JP7161531B2 - Receiving device, communication system, and receiving device control method - Google Patents

Description

The present technology relates to a receiver, a communication system, and a control method for the receiver. More specifically, the present invention relates to a receiver for receiving terrestrial digital television broadcasting, a communication system, and a control method for the receiver.

In recent years, the development of transmitters and receivers for providing next-generation terrestrial digital television broadcasting services inheriting the features of the ISDB-T (Integrated Services Digital Broadcasting-Terrestrial) system is underway. In the ISDB-T next-generation system, a transmitting device encodes content to be broadcast into a plurality of codewords using a Forward Error Correction (FEC) system. Then, the transmitting apparatus further divides the sequence of FEC blocks in which the codewords are carrier-modulated and arranged, stores them in a plurality of symbols, and transmits them in units of frames.

Here, in the ISDB-T next-generation system, from the viewpoint of improving transmission efficiency, the head of the FEC block within each symbol is allowed to deviate from the head of the symbol. Therefore, a transmission device has been proposed that stores a pointer indicating the head position of the first FEC block in the frame next to the current frame in the current frame and transmits the pointer (see, for example, Patent Document 1).

JP 2016-65627 A

In the conventional technology described above, the receiving device can obtain the head position of the FEC block in the next frame by referring to the pointer stored in the current frame, and start decoding the FEC block. However, a pointer to the beginning of the first FEC block in the current frame is stored in the frame before the current frame. For this reason, the receiving device cannot acquire the head position of the encoded block in the first received frame that does not have the previous frame, and cannot start decoding until the next frame. As described above, the above-described receiving apparatus cannot decode the first frame, and there is a problem that the timing of starting decoding is delayed with respect to the timing of receiving the first frame.

The present technology has been developed in view of such circumstances, and an object of the present technology is to shorten the delay time before decoding starts in a receiving device that receives and decodes frames.

The present technology has been made to solve the above-described problems, and a first aspect of the present technology includes a plurality of divided data obtained by dividing a block sequence in which a predetermined number of encoded blocks are arranged, and the plurality of divided data. a receiving unit for receiving a frame including a tail position of the last coded block in the last divided data of the above, and the coded block in a specific divided data among the plurality of divided data based on the tail position and a receiving device that acquires the starting position of the , and a control method thereof. This brings about the effect of extracting a coded block from a specific head position in the frame and starting decoding.

In the first aspect, the head position acquisition unit may calculate the head position from the size of the encoded block, a division unit that is a unit obtained by dividing the block sequence, and the tail position. This brings about the effect of obtaining the start position according to the size of the coding block and the division unit.

Moreover, this first aspect may further include a deinterleaver that deinterleaves the plurality of divided data. This brings about the effect of acquiring the data before interleaving.

In the first aspect, a demodulator that demodulates the frame and supplies identification information for identifying the specific divided data, and a delay unit that delays the identification information and supplies it to the head position acquisition unit. and the head position obtaining unit may obtain the head position of the divided data related to the identification information. This brings about an effect that the head position related to the delayed identification information is acquired.

In the first aspect, the transmission control signal processing unit acquires the tail position from a transmission control signal and supplies the tail position to the head position acquisition unit, and the frame stores the tail position. It may contain a control signal.

Further, in the first aspect, a coded block extracting unit extracting each of the coded blocks from the plurality of divided data based on the acquired head position; and decoding the extracted coded blocks. and a coded block decoding unit for decoding. This brings about the effect that the encoded block is decoded based on the starting position.

Further, according to a second aspect of the present technology, a plurality of divided data obtained by dividing a block sequence in which a predetermined number of coding blocks are arranged, and the end of the last coding block in the last divided data of the plurality of divided data a transmitting device that transmits a frame containing a position, a receiving unit that receives the frame, and a head position of the coded block in specific divided data among the plurality of divided data based on the end position. A communication system comprising: a receiving device comprising a head position acquisition unit; This brings about an effect that a frame is transmitted and received, a coded block is extracted from a specific head position in the frame, and decoding is started.

Advantageous Effects of Invention According to the present technology, a receiving device that receives and decodes a frame can have an excellent effect of being able to shorten the delay time until the start of decoding. Note that the effects described here are not necessarily limited, and may be any of the effects described in the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram which shows one structural example of the communication system in 1st Embodiment of this technique. FIG. 3 is a diagram for explaining a procedure up to OFDM (Orthogonal Frequency Division Multiplexing) frame generation in the first embodiment of the present technology; It is a figure which shows an example of the data structure of the TMCC carrier in 1st Embodiment of this technique. It is a figure which shows an example of the data structure of the OFDM frame in 1st Embodiment of this technique. 1 is a block diagram showing a configuration example of a receiving device according to a first embodiment of the present technology; FIG. 4 is a timing chart for explaining a pointer calculation method according to the first embodiment of the present technology; It is a flow chart which shows an example of operation of a transmission set in a 1st embodiment of this art. It is a flow chart which shows an example of operation of a receiving set in a 1st embodiment of this art. FIG. 7 is a diagram for explaining a procedure up to OFDM frame generation in the second embodiment of the present technology; It is a block diagram which shows one structural example of the decoding part in 2nd Embodiment of this technique. It is a flow chart which shows an example of operation of a receiving set in a 2nd embodiment of this art.

Hereinafter, a form for carrying out the present technology (hereinafter referred to as an embodiment) will be described. Explanation will be given in the following order.
1. First Embodiment (Example of back-calculating a specific pointer from the pointer of the next frame)
2. Second Embodiment (Example of performing deinterleave processing and back-calculating a specific pointer from the pointer of the next frame)

<1. First Embodiment>
[Configuration example of communication system]
FIG. 1 is a block diagram showing one configuration example of a communication system according to the first embodiment of the present technology. This communication system is for providing terrestrial digital television broadcasting services of the ISDB-T next-generation standard, and includes a transmitting device 100 and a receiving device 200 .

The transmitting device 100 has an antenna 101 . Transmitting apparatus 100 generates an OFDM frame modulated by orthogonal frequency division multiplexing, antenna 101 generates a radio signal superimposed on the frame, and radio-transmits to receiving apparatus 200 .

Receiving apparatus 200 includes antenna 201 , tuner 210 , AD (Analog to Digital) conversion section 220 and decoding section 230 .

Antenna 201 receives a radio signal from transmitting apparatus 100 and generates an analog signal. This antenna 201 supplies an analog signal to the tuner 210 . Note that the antenna 201 is an example of a receiving unit described in the claims.

The tuner 210 selects a signal of a predetermined channel in the signal from the antenna 201 and outputs it to the AD converter 220 via the signal line 219 .

The AD converter 220 converts the analog output signal from the tuner 210 into a digital signal. This digital signal contains OFDM frames. The AD converter 220 supplies the digital signal as a received signal to the decoder 230 via the signal line 229 .

The decoding unit 230 decodes the OFDM frame. The decoding unit 230 outputs the decoding result as decoded data.

FIG. 2 is a diagram for explaining the procedure up to OFDM frame generation in the first embodiment of the present technology. In the same figure, a indicates an example of an input data sequence, and b in the same figure indicates an example of an encoded sequence. c in the figure shows an example of a sequence of FEC blocks. Also, d in the figure indicates a symbol group in the OFDM frame.

When content to be broadcasted is input, transmitting device 100 divides the content into a plurality of input data of a certain size such as input data #1, #2 and #3, as illustrated in a in FIG. do.

Then, transmitting apparatus 100 performs Forward Error Correction (FEC) coding on each piece of input data. For example, in forward error correction coding, BCH coding and LDPC (Low-Density Parity-Check) coding are performed in order. By these encodings, a sequence of code words consisting of data and parity for correcting errors in the data is generated, as illustrated by b in FIG.

Transmitting apparatus 100 then performs carrier modulation and generates a plurality of FEC blocks such as FEC blocks #1, #2 and #3, as illustrated in c in FIG. This FEC block is a sequence of carrier-modulated codewords. The size of each FEC block is constant, and the size (here, the number of carriers) is m (m is an integer). Note that the FEC block is an example of the coding block described in the claims.

Transmitting apparatus 100 divides an FEC block sequence, in which a predetermined number of FEC blocks are arranged, into predetermined division units to generate a plurality of divided data. This division unit is set to the number of data carriers Ns (Ns is an integer) that can be stored in one symbol.

Then, transmitting apparatus 100 generates a transmission control signal (TMCC: Transmission and Multiplexing Configuration and Control), stores the TMCC and each of the divided data in a plurality of symbols, and transmits them as an OFDM frame. Each OFDM frame stores a certain number of symbols (for example, 204) as exemplified by d in FIG. Each symbol stores divided data and other data such as TMCC. Assuming that the number of symbols is "204", the number of data carriers in one symbol is Ns, so the total number of data carriers in one OFDM frame is Ns×204.

Here, in the ISDB-T next-generation standard, from the viewpoint of improving transmission efficiency, it is proposed that the FEC block size m is not limited to a divisor of the number of data carriers in the OFDM frame (Ns×204, etc.). ing. Therefore, if the size m does not correspond to a divisor of the total number of data carriers, the beginning of the OFDM frame will not coincide with the beginning of the first FEC block in the OFDM frame and will be shifted. Also, in each symbol, the head of the FEC block is shifted from the head of the symbol. Therefore, receiving apparatus 200 cannot extract the FEC block from the OFDM frame unless the shift (in other words, offset) is obtained. Information indicating the start position of the FEC block in each symbol is hereinafter referred to as "FEC block pointer". In the figure, P[s] indicates the FEC block pointer of the sth symbol (s is an integer).

Transmitter 100 stores, in each TMCC of an OFDM frame, an FEC block pointer indicating the start position of the first FEC block in the next OFDM frame. For example, with an OFDM frame as the current frame, the TMCC in the current frame stores the first FEC block pointer in the next OFDM frame. In the figure, P[0]_c indicates the first FEC block pointer in the current frame, and P[0]_n indicates the next first FEC block pointer of the current frame. P[0]_n is also the tail position of the last FEC block #N in the last divided data in the current frame.

FIG. 3 is a diagram illustrating an example of a data structure of a TMCC carrier according to the first embodiment of the present technology;

Transmitting apparatus 100 differential-set cyclic-encodes TMCC including the number of segments, modulation order, code length, and reserve area, and differential-modulates to generate a TMCC carrier.

Here, the modulation order represents the number of bits mapped to one symbol of the FEC block. Also, the code length indicates the code length of the codewords forming the FEC block.

The first FEC block pointer P[0]_n in the next frame is stored, for example, in a reserved area within the TMCC. Although the transmitting device 100 stores the FEC block pointer P[0]_n in the TMCC, it can also be stored in the header of the data frame instead of the TMCC. In this case, receiving device 200 may extract FEC block pointer P[0]_n from the header.

FIG. 4 is a diagram illustrating an example of the data structure of an OFDM frame according to the first embodiment of the present technology; The vertical axis in the figure is the time axis, and the horizontal axis is the frequency axis. This figure is described in STD-B31 "Terrestrial digital television broadcasting transmission system" of ARIB standard. The example in the figure is an example when QAM (Quadrature Amplitude Modulation) modulation is adopted as the modulation method.

Numbers on the time axis are symbol numbers for identifying symbols. For example, if 204 symbols are stored in one OFDM frame, symbol numbers '0' to '203' are assigned. Also, the numbers on the frequency axis are carrier numbers for identifying carriers. In addition, the symbol number is an example of the identification information described in the claims.

As shown in the figure, one carrier in one OFDM frame is used for TMCC transmission. Also, an SP (Scattered Pilot) signal is inserted at a predetermined position. Also, in an OFDM frame, Ns data carriers are stored for each symbol. The data consisting of the Ns data carriers corresponds to the aforementioned "divided data".

[Configuration example of receiving device]
FIG. 5 is a block diagram showing a configuration example of the receiving device 200 according to the first embodiment of the present technology. Decoding section 230 in receiving apparatus 200 includes OFDM demodulation section 231 , transmission control signal demodulation decoding section 232 , FEC block pointer calculation section 233 , FEC block extraction section 234 and FEC block demodulation decoding section 235 .

The OFDM demodulator 231 demodulates the OFDM frame. The OFDM demodulation unit 231 performs OFDM demodulation such as fast Fourier transform and equalization processing on the received signal from the AD conversion unit 220, and separates it into a TMCC carrier and a data carrier that is a payload. The OFDM demodulator 231 supplies the TMCC carrier to the transmission control signal demodulator/decoder 232 and supplies the data carrier to the FEC block extractor 234 . The OFDM demodulator 231 also supplies the OFDM symbol start, which is information indicating the leading carrier in each symbol, to the FEC block extractor 234 . The OFDM demodulator 231 is an example of the demodulator described in the claims.

The OFDM demodulator 231 also receives a TMCC acquisition flag F_tmcc when the transmission control signal demodulator decoder 232 successfully decodes and acquires the TMCC. Since ISDB-T defines a method of arranging TMCC carriers within a frame, the OFDM demodulator 231 synchronizes the OFDM frame with the TMCC acquisition flag F_tmcc. In addition, since the SP signal is arranged with periodicity in the OFDM symbol direction, the OFDM demodulation unit 231 performs equalization processing using the SP as necessary after synchronizing with the successful decoding of the TMCC carrier. I do. Since it is necessary to specify the arrangement of SP signals in order to separate the data carriers of the payload, the data carriers are output to the FEC block extraction unit 234 after the TMCC acquisition flag F_tmcc is generated.

The OFDM demodulator 231 also identifies the symbol number s indicating the symbol when the TMCC acquisition flag F_tmcc is input, and supplies it to the FEC block pointer calculator 233 .

The transmission control signal demodulator/decoder 232 demodulates and decodes the TMCC carrier. For example, in ISDB-T, a synchronization word and a difference-set cyclic-encoded transmission control signal are differentially modulated and transmitted. Therefore, the transmission control signal demodulator/decoder 232 performs differential demodulation of the TMCC carrier, confirmation of matching with the synchronization word, decoding of the difference set cyclic code, and the like. Through these processes, the transmission control signal demodulator/decoder 232 obtains P[0]_n indicating the first FEC block pointer in the next OFDM frame, in addition to transmission parameters such as modulation order and code length. Further, the transmission control signal demodulation/decoding unit 232 interprets the TMCC, acquires the number of data carriers in the symbol Ns and the FEC block size m, 233. Note that in the ISDB-T standard, the FFT (Fast Fourier Transform) size is not included in the TMCC and must be estimated on the receiving side. The transmission control signal demodulator/decoder 232 acquires the number of data carriers Ns using the FFT size as well, if necessary.

Further, the transmission control signal demodulator/decoder 232 generates a TMCC acquisition flag F_tmcc and supplies it to the OFEM demodulator 231 and the FEC block pointer calculator 233 when the TMCC carrier is successfully decoded. The transmission control signal demodulator/decoder 232 is an example of the transmission control signal processor described in the claims.

The FEC block pointer calculator 233 acquires the FEC block pointer corresponding to a specific symbol in the current frame based on the FEC block pointer P[0]_n when the TMCC acquisition flag F_tmcc is input. . Note that the FEC block pointer calculation unit 233 is an example of the head position acquisition unit described in the claims.

The number of data carriers Ns in the OFDM frame and the size m of the FEC block are uniquely determined by the transmission parameters in the TMCC. Therefore, the FEC block pointer for a particular symbol in the current frame can be back calculated from the first FEC block pointer P[0]_n of the next OFDM frame, the size m and the number of data carriers Ns. For example, the FEC block pointer calculator 233 sets a variable k (k is an integer) from the symbol number s from the OFDM demodulator 231 according to the following equation.
k=S−s+1 Formula 1
In the above equation, S is the maximum value of the symbol number in the OFDM frame (such as "203"). For example, when the maximum value S is "203" and the symbol number s to be calculated is "200", the variable k is set to "4" from the above equation.

Then, the FEC block pointer calculator 233 sets the initial value “1” to the variable i, and calculates the FEC block pointer P[−i] by the following equation.
P[-i]=(P[-i+1]+Ns) mod m Equation 2
In the above expression, "mod" is a function that returns the remainder obtained by dividing the immediately preceding value by the immediately succeeding value.

The FEC block pointer calculation unit 233 increments the variable i and executes the calculation exemplified in Equation 2 again. The increment of variable i and the operation of Equation 2 are repeatedly performed until variable i becomes equal to variable k.

For example, when the variable k is set to "4" by Equation 1, the FEC block pointer calculator 233 first initializes the variable i to "1" and substitutes the initial value into Equation 2. P[-1] is calculated by the following formula.
P[−1]=(P[0]+Ns) mod m Equation 3
In the above equation, the first FEC block pointer P[0]_n of the next frame obtained by the transmission control signal demodulator/decoder 232 is substituted for P[0].

Subsequently, the FEC block pointer calculator 233 increments the variable i and calculates P[-2] by the following formula.
P[-2]=(P[-1]+Ns) mod m Equation 4
In the above equation, the value calculated by Equation 3 is substituted for P[-1].

Next, the FEC block pointer calculator 233 increments the variable i and calculates P[-3] by the following formula.
P[−3]=(P[−2]+Ns) mod m Equation 5
In the above equation, the value calculated by Equation 4 is substituted for P[-2].

Finally, the FEC block pointer calculator 233 increments the variable i and calculates P[-4] by the following equation.
P[−4]=(P[−3]+Ns) mod m Equation 6
In the above equation, the value calculated by Equation 6 is substituted for P[-3].

As illustrated in Equations 3 to 6, the FEC block pointer calculation unit 233 back-calculates the FEC block pointer P[−k] (P[−4], etc.) of a specific symbol from the FEC block pointer P[0]. can do.

The FEC block pointer calculator 233 supplies the calculated FEC block pointer P[−k] to the FEC block extractor 234 .

The FEC block extraction unit 234 extracts FEC blocks using the calculated FEC block pointer P[-k]. This FEC block extraction unit 234 initializes a predetermined count value to "0" or the like when an OFDM symbol start is input, and counts up the count value each time a data carrier is input. Then, the FEC block extraction unit 234 ends counting when the count value becomes equal to the FEC block pointer [−k], and extracts m data carrier groups after the end of counting from the OFDM frame as FEC blocks. . After that, similarly, the process of extracting m data carrier groups as one FEC block is repeatedly executed. The FEC block extraction unit 234 supplies the extracted FEC blocks to the FEC block demodulation/decoding unit 235 . Note that the FEC block extractor 234 is an example of the encoding block extractor described in the claims.

The FEC block demodulator/decoder 235 demodulates and decodes FEC blocks. The FEC block demodulator/decoder 235 performs carrier demodulation and error correction code decoding on the extracted FEC blocks. Then, FEC block demodulation/decoding section 235 outputs decoded data indicating the decoding result. The FEC block demodulation/decoding unit 235 is an example of the coded block decoding unit described in the claims.

FIG. 6 is a timing chart for explaining a pointer calculation method according to the first embodiment of the present technology. In the figure, the portions with the same filled pattern indicate one FEC block.

From timing T10 to T20, receiver 200 receives the first OFDM frame #0. This OFDM frame #0 includes, for example, 204 symbols with symbol numbers “0” to “203”.

Receiving apparatus 200 starts decoding the TMCC carrier in OFDM frame #0 at timing T10, and completes the decoding and acquires the TMCC at timing T11 before the start of the next OFDM frame #1. Timing T<b>11 for acquiring TMCC depends on the performance of receiving apparatus 200 . The receiver 200 acquires the first FEC block pointer P[0]_n in the next OFDM frame #1 from the TMCC. The FEC block pointer P[0]_n is also the tail position of the last FEC block in the last segmented data in OFDM frame #0.

Assume that the symbol number of the first symbol after timing T11 is "200" and the FEC block pointer of that symbol is P[-4]. Receiving device 200 calculates FEC block pointer P[−1] of symbol number “203” by Equation 3. Receiving apparatus 200 then sequentially calculates FEC block pointers P[−2], P[−3] and P[−4] using Equations 4 to 6.

Receiving apparatus 200 uses the calculated FEC block pointer P[−4] to extract and decode the FEC block (the shaded portion) whose head is the pointer.

Now assume a comparative example in which the back calculation of the FEC block pointer P[-4] is not performed. Since only the FEC block P[0]_n of the next OFEM frame is stored in the TMCC, decoding of the FEC block cannot be started at timing T11 in the comparative example. In this case, the receiver needs to wait until the start timing T20 of the next OFDM frame to start decoding. Since the length of one OFDM frame is, for example, 400 milliseconds (ms), the start of decoding is delayed by 400 milliseconds (ms) with respect to the reception timing T10 of the first OFDM frame #0. . As a result, there is a delay of at least 400 milliseconds (m) until the television or the like outputs video and audio, which are broadcast contents.

On the other hand, the receiving device 200, which performs back calculation of the FEC block pointer P[-4], counts back the FEC block pointer P[-4] from the FEC block P[0]_n of the next OFEM frame. Therefore, receiving apparatus 200 can start decoding at timing T11 before timing T20. As a result, the delay time until decoding starts can be made shorter than in the comparative example.

[Example of operation of transmitter]
FIG. 7 is a flow chart showing an example of the operation of the transmitting device 100 according to the first embodiment of the present technology. This operation is initiated, for example, when a predetermined application for transmission is executed. Transmitting apparatus 100 performs carrier modulation such as QAM mapping on a codeword obtained by encoding input data, encodes it into FEC blocks (step S901), divides the sequence in which these blocks are arranged, and divides the data carrier into data carriers. Generate (step S902). Transmitter 100 then generates a TMCC carrier (step S903) and transmits an OFDM frame including the data carrier and the TMCC carrier (step S904). After step S904, transmitting apparatus 100 repeats step S901 and subsequent steps.

[Example of operation of receiving device]
FIG. 8 is a flow chart showing an example of the operation of the receiving device 200 according to the first embodiment of the present technology. This operation is started, for example, when a predetermined application for receiving is executed. The receiver 200 receives the OFDM frame (step S951) and extracts the TMCC carrier (step S952). Receiving apparatus 200 demodulates and decodes the TMCC carrier (step S953), and determines whether the decoding is successful (step S954). If the decoding fails (step S954: No), the receiving device 200 repeats step S951 and subsequent steps.

On the other hand, if the decoding is successful (step S954: Yes), the receiving device 200 calculates the FEC block pointer P[-k] while demodulating the data carrier (step S955).

Receiving apparatus 200 then extracts an FEC block using the calculated FEC block pointer P[−k] (step S956), and demodulates and decodes the FEC block (step S957). After step S957, receiving apparatus 200 repeatedly executes step S951 and subsequent steps.

In this way, according to the first embodiment of the present technology, the receiving device 200 calculates the FEC block pointer of the previous specific symbol from the FEC block pointer P[0], so that the Decoding of FEC blocks can start before reception. This makes it possible to shorten the delay time until the decoding starts compared to the case where the decoding of the FEC block is started after the reception of the next frame.

<2. Second Embodiment>
In the first embodiment described above, the communication system did not perform interleaving and deinterleaving, but in this configuration there is a risk that error correction capability will be insufficient when a burst error occurs. The communication system of the second embodiment differs from that of the first embodiment in that interleaving and deinterleaving are further performed.

FIG. 9 is a diagram for explaining a procedure up to OFDM frame generation in the second embodiment of the present technology. In the same figure, a indicates an example of an input data sequence, and b in the same figure indicates an example of an encoded sequence. In the figure, c indicates the sequence after interleaving. d in the figure indicates an example of a sequence of FEC blocks. Also, e in the figure indicates a symbol group in the OFDM frame.

The transmission device 100 divides the content into a plurality of pieces of input data, as illustrated by a in FIG. Transmitting apparatus 100 performs carrier modulation and generates a plurality of codewords as illustrated in b in FIG.

Then, transmitting apparatus 100 performs frequency interleaving and time interleaving to generate a rearranged bit string illustrated in c in FIG. Transmitting apparatus 100 generates a sequence of FEC blocks by QAM mapping, as exemplified by d in FIG. Further, transmitting apparatus 100 divides the sequence of FEC blocks to generate a plurality of divided data. Then, transmitting apparatus 100 stores the TMCC and each of the divided data in a plurality of symbols, as illustrated by e in the figure, and transmits them as an OFDM frame.

FIG. 10 is a block diagram showing a configuration example of the decoding unit 230 according to the second embodiment of the present technology. Decoding section 230 of the second embodiment differs from that of the first embodiment in that it further includes frequency deinterleaver 236 , time deinterleaver 237 , delay section 238 and delay section 239 .

The OFDM demodulator 231 of the second embodiment supplies the symbol number s of the symbol to be calculated to the delay unit 238 and supplies the data carrier and OFDM symbol start to the frequency deinterleaver 236 .

The frequency deinterleaver 236 performs frequency deinterleaving on the data carriers. This frequency deinterleaver 236 supplies the deinterleaved data carrier to the time deinterleaver 237 together with the OFDM symbol start.

The time deinterleaver 237 performs time deinterleaving on the data carrier. This time deinterleaver 237 supplies the deinterleaved data carrier to the FEC block extraction unit 234 together with the OFDM symbol start.

The delay section 238 delays the symbol number s according to the processing time of the frequency deinterleaver 236 and outputs it to the delay section 239 .

The delay unit 239 delays the symbol number s according to the processing time of the time deinterleaver 237 and outputs it to the FEC block pointer calculation unit 233 .

FIG. 11 is a flow chart showing an example of the operation of the receiving device 200 according to the second embodiment of the present technology. The operation of the receiver 200 of the second embodiment differs from that of the first embodiment in that steps S961 to S964 are executed instead of step S955.

If the decoding of the TMCC carrier is successful (step S954: Yes), the receiving apparatus 200 demodulates the data carrier (step S961), and delays the symbol number while performing frequency deinterleaving (step S962). Then, receiving apparatus 200 delays the symbol number while performing time deinterleaving (step S963). Receiving apparatus 200 calculates the FEC block pointer corresponding to the delayed symbol number (step S964), and executes step S956 and subsequent steps.

Thus, according to the second embodiment of the present technology, transmitting apparatus 100 and receiving apparatus 200 perform interleaving and de-interleaving, and thus can improve resistance to burst errors.

In addition, the above-described embodiment shows an example for embodying the present technology, and the matters in the embodiment and the matters specifying the invention in the scope of claims have corresponding relationships. Similarly, the matters specifying the invention in the scope of claims and the matters in the embodiments of the present technology with the same names have corresponding relationships. However, the present technology is not limited to the embodiments, and can be embodied by various modifications to the embodiments without departing from the scope of the present technology.

In addition, the processing procedure described in the above embodiment may be regarded as a method having a series of procedures, and a program for causing a computer to execute the series of procedures or a recording medium for storing the program You can catch it. As this recording medium, for example, CD (Compact Disc), MD (MiniDisc), DVD (Digital Versatile Disc), memory card, Blu-ray disc (Blu-ray (registered trademark) Disc), etc. can be used.

It should be noted that the effects described in this specification are only examples and are not limited, and other effects may be provided.

Note that the present technology can also have the following configuration.
(1) Reception for receiving a frame including a plurality of divided data obtained by dividing a block sequence in which a predetermined number of encoded blocks are arranged and the end position of the last encoded block in the last divided data of the plurality of divided data Department and
a start position acquisition unit that acquires the start position of the encoded block in specific divided data among the plurality of divided data based on the end position.
(2) The receiving device according to (1), wherein the start position acquisition unit calculates the start position from the size of the encoded block, a division unit that is a unit into which the block sequence is divided, and the end position.
(3) The receiving apparatus according to (1) or (2), further comprising a deinterleaver that deinterleaves the plurality of divided data.
(4) a demodulator that demodulates the frame and supplies identification information for identifying the specific divided data;
a delay unit that delays the identification information and supplies it to the head position acquisition unit;
The receiving device according to (3), wherein the head position acquiring unit acquires the head position of the divided data related to the identification information.
(5) further comprising a transmission control signal processing unit that acquires the trailing position from the transmission control signal and supplies the trailing position to the leading position acquiring unit;
The receiver according to any one of (1) to (4), wherein the frame includes the transmission control signal storing the tail position.
(6) a coded block extraction unit that extracts each of the coded blocks from the plurality of divided data based on the acquired head position;
The receiving device according to any one of (1) to (5), further comprising an encoded block decoding unit that decodes the extracted encoded block.
(7) Transmitting a frame including a plurality of divided data obtained by dividing a block sequence in which a predetermined number of encoded blocks are arranged and the end position of the last coded block in the last divided data of the plurality of divided data. a transmitting device;
a receiving unit that receives the frame; and a start position obtaining unit that obtains the start position of the encoded block in specific divided data among the plurality of divided data based on the end position. communication system.
(8) Receive a frame containing a plurality of divided data obtained by dividing a block sequence in which a predetermined number of coded blocks are arranged and the end position of the last coded block in the last divided data of the plurality of divided data. a receiving procedure;
A control method for a receiving apparatus, comprising: a starting position obtaining procedure for obtaining a starting position of the encoded block in specific divided data among the plurality of divided data based on the ending position.

100 transmitter 101, 201 antenna 200 receiver 210 tuner 220 AD converter 230 decoder 231 OFDM demodulator 232 transmission control signal demodulator decoder 233 FEC block pointer calculator 234 FEC block extractor 235 FEC block demodulator decoder 236 frequency decoder interleaver 237 time deinterleaver 238, 239 delay unit

Claims (8)

a receiving unit for receiving a frame including a plurality of divided data obtained by dividing a block sequence in which a predetermined number of coded blocks are arranged and the end position of the last coded block in the last divided data of the plurality of divided data; ,
a start position acquisition unit that acquires the start position of the encoded block in specific divided data among the plurality of divided data based on the end position. 2. The receiving apparatus according to claim 1, wherein the head position acquiring unit calculates the head position from the size of the encoded block, a division unit that is a unit obtained by dividing the block sequence, and the tail position. 2. The receiving apparatus according to claim 1, further comprising a deinterleaver that deinterleaves the plurality of divided data. a demodulator that demodulates the frame and supplies identification information for identifying the specific divided data;
a delay unit that delays the identification information and supplies it to the head position acquisition unit;
4. The receiving device according to claim 3, wherein the head position acquiring unit acquires the head position of the divided data related to the identification information. further comprising a transmission control signal processing unit that acquires the trailing position from a transmission control signal and supplies the trailing position to the leading position acquiring unit;
2. The receiving apparatus according to claim 1, wherein said frame includes said transmission control signal storing said end position. a coded block extracting unit that extracts each of the coded blocks from the plurality of divided data based on the acquired head position;
2. The receiving apparatus according to claim 1, further comprising a coded block decoding unit that decodes the extracted coded block. a transmission device for transmitting a frame including a plurality of divided data obtained by dividing a block sequence in which a predetermined number of coded blocks are arranged and the tail position of the last coded block in the last divided data of the plurality of divided data; ,
a receiving unit that receives the frame; and a start position obtaining unit that obtains the start position of the encoded block in specific divided data among the plurality of divided data based on the end position. communication system. a receiving step of receiving a frame including a plurality of divided data obtained by dividing a block sequence in which a predetermined number of coded blocks are arranged and the tail position of the last coded block in the last divided data of the plurality of divided data; ,
A control method for a receiving apparatus, comprising: a starting position obtaining procedure for obtaining a starting position of the encoded block in specific divided data among the plurality of divided data based on the ending position.

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