JP2001054113A - Data transmission method and data transmitter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely reproduce an SDTI signal at a receiver side in a comparatively easy way by multiplexing a plurality of STDI signals, applying transmission rate conversion processing to 20-bit word stream data, inserting attached word data group to the stream data at a prescribed word interval to convert the resulting stream data into serial data and transmitting the serial data. SOLUTION: A composite data generating section 12 supplies 20-bit word stream data DM 20 to a speed conversion data insert section 13. Furthermore, a word data transmission section 14 supplies attached word data group DWT consisting of a plurality of 20-bit word data including 20-bit word synchronous data to which a predetermined code is assigned to the data insert section 13. Then the insertion section 13 coverts a word transmission rate, inserts attached word data group DWT from the word data transmission section 14 at a prescribed word interval, a PS conversion section 21 converts the resulting data into serial data and gives the converted data to a transmission section 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The invention described in the claims of the present application performs a multiplexing process on a plurality of digital signals to obtain 20-bit word string data, and adds a word to the obtained 20-bit word string data. The present invention relates to a data transmission method for forming composite 20-bit word string data by inserting an additional word data group including synchronization data, and transmitting the composite 20-bit word string data for transmission, and a data transmission apparatus provided for implementing the method. .

[0002]

2. Description of the Related Art In the field of transmission of digital data containing information data representing various kinds of signal information such as image information, the digital data is converted into serial data, an electric signal based on the serial data is obtained, and the signal is coaxial. A system for transmitting data through a transmission line formed using a cable or twisted pair line,
Alternatively, digital data is converted into serial data, and the serial data is converted into an optical signal, and the optical
A system for transmitting data through a transmission line formed using fibers has been put to practical use.

On the other hand, digital data representing image information, that is, image information data usually has an enormous amount of data. For example, when the data is transmitted or recorded, the quality of the data is substantially reduced. It is desired that the data is compressed so that the data amount can be reduced without lowering the data amount. Therefore, various researches and developments have been made on data compression techniques for reducing the amount of image information data. One of the results is digital data representing image information, especially moving image information. Regarding data compression for image information data that is
Moving Picture Experts Group (MPEG), a working group under the Technical Committee under the International Standards Organization
A standard system called MPEG, which has been examined and approved as a standard, has been proposed.

In the standard system called MPEG, image information data is subjected to data compression by high-efficiency coding.
When data compression by high-efficiency encoding according to EG is performed, data compression with an extremely high compression rate can be realized.
In addition, there is an advantage that an image reproduced based on the image information data subjected to the data compression can be of high quality. Therefore, in the field of business or home electronic devices such as digital video cameras and digital video tape recorders, image information data (M
PEG image information data) tends to increase.

In transmitting compressed digital video data such as MPEG image information data, and compressed digital video and audio data obtained by adding audio data to the digital video data as serial data through a transmission path. As an interface developed to be used, SDTI (Serial Data Transport
Interface) has been proposed. This SD
TI is the US SMPTE (Society of Motion Pictur)
e and Television Engineers), which is standardized as "SMPTE 305M".

A signal format under the SDTI (SDTI signal format) is, for example, as shown in FIG. FIG. 10A shows one line period in the SDTI signal format when the bit transmission rate when serialized is 270 Mbps, and forms 10-bit word string data in which one word is composed of 10 bits. are doing. Then, one frame period is formed by, for example, 525 line periods formed by connecting 525 lines.

In one line period shown in FIG. 10A, timing reference code data: EAV (End of
Active Video) and ancillary data (Ancillar
y Data) section and timing reference code data: SAV (S
tart of Active Video), followed by the payload section. EAV and SAV, respectively,
Four words (3FF, 000,000, XYZ; hexadecimal notation (the same applies hereinafter)) having the same word structure and each having a 10-bit structure are sequentially arranged. The auxiliary data section includes header data. In the payload part, user data and an error detection code: CR
C is arranged.

The header data included in the auxiliary data portion includes, for example, EAV as shown in FIG.
, An auxiliary signal flag consisting of three words (000, 3FF, 3FF): ADF, followed by data identification: DID, second data identification: SDID, data count: DC, line number: LN0, line number : LN
1, line number error detection code: LNCRC0, line number error detection code: LNCRC1, code and authorized address identification: C & AAI, 16 word destination address, 16 word source address, block type: BT, payload error detection code flag: CRCFL, spare data for header extension: RSV0 to RSV4, header error detection code: HDCRC0, header error detection code: HDCRC1,
Check sum: CS is sequentially arranged. Such header data is composed of a total of 53 words.

An SDT used for transmitting compressed digital video data or video and audio data.
A digital signal formed in accordance with the I signal format (hereinafter referred to as an SDTI signal) is converted from parallel data to serial data, and is usually subjected to scrambling and transmitted in the form of a transmission signal that is converted into an electric signal or an optical signal. Is done.

In the scrambling process in this case, the serial data to be processed is represented by a polynomial, and the serial data is sequentially divided by a primitive polynomial, for example, a ninth-order primitive polynomial: X ⁹ + X ⁴ +1. The quotient resulting from the operation is obtained as transmission data, and the mark ratio of transmission data (the ratio between "0" and "1") is statistically reduced to 1/2 on average, and the transmission data is primitive polynomial. Is a process that has been performed by the encryption. In actual transmission of transmission data, for example, instead of directly transmitting a quotient obtained by division by a ninth-order primitive polynomial: X ⁹ + X ⁴ +1, the quotient is further divided by an expression: X + 1. The transmission data is data (polarity-free data) in which it and the inverted data have the same information.

On the receiving side receiving the transmission data, the received transmission data is multiplied by the equation: X + 1, and further, is multiplied by a ninth-order primitive polynomial: X ⁹ + X ⁴ +1 to perform a descrambling process. Plays back serial data.

[0012]

SUMMARY OF THE INVENTION As described above, the SDT
Regarding the I signal, upon transmission through the transmission line after being converted into serial data, not only a single SDTI signal but also a plurality of SDTI signals are multiplexed and transmitted so that they can be reliably reproduced on the receiving side. If you can,
The efficient use of the SDTI signal is achieved,
The use range of the TI signal is expanded. And
Efficient use of the SDTI signal or expansion of the use range of the SDTI signal, for example, will result in further development of technology in the field of business or home electronic devices.
Therefore, from such a viewpoint, it is desired to provide a method capable of multiplexing and transmitting a plurality of SDTI signals so that the plurality of SDTI signals can be reliably reproduced on the receiving side by means that can be prepared relatively easily.

However, conventionally, SDTI
There is no concrete example of a transmission system capable of multiplexing and transmitting a plurality of signals so that the signals can be reliably reproduced on the receiving side. Further, there is no literature describing a technique relating to a transmission system capable of multiplexing and transmitting such a plurality of SDTI signals so as to be surely reproduced on a receiving side.

[0014] In view of the above, the invention described in the claims of the present application is designed so that a plurality of SDTI signals can be reliably reproduced on the receiving side by means capable of relatively easily preparing the SDTI signals. A data transmission method capable of multiplexing and transmitting the data and a data transmission apparatus provided for the implementation.

[0015]

A data transmission method according to the invention described in any one of claims 1 to 6 in the claims of the present application performs a multiplexing process on a plurality of SDTI signals. A 20-bit word string data is formed. The 20-bit word string data is subjected to transmission rate conversion processing, and includes a 20-bit word synchronization data provided with a predetermined code at a predetermined word interval. An additional word data group is inserted to form composite 20-bit word string data, the composite 20-bit word string data is converted to serial data, and the serial data is transmitted for transmission.

In particular, in the data transmission method according to the invention described in claim 2 of the present application, the additional word data group includes a plurality of 20-bit word data to which a predetermined code is assigned. Are selected as those containing 20 bits word synchronization data.

According to a seventh aspect of the present invention, there is provided a data transmission apparatus which performs a multiplexing process on a plurality of SDTI signals to form a 20-bit word string data. 2 obtained from the data forming means and the 20-bit word string data forming means.
A transmission rate conversion process is performed on the 0-bit word string data, and an additional word data group including 20-bit word synchronization data to which a predetermined code is given is inserted at a predetermined word interval. Composite data forming means for forming 20-bit word string data, and data transmitting means for converting composite 20-bit word string data obtained from the composite data forming means into serial data and transmitting the serial data for transmission It is composed.

In the data transmission method according to any one of the first to sixth aspects of the present invention, the data is transmitted after being converted into serial data. Multiple SDTIs to be sent
The composite 20-bit word string data based on the signal includes 20-bit word synchronization data to which a predetermined code is given. Such 20-bit word synchronization data is, for example, a plurality of 20-bit words to which a predetermined code is assigned, as in the data transmission method according to the invention described in claim 2 of the present application. Data is selected to be continuous with a specific sequence. Then, given a predetermined code, the 20-bit word synchronization data included in the composite 20-bit word string data is the composite 20-bit synchronization data including the same.
On the receiving side receiving the serial data based on the bit word string data, a plurality of SD
It is assumed that the word synchronization data required for the process for reproducing the TI signal is properly detected. Therefore, on the receiving side, the received composite 2
A state in which the data synchronization state required for the reproduction processing of the plurality of SDTI signals based on the 0-bit word string data is reliably obtained is secured.

In the data transmission method according to any one of the first to sixth aspects of the present invention, a predetermined code is provided. Conversion of composite 20-bit word string data to which bit word synchronization data is added into serial data, transmission of the converted serial data, and
Receiving the serial data and converting the received serial data into composite 20-bit word string data on the receiving side can be performed, for example, by transmitting and receiving a digital video signal under an HDTV system (high definition television system). This can be performed by using the transmission circuit device used for the above. Therefore, according to the data transmission method according to the invention described in any one of claims 1 to 6 in the claims of the present application, the SDTI signal is provided with a means that can be prepared relatively easily. A plurality can be multiplexed and transmitted so as to be surely reproduced on the receiving side.

Further, in the data transmission apparatus according to the invention described in claim 7 of the present application, a plurality of SDTIs which are transmitted to be converted into serial data and transmitted by the data transmitting means. The composite 20-bit word string data based on the signal includes 20-bit word synchronization data provided with a predetermined code, and the 20-bit word synchronization data includes:
For example, a plurality of 20-bit word data to which a predetermined code is assigned is selected to be continuous with a specific arrangement. Then, the 20-bit word synchronization data given the predetermined code and included in the composite 20-bit word string data is received by the receiving side that receives serial data based on the composite 20-bit word string data including the same. It is to be properly detected as word synchronization data required for processing for reproducing a plurality of SDTI signals from the composite 20-bit word string data obtained based on the serial data obtained, On the receiving side, a state in which the data synchronization state required for the reproduction processing of a plurality of SDTI signals based on the received composite 20-bit word string data is reliably obtained.

According to such a data transmission apparatus according to the invention described in claim 7 of the present application, a composite in which 20-bit word synchronous data to which a predetermined code is given is added is added. The conversion of the 20-bit word string data into serial data, the transmission of the converted serial data, and the reception side receiving the serial data, converting the received serial data into composite 20-bit word string data, For example, it is possible to use a transmission circuit device used for transmission and reception of a digital video signal under an HDTV system. Can be multiplexed and transmitted so as to be surely reproduced on the receiving side.

[0022]

FIG. 1 shows an embodiment of a data transmission method according to the present invention described in claims 1, 2, 3 or 6 of the present invention. 7 shows an example of a data transmission device according to the invention described in claim 7 of the present invention.

In the example shown in FIG.
SDTI signal DTI1, DTIS2, D of channel
TIS3, DTIS4, and DTIS5 are supplied to the 20-bit word string data forming unit 11. Each of the five-channel SDTI signals DTIS1 to DTIS5 is shown in FIG.
As shown in A and B, a 10-bit quantized digital signal which is a 10-bit word string data formed in accordance with the SDTI signal format is converted into serial data and scrambled. It is serial data having a bit transmission rate of, for example, 270 Mbps, and is bit-synchronized with each other.

In the 20-bit word string data forming unit 11, SDTI signals DTI1 to DT of five channels are provided.
The IS5 is subjected to a multiplexing process of sequentially extracting and multiplexing, for example, 10 bits from each of them, to obtain 20-bit word string data DM (20) having a word transmission rate of, for example, 67.5 MBps. . And 20
The 20-bit word string data DM (20) obtained from the bit word string data forming unit 11 is
2 is supplied.

In the composite data forming unit 12, the 20-bit word string data DM (20) is supplied to the speed conversion / data insertion unit 13. In addition, the speed conversion / data insertion unit 13 receives, from the word data transmission unit 14, additional word data composed of a plurality of 20-bit word data including 20-bit word synchronization data to which a predetermined code has been assigned. A group DWT is provided.

In the speed conversion / data insertion unit 13, the word transmission rate is set to 67.5 MBps.
For the 0-bit word string data DM (20), the word transmission rate is, for example, from 67.5 MBps to 7
While performing speed conversion to convert to 4.25 MBps,
At a predetermined word interval, an additional word data group DWT including the 20-bit word synchronization data from the word data transmission unit 14 is inserted, and thereby, the word transmission rate based on the 5-channel SDTI signals DTIS1 to DTIS5 is reduced. For example, composite 20-bit word string data DZ (20) of 74.25 MBps is formed.

FIG. 2 shows a specific configuration example of the speed conversion / data insertion unit 13. In the example shown in FIG. 2, SDTI signals DTI1 to DTI of five channels are provided.
The 20-bit word string data DM (20) based on S5 is supplied to the switch 15. The switch 15 performs switching every predetermined period, for example, every 1 ms in response to the control signal CSA from the switch control signal forming unit 16, thereby changing the 20-bit word string data DM (20) to 1
The data is alternately supplied to the memory unit 17 and the memory unit 18 every ms and the distribution of the 20-bit word string data DM (20) to the memory unit 17 and the memory unit 18 is performed.

A memory control signal forming unit 19 is provided in association with the memory unit 17 and the memory unit 18.
The memory control signal forming unit 19 is supplied with, for example, a clock signal CA having a frequency of 270 MHz synchronized with the clock signal in each of the five channels of the SDTI signals DTI1 to DTIS5 and a clock signal CB having a frequency of 74.25 MHz. Is done. Then, the memory control signal forming section 19 generates a write control signal QW having a frequency of 270 MHz / 4 = 67.5 MHz based on the clock signal CA, and sets a frequency of 74.70 MHz based on the clock signal CB. Read control signal Q at 25 MHz
R is generated, and the write control signal QW and the read control signal QR are supplied to both the memory unit 17 and the memory unit 18.

As a result, in the memory section 17, the 20-bit word string data DM (2
0) is supplied, the word transmission rate of the 20-bit word string data DM (20) is changed to 67.5 M in response to the write control signal QW having a frequency of 67.5 MHz.
It is written in the state of Bps. Also, the memory unit 18
Also, in the period in which the 20-bit word string data DM (20) is supplied through the switch 15, the frequency of the 20-bit word string data DM (20) is 67.5.
In response to the write control signal QW of MHz, the data is written in a state where the word transmission speed is 67.5 MBps. Therefore, 20 in each of the memory unit 17 and the memory unit 18
When the word transmission speed of the bit word string data DM (20) is set to 67.5 MBps, writing to the switch 1 is performed.
5 are alternately performed for 1 ms in accordance with the switching every 1 ms.

The 20-bit word string data DM (20) written to the memory unit 17 for 1 ms is supplied with a read control signal QR having a frequency of 74.25 MHz during the next 1 ms. , Word transmission rate 74.2
20-bit word string data DM '(2
0) from the memory unit 17 and the switch 20
Supplied to The 20-bit word string data DM (20) written in the memory unit 18 for 1 ms
Also, within the next 1 ms, the frequency is set to 74.25M.
In response to the read control signal QR at Hz, 20-bit word string data DM '(20) having a word transmission rate of 74.25 MBps is read from the memory unit 18 and supplied to the switch 20. The switch 20 is also supplied with the additional word data group DWT from the word data transmission unit 14. The additional word data group DWT has a word transmission rate of 74.25 MBps.

The switch 20 reads an additional word data group DWT from the word data transmission unit 14 at a word transmission rate of 74.25 MBps and the memory unit 18 in response to the control signal CSB from the switch control signal forming unit 16. 74.25 MBps
20-bit word string data DM ′ (20)
The word transmission rate read from the memory unit 17 is set to 7
20-bit word string data D at 4.25 MBps
Each of M ′ (20) is sequentially extracted for a predetermined word period. As a result, the switch 20 adds an additional word data group having a word transmission rate of 74.25 MBps to the 20-bit word string data DM '(20) whose word transmission rate has been converted to 74.25 MBps at a predetermined word interval. Composite 20 formed by insertion of DWT
Bit word string data DZ (20) is derived.

The additional word data group DWT having a word transmission rate of 74.25 MBps from the word data transmitting unit 14 has a predetermined code given thereto.
It is composed of a plurality of 20-bit word data including 0-bit word synchronization data. Then, the 20-bit word synchronization data included therein is, for example, A
And B, three 10-bit word data 3FFh, 000h and 000h (h) corresponding to three words of the EAV included in the SDTI signal format as shown in FIG.
Is a hexadecimal notation, and the same applies to the following.) 3FF: 3FFh, 0, which is three word data formed by multiplexing two data groups consisting of
00: 000h and 000000h are sequentially arranged. 3FF: 3FFh includes 10-bit word data 3FFh and 10-bit word data 3FF
h is bit-multiplexed into 20-bit word data, and 000000h is 10-bit word data 000h and 10-bit word data 000.
h is bit-multiplexed into 20-bit word data.

The additional word data group DWT having a word transmission rate of 74.25 MBps from the word data transmission unit 14 includes three 20-bit word data 3FF: 3FF which are 20-bit word synchronous data.
h, 000: 000h and 000: 000h, and other 20-bit word data.

Such an additional word data group DWT
Is, in one specific example, three consecutive 20-bit word data 3 which are 20-bit word synchronization data.
FF: 3FFh, 000,000: 000h and 00000: 000
Prior to h, arbitrary 20-bit word data DX is to be arranged. In the composite 20-bit word string data DZ (20) formed by inserting such an additional word data group DWT, the portion where the additional word data group DWT is inserted is as shown in FIG. 3, for example. You. 3, DM represents 20-bit word data forming 20-bit word string data DM '(20) read from each of the memory units 17 and 18 shown in FIG. , And the arrow t indicates the passage of time.

The additional word data group DWT
In another example of the specific example, three consecutive 20-bit word data 3FF: 3FFh, 0,000,000: 000h and 000: 0 which are 20-bit word synchronization data.
An arbitrary 20-bit word data DX is arranged before and after 00h. In the composite 20-bit word string data DZ (20) formed by inserting such an additional word data group DWT, the portion where the additional word data group DWT is inserted is as shown in FIG. 4, for example. You. Also in FIG. 4, the DM is the 2 read from each of the memory units 17 and 18 shown in FIG.
The 20-bit word data forming the 0-bit word string data DM '(20) is represented by DX.
0-bit word data, and an arrow t
Represents the passage of time.

As described above, the composite 20-bit word string data DZ (20) formed in the speed conversion / data insertion unit 13 is sent from the composite data formation unit 12, and is converted into parallel / serial (P / S). It is supplied to the conversion unit 21. In the P / S converter 21, the composite 20-bit word string data DZ (20) is subjected to P / S conversion for converting parallel data into serial data, and converted to the composite 20-bit word string data DZ (20). Forming serial data DZS based on the serial data DZS and transmitting the serial data DZS
Feed to 2. The transmission unit 22 transmits the serial data DZS
For example, in order to transmit through a data transmission line formed using a coaxial cable or an optical fiber, an electric signal suitable for a data transmission line formed using a coaxial cable, or an optical fiber is used. The signal is converted into a transmission signal SZ which is an optical signal suitable for the data transmission path formed and transmitted. Thereby, transmission of the serial data DZS is performed.

As described above, the 5-channel SDT
The 20-bit word string data DM (20) based on the I signals DTIS1 to DTIS5 is added to three consecutive 20-bit word data 3F as 20-bit word synchronization data.
F: 3FFh, 00000: 000h and 000: 000h
20-bit word string data DZ (20) formed by inserting an additional word data group DWT including
Is converted to serial data DZS and transmitted. At this time, a 5-channel SDTI signal DT which is subjected to multiplexing processing in a state where scramble processing has been performed is performed.
In each of IS1 to DTIS5, three consecutive 20-bit word data 3FF: 3FFh, 000000: 000h and 000: 0 which are 20-bit word synchronous data.
When the portion where 00h is to be formed appears, 20
There is no point in inserting 20-bit word synchronization data into the bit word string data DM (20).

A 5-channel SDTI signal DTIS1 to be subjected to multiplexing processing after being subjected to scramble processing
.., DTIS5, three consecutive 20-bit word data 3F which are 20-bit word synchronization data.
F: 3FFh, 00000: 000h and 000: 000h
Are formed by six consecutive 10-bit word data 3FFh, 3FFh, 000h, 00
0h, 000h and 000h are portions corresponding to those converted into serial data. That is, the SDTI signals DTI1 to DTI1 of the five channels subjected to the scramble processing are
In each of DTIS5, six consecutive 10-bit word data 3FFh, 3FFh, 000h, 000
The problem is whether or not a portion corresponding to the data obtained by converting h, 000h and 000h into serial data appears. In this regard, such portions will not appear substantially for the following reasons.

First, the scrambled SDT
In each of the I signals DTIS1 to DTIS5, m is 1
Assuming that there is a portion where m bits of “0” continue as an integer of 0 or more, the original data before the scramble processing of the portion is A (X) and B (X) as arbitrary data, (X); m-bit "0"sequence; B
(X) is multiplied by a formula (X + 1) and a ninth-order primitive polynomial: (X ⁹ + X ⁴ +1), that is, [A
(X); m bits of “0” continuation; B (X)] × (X +
1) × (X ⁹ + X ⁴ +1) = [A (X); m bits of “0” continuous; B (X)] × G (X), where G
(X) = (X + 1) × (X ⁹ + X ⁴ +1)).

Thus, [A (X); m-bit "0"
[Continuation of m bits of “0”] × G (X) in data expressed as B (X)] × G (X) is XXX
XXXXXXX is 10 bits obtained by adding the results of A (X) × G (X), and YYYYYYYYYY is B
XXXXXXXXXXX0... 0YYYYYYY as 10 bits obtained by adding the result of (X) × G (X)
YYY, where 0... 0 is a series of m-10 bits of “0”. Such data: XXXXXX
XXXXXX0... 0YYYYYYYYYY is considered to be present in each of the SDTI signals DTI1 to DTIS5 before the scramble processing. Depends on the scramble initial value, and can be considered as 2 ⁻¹⁰ .

The scrambled SDT
In each of the I signals DTIS1 to DTIS5, n is 1
Assuming that there is a portion where n bits of “1” continue as an integer of 0 or more, the original data before the scramble processing of the portion is A (X) and B (X) as arbitrary data, (X); n-bit "1"sequence; B
(X) is multiplied by a formula (X + 1) and a ninth-order primitive polynomial: (X ⁹ + X ⁴ +1), that is, [A
(X); n bits of “1” continuation; B (X)] × (X +
1) × (X ⁹ + X ⁴ +1) = [A (X); n-bit “1” continuation; B (X)] × G (X), where G
(X) = (X + 1) × (X ⁹ + X ⁴ +1)).

Thus, [A (X); n-bit "1"
Of data; B (X)] × G (X)
Where [continuation of n-bit “1”] × G (X) is
[Continuation of n-bit “1”] × (X + 1) = Xⁿ+1
Because there is (Xⁿ+1) × (X ⁹+ X^Four+1) = (X⁹
+ X^Four+1) × Xⁿ+ (X⁹+ X^Four+1) and XX
XXXXXXXXXX is the sum of the results of A (X) × G (X)
10 bits and YYYYYYYYYY is B
10 bits obtained by adding the result of (X) × G (X)
XXXXXXXXXXX0 ... 0YYYYYYY
YYY, (where 0... 0 is n-10 bits
(Continuation of “0”). Such data: XXXXXX
XXXXXX0 ... 0YYYYYYYYYY is
Of the SDTI signals DTI1 to DDIS5 before the
Although it is thought that each of them can exist,
As a result, based on such data, a sequence of n bits of “1”
The probability of occurrence depends on the initial scramble value.
And 2^-TenCan be considered.

The scrambled 5-channel SDTI signals DTIS1 to DTIS5 are thus obtained.
In each of the six consecutive 10-bit word data 3FFh, 3FFh, 000h, 000h, 000h
And the probability that a portion corresponding to 000h converted to serial data appears is as small as 2 ^-60 and can be substantially ignored. Accordingly, the SDTI signals DTI1 to DTI1 of the five channels subjected to the scramble processing are
In each of DTIS5, six consecutive 10-bit word data 3FFh, 3FFh, 000h, 000
It can be considered that the portions corresponding to those obtained by converting h, 000h and 000h into serial data do not substantially appear.

In the data transmission apparatus shown in FIG. 1 as described above, the P / S conversion section 21 and the transmission section 22 convert the 20-bit word string data having a word transmission rate of 74.25 MBps to the bit transmission rate. Is 1.485 Gbp
The P / S conversion unit 21 and the transmission unit 22 are used, for example, for transmitting a digital video signal under an HDTV system. Can be configured by effectively utilizing the integrated circuit (IC) element provided in the above. Therefore, the bit transmission rate is set to 270 Mbp.
The SDTI signal of 5 channels as s can be obtained as a data synchronization state required for the reproduction process on the receiving side by 20-bit word synchronization data without any need for developing new circuit elements and the like. This can be done by means that can be easily prepared.

FIG. 5 shows an example of a data transmission method according to the invention described in claims 1, 2, 4, 5 or 6 in the claims of the present application. An example of the data transmission device according to the invention described in Item 7 is shown.

In the example shown in FIG.
Channel SDTI signals DTIP1, DTIP2, D
TIP3, DTIP4, and DTIP5 are supplied to the 20-bit word string data forming unit 31. Each of the five channels of SDTI signals DTIP1 to DTIP5 is shown in FIG.
A and B are 10-bit quantized digital signals that are 10-bit word string data formed in accordance with the SDTI signal format, and are parallel data having a word transmission rate of, for example, 27 MBps. , Are synchronized with each other.

In the 20-bit word string data forming unit 31, SDTI signals DTIP1 to DT of five channels are provided.
In IP5, from each of them, for example, 1 word = 10
A multiplexing process for sequentially extracting and multiplexing the bit addresses as 10-bit data is performed to form 20-bit word string data DM (20) having a word transmission rate of, for example, 67.5 MBps. At this time, scramble processing is performed on the 10-bit data by dividing the sequentially extracted 10-bit data by a ninth-order primitive polynomial: X ⁹ + X ⁴ +1 and further by dividing the expression by X + 1 to perform scramble processing. The multiplexing process is performed on the resulting 10-bit data to obtain 20-bit word string data DM (20). Then, 20-bit word string data DM (20) having a word transmission rate of 67.5 MBps obtained from the 20-bit word string data forming section 31 is supplied to the composite data forming section 32.

In the composite data forming section 32, the 20-bit word string data DM (20) from the 20-bit word string data forming section 31 is converted into a speed conversion / data inserting section 33.
Supplied to Further, the speed conversion / data insertion unit 33 receives, from the word data transmission unit 34, additional word data composed of a plurality of 20-bit word data including 20-bit word synchronization data to which a predetermined code has been assigned. A group DWT is provided.

In the speed conversion / data insertion unit 33, the word transmission rate is set to 67.5 MBps.
For the 0-bit word string data DM (20), the word transmission rate is, for example, from 67.5 MBps to 7
While performing speed conversion to convert to 4.25 MBps,
At a predetermined word interval, an additional word data group DWT including the 20-bit word synchronization data from the word data sending unit 34 is inserted, and thereby, the word transmission rate based on the five-channel SDTI signals DTIP1 to DTIP5 is reduced. For example, composite 20-bit word string data DZ (20) of 74.25 MBps is formed.

A specific configuration example of the speed conversion / data insertion unit 33 is the same as the specific configuration example of the speed conversion / data insertion unit 13 shown in FIG. The additional word data group DWT including the 20-bit word synchronization data transmitted from the word data transmission unit 34 also corresponds to FIG.
20 sent from the word data sending unit 14 shown in FIG.
It is the same as the additional word data group DWT including the bit word synchronization data.
Three consecutive 20 bits that are 20-bit word synchronization data
Bit word data 3FF: 3FFh, 000: 000
h and 000: 000h, arbitrary 20-bit word data DX is arranged before the h and 000: 000h. Another specific example is that three consecutive 20-bit words which are 20-bit word synchronization data are used. Data 3FF: 3FFh,
Arbitrary 20-bit word data DX is arranged before and after 000: 000h and 000000h.

The speed conversion / data insertion unit 33 performs the same operation as the speed conversion / data insertion unit 13 shown in FIG. 1, so that the portion where the additional word data group DWT is inserted becomes For example, as shown in FIG. 3 or FIG.
Composite 20-bit word string data DZ (20) with 4.25 MBps is obtained.

As described above, the composite 20-bit word string data DZ (20) formed in the speed conversion / data insertion section 33 is sent from the composite data formation section 32 and supplied to the P / S conversion section 35. Is done. P / S converter 35
, The composite 20-bit word string data DZ (2
0), P for converting parallel data into serial data
/ S conversion to obtain composite 20-bit word string data DZ
The serial data DZS based on (20) is formed, and the serial data DZS is supplied to the transmission unit 36. The transmission unit 36 transmits the serial data DZS through, for example, a data transmission line formed using a coaxial cable or an optical fiber, so that an electric signal suitable for a data transmission line formed using a coaxial cable is used. Alternatively, the signal is converted into a transmission signal SZ which is an optical signal suitable for a data transmission path formed by using an optical fiber and transmitted. Thereby, transmission of the serial data DZS is performed.

As described above, the 5-channel SDT
20-bit word string data DM (20) based on the I signals DTIP1 to DTIP5 are added to three consecutive 20-bit word data 3F which are 20-bit word synchronization data.
F: 3FFh, 00000: 000h and 000: 000h
20-bit word string data DZ (20) formed by inserting an additional word data group DWT including
Is converted to serial data DZS and transmitted. At this time, a 5-channel SDTI signal DTIP
1 to DTIP5, 10-bit data is sequentially extracted, scramble processing is performed on the extracted 10-bit data, and the scrambled 10-bit data is obtained.
In the 20-bit word string data DM (20) obtained by performing the multiplexing process on the bit data, three consecutive 20-bit word data 3FF: 3FFh, 000: 000h and 0 which are 20-bit word synchronous data are obtained.
If a portion corresponding to 00: 000h appears, there is no point in inserting 20-bit word synchronization data into the 20-bit word string data DM (20).

In the 20-bit word string data DM (20), three consecutive 2 bits which are 20-bit word synchronization data
0-bit word data 3FF: 3FFh, 00:00
When the portions corresponding to 0h and 000: 000h appear, the SDTI signals DTIP1 to DTI of five channels are used.
10-bit data is sequentially taken out from each of P5, and six consecutive 10-bit word data 3FFh, 3FFh, 000h, 00 are included in data obtained by performing scramble processing on the taken-out 10-bit data.
A portion corresponding to the data obtained by converting 0h, 000h and 000h into serial data appears. However, in this regard, for the same reason as in the case of the scrambled 5-channel SDTI signals DTI1 to DTIS5 in the example shown in FIG.
10-bit data is sequentially extracted from each of the channel SDTI signals DTIP1 to DTIP5, and scramble processing is performed on the extracted 10-bit data, and six consecutive 10-bit word data 3FFh, 3FFh, 000h, 000h, 0
It can be considered that a portion corresponding to the data obtained by converting 00h and 000h into serial data does not substantially appear, and therefore, the 20-bit word string data DM (20)
3 consecutive 20-bit word data 3FF: 3FFh, 000: 0, which is 20-bit word synchronous data in the
It can be considered that the portions corresponding to 00h and 000: 000h do not substantially appear.

Even in the data transmission apparatus shown in FIG. 5 as described above, the P / S conversion unit 35 and the transmission unit 36 transmit the 20-bit word string data having the word transmission rate of 74.25 MBps to the bit transmission rate. Is 1.485 Gbp
The P / S conversion unit 35 and the transmission unit 36 are, for example, used for transmitting a digital video signal under an HDTV system. Can be configured by effectively utilizing the integrated circuit (IC) element provided in the above. Therefore, the bit transmission rate is set to 270 Mbp.
The SDTI signal of 5 channels as s can be obtained as a data synchronization state required for the reproduction process on the receiving side by 20-bit word synchronization data without any need for developing new circuit elements and the like. This can be done by means that can be easily prepared.

FIG. 6 shows a composite 20-bit word string transmitted from the transmission unit 22 in the example of the data transmission apparatus shown in FIG. 1 according to the example of the data transmission method according to the invention described in the claims of the present application. 1 shows an example of a data receiving device that receives a transmission signal SZ based on serial data DZS obtained by converting data DZ (20).

In the example of the data receiving apparatus shown in FIG. 6, for example, an electric signal suitable for a data transmission path formed by using a coaxial cable or an optical fiber formed by using an optical fiber is used. A receiving unit 41 is provided for receiving a transmission signal SZ which is an optical signal suitable for the data transmission path. When receiving the transmission signal SZ, the receiving unit 41 reproduces the serial data DZS based on the received transmission signal SZ, and reproduces the reproduced serial data DZS.
ZS is supplied to a serial / parallel (S / P) conversion / synchronous data detection unit 42.

In the S / P conversion / synchronous data detector 42, the serial data DZS is subjected to S / P conversion,
For example, as shown in FIG. 7A or FIG.
Compound 20-bit word string data DZ (2) which is parallel data with a word transmission rate of 74.25 MBps
0) is formed. Then, the composite 20-bit word string data D obtained from the S / P conversion / synchronization data detection unit 42
Z (20) is supplied to the speed conversion / synchronization data separation unit 43.

The S / P converter / synchronous data detector 42
, The composite 20-bit word string data DZ (2
0) in the additional word data group DWT.
Three consecutive 20-bit word data 3FF: 3FFh, 000000h which are 0-bit word synchronous data
And 000: 000h, and sends out a synchronous data detection output signal SWS. This synchronous data detection output signal S
WS is, for example, the composite 20-bit word string data DZ detected by the S / P conversion / synchronization data detection unit 42.
Three consecutive 20-bit word data 3FF: 3FF in the additional word data group DWT in (20)
Corresponding to the last of h, 000: 000h and 000: 000h, it is obtained as shown in FIG. 7B or FIG. 8B. Note that the arrow t in FIGS. 7 and 8 indicates the passage of time.

As described above, the synchronous data detection output signal SWS obtained from the S / P conversion / synchronous data detection section 42
Is supplied to the control signal forming unit 44. Then, in the control signal forming section 44, the synchronous data detection output signal SW
A synchronization control signal CW based on S is formed.

The speed conversion / synchronization data separation unit 43 to which the composite 20-bit word string data DZ (20) is supplied from the S / P conversion / synchronization data detection unit 42 has a synchronization control signal from the control signal formation unit 44. CW is also provided. And
In the speed conversion / synchronization data separation unit 43, under the control of the word synchronization by the synchronization control signal CW, a 20-bit word having a word transmission rate of 74.25 Mbps is obtained from the composite 20-bit word string data DZ (20). Column data DM (20) and additional word data group DW
T is separated and fetched, and the speed conversion of the fetched 20-bit word string data DM (20) from a word transmission rate of 74.25 MBps to a word transmission rate of 67.5 MBps. Is applied.

The word transmission rate obtained from the rate conversion / synchronization data separation unit 43 is set to 67.5 MBps.
The bit word string data DM (20) is output to the data separation unit 4
5 is supplied. In the data separation unit 45, 20 bit data in each 20-bit word data constituting the 20-bit word string data DM (20) from the speed conversion / synchronization data separation unit 43 are sequentially grouped into 10 groups of 10 bits each. The state in which the data is divided and the bit data of each group is individually taken out continues,
Based on the 0-bit word string data DM (20), each of the five channels of SDTI signals DTI1, DSIS2, DDIS3, D which is scrambled serial data having a bit transmission rate of 270 Mbps is formed.
TIS4 and DTIS5 are formed separately from each other. As a result, the reproduced 5
The SDTI signals DTIS1 to DTIS5 of the channel are derived. In this way, each of the five channels of SDTI signals DTIS1 to DTIS5, each of which is serial data having a bit transmission rate of 270 Mbps, is reproduced.

FIG. 9 shows a composite 20-bit word string transmitted from the transmission unit 36 in the example of the data transmission apparatus shown in FIG. 5 according to the example of the data transmission method according to the invention described in the claims of the present application. 1 shows an example of a data receiving device that receives a transmission signal SZ based on serial data DZS obtained by converting data DZ (20).

In the example of the data receiving apparatus shown in FIG. 9, for example, an electric signal suitable for a data transmission path formed by using a coaxial cable or an optical fiber is formed by using an optical fiber. A receiving unit 51 is provided for receiving a transmission signal SZ which is an optical signal suitable for the data transmission path. When receiving the transmission signal SZ, the receiver 51 reproduces the serial data DZS based on the received transmission signal SZ, and reproduces the reproduced serial data DZS.
The ZS is supplied to the S / P conversion / synchronous data detection unit 52.

In the S / P conversion / synchronous data detector 52, the serial data DZS is subjected to S / P conversion,
For example, as shown in FIG. 7A or FIG.
Compound 20-bit word string data DZ (2) which is parallel data with a word transmission rate of 74.25 MBps
0) is formed. The composite 20-bit word string data D obtained from the S / P conversion / synchronization data detection unit 52
Z (20) is supplied to the speed conversion / synchronization data separation unit 53.

The S / P converter / synchronous data detector 52
, The composite 20-bit word string data DZ (2
0) in the additional word data group DWT.
Three consecutive 20-bit word data 3FF: 3FFh, 000000h which are 0-bit word synchronous data
And 000: 000h, and sends out a synchronous data detection output signal SWS. This synchronous data detection output signal S
WS is the composite 20-bit word string data DZ detected by the S / P conversion / synchronization data detection unit 52, for example.
Three consecutive 20-bit word data 3FF: 3FF in the additional word data group DWT in (20)
Corresponding to the last of h, 000: 000h and 000: 000h, it is obtained as shown in FIG. 7B or FIG. 8B.

As described above, the synchronous data detection output signal SWS obtained from the S / P conversion / synchronous data detector 52
Is supplied to the control signal forming unit 54. Then, in the control signal forming section 54, the synchronous data detection output signal SW
A synchronization control signal CW based on S is formed.

The speed conversion / synchronization data separation unit 53 to which the composite 20-bit word string data DZ (20) is supplied from the S / P conversion / synchronization data detection unit 52 is provided with a synchronization control signal from the control signal formation unit 54. CW is also provided. And
In the speed conversion / synchronization data separation section 53, under the control of the word synchronization by the synchronization control signal CW, a 20-bit word having a word transmission rate of 74.25 MBps is obtained from the composite 20-bit word string data DZ (20). Column data DM (20) and additional word data group D
The WT and the WT are separated and taken out, and the word transmission rate is set to 7 in the 20-bit word string data DM (20).
The rate conversion from the rate of 4.25 MBps to the rate of the word transmission rate of 67.5 MBps is performed.

The word transmission rate obtained from the rate conversion / synchronous data separation section 53 is set to 67.5 MBps.
The bit word string data DM (20)
5 is supplied. In the data separation unit 55, 20 bit data in each 20-bit word data constituting the 20-bit word string data DM (20) from the speed conversion / synchronization data separation unit 53 are sequentially converted into 10-bit 10-bit data. The extracted 10-bit data is multiplied by the expression: X + 1, and further, a ninth-order primitive polynomial:
By performing a descrambling process on 10-bit data by multiplying by X ⁹ + X ⁴ +1 to obtain 10-bit data before scrambling, it is sequentially divided into five groups and continuously taken out. Thereby, based on the 20-bit word string data DM (20), the 5-channel SDTI signal DTI is converted into parallel data each having a word transmission rate of 27 MBps.
P1, DTIP2, DTIP3, DTIP4 and DTI
P5 is formed as being separated from each other. Thereby, the reproduced 5-channel SDTI signals DTIP1 to DTIP5 are derived from the data separation unit 55.
In this way, each has a word transmission rate of 27 MBp
SDT of 5 channels converted to parallel data as s
Each of the I signals DTIP1 to DTIP5 is reproduced.

In the example of the data transmission method implemented by using the example of the data transmission apparatus shown in FIG. 1 or FIG. 5, for example, a 5-channel SDTI signal is multiplexed and transmitted. However, the number of multiplexed transmitted SDTI signals is not limited to five channels, but may be any number of channels.

Further, in the example of the data transmission method implemented by using the example of the data transmission apparatus shown in FIG. 1, the SDTI signal, which is multiplexed and transmitted as 5-channel serial data, is transmitted by each bit transmission. The rate is set to, for example, 270 Mbps.
The bit transmission rate of each of the TI signals is 270 Mbps.
It is not limited to. Further, in the example of the data transmission method implemented by using the example of the data transmission apparatus shown in FIG. 5, the SDTI signal which is multiplexed and transmitted as five-channel parallel data has the respective word transmission rates, For example, although the data rate is set to 27 MBps, the word transmission rate of each of the SDTI signals, which are multiplexed and transmitted as five-channel parallel data, is also 27 bits.
It is not limited to MBps.

[0072]

As apparent from the above description, according to the data transmission method according to any one of the first to sixth aspects of the present invention,
The composite 20-bit word string data based on a plurality of SDTI signals transmitted to be converted into serial data and transmitted is provided with a predetermined code.
Bit word synchronization data will be included, and such 20-bit word synchronization data is, for example, in claim 2.
As in the data transmission method according to the invention described in
A plurality of 20-bit word data to which a predetermined code is assigned is selected to be continuous with a specific arrangement. Then, the 20-bit word synchronization data given the predetermined code and included in the composite 20-bit word string data is received by the receiving side that receives serial data based on the composite 20-bit word string data including the same. It is to be properly detected as word synchronization data required for processing for reproducing a plurality of SDTI signals from composite 20-bit word string data obtained based on the obtained serial data. Therefore, on the receiving side, a state is ensured in which the data synchronization state required for the reproduction processing of a plurality of SDTI signals based on the received composite 20-bit word string data is reliably obtained. become.

In the data transmission method according to any one of the first to sixth aspects of the present invention, a predetermined code is provided. Conversion of composite 20-bit word string data to which bit word synchronization data is added into serial data, transmission of the converted serial data, and
The receiving side receives the serial data, converts the received serial data into composite 20-bit word string data, and uses, for example, a transmission circuit device used for transmitting and receiving a digital video signal under an HDTV system. You can do it. Therefore, according to the data transmission method according to any one of the first to sixth aspects of the present invention,
A plurality of SDTI signals can be multiplexed and transmitted so that they can be reliably reproduced on the receiving side by means that can be prepared relatively easily.

Further, in the data transmission apparatus according to the invention described in claim 7 of the present application, a plurality of SDTIs which are transmitted by a data transmission means after being converted into serial data and transmitted. The composite 20-bit word string data based on the signal includes 20-bit word synchronization data provided with a predetermined code, and the 20-bit word synchronization data includes:
For example, a plurality of 20-bit word data to which a predetermined code is assigned is selected to be continuous with a specific arrangement. Then, the 20-bit word synchronization data given the predetermined code and included in the composite 20-bit word string data is received by the receiving side that receives serial data based on the composite 20-bit word string data including the same. It is to be properly detected as word synchronization data required for processing for reproducing a plurality of SDTI signals from the composite 20-bit word string data obtained based on the serial data obtained, On the receiving side, a state in which the data synchronization state required for the reproduction processing of a plurality of SDTI signals based on the received composite 20-bit word string data is reliably obtained.

According to such a data transmission apparatus according to the invention as set forth in claim 7 of the present application, a composite in which a 20-bit word synchronous data to which a predetermined code is given is added is added. The conversion of the 20-bit word string data into serial data, the transmission of the converted serial data, and the reception side receiving the serial data, converting the received serial data into composite 20-bit word string data, For example, it is possible to use a transmission circuit device used for transmission and reception of a digital video signal under an HDTV system. , So that the data can be multiplexed and transmitted so as to be surely reproduced on the receiving side.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
FIG. 13 is a block diagram showing an example of a data transmission apparatus according to the invention described in claim 7 in the claims of the present application, in which the example of the data transmission method according to the invention described in 2, 3, or 6 is implemented. is there.

FIG. 2 is a block diagram showing a specific configuration example of a rate conversion / data insertion unit in the example of the data transmission device shown in FIG. 1;

[Fig. 3] Claims 1 and 2 in the claims of the present application.
7 is a time chart for explaining an example of a data transmission method according to the invention described in 2, 3, or 6.

[Fig. 4] Claims 1 and 2 in the claims of the present application.
7 is a time chart for explaining an example of a data transmission method according to the invention described in 2, 3, or 6.

[Fig. 5] Claims 1 and 2 in the claims of the present application.
A block configuration showing an example of the data transmission device according to the invention described in claim 7 in the claims of the present application, in which the example of the data transmission method according to the invention described in 2, 4, 5, or 6 is implemented. FIG.

[Fig. 6] Claim 1, Claim 1 in the claims of the present application.
FIG. 7 is a block diagram showing an example of a data receiving device that receives a transmission signal transmitted according to the example of the data transmission method according to the invention described in 2, 3, or 6.

FIG. 7 is a time chart for explaining an operation of the example of the data receiving apparatus shown in FIG. 6;

FIG. 8 is a time chart for explaining the operation of the example of the data receiving apparatus shown in FIG. 6;

FIG. 9: Claim 1 in the claims of the present application
FIG. 9 is a block diagram showing an example of a data receiving apparatus that receives a transmission signal transmitted according to the example of the data transmission method according to the invention described in 2, 4, 5, or 6.

FIG. 10 is a conceptual diagram provided for describing an example of an SDTI signal format.

[Explanation of symbols]

11, 31... 20-bit word string data forming unit,
12, 32 ... composite data forming unit, 13, 33 ...
・ Speed conversion / data insertion unit, 14, 34 ... word data transmission unit, 15, 20 ... switch, 16
..Switch control signal forming section, 17, 18 ... memory section, 19 ... memory control signal forming section, 21,3
5 ... P / S converter, 22, 36 ... transmitter,
41, 51 ... receiving unit, 42, 52 ... S / P conversion / synchronous data detecting unit, 43, 53 ... speed conversion
Synchronous data separation unit, 44, 54 ... control signal formation unit, 45, 55 ... data separation unit

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (Reference) H04N 7/081 F term (Reference) 5C059 KK00 MA00 MD02 PP04 RB02 RB10 RB16 RC02 RD03 RE02 SS06 UA02 UA05 UA28 UA35 5C063 AA20 AB03 AB07 AC01 AC05 CA14 CA20 CA23 CA40 DA01 DA05 DA07 DA13 DB10 5K028 AA12 EE03 KK01 5K047 AA00 CC02 DD01 DD02 MM02 MM11

Claims (7)

[Claims] 1. A multiplexing process is performed on a plurality of digital signals each formed in accordance with a specific signal format used for transmitting compressed digital video data or video and audio data to form 20-bit word string data. Then, a transmission rate conversion process is performed on the 20-bit word string data, and an additional word data group including 20-bit word synchronization data provided with a predetermined code is inserted at predetermined word intervals. A data transmission method for forming composite 20-bit word string data, converting the composite 20-bit word string data into serial data, and transmitting the serial data for transmission. 2. An additional word data group is selected so as to include, as a 20-bit word synchronization data, a portion in which a plurality of 20-bit word data to which a predetermined code is assigned is connected in a specific arrangement. The data transmission method according to claim 1, wherein: 3. A digital signal obtained by subjecting a 10-bit quantized digital signal to scramble processing and serially transmitting the plurality of digital signals, and having a bit synchronization relationship with each other. The data transmission method according to claim 1. 4. The method according to claim 1, wherein each of the plurality of digital signals is parallel data converted into a 10-bit quantized digital signal and has a word synchronous relationship with each other. Data transmission method. 5. When multiplexing a plurality of digital signals to form 20-bit word string data, bit data of a predetermined number of bits is sequentially extracted from each of the plurality of digital signals, and the extracted bit data is read. 5. The data transmission method according to claim 4, wherein a scrambling process is performed on the bit data, and a multiplexing process is performed on the scrambled bit data. 6. A plurality of 20-bit word data to which an additional word data group is assigned a predetermined code based on timing reference data included in each of a plurality of digital signals, with a specific arrangement. 6. The data transmission method according to claim 3, wherein the portion is selected to include the 20-bit word synchronization data. 7. A multiplexing process is performed on a plurality of digital signals, each of which conforms to a specific signal format used for transmitting compressed digital video data or video and audio data, to form a 20-bit word string. 20-bit word string data forming means for forming data;
The 20-bit word string data obtained from the 0-bit word string data forming means is subjected to transmission rate conversion processing, and includes predetermined 20-bit word synchronization data provided with a predetermined code at predetermined word intervals. Composite data forming means for forming composite 20-bit word string data by inserting an additional word data group, and converting the composite 20-bit word string data obtained from the composite data forming means into serial data; A data transmission means for transmitting the data for transmission.