at the speed described above. In this case, if the maximum number of slots per frame occupied by one TS is determined in the BS digital broadcasting standard, a memory area of the maximum number of slots × 2 slots may be prepared. In addition, for example, eight types of TS are input, and four types of T
The same applies to the case where S is selected.

[0461] As described in the sixteenth embodiment, the speed conversion circuit 1608 may be configured to convert the speed of a plurality of tuned TSs and output them continuously in parallel.

FIG. 74 is a block diagram showing a configuration example of an error correction circuit 3202 having a function of parallel output in the case of "without TMCC", in contrast to the error correction circuit 1607 in the case of "with TMCC". This error correction circuit 3202
Is the error correction circuit 160 of the sixteenth embodiment shown in FIG.
7 is characterized in that a channel selection circuit 1705 having a different internal configuration is provided and a control signal generation circuit 1704 is provided in place of the transmission control information decoding circuit 20010. Other blocks, that is, a de-interleave circuit 1302, a speed conversion circuit 1608, a Viterbi decoder 20002 to a symbol / byte conversion circuit 20004, M
PEG sync byte / dummy slot insertion circuit 2000
Each function of the 6-RS decoding circuit 20008 is the same as that shown in FIG.

The speed conversion circuit 1608 performs the same operation as in the sixteenth embodiment by using the slot selection signal output from the channel selection circuit 1705 as shown in FIG.

[0464] The error correction capability of the error correction circuit 3202 described above is secured to the same degree as that of the error correction circuit of the sixteenth embodiment.

As in the sixteenth embodiment, a configuration is conceivable in which a 16-byte parity byte is subjected to speed conversion without reading from or writing to the memory circuit 1606 or the memory circuit 1612. In this case, the memory circuit 1606
Alternatively, the used area of the memory circuit 1612 is 188/204 =
47/51, and the read address generation circuit 16
05 or the read address generation circuit 1611 does not need to generate an enable signal. The 47/51 speed conversion can be easily realized by, for example, providing a counter circuit for outputting a ripple carry signal when the count value reaches 51, and inputting 47 to this counter circuit. In this case, the ripple carry signal is output at a speed of 47/51 of the input.

In the first embodiment, the error correction circuit 101 complies with the standard system of BS digital broadcasting currently under discussion, and the error correction coding apparatus 10001 of FIG.
Viterbi decoding is performed on the data sequence encoded in step (a), the influence of the transmission mode B after the transmission mode switching is completely cut off, and the transmission mode A before transmission mode switching remaining in the path memory 20021 when the transmission mode is switched. It is configured to output Viterbi decoded data.

However, a transmission frame is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and information about the modulation scheme and coding rate of each symbol is included as transmission control information for each frame. Performs Viterbi decoding of a data sequence that has been convolutionally encoded and transmitted by one convolutional encoder continuously over different modulation schemes and coding rates, using a configuration similar to that of the first embodiment. It is clear that the influence of the transmission mode B after the transmission mode switching can be completely cut off, and the Viterbi decoded data of the transmission mode A before the transmission mode switching remaining in the path memory 20021 can be output at the time of the transmission mode switching.

In Embodiments 2 to 12,
Error correction circuits 201, 301, 401, 501, 60
1, 701, 801, 901, 1001, 1101 and 1201 Viterbi-decode the data sequence encoded by the error correction encoding apparatus 10001 in FIG. . Then, by utilizing the property of the fixed symbol sequence of the TAB signal added before and after the TMCC, the influence of the transmission mode before and after the transmission mode switching of the TMCC is completely cut off, and the path memory 20021 when the transmission mode is switched. And outputs the TMCC Viterbi decoded data remaining in the.

However, the transmission frame is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and when the modulation scheme and the coding rate are switched, a fixed symbol sequence for termination follows the last symbol before switching. And information about the modulation scheme and coding rate of each symbol is included as transmission control information for each frame, and the symbols of each frame exceed different modulation schemes and coding rates,
The data sequence that is convolutionally coded and transmitted by one convolutional encoder continuously is transmitted according to the second to first embodiments.
Viterbi decoding is performed using the same configuration as that of 2. Then, by utilizing the property of the fixed symbol sequence, the influence of the transmission mode B after the transmission mode switching is completely cut off, and the transmission mode A before the transmission mode switching remaining in the path memory 200221 at the time of the transmission mode switching is removed. Obviously, Viterbi decoded data can be output.

Also, in the thirteenth embodiment, the error correction circuit 1301 complies with the standard system of BS digital broadcasting currently under discussion, and the error correction coding apparatus 100 shown in FIG.
01 is deinterleaved, and only the selected TS is read / written to / from the memory circuit 1306 to reduce the memory area to be used.

[0471] However, in a transmission system in which a plurality of MPEG transport streams are transmitted in a multiplexed transmission format, a data sequence of each packet of the MPEG transport stream is defined as a slot,
When 1 frame = M slots and 1 superframe = N frames, the transport stream number information of each slot is included in the superframe as transmission control information, and the superframe has a depth of N per slot. A data sequence to be transmitted after interleaving for M slots is de-interleaved by the same configuration as in the thirteenth embodiment, and only the selected TS is read / written to / from the memory circuit 1306 to use a memory area to be used. It is clear that can be reduced.

In the fourteenth embodiment, the error correction circuit 1401 complies with the standard system of BS digital broadcasting currently under discussion, and uses the error correction coding apparatus 100 shown in FIG.
01, the encoded data sequence is deinterleaved, and only the selected TS is speed-converted and output.

[0473] However, in a transmission system in which transmission is performed in a transmission format in which a plurality of MPEG transport streams are multiplexed, a data sequence of each packet unit of the MPEG transport stream is defined as a slot,
When 1 frame = M slots and 1 superframe = N frames, the transport stream number information of each slot is included in the superframe as transmission control information, and the superframe has a depth of N per slot. It is apparent that the data sequence transmitted after performing the interleaving for M slots can be deinterleaved by the same configuration as in the fourteenth embodiment, and that only the selected TS can be speed-converted and output.

In the fourteenth embodiment, the error correction circuit 1401 conforms to the standard system of BS digital broadcasting currently under discussion, and the error correction coding apparatus 100 shown in FIG.
01 is de-interleaved, and only the selected TS is speed-converted and output as the data sequence of the second byte of all 48 × 8 slots (one superframe). An initial value generating circuit 1409 capable of generating an initial value is provided to perform de-randomization.

[0475] However, in the transmission system in which a plurality of MPEG transport streams are transmitted in a multiplexed transmission format, a data sequence of each packet unit of the MPEG transport stream is defined as a slot,
When 1 frame = M slots and 1 superframe = N frames, transport stream number information of each slot is included as transmission control information in the superframe, and randomization is continuously performed in superframe units. It is clear that the data sequence to be transmitted can be de-randomized by the same configuration as in the fourteenth embodiment.

In the fifteenth embodiment, the error correction circuit 1501 and the error correction circuit 1507 are coded by the error correction coding apparatus 10001 of FIG. The speed of the data sequence is converted, and only the selected TS is read / written to / from the memory circuit 1506 or the memory circuit 1512, so that the memory area to be used is reduced.

However, in a transmission system in which a plurality of MPEG transport streams are transmitted in a multiplexed transmission format, a data sequence in each packet unit of the MPEG transport stream is defined as a slot,
When 1 frame = M slots and 1 superframe = N frames, a data sequence transmitted by including transport stream number information of each slot as transmission control information in a superframe is described in the first embodiment.
It is apparent that the memory area to be used can be reduced by performing speed conversion with the same configuration as in No. 5 and reading and writing only the selected TS in the memory circuit 1506 or the memory circuit 1512.

In the sixteenth embodiment, the error correction circuit 1601 and the error correction circuit 1607 are coded by the error correction coding apparatus 10001 in FIG. The deinterleaved data sequence is output from the deinterleave circuit 1302, and only the selected TS is output. The speed conversion circuit 1602 or the speed conversion circuit 1608 converts the speed of the data sequence and stores only the selected TS in the memory. Circuit 16
06 or the memory circuit 1612 to reduce the memory area used.

[0479] However, in a transmission system in which a plurality of MPEG transport streams are transmitted in a multiplexed transmission format, a data sequence of each packet unit of the MPEG transport stream is defined as a slot,
When 1 frame = M slots and 1 superframe = N frames, the transport stream number information of each slot is included in the superframe as transmission control information, and the superframe has a depth of N per slot. The data sequence transmitted after interleaving for M slots is de-interleaved by the same configuration as in the sixteenth embodiment, and only the selected TS is output from de-interleave circuit 1302, and speed conversion circuit 1602 Alternatively, the speed conversion circuit 1608 converts the speed of the data sequence, and stores only the selected TS in the memory circuit 16.
Obviously, by reading and writing to or from the memory circuit 1612 or the memory circuit 1612, the memory area used can be reduced.

Also, in the seventeenth embodiment, the error correction circuit 1703 uses the “No TMCC”, that is, the error correction circuit 1703 shown in FIG. In the correction coding device 1701, the data sequence coded as shown in FIG. 53 is Viterbi-decoded, and the influence of the transmission mode B after the transmission mode switching is completely cut off, and remains in the path memory 20021 when the transmission mode is switched. Of the transmission mode A before switching the transmission mode.

However, the data sequence on the transmitting side is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and each symbol exceeds one of the different modulation schemes and coding rates, and is successively subjected to one convolutional coding. The data sequence convoluted and coded by the transmitter is transmitted in the first embodiment.
7, the effect of the transmission mode B after the transmission mode switching is completely cut off, and the Viterbi decoding of the transmission mode A before the transmission mode switching remaining in the path memory 200221 at the time of the transmission mode switching. Obviously, the data can be output.

In the eighteenth to eighteenth embodiments, the error correction circuits 1801, 1901, 2001, and 21
01, 2201, 301, 2401, 2501, 26
In the standard system of BS digital broadcasting currently under discussion, reference numerals 01, 2701, and 801 denote “no TMCC”, that is, the error correction encoding device 1701 of FIG. 49 in which the superframe structure is temporally constant as shown in FIG. Viterbi decoding of the encoded data sequence, and utilizing the characteristics of the fixed symbol sequence of the TAB signal added before and after the character multiplexed data, the effect of the transmission mode before and after switching the transmission mode of the character multiplexed data Is completely shut off, and Viterbi decoded data of the character multiplexed data remaining in the path memory 20021 is output when the transmission mode is switched.

However, the data sequence on the transmitting side is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and at the time of switching between the modulation schemes and the coding rates, it is terminated after the last symbol before switching. There is a case where a fixed symbol sequence is included, and each symbol exceeds a different modulation scheme and coding rate, and a data sequence transmitted by being convolutionally coded by one convolutional coder continuously is transmitted as described above. Viterbi decoding is performed using the same configuration as in Embodiments 18 to 28,
By utilizing the property of the fixed symbol sequence, the influence of the transmission mode B after the transmission mode switching is completely cut off, and the Viterbi decoding of the transmission mode A before the transmission mode switching remaining in the path memory 20021 at the time of the transmission mode switching. Obviously, the data can be output.

In the twenty-ninth embodiment, the error correction circuit 2901 uses the “no TMCC”, that is, the error correction circuit 2901 shown in FIG. In the correction encoding device 1701, the encoded data sequence is de-interleaved as shown in FIG. 97, and only the selected slot is read / written to / from the memory circuit 1306 to reduce the memory area to be used. .

[0485] However, in the transmission format, when the fixed-length data sequence of the minimum unit is a slot, and one frame is M slots and one superframe is N frames, the interleaving of the depth N is performed in units of slot in the superframe. A data sequence transmitted for M slots is de-interleaved by the same configuration as in the twenty-ninth embodiment, and only the selected slot is read / written to / from the memory circuit 1306, so that the memory area to be used can be reduced. Is clear.

Also, in the above-mentioned thirty-fifth embodiment, the error correction circuit 3001 uses the error correction circuit 3001 shown in FIG. The correction coding device 1701 is configured to de-interleave the coded data sequence as shown in FIG. 97, and to speed-convert only the selected slot to output.

However, in the transmission format, when the fixed-length data sequence of the minimum unit is a slot, and one frame is M slots and one superframe is N frames, the interleaving of depth N is performed in units of slot in the superframe. It is apparent that the data sequence transmitted for M slots is de-interleaved by the same configuration as in Embodiment 30 and that only the selected slot can be speed-converted and output.

Also, in the above-mentioned Embodiment 30, the error correction circuit 3001 uses “No TMCC”, that is, the error correction circuit 3001 shown in FIG. In the correction encoding device 1701, the data sequence encoded as shown in FIG. 97 is de-interleaved, and the data sequence output by subjecting only the selected slot to speed conversion is converted to 4
An initial value generating circuit 1409 capable of generating an initial value of the second byte for all 8 × 8 slots (one superframe) is provided to perform de-randomization.

However, in the transmission format, when the fixed-length data sequence of the minimum unit is a slot, and one frame is M slots and one superframe is N frames, randomization is continuously performed and transmitted in superframe units. It is clear that the data series can be de-randomized by a configuration similar to that of the thirtieth embodiment.

[0490] Also, in the above-mentioned Embodiment 31, the error correction circuit 3101 and the error correction circuit 3102 use the "TMC
In the error correction coding apparatus 1701 shown in FIG. 49 in which no C is set, that is, the superframe structure is temporally constant, the data sequence coded as shown in FIG. 97 is rate-converted, and only the selected slot is stored in the memory. By reading from and writing to the circuit 1506 or the memory circuit 1512, a memory area to be used is reduced.

However, in the transmission format, when the fixed-length data sequence of the minimum unit is a slot, and one frame is M slots and one superframe is N frames, the transmitted data sequence is the same as in the thirty-first embodiment. Depending on the configuration, the speed is converted and only the selected slot is stored in the memory circuit 1506 or the memory circuit 1512.
It is clear that the memory area used can be reduced by reading and writing the data.

[0492] Also, in the above-mentioned Embodiment 32, in the standard system of BS digital broadcasting currently under discussion, "TM
No CC ”, that is, in the error correction coding device 1701 of FIG. 49 in which the superframe structure is temporally constant,
As shown in FIG. 97, the encoded data sequence is deinterleaved, and only the selected slot is output from the deinterleave circuit 1302, and the speed conversion circuit 1602 or the speed conversion circuit 1608 performs the speed conversion on the data sequence, By reading and writing only the selected slot in the memory circuit 1606 or the memory circuit 1612, the memory area to be used is reduced.

However, in the transmission format, when the fixed-length data sequence of the minimum unit is a slot, and one frame is M slots and one superframe is N frames, the interleaving of the depth N is performed in units of slot in the superframe. A data sequence transmitted for M slots is de-interleaved by the same configuration as in the above-mentioned thirty-second embodiment, and only the selected slot is output from de-interleave circuit 1302, and speed conversion circuit 1602 or speed conversion It is apparent that the memory area used can be reduced by the circuit 1608 speed-converting the data sequence and reading / writing only the selected slot in the memory circuit 1606 or the memory circuit 1612.

In the first embodiment, for the last symbol in transmission mode A before switching the transmission mode, only one state having the minimum path metric in the trellis diagram is valid.

Instead, the ACS circuit 105 shown in FIG.
However, the configuration may be such that the value of the path metric memory 20020 is reset using the switching control signal output from the Viterbi decoder control circuit 103. That is, as shown in the trellis diagram of FIG. 119, the transmission mode A before the transmission mode switching is performed.
For the last symbol in the trellis diagram, the one-state path metric (Path M
etric: PM) only, the smallest possible value, eg "
The state is reset to 0 ". Other states are reset to the maximum possible values. With this configuration, the influence of the transmission mode B after mode switching is cut off and remains in the path memory 20021 at the time of transmission mode switching. Transmission mode A before mode switching
Can be output. According to this configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

In the second embodiment, the ACS circuit 205 shown in FIG. 6 uses the confirmed state signal output from the Viterbi decoder control circuit 203 to validate only one confirmed state and to change the other states. The configuration is such that the path metric memory 20082 and the path memory 20021 are controlled so that all are invalidated.

Instead, the ACS circuit 205 shown in FIG.
, The path metric memory 200
The value of 20 may be reset. That is, FIG.
As shown in the trellis diagram of 0, only the determined one-state path metric is set to the minimum possible value, for example, “0”. Then, the other states are reset to the maximum possible values. With this configuration, the influence of the transmission mode B after the mode switching is cut off, and the path memory 200 is switched when the transmission mode is switched.
21 before the mode switching (BPS
K: r = １ ／) can be output. According to this configuration, the path metric memory 20
Since the value of 020 is simply reset, there is an advantage that control is simplified.

Also, in the above configuration, FIG.
As shown in FIG. 6A, the Viterbi decoder control circuit 20 shown in FIG.
3 is the tenth symbol (S) of each TAB signal (w1, w2, w3) from the time when the first symbol of 20 symbols (10 symbols after S / P conversion) is input to the path memory 20021. It is not necessary to limit to a configuration in which the final state signal is generated until the / P-converted final symbol is input to the path memory 20021 and output to the ACS circuit 205. As shown in FIGS. 120 (a) to 120 (c), the period for generating the confirmed state signal is one symbol or more,
Up to ten symbols can be arbitrarily selected, and which symbol is selected is also arbitrary.

The effect of improving the BER by the above configuration was examined by simulation. FIG. 121 is a configuration diagram of a transmission frame used for the simulation. Fig. 121
(A) is a signal arrangement diagram at the time of input to the Viterbi decoder 202 (TMCC is before S / P conversion), and FIG. 121 (b)
14 is a signal arrangement diagram at the time of input to the path memory 20021 (TMCC after S / P conversion). The path memory length is 64, and the main signal after TMCC is TC-8PSK (r = 2
/ 3) Only 64 symbols were used. Immediately before the first symbol of the TMCC is input by the main signal of 64 symbols, the path memory 20021 stores the TC-8PSK (r = 2
/ 3) The state is satisfied with 64 symbols.

FIG. 122 shows the results of the above simulation under the condition that C / N = -2 dB. Path memory 2
At the time when the last symbol of the rear TAB signal (w2 or w3) is input to the path memory 20021,
The BER for each symbol was calculated for the 64 symbols remaining in. The horizontal axis shows 64 symbols remaining in the path memory 20021, and the vertical axis shows the value of BER. FIG. 122 shows a case where the value of the path metric memory 20020 is reset with the first symbol or the last symbol of the subsequent TAB signal (w2 or w3).

As is clear from FIG. 122, the "with termination processing" of the present embodiment has a higher error rate of each symbol remaining in the path memory 20021 than the "without termination processing" of the conventional example. It can be seen that it has been improved. In addition, the path metric memory 20 stores the first symbol of the rear TAB signal.
Resetting the value of 020 is more effective than resetting with the last symbol because the BER of the net TMCC data indicated by the 0th to 47th symbols in FIG. 122 is reduced.

Also, in Embodiment 4 described above, FIG.
The ACS circuit 405 uses the state reduction signal output from the Viterbi decoder control circuit 403, and for each of the first six symbols (after S / P conversion) of each TAB signal, for each symbol (after S / P conversion). The number of states has been halved. For the subsequent 10 symbols (after S / P conversion), the determined 1
In order to make only the state valid, the path metric memory 2
0020 and the path memory 20021 are controlled.

[0503] Instead, the ACS circuit 405 of FIG.
Is a path metric memory 200 using a state reduction signal.
The value of 20 may be reset. That is, each T
For the first 6 symbols of the AB signal (after S / P conversion),
32, 1 for each symbol (after S / P conversion)
Only the path metrics in the 6, 8, 4, 2, 1 states are set to the minimum possible value, for example, "0", and the other states are reset to the maximum possible value. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the Viterbi decoded data of the TMCC (BPSK: r = １ ／) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching. Can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

In the sixth embodiment, FIG.
As in the second embodiment shown in (a) to (c), the ACS circuit 605 in FIG. 20 uses the confirmed state signal output from the Viterbi decoder control circuit 603 to validate only one confirmed state, The path metric memory 20080 and the path memory 20021 are controlled so that all other states are invalidated.

Instead, the ACS circuit 605 of FIG.
Uses the determined state signal to store the path metric memory 2002
A configuration in which the value of 0 is reset may be adopted. That is, only the determined one-state path metric is the minimum possible value,
For example, it is set to "0", and the other states are reset to the maximum possible values. With this configuration, the influence of the transmission mode B after the mode switching is cut off, and the TMC before the mode switching remaining in the path memory 20021 when the transmission mode is switched.
C (BPSK: r = 1/2) Viterbi decoded data can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

Also, in Embodiment 8 described above, FIG.
24, the ACS circuit 805 of FIG. 24 uses the confirmed state signal output from the Viterbi decoder control circuit 803 to validate only one confirmed state. , The path metric memory 20080 and the path memory 20021 are controlled so that all other states are invalidated. Also, as in the fourth embodiment shown in FIG. 13, the ACS circuit 805 includes a Viterbi decoder control circuit 803.
The path metric memory 20080 and the path memory 20021 are controlled for the first six symbols (after S / P conversion) of each TAB signal using the state reduction signal output from. Then, the number of states is reduced by half until the convolution circuit 10014 is determined to be in one state.

Instead, the ACS circuit 805 of FIG.
, The path metric memory 200
The value of 20 may be reset. That is, only the determined path metric of one state is set to the minimum possible value, for example, “0”, and the other states are reset to the maximum possible value. Further, the ACS circuit 805 may be configured to reset the value of the path metric memory 20020 using the state reduction signal. That is, for the first six symbols (after S / P conversion) of each TAB signal, the determined 32, 16, 8, 4,.
Only the path metrics in the 2 and 1 states are set to the minimum possible value, for example, "0", and the other states are reset to the maximum possible value. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the T before the mode switching remaining in the path memory 20021 when the transmission mode is switched.
MCC (BPSK: r = 1/2) Viterbi decoded data can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

Also, in the above-mentioned Embodiment 8, FIG.
As shown in FIG. 7A, the Viterbi decoder control circuit 803 stores the first symbol of 20 symbols (10 symbols after S / P conversion) of each TAB signal (w1, w2, w3) in the path memory 20021. From the point of input to the path memory 20021 until the tenth symbol (the last symbol after S / P conversion) of each TAB signal is input to the path memory 20021, and outputs the signal to the ACS circuit 805. did.

Instead, the ACS circuit 805 of FIG.
However, the configuration may be such that the value of the path metric memory 20080 is reset using the final state signal output from the Viterbi decoder control circuit 803. That is, as shown in FIG. 120, only the determined one-state path metric is set to the minimum possible value, for example, “0”, and the other states are reset to the maximum possible value. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the Viterbi decoded data of the TMCC (BPSK: r = １ ／) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching. Can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

In Embodiment 9 described above, FIG.
The ACS circuit 905 uses the state reduction signal output from the Viterbi decoder control circuit 903 in the same manner as in the fourth embodiment shown in FIG. 13 to start 6 symbols of each TAB signal (after S / P conversion). For the path metric memory 2
0020 and the path memory 20021 were controlled.
Then, the number of states is reduced by half until the convolution circuit 10014 is determined to be in one state.

[0511] Instead, the ACS circuit 905 of FIG.
Uses the state reduction signal to generate a path metric memory 2002.
A configuration in which the value of 0 is reset may be adopted. That is, each TA
For the first six symbols of the B signal (after S / P conversion), 1
For each symbol (after S / P conversion), 32, 16,
Only the path metrics in the 8, 4, 2, and 1 states are set to the minimum possible value, for example, "0", and the other states are reset to the maximum possible value. With this configuration, the influence of the transmission mode B after the mode switching is cut off, and the Viterbi decoded data of the TMCC (BPSK: r = 1/2) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching. Can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

[0512] In Embodiment 10 described above, FIG.
8 ACS circuit 1005 is the same as that of the fourth embodiment shown in FIG.
In the same manner as described above, the path metric memory 20080 and the path memory 20021 are controlled for the first six symbols (after S / P conversion) of each TAB signal using the state reduction signal output from the Viterbi decoder control circuit 1003. I was going. Then, the number of states is reduced by half until the convolution circuit 10014 is determined to be in one state.

Instead, the ACS circuit 100 shown in FIG.
5 is a path metric memory 20 using the state reduction signal.
The value of 020 may be reset. That is, for the first six symbols (after S / P conversion) of each TAB signal, the determined 32 for each symbol (after S / P conversion),
Only the path metrics of the states 16, 8, 4, 2, and 1 are set to the minimum possible values, for example, "0", and the other states are reset to the maximum possible values. With such a configuration,
The Viterbi decoded data of TMCC (BPSK: r =＝) before mode switching remaining in the path memory 20021 can be output when the transmission mode is switched, by blocking the effect of the transmission mode B after the mode switching. . According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

[0514] In the eleventh embodiment, FIG.
0 of the Viterbi decoder control circuit 11 in the same manner as in the second embodiment shown in FIGS.
03 using the determined state signal output from
The path metric memory 20020 and the path memory 20 are configured so that only the state is valid and all other states are invalid.
021 was performed. Also, the ACS circuit 1105
Is the first six symbols of each TAB signal (after S / P conversion) using the state reduction signal output from Viterbi decoder control circuit 1103 in the same manner as in Embodiment 4 shown in FIG.
With regard to, the path metric memory 20080 and the path memory 20021 are controlled. Then, the number of states is reduced by half until the convolution circuit 10014 is determined to be in one state.

Instead, the ACS circuit 110 shown in FIG.
5 is a path metric memory 20 using the determined state signal.
The value of 020 may be reset. That is, only the determined path metric of one state is set to the minimum possible value, for example, “0”, and the other states are reset to the maximum possible value. Further, the ACS circuit 1105 may be configured to reset the value of the path metric memory 20020 using the state reduction signal. That is, for the first six symbols (after S / P conversion) of each TAB signal, the determined 32, 16, 8, 4,.
Only the path metrics in the 2 and 1 states are set to the minimum possible value, for example, "0", and the other states are reset to the maximum possible value. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the T before the mode switching remaining in the path memory 20021 when the transmission mode is switched.
MCC (BPSK: r = 1/2) Viterbi decoded data can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

[0516] In the eleventh embodiment, FIG.
As shown in FIG. 7 (a), the Viterbi decoder control circuit 1103 of FIG. 0 transmits the first symbol of each of the 20 symbols (10 symbols after S / P conversion) of each TAB signal (w1, w2, w3) From the time when the data is input to the memory 20021, each T
Until the tenth symbol of the AB signal (the last symbol after S / P conversion) is input to the path memory 20021, a determined state signal is generated and output to the ACS circuit 205.

Instead, the ACS circuit 110 shown in FIG.
5 may be configured to reset the value of the path metric memory 20082 using the determinate state signal output from the Viterbi decoder control circuit 1103. That is, as shown in FIG. 120, only the determined one-state path metric is set to the minimum possible value, for example, “0”, and the other states are reset to the maximum possible value. With such a configuration,
The Viterbi decoded data of TMCC (BPSK: r =＝) before mode switching remaining in the path memory 20021 can be output when the transmission mode is switched, by blocking the effect of the transmission mode B after the mode switching. . According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

In the twelfth embodiment, FIG.
2 ACS circuit 1205 corresponds to the fourth embodiment shown in FIG.
Similarly to the above, the path metric memory 20080 and the path memory 20021 are controlled for the first six symbols (after S / P conversion) of each TAB signal using the state reduction signal output from the Viterbi decoder control circuit 1203. I was going. Then, the number of states is reduced by half until the convolution circuit 10014 is determined to be one state.

Instead, the ACS circuit 120 shown in FIG.
5 is a path metric memory 20 using the state reduction signal.
The value of 020 may be reset. That is, for the first six symbols (after S / P conversion) of each TAB signal, the determined 32 for each symbol (after S / P conversion),
Only the path metrics of the states 16, 8, 4, 2, and 1 are set to the minimum possible values, for example, "0", and the other states are reset to the maximum possible values. With such a configuration,
The Viterbi decoded data of TMCC (BPSK: r =＝) before mode switching remaining in the path memory 20021 can be output when the transmission mode is switched, by blocking the effect of the transmission mode B after the mode switching. . According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

[0520] In Embodiment 17, the last symbol of transmission mode A before switching the transmission mode is as follows.
Only one state having the minimum path metric was valid in the trellis diagram.

[0521] Instead, the ACS circuit 105 of FIG.
However, the configuration may be such that the value of the path metric memory 20020 is reset using the switching control signal output from the Viterbi decoder control circuit 103. That is, as shown in FIG. 119, for the last symbol of the transmission mode A before the transmission mode switching, only the one-state path metric having the minimum path metric in the trellis diagram is set to the minimum possible value, for example, “0”. Reset other states to the maximum possible value. With such a configuration, the influence of the transmission mode B after the mode switching can be cut off, and the Viterbi decoded data of the transmission mode A before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching can be output. According to such a configuration, the path metric memory 2
Since the value of 0020 is simply reset, there is an advantage that control is simplified.

In the eighteenth embodiment, FIG.
Of the path metric memory 20082 and the path memory 200 so that only the determined one state is made valid and all other states are made invalid using the confirmed state signal output from the Viterbi decoder control circuit 203. It was configured to perform the control of 20021.

[0523] Instead, the ACS circuit 205 may be configured to reset the value of the path metric memory 20020 by using the determined state signal output from the Viterbi decoder control circuit 203. That is, as shown in FIG. 120, only the determined one-state path metric is set to the minimum possible value, for example, “0”, and the other states are reset to the maximum possible value. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the Viterbi of the character multiplexed data (BPSK: r = １ ／) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching is removed. Decoded data can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

[0524] Also in the above-described configuration, the Viterbi decoder control circuit 203 of FIG. 6 performs, as shown in FIG. 120 (a), 20 symbols of each TAB signal (w1, w2, w3) (after S / P conversion). Is 10 symbols),
From the point in time when the data is input to the path memory 20021, each TAB
10th symbol of signal (final symbol after S / P conversion)
May be configured to generate a confirmed state signal until the moment when is input to the path memory 20021 and output it to the ACS circuit 205. As shown in FIGS. 120 (a) to 120 (c), the period during which the confirmed state signal is generated can be arbitrarily selected from one symbol or more and up to 10 symbols, and which symbol is selected as desired. is there.

In the twentieth embodiment, FIG.
2 ACS circuit 405 is a Viterbi decoder control circuit 403
, The number of states (after S / P conversion) for each of the first six symbols (after S / P conversion) of each TAB signal is reduced by half, and
For the symbol (after S / P conversion), the path metric memory 200 is set so that only one determined state is valid.
20 and the path memory 20021 are controlled.

[0526] Instead, the ACS circuit 405 may be configured to reset the value of the path metric memory 20020 using the state reduction signal. That is, for the first six symbols (after S / P conversion) of each TAB signal, the determined 32, 16, 8,
Only the path metrics of the 4, 2, and 1 states are set to the minimum possible values, for example, "0", and the other states are reset to the maximum possible values. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the Viterbi of the character multiplexed data (BPSK: r = １ ／) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching is removed. Decoded data can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

In Embodiment 22 described above, the ACS circuit 605 of FIG. 20 is similar to the embodiment 2 shown in FIGS. 7A to 7C in that the ACS circuit 605 of FIG.
By using the final state signal output from 3 so that only one final state is valid and all other states are invalid,
Path metric memory 2002 and path memory 2002
1 was performed.

[0528] Instead, the ACS circuit 605 may be configured to reset the value of the path metric memory 20020 using the confirmed state signal. That is, only the determined path metric of one state is set to the minimum possible value, for example, “0”, and the other states are reset to the maximum possible value. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the Viterbi of the character multiplexed data (BPSK: r = １ ／) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching is removed. Decoded data can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

In Embodiment 24 described above, FIG.
The ACS circuit 805 of the fourth embodiment is similar to the second embodiment shown in FIGS.
The path metric memory 20082 and the path memory 20021 use the confirmed state signal output from the controller so that only one confirmed state is valid and all other states are invalid.
Was controlled. In addition, the ACS circuit 805 is provided in FIG.
In the same manner as in the fourth embodiment shown in FIG. 19, each TA is used by using the state reduction signal output from the Viterbi decoder control circuit 803.
For the first six symbols of the B signal (after S / P conversion),
Path metric memory 2002 and path memory 2002
1 was performed. And the convolution circuit 100
Until 14 is determined to be one state, the number of states is reduced by half.

[0531] Instead, the ACS circuit 805 may be configured to reset the value of the path metric memory 20020 using the confirmed state signal. That is, only the determined path metric of one state is set to the minimum possible value, for example, “0”, and the other states are reset to the maximum possible value. Further, the ACS circuit 805 may be configured to reset the value of the path metric memory 20020 using the state reduction signal. That is, for the first six symbols of each TAB signal (after S / P conversion), (S / P
After the P conversion), only the determined path metrics of the determined 32, 16, 8, 4, 2, 1 states are the minimum possible values, for example, "
0 "to reset the other states to the maximum possible value. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the path memory 2 is switched when the transmission mode is switched.
It is possible to output Viterbi decoded data of the character multiplexed data (BPSK: r = 1/2) before the mode switching remaining in the 0021. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

[0531] In the twenty-fourth embodiment, FIG.
As shown in FIG. 7A, the Viterbi decoder control circuit 803 of FIG. 4 transmits the first symbol of each of the 20 symbols (10 symbols after S / P conversion) of each TAB signal (w1, w2, w3) From the time when the data is input to the memory 20021, each T
Until the tenth symbol of the AB signal (the last symbol after S / P conversion) is input to the path memory 20021, a determined state signal is generated and output to the ACS circuit 205.

[0532] Alternatively, the ACS circuit 805 may be configured to reset the value of the path metric memory 20020 by using the determinate state signal output from the Viterbi decoder control circuit 803. That is, as shown in FIG. 120, only the determined one-state path metric is set to the minimum possible value, for example, “0”, and the other states are reset to the maximum possible value. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the T before the mode switching remaining in the path memory 20021 when the transmission mode is switched.
MCC (BPSK: r = 1/2) Viterbi decoded data can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

In Embodiment 25 described above, FIG.
The ACS circuit 905 of No. 6 uses the state reduction signal output from the Viterbi decoder control circuit 903 in the same manner as in the fourth embodiment shown in FIG. Regarding ()), the path metric memory 20082 and the path memory 20021 are controlled. Then, the number of states is reduced by half until the convolution circuit 10014 is determined to be in one state.

Alternatively, the ACS circuit 905 may be configured to reset the value of the path metric memory 20020 using the state reduction signal. That is, for the first six symbols (after S / P conversion) of each TAB signal, the determined 32, 16, 8,
Only the path metrics of the 4, 2, and 1 states are set to the minimum possible values, for example, "0", and the other states are reset to the maximum possible values. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the Viterbi of the character multiplexed data (BPSK: r = １ ／) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching is removed. Decoded data can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

In the twenty-sixth embodiment, FIG.
8 ACS circuit 1005 is the same as that of the fourth embodiment shown in FIG.
In the same manner as described above, the path metric memory 20080 and the path memory 20021 are controlled for the first six symbols (after S / P conversion) of each TAB signal using the state reduction signal output from the Viterbi decoder control circuit 1003. I was going. Then, the number of states is reduced by half until the convolution circuit 10014 is determined to be in one state.

Alternatively, the ACS circuit 1005 may be configured to reset the value of the path metric memory 20020 using the state reduction signal. That is, for the first six symbols (after S / P conversion) of each TAB signal, the determined 32, 16, 8,
Only the path metrics of the 4, 2, and 1 states are set to the minimum possible values, for example, "0", and the other states are reset to the maximum possible values. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the Viterbi of the character multiplexed data (BPSK: r = １ ／) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching is removed. Decoded data can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

In the twenty-seventh embodiment, FIG.
0 of the Viterbi decoder control circuit 11 in the same manner as in the second embodiment shown in FIGS.
03 using the determined state signal output from
The path metric memory 20020 and the path memory 20 are configured so that only the state is valid and all other states are invalid.
021 was performed. Also, the ACS circuit 1105
Is the first six symbols of each TAB signal (after S / P conversion) using the state reduction signal output from Viterbi decoder control circuit 1103 in the same manner as in Embodiment 4 shown in FIG.
With regard to, the path metric memory 20080 and the path memory 20021 are controlled. Then, the number of states is reduced by half until the convolution circuit 10014 is determined to be in one state.

[0538] Instead, the ACS circuit 1105 may be configured to reset the value of the path metric memory 20020 using the confirmed state signal. That is, the determined 1
Only the path metric of the state is set to the minimum possible value, for example, “0”, and the other states are reset to the maximum possible value. Further, the ACS circuit 1105 may be configured to reset the value of the path metric memory 20020 using the state reduction signal. That is, for the first six symbols of each TAB signal (after S / P conversion), (S / P
After the P conversion), only the determined path metrics of the determined 32, 16, 8, 4, 2, 1 states are the minimum possible values, for example, "
0 "to reset the other states to the maximum possible value. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the path memory 2 is switched when the transmission mode is switched.
It is possible to output Viterbi decoded data of the character multiplexed data (BPSK: r = 1/2) before the mode switching remaining in the 0021. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

In the twenty-seventh embodiment, FIG.
As shown in FIG. 7 (a), the Viterbi decoder control circuit 1103 of FIG. 0 transmits the first symbol of each of the 20 symbols (10 symbols after S / P conversion) of each TAB signal (w1, w2, w3) From the time when the data is input to the memory 20021, each T
Until the tenth symbol of the AB signal (final symbol after S / P conversion) is input to the path memory 20021, a determined state signal is generated and output to the ACS circuit 1105.

[0540] Instead, the ACS circuit 1105 may be configured to reset the value of the path metric memory 20020 using the determinate state signal output from the Viterbi decoder control circuit 1103. That is, as shown in FIG. 120, only the determined one-state path metric is set to the minimum possible value, for example, “0”, and the other states are reset to the maximum possible value. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the Viterbi decoded data of the TMCC (BPSK: r = １ ／) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching. Can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

In Embodiment 28, FIG.
2 ACS circuit 1205 corresponds to the fourth embodiment shown in FIG.
Similarly to the above, the path metric memory 20080 and the path memory 20021 are controlled for the first six symbols (after S / P conversion) of each TAB signal using the state reduction signal output from the Viterbi decoder control circuit 1203. I was going. Then, the number of states is reduced by half until the convolution circuit 10014 is determined to be in one state.

Alternatively, the ACS circuit 1205 may be configured to reset the value of the path metric memory 20020 using the state reduction signal. That is, for the first six symbols (after S / P conversion) of each TAB signal, the determined 32, 16, 8,
Only the path metrics of the 4, 2, and 1 states are set to the minimum possible values, for example, "0", and the other states are reset to the maximum possible values. With such a configuration, the influence of the transmission mode B after the mode switching is cut off, and the Viterbi of the character multiplexed data (BPSK: r = １ ／) before the mode switching remaining in the path memory 20021 at the time of the transmission mode switching is removed. Decoded data can be output. According to such a configuration, since the value of the path metric memory 20020 is simply reset, there is an advantage that control is simplified.

[0543]

As described above, according to the first aspect of the present invention, the symbols remaining in the path memory before the switching of the transmission mode are accumulated until the last symbol of the transmission mode before the switching. Based on the metric, the minimum path metric is determined and output as Viterbi decoded data, so that Viterbi decoding can be performed without being affected by symbols in the switched transmission mode.

According to the invention of claim 2 of the present application,
For the case where transmission control information is transmitted, for the symbols before transmission mode switching remaining in the path memory,
The minimum path metric is determined based on the path metric accumulated up to the last symbol of the transmission mode before switching, and is output as Viterbi decoded data, so that Viterbi decoding that is not affected by symbols in the transmission mode after switching can be performed.

In particular, according to the third aspect of the present invention, only the one state having the minimum path metric among all the states in the last symbol before the transmission mode switching is made valid, and the other states are made invalid to make the Viterbi decoded data invalid. It is possible to perform Viterbi decoding that is not affected by the output and switched transmission mode symbols.

[0546] In particular, according to the fourth aspect of the present invention, among all states in the last symbol before the transmission mode switching, the minimum value that can take only one state path metric having the minimum path metric is set to the other state. Is reset to the maximum possible value, and Viterbi decoded data is output, so that Viterbi decoding that is not affected by symbols in the transmission mode after switching can be performed, and control can be simplified.

In particular, according to the fifth aspect of the present invention, only when the modulation multi-level number (the number of phases) after the transmission mode switching is larger than before the switching, or when the modulation multi-level number is the same and the coding rate is large, By performing Viterbi decoding which is not affected by the symbols of the transmission mode after switching, if the modulation multi-level number (phase number) after the transmission mode switching is smaller than before the switching, or if the modulation multi-level number is the same and the coding rate Is small, normal Viterbi decoding is continuously performed to improve the error rate.

In particular, according to the invention of claim 6, when a fixed symbol sequence is included following the last symbol before the transmission mode switching, the switching control in Viterbi decoding is not performed, so that the fixed symbol sequence is used. Viterbi decoding control can be made possible.

According to the seventh aspect of the present invention, when a fixed symbol sequence is included following the last symbol before transmission mode switching, the state of the convolutional encoder is determined in the fixed symbol sequence. From the symbol to the last fixed symbol to the final fixed symbol, only the determined one state is valid, and the other states are invalid, and Viterbi decoded data is output.
Using the fixed symbol sequence, it is possible to perform Viterbi decoding that is not affected by symbols in the transmission mode after switching.

According to the invention of claim 8, when transmission control information is transmitted, if a fixed symbol sequence is included following the last symbol before switching the transmission mode, the fixed symbol sequence From the symbol in which the state of the convolutional encoder is determined to the final fixed symbol, only the determined one state is valid, the other states are invalidated, Viterbi decoded data is output, and the fixed symbol sequence is used. Thus, it is possible to perform Viterbi decoding that is not affected by the symbols of the transmission mode after switching.

In particular, according to the ninth aspect of the present invention, at least one symbol is determined in a section from a symbol in which the state of the convolutional encoder is determined to a final symbol in the fixed symbol sequence. Viterbi decoding data is output with only one state being valid and other states being invalidated, using a fixed symbol sequence, performing Viterbi decoding that is not affected by symbols in the transmission mode after switching, and simplifying control. can do.

In particular, according to the tenth aspect of the present invention, when a fixed symbol sequence is included following the last symbol before the transmission mode switching, the input fixed symbol sequence includes a convolutional encoder. From the symbol whose state is determined to the final fixed symbol, Viterbi decoded data is output after being reset to the minimum value that can take only the path metric of one determined state and to the maximum value that can take another state. This makes it possible to perform the Viterbi decoding that is not affected by the symbols of the transmission mode after switching using the fixed symbol sequence, and to simplify the control.

In particular, according to the eleventh aspect of the present invention, in at least one symbol in an input fixed symbol sequence in a section from a symbol in which the state of the convolutional encoder is determined to a final fixed symbol. , Reset to the minimum value that can take only the determined one-state path metric, and reset to the maximum value that can take the other states, and output the Viterbi decoded data, and use the fixed symbol sequence to transmit after switching. Viterbi decoding that is not affected by the mode symbol can be performed, and control can be simplified.

According to the twelfth aspect of the present invention, when a fixed symbol sequence is included following the last symbol before the transmission mode switching, the state of the convolutional encoder is determined in the fixed symbol sequence. From the symbol to the final fixed symbol, for the fixed symbol sequence, of the branches output from each state in Viterbi decoding, only one branch corresponding to the fixed symbol sequence is valid, and the other branches are invalid. By outputting Viterbi decoded data and utilizing a fixed symbol sequence, it is possible to perform Viterbi decoding that is not affected by symbols in the transmission mode after switching.

According to the thirteenth aspect of the present invention, when transmission control information is transmitted, if a fixed symbol sequence is included following the last symbol before the transmission mode switching, the fixed symbol sequence From the symbol in which the state of the convolutional encoder is determined to the final fixed symbol, for the fixed symbol sequence, only one branch corresponding to the fixed symbol sequence among the branches output from each state in Viterbi decoding Is valid, the other branches are invalidated, Viterbi decoded data is output, and a fixed symbol sequence is used to perform Viterbi decoding that is not affected by symbols in the transmission mode after switching.

[0556] According to the fourteenth aspect, when a fixed symbol sequence is included following the last symbol before the transmission mode switching, convolution is performed from the first symbol in the input fixed symbol sequence. With respect to the symbols for which the state of the encoder is determined, only the state corresponding to the input up to the symbol among all the states in the Viterbi decoding is valid, and the other states are invalidated, and every time one symbol is input, After the states are reduced and the state is determined to be one, only one state is made valid, the other states are made invalid, and Viterbi decoded data is output. Viterbi decoding that is not received can be performed.

According to the fifteenth aspect of the present invention, when transmission control information is transmitted, if a fixed symbol sequence is included following the last symbol before transmission mode switching, the input fixed symbol sequence is transmitted. Of the states from the first symbol to the symbol for which the state of the convolutional encoder is determined, of the states in Viterbi decoding, only the state corresponding to the input of that symbol is valid, and the other states are valid. Is invalidated, the state is reduced every time one symbol is input, and after the state is determined, only one state is valid, the other states are invalidated, Viterbi decoded data is output, and a fixed symbol sequence is used. Viterbi decoding that is not affected by symbols in the transmission mode after switching can be performed.

According to the sixteenth aspect of the present invention, in the input fixed symbol sequence, from the first symbol to the symbol for which the state of the convolutional encoder is determined, of all the states in Viterbi decoding. Reset to the minimum value that can take only the path metric of the state corresponding to the input up to the symbol, the maximum value that can take other states, and output the Viterbi decoded data, using the fixed symbol sequence. Thus, it is possible to perform Viterbi decoding that is not affected by symbols in the transmission mode after switching, and to simplify control.

According to the seventeenth aspect of the present invention, the fixed symbol sequence is changed to the code point of the fixed symbol sequence and input to the Viterbi decoder. By using the symbol sequence, it is possible to perform Viterbi decoding that is not affected by symbols in the transmission mode after switching.

According to the eighteenth aspect of the present invention, when transmission control information is transmitted, a fixed symbol sequence is changed to a code point of the fixed symbol sequence and input to the Viterbi decoder. Decoding can be performed using a normal method, using a fixed symbol sequence, and performing Viterbi decoding that is not affected by symbols in the transmission mode after switching.

In particular, according to the nineteenth aspect, in the input fixed symbol sequence, from the first symbol to the symbol for which the state of the encoder is determined, the state is output from each state in Viterbi decoding. Of the branches, only one branch corresponding to the fixed symbol sequence is made valid, the other branches are made invalid, and Viterbi decoded data is output. The fixed symbol sequence is used to be affected by the symbol of the transmission mode after switching. No, more effective Viterbi decoding can be performed.

In particular, according to the twentieth aspect of the present invention, in the input fixed symbol sequence, from the first symbol to the symbol for which the state of the convolutional encoder is determined, out of all the states in Viterbi decoding, Only the state corresponding to the input up to the symbol is made valid, the other states are made invalid, the Viterbi decoded data is output by reducing the state each time one symbol is input, and the fixed symbol sequence is used. , It is possible to perform more effective Viterbi decoding without being affected by the symbols of the transmission mode after switching.

According to the twenty-first aspect of the present invention, in the input fixed symbol sequence, from the first symbol to the symbol in which the state of the convolutional encoder is determined, output from each state in Viterbi decoding is performed. Of the branches to be performed, only one branch corresponding to the fixed symbol sequence is valid, the other branches are invalid, and only the state corresponding to the input of the symbol is valid among all states in Viterbi decoding. The other states are invalidated, the state is reduced every time one symbol is input, the state is reduced, Viterbi-decoded data is output, and the characteristics of the fixed symbol sequence are used to the utmost, so that the influence of the symbols of the transmission mode after switching is obtained. And the most effective Viterbi decoding can be performed.

[0564] In particular, according to the invention of Claim 22, in the input fixed symbol sequence, from the first symbol to the symbol in which the state of the convolutional encoder is determined, of all the states in Viterbi decoding, Reset to the minimum value that can take only the path metric of the state corresponding to the input up to the symbol, the maximum value that can take other states, and output the Viterbi decoded data, using the fixed symbol sequence. Thus, it is possible to perform Viterbi decoding that is not affected by symbols in the transmission mode after switching, and to simplify control.

In particular, according to the invention of the twenty-third aspect, in the input fixed symbol sequence, from the first symbol to the symbol in which the state of the convolutional encoder is determined, output from each state in Viterbi decoding is performed. Path metric of a state in which only one branch corresponding to a fixed symbol sequence is made effective, other branches are made invalid, and all the states in Viterbi decoding correspond to the input up to that symbol. Reset to the minimum value that can take only the other state, and output the Viterbi decoded data by resetting it to the maximum value that can take other states, and make full use of the property of the fixed symbol sequence to obtain the symbol of the transmission mode after switching. The most effective Viterbi decoding that is not affected can be performed, and the control can be simplified.

[0566] According to the invention of claim 24, in the super frame, a data sequence to be transmitted after interleaving M slots with a depth of N for each slot is selected from the M slots of each frame. Only the data in the L slots can be deinterleaved and output.

In particular, the invention according to claim 25 is characterized in that the maximum number of slots per frame selected is Lmax.
Deinterleaving can be performed by using only the minimum necessary memory area using two banks of the area only for the maximum (Lmax × N) slots of the memory circuit.

In particular, according to the twenty-sixth aspect, of the M slots of each frame, only the data of the selected L slot is deinterleaved and the L of the transmission format is
/ M can be output continuously.

According to the twenty-seventh aspect of the present invention, in a transmission system for transmitting data in a transmission format in which a plurality of MPEG transport streams are multiplexed, in a superframe, an interleave having a depth of N per slot is M slots. The data sequence that is transmitted separately can be output by deinterleaving only the data of the selected L slots out of the M slots of each frame.

According to the invention of claim 28, if the maximum number of slots per frame occupied by one type of transport stream is Lmax, only the maximum (Lmax × N) slots of the memory circuit are provided. By using two areas and using only the minimum necessary memory area, it is possible to deinterleave only one type of selected transport stream and output data.

According to the invention of claim 29, if the maximum number of slots per frame occupied by one type of transport stream is Lmax and K is an integer of 2 or more, the maximum (Lmax × N × K) It is possible to output data by deinterleaving only the selected K or less types of transport streams using only the minimum necessary memory area using two banks of only the area corresponding to the slots. it can.

[0572] In particular, according to the invention of the thirtieth aspect, in a transmission system in which transmission is performed in a transmission format in which a plurality of MPEG transport streams are multiplexed, only data of a selected L slot among M slots of each frame is provided. Is de-interleaved and the transmission format L / M
It can output continuously at the speed of

[0573] According to the invention of the thirty-first aspect, in a transmission system for transmitting in a transmission format in which a plurality of MPEG transport streams are multiplexed, each of the selected J types of transport streams includes one transport stream.
Assuming that L1, L2,..., Lj slots are occupied per frame, de-interleaving of a total of (L1 + L2 +... + Lj) slots per frame out of M slots of each frame is performed. .. + Lj) / M.

According to the thirty-second aspect of the present invention, when 1 frame = M slots and 1 superframe = N frames, a data sequence that is continuously randomized and transmitted in superframe units is 1 frame. It has de-randomized (N × M) kinds of initial values for the first data of each (N × M) slot in the superframe, and data of L slot out of M slots of each frame, which has already been selected, is inputted. Then, de-randomization for each input slot can be performed from the initial value corresponding to each input slot.

According to the invention of claim 33, when transmission control information is transmitted, when 1 frame = M slots and 1 superframe = N frames,
A data sequence that is continuously randomized and transmitted in units of superframes has an initial value of (N × M) types of de-randomization for each head data of (N × M) slots in one superframe. Then, when data of L slots among the M slots of each frame that has been selected is input, de-randomization for each input slot can be performed from the initial value corresponding to the input slot. .

According to the invention of claim 34, of the M slots of each frame, only the data of the selected L slot is read / written from / to the memory circuit, so that the data of the L slot per one selected frame is stored. , And can be output continuously at the L / M speed of the transmission format.

In particular, if the maximum number of slots per frame to be selected is Lmax, an area corresponding to the maximum Lmax slots of the memory circuit is used, and only the minimum required memory area is used. Accordingly, the selected data can be continuously output after performing the speed conversion.

[0578] According to the invention of claim 36, in a transmission system for transmitting in a transmission format in which a plurality of MPEG transport streams are multiplexed, only data of a selected L slot out of M slots of each frame is transmitted. Is read / written to / from the memory circuit, data of L slots per selected frame can be continuously output at the L / M speed of the transmission format.

In particular, according to the thirty-seventh aspect, assuming that the maximum number of slots per frame occupied by one type of transport stream is Lmax, an area corresponding to only the maximum Lmax slots of the memory circuit is used. By using only the minimum necessary memory area, one type of selected transport stream can be subjected to speed conversion and output continuously.

In particular, when the maximum number of slots per frame occupied by one type of transport stream is Lmax and K is an integer of 2 or more, the maximum (Lmax × K) Using only the area corresponding to the slots and using only the minimum necessary memory area, the selected K or less types of transport streams can be subjected to speed conversion and output continuously.

According to the thirty-ninth aspect of the present invention, it is assumed that the selected J types of transport streams occupy L1, L2,..., Lj slots per frame. Of the transport format L1 / M, L2
/ M,..., Lj / M.

In particular, according to the forty-fourth aspect, of the M slots of each frame, only the data of the selected L slot is deinterleaved, and the data sequence of the already selected L slot per frame is represented by: The speed conversion circuit can continuously output a data sequence at the L / M speed of the transmission format.

In particular, if the maximum number of slots per frame to be selected is Lmax, only the data of the selected slot is deinterleaved, and only the maximum Lmax slots of the memory circuit are used. The selected data can be subjected to speed conversion and output continuously by using only the minimum necessary memory area.

[0584] In particular, according to the invention of Claim 42, in a transmission system in which transmission is performed in a transmission format in which a plurality of MPEG transport streams are multiplexed, only data of a selected L slot out of M slots of each frame is transmitted. And the rate conversion circuit can continuously output the data series of L slots per frame already selected at the L / M rate of the transmission format.

In particular, according to the invention of claim 43, in a transmission system in which transmission is performed in a transmission format in which a plurality of MPEG transport streams are multiplexed, one type of transport stream occupies a maximum per frame. Assuming that the number of slots is Lmax, only the data of the selected slot is deinterleaved, an area of only the maximum Lmax slots of the memory circuit is used, and one type of channel selected by only the minimum necessary memory area is used. The transport stream can be continuously output with a speed conversion.

[0586] In particular, according to the invention of claim 44, in a transmission system in which transmission is performed in a transmission format in which a plurality of MPEG transport streams are multiplexed, one type of transport stream occupies a maximum per frame. Assuming that the number of slots is Lmax and K is an integer of 2 or more, only the data of the selected slot is deinterleaved, the area of only the maximum (Lmax × K) slots of the memory circuit is used, and the necessary minimum memory is used. By using only the area, the selected K or less types of transport streams can be subjected to speed conversion and output continuously.

In particular, according to the forty-fifth aspect of the present invention, in a transmission system for transmitting in a transmission format in which a plurality of MPEG transport streams are multiplexed, each of the selected J types of transport streams includes one transport stream.
Assuming that L1, L2,..., Lj slots are occupied per frame, only the data of the selected slot is deinterleaved, and J types of transport streams are transmitted in L1 / M, L2 of the transmission format, respectively.
/ M,..., Lj / M.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an entire configuration of an error correction circuit according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a Viterbi decoder according to the first embodiment.

FIG. 3 is an explanatory diagram showing a state (trellis diagram) of a path memory at the time of transmission mode switching in the first embodiment.

FIG. 4 is an explanatory diagram of another example showing a state (trellis diagram) of the path memory at the time of transmission mode switching in the first embodiment.

FIG. 5 is a block diagram illustrating an entire configuration of an error correction circuit according to a second embodiment of the present invention.

FIG. 6 is a block diagram illustrating a configuration of a Viterbi decoder according to the second embodiment.

FIG. 7 is an explanatory diagram showing a state (trellis diagram) of a path memory at the time of transmission mode switching in the second embodiment.

FIG. 8 is a block diagram showing an entire configuration of an error correction circuit according to a third embodiment of the present invention.

FIG. 9 is a block diagram illustrating a configuration of a Viterbi decoder according to the third embodiment.

FIG. 10 is an explanatory diagram illustrating a branch output method at the time of transmission mode switching in the third embodiment.

FIG. 11 is a block diagram showing an overall configuration of an error correction circuit according to a fourth embodiment of the present invention.

FIG. 12 is a block diagram illustrating a configuration of a Viterbi decoder according to a fourth embodiment.

FIG. 13 is an explanatory diagram showing a method of reducing the state of a trellis diagram at the time of transmission mode switching in Embodiment 4.

FIG. 14 is a block diagram illustrating an entire configuration of an error correction circuit according to a fifth embodiment of the present invention.

FIG. 15 is a block diagram illustrating a configuration of a Viterbi decoder according to the fifth embodiment.

FIG. 16 is an explanatory diagram showing a method of converting fixed sequence I / Q coordinates in the fifth embodiment.

FIG. 17 is an explanatory diagram showing a transmission frame configuration used for a simulation in the fifth embodiment.

FIG. 18 is an explanatory diagram showing a simulation result in the fifth embodiment.

FIG. 19 is a block diagram illustrating an overall configuration of an error correction circuit according to a sixth embodiment of the present invention.

FIG. 20 is a block diagram illustrating a configuration of a Viterbi decoder according to Embodiment 6.

FIG. 21 is a block diagram illustrating an overall configuration of an error correction circuit according to a seventh embodiment of the present invention.

FIG. 22 is a block diagram illustrating a configuration of a Viterbi decoder according to the seventh embodiment.

FIG. 23 is a block diagram illustrating an overall configuration of an error correction circuit according to an eighth embodiment of the present invention.

FIG. 24 is a block diagram illustrating a configuration of a Viterbi decoder according to the eighth embodiment.

FIG. 25 is a block diagram showing an entire configuration of an error correction circuit according to a ninth embodiment of the present invention.

FIG. 26 is a block diagram illustrating a configuration of a Viterbi decoder according to the ninth embodiment.

FIG. 27 is a block diagram showing an entire configuration of an error correction circuit according to a tenth embodiment of the present invention.

FIG. 28 is a block diagram illustrating a configuration of a Viterbi decoder according to Embodiment 10.

FIG. 29 is a block diagram showing an entire configuration of an error correction circuit according to Embodiment 11 of the present invention.

FIG. 30 is a block diagram illustrating a configuration of a Viterbi decoder according to Embodiment 11.

FIG. 31 is a block diagram showing an entire configuration of an error correction circuit according to a twelfth embodiment of the present invention.

FIG. 32 is a block diagram illustrating a configuration of a Viterbi decoder according to Embodiment 12.

FIG. 33 is a block diagram showing an entire configuration of an error correction circuit according to a thirteenth embodiment of the present invention.

FIG. 34 is a block diagram showing a configuration of a deinterleave circuit according to the thirteenth embodiment.

FIG. 35 is an explanatory diagram showing an output data sequence from a de-interleave circuit in the thirteenth embodiment.

FIG. 36 is a block diagram showing an entire configuration of an error correction circuit according to a fourteenth embodiment of the present invention.

FIG. 37 is a block diagram illustrating a configuration of a de-interleave circuit according to Embodiment 14.

FIG. 38 is an explanatory diagram showing an output data sequence from a de-interleave circuit in the fourteenth embodiment.

FIG. 39 is a block diagram showing a configuration of a de-randomizing circuit according to a fourteenth embodiment.

FIG. 40 is an explanatory diagram showing a state of generating a gate signal and an initial value in the de-randomizing circuit according to the fourteenth embodiment.

FIG. 41 is a block diagram showing an overall configuration of an error correction circuit according to Embodiment 15 of the present invention.

FIG. 42 is a block diagram showing a configuration of a speed conversion circuit in the fifteenth embodiment.

FIG. 43 is a block diagram showing an overall configuration of another example of the error correction circuit according to Embodiment 15 of the present invention.

FIG. 44 is a block diagram showing a configuration of another example of the speed conversion circuit in the fifteenth embodiment.

FIG. 45 is a block diagram showing an overall configuration of an error correction circuit according to Embodiment 16 of the present invention.

FIG. 46 is a block diagram showing a configuration of a speed conversion circuit in the sixteenth embodiment.

FIG. 47 is a block diagram showing an overall configuration of another example of the error correction circuit according to Embodiment 16 of the present invention.

FIG. 48 is a block diagram showing another example of the configuration of the speed conversion circuit in the sixteenth embodiment.

FIG. 49 is a block diagram illustrating an overall configuration of an error correction encoding device according to Embodiments 17 to 32 of the present invention.

FIG. 50 is an explanatory diagram showing an output data sequence up to a randomizing circuit in the error correction encoding device according to Embodiments 17 to 32.

FIG. 51 is a diagram illustrating a byte data sequence having a superframe structure input to a byte / symbol circuit in the error correction encoding device according to any of Embodiments 17 to 32.

FIG. 52 is an explanatory diagram illustrating an example of the number of slots in each transmission mode of the superframe structure in Embodiments 17 to 32 of the present invention.

FIG. 53 is an explanatory diagram showing an output data sequence from input to output in the error correction encoding devices according to Embodiments 17 to 32.

FIG. 54 is a block diagram showing an entire configuration of an error correction circuit according to a seventeenth embodiment of the present invention.

FIG. 55 is a block diagram showing an entire configuration of an error correction circuit according to Embodiment 18 of the present invention.

FIG. 56 is a block diagram showing an entire configuration of an error correction circuit according to a nineteenth embodiment of the present invention.

FIG. 57 is a block diagram showing an entire configuration of an error correction circuit according to a twentieth embodiment of the present invention.

FIG. 58 is a block diagram showing an entire configuration of an error correction circuit according to a twenty-first embodiment of the present invention.

FIG. 59 is a block diagram showing an entire configuration of an error correction circuit according to a twenty-second embodiment of the present invention.

FIG. 60 is a block diagram showing an entire configuration of an error correction circuit according to a twenty third embodiment of the present invention.

FIG. 61 is a block diagram showing an overall configuration of an error correction circuit according to a twenty-fourth embodiment of the present invention.

FIG. 62 is a block diagram showing an entire configuration of an error correction circuit according to a twenty-fifth embodiment of the present invention.

FIG. 63 is a block diagram showing an overall configuration of an error correction circuit according to Embodiment 26 of the present invention.

FIG. 64 is a block diagram showing an entire configuration of an error correction circuit according to a twenty-seventh embodiment of the present invention.

FIG. 65 is a block diagram showing an entire configuration of an error correction circuit according to a twenty-eighth embodiment of the present invention.

FIG. 66 is a block diagram showing an entire configuration of an error correction circuit according to a twenty-ninth embodiment of the present invention.

FIG. 67 is a block diagram showing an entire configuration of an error correction circuit according to Embodiment 30 of the present invention.

FIG. 68 is a block diagram showing an overall configuration of an error correction circuit according to Embodiment 31 of the present invention.

FIG. 69 is a block diagram illustrating a configuration of a speed conversion circuit in Embodiment 31.

FIG. 70 is a block diagram showing an overall configuration of another example of the error correction circuit according to Embodiment 31 of the present invention.

FIG. 71 is a block diagram illustrating a configuration of another example of the speed conversion circuit in Embodiment 31;

FIG. 72 is a block diagram showing an entire configuration of an error correction circuit according to a thirty-second embodiment of the present invention.

FIG. 73 is a block diagram illustrating a configuration of a speed conversion circuit according to Embodiment 32.

FIG. 74 is a block diagram showing an overall configuration of another example of the error correction circuit according to Embodiment 32 of the present invention.

FIG. 75 is a block diagram showing a configuration of another example of the speed conversion circuit in the thirty-second embodiment.

FIG. 76 is a block diagram showing the entire configuration of an error correction encoding device in a conventional example.

FIG. 77 is an explanatory diagram showing an output data sequence up to a randomizing circuit in an error correction encoding device in a conventional example.

FIG. 78 is an explanatory diagram showing a state of interleaving in a conventional error correction encoding device.

FIG. 79 is an explanatory diagram showing dummy slots in the conventional error correction coding device.

FIG. 80 is a block diagram showing a configuration of a transmission control information generation circuit in a conventional example.

FIG. 81 is an explanatory diagram showing an example of the contents of the entire TMCC in the conventional example.

FIG. 82 is an explanatory diagram showing an example of the content of transmission mode / slot information in a conventional TMCC.

FIG. 83 is an explanatory diagram showing an example of the content of relative TS / slot information in a conventional TMCC.

FIG. 84 shows a relative TS / TS in a conventional TMCC.
It is an explanatory view showing an example of the contents of a number correspondence table.

FIG. 85 is an explanatory diagram showing an example of the content of transmission / reception control information in a conventional TMCC.

FIG. 86 is an explanatory diagram showing an example of the contents of extended information in a conventional TMCC.

FIG. 87 is an explanatory diagram showing a superframe-structured byte data sequence input to a byte / symbol circuit in an error correction encoding device in a conventional example.

FIG. 88 is an explanatory diagram showing how a gate signal is generated in a randomizing circuit of a conventional error correction encoding device.

FIG. 89 is an explanatory diagram showing an example of a superframe structure in a conventional example.

FIG. 90 is an explanatory diagram showing a state of a byte / symbol in a byte / symbol circuit in a conventional error correction encoding device.

FIG. 91 is a block diagram illustrating a configuration of a convolutional encoder in a conventional example.

FIG. 92 is an explanatory diagram showing a state of TC-8PSK (r = ２) convolutional coding, punctured processing, and P / S conversion in a convolutional encoder of a conventional error correction coding apparatus. It is.

FIG. 93 is a diagram illustrating the state of convolutional coding, puncturing, and P / S conversion in the case of QPSK (r = 3/4) in the convolutional encoder of the conventional error correction coding apparatus. FIG.

FIG. 94 is a diagram illustrating a state of convolutional coding, puncturing, and P / S conversion in the case of QPSK (r = １ ／) in a convolutional encoder of a conventional error correction coding apparatus. FIG.

FIG. 95 is a diagram illustrating a state of convolutional encoding, puncturing, and P / S conversion in the case of BPSK (r = １ ／) in a convolutional encoder of a conventional error correction encoding device. FIG.

FIG. 96 is an explanatory diagram showing a state of mapping in a mapping circuit of a conventional error correction encoding device.

FIG. 97 is an explanatory diagram showing an output data sequence from input to output in a conventional error correction encoding device.

FIG. 98 is a block diagram showing an overall configuration of an error correction circuit in a conventional example.

FIG. 99 is a block diagram showing a configuration of a transmission control information decoding circuit in a conventional example.

FIG. 100 is a block diagram showing a configuration of a conventional Viterbi decoder and a high / low hierarchy selection signal generation circuit.

FIG. 101 shows a conventional Viterbi decoder, TC-8
FIG. 9 is an explanatory diagram showing the state of Viterbi decoding, depuncturing processing, and S / P conversion in the case of PSK (r = ／).

FIG. 102 shows a conventional Viterbi decoder which uses QPSK
FIG. 9 is an explanatory diagram illustrating the state of Viterbi decoding, depuncturing processing, and S / P conversion in the case of (r = 3/4).

FIG. 103 shows a conventional Viterbi decoder which uses QPSK
It is explanatory drawing which shows a mode of Viterbi decoding, de-punctured processing, and S / P conversion in case of (r = 1/2).

FIG. 104 shows a conventional Viterbi decoder which uses BPSK.
It is explanatory drawing which shows a mode of Viterbi decoding, de-punctured processing, and S / P conversion in case of (r = 1/2).

FIG. 105 shows a conventional Viterbi decoder, TC-8
FIG. 4 is an explanatory diagram showing a trellis diagram for PSK.

FIG. 106 shows a conventional Viterbi decoder which uses QPSK.
FIG. 4 is an explanatory diagram showing a trellis diagram for BPSK and BPSK.

FIG. 107 is an explanatory diagram showing how symbol / byte conversion is performed by a symbol / byte circuit in a conventional error correction circuit.

FIG. 108 is an explanatory diagram showing an output data sequence from input to output in an error correction circuit in a conventional example.

FIG. 109 is an explanatory diagram showing a state of de-interleaving in a de-interleaving circuit of a conventional error correction circuit.

FIG. 110 is a block diagram showing a configuration of a de-interleaving circuit in a conventional example.

FIG. 111 is a block diagram showing a configuration of a de-randomizing circuit in a conventional example.

FIG. 112 is an explanatory diagram showing how a gate signal is generated in a conventional de-randomizing circuit.

FIG. 113 is a block diagram illustrating a configuration of a speed conversion circuit in a conventional example.

FIG. 114 is an explanatory diagram showing a state of speed conversion in a speed conversion circuit of a conventional error correction circuit.

FIG. 115 is an explanatory diagram showing a state of speed conversion in a speed conversion circuit of a conventional error correction circuit.

FIG. 116 is an explanatory diagram showing a state of speed conversion in a speed conversion circuit of a conventional error correction circuit.

FIG. 117 is an explanatory diagram showing a state of speed conversion in a speed conversion circuit of a conventional error correction circuit.

FIG. 118 is an explanatory diagram showing a state (trellis diagram) of a path memory at the time of transmission mode switching in a conventional example.

FIG. 119 is an explanatory diagram showing an example of a state (trellis diagram) of the path memory at the time of transmission mode switching in the first embodiment.

120 is an explanatory diagram of an example showing a state (trellis diagram) of a path memory at the time of transmission mode switching in Embodiment 2. FIG.

FIG. 121 is an explanatory diagram showing a transmission frame configuration used for simulation in the second embodiment.

FIG. 122 is an explanatory diagram showing simulation results in the second embodiment.

[Explanation of symbols]

101, 201, 301, 401, 501, 601, 7
01,801,901,1001,1101,120
1,1301,1401,1501,1507,160
1,1607,1703,1801,1901,200
1,101,2201,301,2401,250
1,601,2701,2801,2901,300
1,3101,3102,3201,3202,200
01 error correction circuit 102, 202, 302, 402, 602, 702, 8
02,902,1002,1102,1202,200
02 Viterbi decoder 103, 203, 303, 403, 503, 603, 7
03,803,903,1003,1103,1203
Viterbi decoder control circuit 104, 204, 304, 404, 604, 704, 8
04,904,1004,1104,1204,200
17 Viterbi decoding circuit 105, 205, 305, 405, 605, 705, 8
05,905,1005,1105,1205,200
19 ACS circuit 506 Input symbol conversion circuit 1302, 1402, 20005 De-interleave circuit 1303, 1403, 1503, 1509, 1603
1609, 1705, 20011 Tuning circuit 1304, 1404, 1504, 1510, 1604
1610, 20026, 20034 Write address generation circuit 1305, 1405, 1505, 1511, 1605
1611, 20027, 20035 Read address generation circuits 1306, 1406, 1506, 1512, 1606
1612, 20028, 20036 Memory circuit 1407, 20007, 20012 De-randomizing circuit 1408, 20002 PN generating circuit 1409 Initial value generating circuit 1502, 1508, 1602, 1608, 200009
Speed conversion circuit 1701, 10001 Error correction coding device 1702 TAB / data information generation circuit 1704 Control signal generation circuit 10002 TS multiplexing circuit 10003, 10011 RS coding circuit 10004 Randomizing circuit 10005 Interleave circuit 10006 Byte / symbol conversion circuit 10007 Convolutional code Transformer 10008 Mapping circuit 10009 Transmission control information generation circuit 10010 Control information generation unit 10012 TAB signal insertion unit 10013 Randomization circuit 10014, 20005 Convolution circuit 10015 Punctured P / S circuit 20003 High / low hierarchy selection signal generation circuit 20004, 20013 Symbol / byte conversion circuit 20006 MPEG synchronization byte / dummy slot insertion circuit 200008, 20004 RS decoding circuit 20010 Transmission control information decoding circuit 20005 TMCC decoding circuit 2006 De-punctured S / P circuit 20008 Branch metric calculation circuit 20080 Path metric memory 20021 Path memory 22022 8PSK hard decision circuit 200023 M stage delay circuit 200024 BER measurement circuit 20030 P / S conversion circuit 20031 S / P conversion circuit 20032 Gate signal generation circuit 20033 ex-or circuit

Continuing on the front page (72) Inventor Yoshikazu Hayashi 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Yasuhiro Nakakura 1006 Oji Kadoma Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. Person Takehiro Kamata 1006 Kadoma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (45)

[Claims] 1. A data sequence on a transmission side is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and each symbol continuously exceeds one modulation scheme and coding rate.
An error correction circuit for performing Viterbi decoding of a data sequence convoluted and transmitted by two convolutional encoders, and outputs a minimum path metric when outputting Viterbi decoded data at the time of switching a modulation method and a coding rate. When a signal for switching symbols to be determined in the path memory is used as a switching control signal, according to the known modulation scheme / coding rate information between transmission and reception, corresponding to the modulation scheme and coding rate of each input symbol. While performing the Viterbi decoding, when switching the modulation method and the coding rate, during the period when the switching control signal is output, a Viterbi decoder that outputs Viterbi decoded data with a path metric accumulated up to the last symbol before switching Providing the modulation scheme / coding rate information of each symbol input to the Viterbi decoder to the Viterbi decoder, At the time of switching of the coding rate, a period in which the symbol of the modulation scheme and the coding rate before switching remains in the path memory of the Viterbi decoder, the switching control signal is generated, and the Viterbi decoder to be provided to the Viterbi decoder And a control circuit. 2. A transmission frame is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and information on a modulation scheme and a coding rate of each symbol is included as transmission control information for each frame. Is an error correction circuit that Viterbi-decodes a data sequence transmitted by being convolutionally coded by one convolutional coder continuously over different modulation schemes and coding rates. When outputting the Viterbi decoded data at the time of rate switching, when a signal for switching the symbol for determining the minimum path metric in the path memory is used as a switching control signal, according to the known modulation scheme / coding rate information between transmission and reception. Perform Viterbi decoding corresponding to the modulation scheme and coding rate of each input symbol, and at the time of switching the modulation scheme and coding rate, A Viterbi decoder that outputs Viterbi decoded data with a path metric accumulated up to the last symbol before switching during a period in which the switching control signal is output, and a transmission control information decoding circuit that decodes the transmission control information included in each frame From the decoding result output from the transmission control information decoding circuit, the modulation scheme / coding rate information of each symbol input to the Viterbi decoder is given to the Viterbi decoder, and the modulation scheme and coding rate At the time of switching, a period in which the symbol of the modulation scheme and the coding rate before switching remains in the path memory of the Viterbi decoder, generates the switching control signal, and supplies a Viterbi decoder control circuit to the Viterbi decoder. An error correction circuit, comprising: 3. The Viterbi decoder control circuit, wherein the modulation scheme / coding rate information of each symbol input to the Viterbi decoder is provided to the Viterbi decoder, and when the modulation scheme and the coding rate are switched, Of all the states in the last symbol before switching, only one state having the minimum path metric is made valid, and the switching control signal for invalidating the other states is generated and replaced with a configuration to be given to the Viterbi decoder. 3. The error correction circuit according to claim 1, wherein: 4. The Viterbi decoder control circuit, wherein the modulation scheme / coding rate information of each symbol input to the Viterbi decoder is provided to the Viterbi decoder, and when the modulation scheme and the coding rate are switched, The switching control signal for resetting to the minimum value that can take only the path metric of one state having the minimum path metric among all states in the last symbol before switching, and the maximum value that can take other states. 3. The error correction circuit according to claim 1, wherein the error correction circuit is replaced with a configuration that generates and supplies the generated configuration to the Viterbi decoder. 5. The Viterbi decoder control circuit according to claim 1, wherein the modulation multi-level number after the switching of the modulation scheme and the coding rate is larger than before the switching, or only when the modulation multi-level number is the same and the coding rate is large, The error correction circuit according to claim 1, wherein the switching control signal is generated and provided to the Viterbi decoder. 6. The switching control signal, when a modulation scheme and a coding rate are switched, when a fixed symbol sequence for termination is included following the last symbol before switching. The error correction circuit according to any one of claims 1 to 5, wherein the error correction circuit does not generate the error correction signal. 7. A data sequence on the transmission side is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and at the time of switching between the modulation schemes and the coding rates, is used for termination after the last symbol before switching. There is a case where a fixed symbol sequence is included, and each symbol exceeds a different modulation scheme and coding rate, and Viterbi-decodes a data sequence transmitted by being convolutionally encoded by one convolutional encoder continuously. An error correction circuit, wherein, for a fixed symbol sequence, when a signal indicating a period during which the state of the convolutional encoder is determined is defined as a determined state signal, an input is performed in accordance with a known modulation method and coding rate information between transmission and reception. Performs the Viterbi decoding corresponding to the modulation scheme and the coding rate of each of the symbols, and, when the modulation scheme and the coding rate are switched, the Viterbi decoding corresponding to the determined state signal. A Viterbi decoder that performs decoding, the modulation scheme / coding rate information of each symbol input to the Viterbi decoder is given to the Viterbi decoder, and when the modulation scheme and the coding rate are switched, the last symbol before switching is given. Followed by a fixed symbol sequence for termination,
In the input fixed symbol sequence, from the symbol in which the state of the convolutional encoder is determined to the final fixed symbol, only the determined one state is valid,
An error correction circuit, comprising: a Viterbi decoder control circuit that generates the confirmed state signal for invalidating another state and supplies the generated signal to the Viterbi decoder. 8. A transmission frame is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and at the time of switching of a modulation scheme and a coding rate, a fixed symbol sequence for termination following a last symbol before the switching. And information about the modulation scheme and coding rate of each symbol is included as transmission control information for each frame, and the symbols of each frame exceed the different modulation schemes and coding rates, An error correction circuit for Viterbi-decoding a data sequence convolutionally coded and transmitted by a convolutional coder, wherein a signal indicating a period during which the state of the convolutional coder is determined for a fixed symbol sequence is determined. When the state signal, according to the modulation scheme and coding rate information, while performing the Viterbi decoding corresponding to the modulation scheme and coding rate of each input symbol, When switching between the modulation scheme and the coding rate, a Viterbi decoder that performs Viterbi decoding corresponding to the determined state signal, a transmission control information decoding circuit that decodes the transmission control information included in each frame, and the transmission control From the decoding result output from the information decoding circuit, extract the modulation scheme and coding rate information of each symbol input to the Viterbi decoder and provide it to the Viterbi decoder, when switching the modulation scheme and coding rate, When a fixed symbol sequence for termination is included following the last symbol before switching, in the input fixed symbol sequence, from the symbol in which the state of the convolutional encoder is determined to the final fixed symbol. For the Viterbi decoding, the determined state signal for validating only the determined one state and invalidating the other states is generated and supplied to the Viterbi decoder. Error correction circuit, characterized by comprising: a control circuit. 9. The Viterbi decoder control circuit extracts the modulation scheme / coding rate information of each symbol input to the Viterbi decoder, and supplies the extracted modulation scheme / coding rate information to the Viterbi decoder to switch a modulation scheme and a coding rate. Sometimes, when a fixed symbol sequence for termination is included following the last symbol before switching, the input fixed symbol sequence is changed from the symbol in which the state of the convolutional encoder is determined to the final fixed symbol. In at least one symbol, a valid state signal for validating only one state in which the state of the convolutional encoder is determined and invalidating other states is generated for at least one symbol; 9. The error correction circuit according to claim 7, wherein the error correction circuit is replaced with a configuration given in (1). 10. The Viterbi decoder control circuit, wherein the modulation scheme / coding rate information of each symbol input to the Viterbi decoder is provided to the Viterbi decoder, and when the modulation scheme and the coding rate are switched, When a fixed symbol sequence for termination is included following the last symbol before switching,
In the input fixed symbol sequence, from the symbol in which the state of the convolutional encoder is determined to the final fixed symbol, the minimum value that can take only the determined one-state path metric is set to another value. 9. The error correction circuit according to claim 7, wherein the deterministic state signal for resetting the state to a maximum value capable of taking a state is generated and is provided to the Viterbi decoder. 11. The Viterbi decoder control circuit, wherein the modulation scheme / coding rate information of each symbol input to the Viterbi decoder is provided to the Viterbi decoder, and when the modulation scheme and the coding rate are switched, When a fixed symbol sequence for termination is included following the last symbol before switching,
In the input fixed symbol sequence, in a section from the symbol in which the state of the convolutional encoder is determined to the final fixed symbol, at least one symbol can take only the determined one-state path metric. 9. The error according to claim 7, wherein the deterministic state signal for resetting to a minimum value to a maximum value that can take another state is generated and the configuration is given to the Viterbi decoder. Correction circuit. 12. A data sequence on the transmitting side is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and when switching between the modulation schemes and the coding rates, is performed for termination after the last symbol before switching. There is a case where a fixed symbol sequence is included, and each symbol exceeds a different modulation scheme and coding rate, and Viterbi-decodes a data sequence transmitted by being convolutionally encoded by one convolutional encoder continuously. An error correction circuit, wherein, for a fixed symbol sequence, when a signal specifying a branch in a state transition of a trellis diagram is a fixed branch signal, each signal input according to a known modulation scheme / coding rate information between transmission and reception. Performs Viterbi decoding corresponding to the modulation scheme and coding rate of the symbol, and switches the modulation scheme and coding rate to the fixed branch signal. A Viterbi decoder that performs the above-mentioned Viterbi decoding, and the modulation scheme / coding rate information of each symbol input to the Viterbi decoder is given to the Viterbi decoder, and when the modulation scheme and the coding rate are switched, When a fixed symbol sequence for termination is included following the last symbol,
For the fixed symbol sequence, of the branches output from each state in Viterbi decoding, only the one branch corresponding to the fixed part vol sequence is made valid, and the fixed branch signal for invalidating the other branch is generated. And a Viterbi decoder control circuit provided to the Viterbi decoder. 13. A transmission frame is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and at the time of switching of a modulation scheme and a coding rate, a fixed symbol sequence for termination following a last symbol before the switching. In some cases,
Information about the modulation scheme / coding rate of each symbol is included as transmission control information for each frame, and the symbols of each frame exceed the different modulation schemes and coding rates, and are continuously 1 bit.
An error correction circuit for performing Viterbi decoding of a data sequence convoluted and transmitted by two convolutional encoders, wherein a fixed symbol sequence is a fixed branch signal that specifies a branch in a state transition of a trellis diagram. In accordance with the modulation scheme / coding rate information, while performing the Viterbi decoding corresponding to the modulation scheme and coding rate of each input symbol, and at the time of switching the modulation scheme and coding rate, the fixed branch signal A Viterbi decoder that performs Viterbi decoding corresponding to: a transmission control information decoding circuit that decodes the transmission control information included in each frame; and a decoding result output from the transmission control information decoding circuit. The modulation method / coding rate information of each input symbol is extracted and given to the Viterbi decoder, and the modulation method and code At the time of rate switching, if a fixed symbol sequence for termination is included following the last symbol before switching, the fixed symbol sequence is included in the fixed symbol sequence among branches output from each state in Viterbi decoding. Only one corresponding branch is valid,
An error correction circuit comprising: a Viterbi decoder control circuit that generates the fixed branch signal for invalidating another branch and supplies the generated signal to the Viterbi decoder. 14. A data sequence on the transmission side is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and at the time of switching between the modulation schemes and the coding rates, is used for termination after the last symbol before switching. There is a case where a fixed symbol sequence is included, and each symbol exceeds a different modulation scheme and coding rate, and Viterbi-decodes a data sequence transmitted by being convolutionally encoded by one convolutional encoder continuously. An error correction circuit, for a fixed symbol sequence, when a signal for reducing the number of states of a trellis diagram is used as a state reduction signal, according to known modulation scheme / coding rate information between transmission and reception, A Viterbi decoder that performs Viterbi decoding corresponding to the modulation scheme and coding rate and performs Viterbi decoding corresponding to the state reduction signal when the modulation scheme and coding rate are switched. A decoder, and the modulation scheme / coding rate information of each symbol input to the Viterbi decoder is provided to the Viterbi decoder, and when the modulation scheme and the coding rate are switched, termination is performed after the last symbol before switching. If a fixed symbol sequence for
In the input fixed symbol sequence, from the first symbol to the symbol for which the state of the convolutional encoder is determined, only the state corresponding to the input of the symbol is input out of all the states in Viterbi decoding. Is valid, the other states are invalidated, the state is reduced every time one symbol is input, and after the state is determined to be one, only the one state is valid, and the state reduction signal for invalidating the other states is transmitted. And a Viterbi decoder control circuit for generating and providing the Viterbi decoder to the Viterbi decoder. 15. A transmission frame is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and at the time of switching of a modulation scheme and a coding rate, a fixed symbol sequence for termination following a last symbol before switching. In some cases,
Information about the modulation scheme / coding rate of each symbol is included as transmission control information for each frame, and the symbols of each frame exceed the different modulation schemes and coding rates, and are continuously 1 bit.
An error correction circuit for Viterbi decoding of a data sequence transmitted by being convolutionally encoded by two convolutional encoders, wherein a signal for reducing the number of states of a trellis diagram for a fixed symbol sequence is used as a state reduction signal. When performing the Viterbi decoding corresponding to the modulation scheme and coding rate of each input symbol according to the modulation scheme and coding rate information, and at the time of switching the modulation scheme and coding rate, it corresponds to the state reduction signal. A Viterbi decoder that performs the obtained Viterbi decoding, a transmission control information decoding circuit that decodes the transmission control information included in each frame, and a decoding result output from the transmission control information decoding circuit, which is input to the Viterbi decoder. The modulation scheme / coding rate information of each symbol to be extracted is provided to the Viterbi decoder, and when the modulation scheme and the coding rate are switched, the most recent data before switching is obtained. When a fixed symbol sequence for termination is included following a symbol, Viterbi is used for the input fixed symbol sequence from the symbol in which the state of the convolutional encoder is determined to the final fixed symbol. Of all the states in decoding, only the state corresponding to the input up to that symbol is made valid, the other states are invalidated, and the state is reduced every time one symbol is input.
An error correction circuit, comprising: a Viterbi decoder control circuit that generates the state reduction signal for validating only a state and invalidating other states and provides the generated signal to the Viterbi decoder. 16. The Viterbi decoder control circuit, wherein the modulation scheme / coding rate information of each symbol input to the Viterbi decoder is provided to the Viterbi decoder, and when the modulation scheme and the coding rate are switched, When a fixed symbol sequence for termination is included following the last symbol before switching,
In the input fixed symbol sequence, from the symbol in which the state of the convolutional encoder is determined to the final fixed symbol, a state corresponding to the input of all the states in the Viterbi decoding. Is reset to the minimum value that can take only the path metric of the other state, the maximum value that can take the other state, and after it is determined to be one state, the minimum value that can take only the path metric of the determined one state is:
16. The error correction circuit according to claim 14, wherein the state reduction signal for resetting the state to a maximum value that can take another state is replaced with a configuration to be provided to the Viterbi decoder. 17. A data sequence on the transmission side is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and at the time of switching between the modulation schemes and the coding rates, is used for termination after the last symbol before switching. There is a case where a fixed symbol sequence is included, and each symbol exceeds a different modulation scheme and coding rate, and Viterbi-decodes a data sequence transmitted by being convolutionally encoded by one convolutional encoder continuously. An error correction circuit, wherein when a signal to be converted into demodulated I / Q data corresponding to a fixed symbol is a symbol coordinate conversion signal, the input symbol is fixed for an input section of a fixed symbol sequence according to the symbol coordinate conversion signal. An input symbol conversion circuit that changes the code point of the symbol sequence and outputs the input symbol without changing it except for the section of the fixed symbol sequence. A Viterbi decoder that performs Viterbi decoding corresponding to a modulation scheme and a coding rate of each symbol output from the input symbol conversion circuit according to a known modulation scheme / coding rate information between transmission and reception, and an input to the Viterbi decoder. The modulation scheme / coding rate information of each symbol to be provided to the Viterbi decoder, and when the modulation scheme and coding rate are switched, a fixed symbol sequence for termination is included following the last symbol before switching. In
An error correction circuit, comprising: a Viterbi decoder control circuit that generates the symbol coordinate conversion signal and supplies the symbol coordinate conversion signal to the input symbol conversion circuit. 18. A transmission frame is composed of symbols of a plurality of modulation schemes and a plurality of coding rates, and when a modulation scheme and a coding rate are switched, a fixed symbol sequence for termination follows the last symbol before the switching. In some cases,
Information about the modulation scheme / coding rate of each symbol is included as transmission control information for each frame, and the symbols of each frame exceed the different modulation schemes and coding rates, and are continuously 1 bit.
An error correction circuit for performing Viterbi decoding of a data sequence convoluted and transmitted by two convolutional encoders, wherein a signal to be converted into demodulated I / Q data corresponding to a fixed symbol is a symbol coordinate conversion signal. According to the symbol coordinate conversion signal, for an input section of a fixed symbol sequence, an input symbol is changed to a code point of the fixed symbol series, and for an area other than the section of the fixed symbol series, an input is output without changing the input symbol. A symbol conversion circuit, a Viterbi decoder that performs Viterbi decoding corresponding to a modulation scheme and a coding rate of each symbol output from the input symbol conversion circuit according to modulation scheme / coding rate information, A transmission control information decoding circuit for decoding transmission control information; and a decoding result output from the transmission control information decoding circuit. Thus, the modulation scheme / coding rate information of each symbol input to the Viterbi decoder is extracted and provided to the Viterbi decoder, and when the modulation scheme and coding rate are switched, the modulation scheme / coding rate is terminated following the last symbol before switching. And a Viterbi decoder control circuit that generates the symbol coordinate conversion signal when the fixed symbol sequence is included in the Viterbi decoder and supplies the generated signal to the Viterbi decoder. 19. The method according to claim 1, wherein the Viterbi decoder uses a fixed symbol sequence as a fixed branch signal when a signal specifying a branch in a state transition of a trellis diagram is a fixed branch signal. The Viterbi decoder control circuit is replaced by a configuration in which the fixed symbol sequence for termination follows the last symbol before switching at the time of switching the modulation method and the coding rate. If included, in the input fixed symbol sequence, from the first symbol to the symbol in which the state of the convolutional encoder is determined, of the branches output from each state in Viterbi decoding, The fixed branch signal for validating only one branch corresponding to the symbol sequence and invalidating the other branches is also used. 19. The error correction circuit according to claim 7, wherein the generation is added and replaced with a configuration provided to the Viterbi decoder. 20. When the Viterbi decoder uses a signal for reducing the number of states of a trellis diagram for a fixed symbol sequence as a state reduction signal, and when switching a modulation scheme and a coding rate, the state reduction signal is also used. The Viterbi decoder control circuit is replaced with a configuration that performs Viterbi decoding, and a fixed symbol sequence for termination is included after the last symbol before switching at the time of switching the modulation scheme and the coding rate. In the case, in the input fixed symbol sequence, from the first symbol to the symbol in which the state of the convolutional encoder is determined, out of all the states in Viterbi decoding, up to that symbol is input. Making only the corresponding state valid and disabling the other states to generate the state reduction signal for reducing the state each time one symbol is input. And a configuration provided to the Viterbi decoder is added.
19. The error correction circuit according to any one of items 3, 17, and 18. 21. The Viterbi decoder, wherein, for a fixed symbol sequence, a signal specifying a branch in a state transition of a trellis diagram is a fixed branch signal, and a signal for reducing the number of states in the trellis diagram is a state reduction signal. When the modulation scheme and the coding rate are switched, the configuration is replaced with a configuration for performing Viterbi decoding that additionally supports the fixed branch signal and the state reduction signal, and the Viterbi decoder control circuit is configured to perform modulation scheme and coding. At the time of rate switching, if a fixed symbol sequence for termination is included following the last symbol before switching, the state of the convolutional encoder from the first symbol in the input fixed symbol sequence is changed. Up to the determined symbol, one of the branches output from each state in the Viterbi decoding corresponds to one brand corresponding to the fixed symbol sequence. And the fixed branch signal for invalidating the other branches is generated, and among all the states in Viterbi decoding, only the state corresponding to the input of the symbol is made valid, and the other states are made valid. Is invalidated, the state reduction signal for reducing the state every time one symbol is input is generated, and in addition to the confirmed state signal,
19. The error correction circuit according to claim 7, wherein the error correction circuit is replaced with a configuration applied to the Viterbi decoder. 22. When the Viterbi decoder uses a signal for reducing the number of states of a trellis diagram for a fixed symbol sequence as a state reduction signal, and when switching a modulation scheme and a coding rate, the state reduction signal is also used. The Viterbi decoder control circuit is replaced with a configuration that performs Viterbi decoding, and a fixed symbol sequence for termination is included after the last symbol before switching at the time of switching the modulation scheme and the coding rate. In the case, in the input fixed symbol sequence, from the first symbol to the symbol in which the state of the convolutional encoder is determined, out of all the states in Viterbi decoding, up to that symbol is input. Reset to the minimum value that can take only the path metric of the corresponding state, to the maximum value that can take another state, and after it is determined to be one state, one state that has been determined A state reduction signal for resetting to a minimum value that can take only the path metric of the state and a maximum value that can take another state, and replacing it with a configuration that is provided to the Viterbi decoder. Claims 7, 8, 1
19. The error correction circuit according to any one of 0, 12, 13, 17, and 18. 23. The Viterbi decoder, wherein, for a fixed symbol sequence, a signal specifying a branch in a state transition of a trellis diagram is a fixed branch signal, and a signal for reducing the number of states in the trellis diagram is a state reduction signal. When the modulation scheme and the coding rate are switched, the configuration is replaced with a configuration for performing Viterbi decoding that additionally supports the fixed branch signal and the state reduction signal, and the Viterbi decoder control circuit is configured to perform modulation scheme and coding. At the time of rate switching, if a fixed symbol sequence for termination is included following the last symbol before switching, the state of the convolutional encoder from the first symbol in the input fixed symbol sequence is changed. Up to the determined symbol, one of the branches output from each state in the Viterbi decoding corresponds to one brand corresponding to the fixed symbol sequence. And the minimum value that can take only the path metric of the state corresponding to the input of the symbol among all the states in Viterbi decoding among the fixed branch signal for validating only the other branch and invalidating the other branches. To
To reset to the maximum value that can take another state, and after it is determined to be one state, to reset to the minimum value that can take only the path metric of the determined one state, and to the maximum value that can take another state The error correction according to any one of claims 7, 8, 10, 17, and 18, wherein the generation of the state reduction signal is also added and the configuration is applied to the Viterbi decoder. circuit. 24. In a transmission format, when a fixed-length data sequence of a minimum unit is a slot, and one frame is M slots and one superframe is N frames,
An error correction circuit for deinterleaving, on the receiving side, a data sequence transmitted by interleaving M slots with a depth of N for each slot in the superframe, and selecting one of the M slots of each frame. When a signal for deinterleaving only the selected L slot data is used as a slot selection signal, a deinterleave circuit for deinterleaving only the data of the L slot selected according to the slot selection signal and outputting the data. An error correction circuit, comprising: a channel selection circuit that generates the slot selection signal according to channel selection information and supplies the slot selection signal to the de-interleave circuit. 25. The de-interleaving circuit sets the maximum number of slots per frame to be selected to Lmax.
25. The error correction circuit according to claim 24, wherein two banks of an area corresponding to only the maximum (Lmax.times.N) slots of the memory circuit are used. 26. The deinterleaving circuit, wherein the selected and deinterleaved L slot data per frame is continuously output at a transmission format L / M speed. Item 25. The error correction circuit according to Item 24. 27. In a transmission system in which transmission is performed in a transmission format in which a plurality of MPEG transport streams are multiplexed, a data sequence of each packet unit of the MPEG transport stream is set as a slot, and one frame = M slot and one superframe. = N frames, the transport stream number information of each slot is included in the superframe as transmission control information, and in the superframe, M slots are interleaved with a depth of N for each slot and transmitted. An error correction circuit for deinterleaving a data sequence to be received on the receiving side, wherein a signal for deinterleaving only data of a selected L slot among M slots of each frame is used as a slot selection signal. When the slot selection A deinterleave circuit for deinterleaving only the data of the L slot selected according to the signal and outputting data, a transmission control information decoding circuit for decoding the transmission control information included in each frame, and a transmission control information decoding A channel selection circuit for decoding transport stream number information of each slot from a decoding result output from the circuit, generating the slot selection signal according to the channel selection information, and providing the slot selection signal to the de-interleave circuit. An error correction circuit characterized by the following. 28. The de-interleave circuit, assuming that the maximum number of slots per frame occupied by one type of transport stream is Lmax, an area including only the maximum (Lmax × N) slots of the memory circuit and two banks. 28. The error correction circuit according to claim 27, wherein the data is output by deinterleaving only one type of transport stream selected by using. 29. When the maximum number of slots per frame occupied by one type of transport stream is Lmax, and K is an integer of 2 or more, the de-interleave circuit has a maximum (Lmax × N × 28. The error correction circuit according to claim 27, wherein K) uses two regions of only the number of slots and deinterleaves the selected K or less types of transport streams and outputs data. 30. The deinterleaving circuit outputs L slot data per frame selected and deinterleaved continuously at a transmission format of L / M speed. Item 29. The error correction circuit according to Item 27. 31. The de-interleave circuit, if each of the selected J types of transport streams occupies L1, L2,..., Lj slots per frame, selects・ Total for each interleaved frame (L1 + L2 + ... +
Lj) The data of the slot is transferred to the transmission format (L1).
28. The error correction circuit according to claim 27, wherein the output is continuously performed at a rate of + L2 +... + Lj) / M. 32. In a transmission format, when a fixed-length data sequence of a minimum unit is a slot, and one frame is M slots and one superframe is N frames,
An error correction circuit for de-randomizing a data sequence transmitted by being continuously randomized in superframe units on the receiving side, wherein data of L slots already selected among M slots of each frame are provided. When a signal for performing de-randomization for each slot is used as a slot selection signal, there are (N × M) kinds of initial values of de-randomization for each head data of (N × M) slots in one superframe. And
When the data of the L slot already selected in accordance with the slot selection signal is input, the de-randomization for each input slot is performed from an initial value corresponding to each slot input in accordance with the slot selection signal. The randomizing circuit and the M / S slots of each frame which have already been selected and
A channel selection circuit that generates the slot selection signal for performing the de-randomization for each slot in accordance with the channel selection information for the data of the L slot input to the randomization circuit and provides the slot selection signal to the de-randomization circuit. An error correction circuit characterized in that: 33. In a transmission system in which transmission is performed in a transmission format in which a plurality of MPEG transport streams are multiplexed, a data sequence of each packet unit of the MPEG transport stream is a slot, and one frame = M slot, one superframe. = N frames, transport stream number information of each slot is included in the superframe as transmission control information, and a data sequence that is continuously randomized and transmitted in units of the superframe is An error correction circuit that performs de-randomization on the receiving side, wherein when a signal for performing de-randomization for each slot is used as a slot selection signal for data of an already selected L slot among M slots of each frame, (N × M) slot in one superframe Has initial values of (N × M) types of de-randomization for each head data of the set.
When the data of the L slot already selected according to the slot selection signal is input, the data for performing the de-randomization for each input slot is initialized from the initial value corresponding to each input slot according to the slot selection signal. A randomizing circuit, a transmission control information decoding circuit that decodes the transmission control information included in each frame, and a transport stream number information for each slot, which is decoded from a decoding result output from the transmission control information decoding circuit. For the data of the L slot which is already selected from the M slots of each frame and inputted to the de-randomizing circuit, the slot selecting signal for performing the de-randomizing for each slot is generated according to the tuning information. , A tuning circuit provided to the de-randomizing circuit. Positive circuit. 34. In a transmission format, when a fixed-length data sequence of a minimum unit is a slot, and one frame is M slots and one superframe is N frames,
An error correction circuit for outputting only L-slot data per frame selected from a transmitted data sequence on the receiving side in accordance with channel selection information, wherein L-slot data selected from M slots in each frame is output. When a signal for continuously outputting at the L / M speed of the transmission format is used as the slot selection signal, only the data of the selected L slot is read and written to the memory circuit in accordance with the slot selection signal, so that the data is selected. A speed conversion circuit that continuously outputs L-slot data per frame at the L / M speed of the transmission format; and a L / M data of a selected L-slot among the M slots of each frame. Generating the slot selection signal for continuously outputting at the speed of M in accordance with tuning information; Error correction circuit, characterized by comprising: a channel selection circuit, a given to. 35. The speed conversion circuit, wherein the maximum number of slots per frame selected is Lmax
35. The error correction circuit according to claim 34, wherein an area corresponding to only a maximum of Lmax slots of said memory circuit is used. 36. In a transmission system for performing transmission in a transmission format in which a plurality of MPEG transport streams are multiplexed, a data sequence of each packet unit of the MPEG transport stream is set as a slot, and one frame = M slot, one superframe. = N frames, the transport stream number information of each slot is included in the superframe as transmission control information, and a data sequence to be transmitted is converted into L slots per frame selected according to channel selection information on the receiving side. An error correction circuit that outputs only data of a selected one of L slots out of M slots of each frame at a rate of L / M of a transmission format. Is selected according to the slot selection signal. A speed conversion circuit that continuously outputs L-slot data per selected frame at a rate of L / M in the transmission format by reading and writing only data in the L-slot to the memory circuit; A transmission control information decoding circuit for decoding the transmission control information; and a transport stream number information of each slot is decoded based on a decoding result output from the transmission control information decoding circuit. The slot selection signal for continuously outputting L slot data corresponding to the localized transport stream at the L / M speed of the transmission format is generated in accordance with tuning information, and is provided to the speed conversion circuit. An error correction circuit, comprising: a tuning circuit. 37. When the maximum number of slots per frame occupied by one type of transport stream is Lmax, the speed conversion circuit uses an area of only the maximum Lmax slots of the memory circuit, and 37. The error correction circuit according to claim 36, wherein one type of transport stream is output continuously. 38. The speed conversion circuit, if the maximum number of slots per frame occupied by one type of transport stream is Lmax and K is an integer of 2 or more, the maximum (Lmax × K 37. The error correction circuit according to claim 36, wherein a transport stream of not more than K types selected is continuously output using an area of only slots. 39. Assuming that the selected J types of transport streams occupy L1, L2,..., Lj slots per frame, respectively,・
The streams are respectively represented by the transmission formats L1 / M,
37. The error correction circuit according to claim 36, wherein the error correction circuit is replaced with a configuration in which outputs are continuously performed in parallel at a speed of L2 / M,..., Lj / M. 40. In addition to the de-interleave circuit and the channel selection circuit, the slot receives a data sequence of L slots per frame that has already been selected according to the slot selection signal, and outputs the slot output from the channel selection circuit. 26. The error correction circuit according to claim 24, further comprising a speed conversion circuit for continuously outputting a data sequence at a transmission format of L / M according to the selection information. 41. The speed conversion circuit, wherein the maximum number of slots per frame selected is Lmax
41. The error correction circuit according to claim 40, wherein an area of only the maximum Lmax slots of the memory circuit is used. 42. In addition to the de-interleave circuit, the transmission control information decoding circuit, and the channel selection circuit, a data sequence of L slots per frame, which has been selected according to the slot selection signal, is input. 30. A speed conversion circuit for continuously outputting a data sequence at a transmission format L / M speed in accordance with the slot selection information output from a station circuit. Error correction circuit described in the section. 43. When the maximum number of slots per frame occupied by one type of transport stream is Lmax, the speed conversion circuit selects a channel using only the area corresponding to the maximum Lmax slots of the memory circuit. 43. The error correction circuit according to claim 42, wherein the one type of transport stream is continuously output. 44. A maximum (Lmax × K) slot of a memory circuit, wherein the maximum number of slots per frame occupied by one type of transport stream is Lmax and K is an integer of 2 or more. 43. The error correction circuit according to claim 42, wherein a transport stream of not more than K types selected is continuously output using an area of only minutes. 45. The above-mentioned speed conversion circuit, wherein the selected J types of transport streams occupy L1, L2,..., Lj slots per frame, respectively.・
The streams are respectively represented by the transmission formats L1 / M,
43. The error correction circuit according to claim 42, wherein the error correction circuit is replaced with a configuration in which outputs are continuously performed in parallel at a speed of L2 / M,..., Lj / M.