JPH10191282A - Data transmission method and communication system, transmission device and reception device using the same - Google Patents

Abstract

(57) [Summary] [PROBLEMS] In a communication system such as satellite communication or cable television, when data transmitted from a transmission side cannot be normally received by a reception side, data can be retransmitted from the transmission side, and the reception side can transmit the data. It is possible to reliably receive data. A transmitting station adds attribute information for retransmission to data to be transmitted and transmits the data to a receiving device. When the transmitting station transmits a command for instructing the receiving device to perform the receiving process in the retransmission mode, the receiving device records the attribute information of the data that could not be normally received in the memory. When receiving an instruction to output the reception result from the transmitting station, the receiving device transmits the reception result recorded in the memory. The transmitting station creates a retransmission file based on this. After transmitting the retransmission file transmission start command, the transmitting station transmits the retransmission file.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data retransmission method and a communication system, a transmission apparatus, and a reception apparatus using the same, and more particularly, to multiplex video, audio, and other data on the transmission side such as digital satellite communication and cable television. The present invention relates to a data reproducing method in a communication system for transmitting data to a plurality of receiving sides, and a communication system, a transmitting device, and a receiving device using the same.

[0002]

2. Description of the Related Art In recent years, a technique for transmitting digital data using a transmission path of satellite broadcasting, cable television, and terrestrial broadcasting, which has been used for analog television broadcasting, has been developed in recent years. According to this technology, analog TV broadcasting has been able to broadcast only one program on one channel until now, but it is now possible to broadcast several programs on one channel. further
MPEG2 (Moving Picture Experts Group 2 ISO / IEC 1381
Combining with digital compression technology such as 8) enables broadcasting of multiple programs on one channel, and new services such as multi-channel broadcasting and video on demand have begun.

[0003] With the digitization of transmission data,
In addition to broadcasting services such as television programs, transmission of various data such as video, audio, text, programs, and executable files has been considered. Until now, such data transmission has been performed on a network connecting computer systems such as the Internet, but by using a satellite broadcast transmission line, transmission bandwidth of a problem which is problematic in a system such as the Internet. Data transmission in units of several Gbits, which overcomes the restrictions, becomes possible.

[0004] Assurance of the quality of transmission data is compared between a conventional broadcast program and data transmission on the Internet.
In the case of a broadcast program, the program is received and viewed in real time, and a slight error in data is permissible to the extent that the screen or sound is disturbed. On the other hand, the above-mentioned various data such as texts, programs, and executable files are temporarily stored on a hard disk or the like on the receiving side, and then read out and used, and it is required that the received data be free from errors. You. Although some error can be corrected by using the error correction technique, if an error that cannot be corrected still remains, even if it is 1 bit, the effect is large and some data cannot be used at all.

[0005] On the other hand, in communication between computer systems such as the Internet, end-to-end communication is required between terminals.
They were connected end-to-end to send and receive data. Open system interconnection (OSI: Open S
HDLC (HiStem Interconnection), which is a data link layer communication protocol referred to in the seven-layer model.
gh Level Data Link Control Procedure), TCP (Transmission C)
ontrol Protocol / Internet Protocol), the reliability of data transmitted and received between terminals was guaranteed.

[0006]

However, in satellite broadcasting, cable television, terrestrial broadcasting, and the like, the transmitting side has not managed whether or not the transmitted data has been normally received by the receiving side. Further, the receiving side notifies the transmitting side that there is an error in the received data, requests retransmission of the data that could not be received, and receives the retransmitted data from the transmitting side.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to prevent data transmitted from a transmitting side from being properly received by a receiving side in satellite communication, cable television, and communication using terrestrial waves. In this case, it is an object of the present invention to provide a retransmission method capable of retransmitting the data from the transmission side and reliably receiving the data on the reception side, and a communication system, a transmission apparatus, and a reception apparatus using the same.

[0008]

In order to solve the above-mentioned problems, a data transmission method according to the present invention provides a method for transmitting, on a transmitting side, one or more application data and related information including information on each application data by time division multiplexing. In a system for transmitting data to a receiving side, information for controlling a process of receiving application data on the receiving side is added to the related information.

More specifically, a command instructing a normal transmission process from the transmission side to the reception side, a command instructing reception in a retransmission mode, a command instructing a reception result to be output to the transmission side, One of the commands for notifying the start of transmission of the retransmission file is transmitted as information for controlling the receiving process of the application data on the receiving side.

[0010] Further, the application data transmitted from the transmission side is provided with attribute information to be used for retransmission.

When the receiving side is instructed to receive in the retransmission mode from the transmitting side, if the application data transmitted from the transmitting side cannot be normally received, the application data of the application data which could not be received cannot be received. The attribute information is recorded as a reception result. When receiving an instruction to output the reception result from the transmission side, the reception side transmits the reception result recorded in this memory. The transmitting station creates a retransmission file based on this. After transmitting the retransmission file transmission start command, the transmitting station transmits the retransmission file.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The following embodiments of the present invention will be described with reference to embodiments in which the present invention is applied to a satellite communication system. In the embodiment, first, normal transmission processing in a general satellite communication system will be described, and then the retransmission method of the present invention will be described with reference to the flow of operations on the transmission side and the reception side. Next, the configurations of the transmitting station and the receiving device and the configuration of retransmitted data to be transmitted and received will be shown, and the embodiments of the present invention will be described in further detail based on the operations of these components. Next, the format of related information transmitted from the transmitting station to the receiving device for controlling retransmission will be described, and finally another configuration example of the receiving device will be described.

[1. Normal Transmission Process in Satellite Communication System] First, a general configuration of a satellite communication system and a normal transmission process will be described with reference to FIG.

FIG. 1 is a configuration diagram of a general satellite communication system.

In the transmitting station 106, the multiplexing device 102 time-division multiplexes video, audio, various data, and the like (hereinafter, application data), and outputs a multiplexed data stream. At this time, a time division frame identification number is added to each time division frame. The time-division frame identification number is used to distinguish application data, and takes a different value for each application. The related information generation device 101 generates a scramble key applied to application data so that only a recipient who has a right to receive can receive the application data. Unscrambling with it (hereinafter descrambling)
Related information 1 and related information 2 which are two types of related information including control information for the user. The related information 1 and the related information 2 are input to the multiplexer 102 and time-division multiplexed together with the application data. At this time, 2
Time-division frame identification numbers are added to the two pieces of related information. On the other hand, the scramble key is passed to the scramble device 103. The scramble device 103 includes the related information generation device 10
Based on the scramble key received from 1, scramble the corresponding application data. The multiplexed data stream ST1 output from the scrambler 103 is modulated by the transmitter 104, then converted into a 14 GHz band signal used for satellite communication, and transmitted from the antenna 105 to the receiver via the satellite 107. Is done.

In receiving apparatus 114, data transmitted from transmitting station 106 is received by antenna section 108, receiving section 109 performs frequency conversion and demodulation processing, and passes multiplexed data stream ST 1 to descramble section 110. The descrambler 110 uses the scramble key received from the related information processor 113 to descramble application data in the multiplexed data stream corresponding to the key. The separation unit 111 receives the descrambled multiplexed data stream, separates and outputs a time-division frame of each application data such as video, audio, data, etc., and separates the time-division frame of the related information 1 and the related information 2 from each other. To separate. Among them, the time-division frame of the related information 1 includes the information of the scramble key (encrypted scramble key), and the time-division frame of the related information 2 is used to decrypt the encryption applied to the scramble key. (Hereinafter, work key information) is included.
The related information processing unit 113 extracts the work key included in the related information 2 and uses the work key to obtain a scramble key from the scramble key information included in the related information 1, and passes the scramble key to the descramble unit 110.

The above is the ordinary conditional access transmission processing in the satellite communication system.

[0018] The limited reception means a mechanism in which only a recipient having a legitimate right receives application data.

Here, the related information 1 is for transmitting control information for each application data, and as a specific example, the EC of MPEG2 SYSTEMS (ISO / IEC 13818-1).
There is common information of M (Entitlement Control Message) data and a report of the Telecommunications Technology Council Advisory No. 74 Partial Report. The related information 2 is for transmitting contract information and the like relating to an individual. As a specific example, MPEG2 SYSTEMS
(ISO / IEC 13818-1) EMM (Entitlement Managemen)
t Message) There is data and individual information of the report of the Telecommunications Technology Council Advisory Council No. 74.

[2. Retransmission Processing] [2.1 Outline] In order to enable retransmission of application data, in the present embodiment, the total amount of data to be transmitted and the data currently being transmitted are added to the application data for which reliable reception is required. Attribute information such as a number indicating the position of the entire data and the number of the last data is added and transmitted. Details of this attribute information will be described later.

In this embodiment, an area for writing a command for retransmission control is provided in the related information 1 or the related information 2 (both may be used). Send instructions. There are three types of this command. The first is a “retransmission mode instruction”. This discriminates retransmission processing from normal transmission processing, and notifies the transmitting side to the receiving side that data to be transmitted from now on is data to be retransmitted if data cannot be reliably received. Upon receiving this command, the receiving side prepares for reception in the retransmission mode, performs error detection on the received application data, and records the result. The second is a “reception result output instruction”. This is for requesting the receiving side to output the reception result of the application data. When receiving this instruction, the receiving side transmits the recorded reception result to the transmitting side. On the transmitting side, based on the reception result sent from each receiving device,
Create a resend file. The third is "retransmission start instruction"
This is for notifying the receiving side that the retransmission file created by the transmitting side based on the reception result output from the receiving side will be retransmitted.

The normal transmission processing described above is added to the three commands for instructing the retransmission processing, and there are a total of four commands for instructing the transmission mode.

The reception result is transmitted from the receiving side to the transmitting side using a ground line such as a telephone line. In a system having a two-way transmission line such as a cable television, an up line may be used.

[2.2 Flow of Retransmission Method] Next, the flow of the retransmission method according to the present embodiment will be described with reference to FIGS.

FIG. 2 is a flowchart of the transmission side processing of the retransmission method of the present invention.

FIG. 3 is a flowchart of the receiving side processing of the retransmission method of the present invention.

(1) Flow on the transmitting side On the transmitting side, some event occurs (S
201), it is determined whether or not the event is a distribution event related to the distribution of application data (S202). If the event is not a distribution event, a process corresponding to the event is performed, and the process returns to the event waiting state. If a distribution event has occurred, it is determined whether or not the distribution event is an event for instructing retransmission processing (S203). If an instruction for retransmission processing is made, the process proceeds to S205; Perform normal transmission processing. The processing from S205 is the retransmission processing.

In the retransmission process, first, it is determined whether or not the distribution event is a retransmission mode instruction among the three types of retransmission instruction commands described above (S205). In the case of the retransmission mode instruction, the transmitting side creates related information including the retransmission mode instruction command (S206), and distributes the created related information to the receiving side (S207). Although not shown, the receiving side prepares to receive the retransmitted application data in response to the retransmission mode instruction command. Subsequently, the transmission side distributes the application data to the reception side in the retransmission mode (S208). When the distribution ends, it returns to. Although not shown, the receiving side checks whether there is any error in the received application data and records the reception result.

Next, if the event that has occurred in S201 is a distribution event and is a reception result output instruction among the three types of retransmission instructions, after the processing in S202, S203, and S205, is it a reception result output instruction? A determination is made (S209), and the process proceeds to S210. Then, related information including the reception result output instruction command is created (S
210), and distribute the created related information to the receiving side (S2).
11). Although not shown, the reception side receives the output instruction of the reception result and transmits the recorded reception result to the transmission side. The transmitting side collects the received reception results (S21).
2) Check whether retransmission is necessary (S213).
If there is no need for retransmission, the process returns to the step. If necessary, a retransmission file is created and prepared (S214).

Next, when the generated event is a distribution event and is a retransmission start instruction among three types of retransmission processing instructions, S201, S202, S203, S205, S20
After the process of No. 9, it is determined whether it is a retransmission file transmission start instruction (S215), and the process proceeds to S216. Then, related information including the retransmission start instruction command is created (S216), and the created related information is distributed to the receiving side (S217). Although not shown, the receiving side receives this retransmission start instruction and prepares to receive retransmission data. The transmitting side distributes the prepared retransmission file (S218). Subsequently, it is determined whether or not retransmission is to be performed again (S219). If the retransmission is to be performed, an event of a reception result output instruction is generated again (S220). If not, return to. The flow of the retransmission process on the transmitting side is as described above.

(2) Receiving Side Flow On the receiving side, when the multiplexed data stream starts to be received when power is turned on or the like (S301), preparations for receiving the related information 2 are performed as initialization processing (S301). S30
2). The related information 2 includes personal information such as contract information as described above.

When the initialization processing is completed and the relevant information 2 addressed to itself included in the multiplexed stream is received (S30)
3) Perform processing of related information 2 such as extraction of a work key (S)
304). Subsequently, when a channel is selected in order to receive a certain program (S305), preparation is made for reception of the related information 1 including information of application data to be transmitted in the program, and this is received (S306). If the channel has not been selected, return to.

When both the related information 1 and the related information 2 are received, it is next checked whether or not the command indicating the transmission mode included in the related information 1 or the related information 2 is a command indicating the retransmission processing ( S307). As a result of the check, if it is not a retransmission, a normal transmission process is performed (S308). In the case of retransmission, the processing shifts to retransmission processing.

In the retransmission process, it is first determined from the content of the command whether the instruction is a retransmission start instruction (S30).
9). If the received instruction is a retransmission start instruction, the process proceeds to retransmission data reception processing (S312). More on that later,
In the present embodiment, transmission of application data
The application data is divided into several blocks, and the blocks are further divided into a plurality of sections to transmit data in section units. Therefore, each time a section is received, it is determined whether the section is the last section of the last block of the retransmission data (S3).
13) If it is a section before the last section, it is checked whether or not each received section has an error (S314). If there is no error, processing such as outputting the received data to the outside is performed (S315). If there is an error, the section number and block number of the error and the identification number of the application data are recorded in the memory on the receiving side. . The processing of S309 and S312 to S316 is repeated until the reception of the last section of the last block is completed. When the reception is completed, it is determined whether or not all the blocks have been received normally (S317). If the instruction is not a retransmission start instruction in S309, it is a reception result output instruction (S309).
310), and outputs the reception result to the transmission side (S311), and returns to S309, which is the start position of the retransmission processing.

By performing processing on the transmitting side and the receiving side in the procedure described above, when data transmitted from the transmitting side in satellite communication and the system cannot be normally received by the receiving side, the data is transmitted from the transmitting side to the receiving side. Can be retransmitted, and the receiving side can reliably receive data.

[2.3 Configuration of Transmitting Station and Receiving Apparatus and Format of Retransmission Data] (1) Configuration of Transmitting Station and Receiving Apparatus Next, referring to FIGS. And the format of application data transmitted from the transmission side, and the embodiment of the present invention will be described in further detail.

FIG. 4 is a diagram showing the configuration of a communication system using the retransmission method of the present invention.

In FIG. 4, the transmitting station 106 divides application data such as video, audio, and various types of data output from the program management device 402 in a section data format described later into a certain data length in the framing device 405. Store in a time-division frame. In the case of normal transmission processing, the application data output from the program management device 402 need not be in the section data format. The operation of the program management device 402 and the framing device 405 will be described with reference to FIG.

FIG. 5 is a diagram for explaining a procedure for storing application data in a time-division frame.

First, the program management device 402 stores the application data 501 to be transmitted in a plurality of blocks A to
Divide into X. Then, the block is further divided into a plurality of sections C1 to CN.

Each section is stored in the data section 508 of the section data format 502. The section data format 502 is uniquely defined for implementing the present invention, and includes a data part 508 and a stored block number 50 to which the section C2 belongs.
3, the section number 504 in the block, the total number of sections 505 per block, and a cycle end flag 5 indicating whether the retransmission cycle is still continued or completed.
06, the last block number 507, and the like. It also detects errors in the data part,
An error correction code 509 for correction is added. The program management device 402 outputs each application data of video, audio, and data to the framing device 405 in this section data format.

The framing device 405 receives the section data format output from the program management device 402, stores it in a data length that can be stored in the information area 512 of the time-division frame of application data, and stores the section start identification. A flag 510 and a time-division frame identification number 511 are added to make a time-division frame 513 and output.

Returning to FIG. 4, the time division frame output from the framing device 405 is input to the multiplexing device 102.

On the other hand, the related information control device 401 controls the related information 1 creating device 403 and the related information 2 creating device 404 based on the information of the application data received from the program related information 402. The related information 2 creation device 404 generates a work key for encrypting the scramble key, and passes it to the related information 1 creation device 403. Further, the receiver has a database of a unique key (not shown) unique to the recipient, encrypts the work key created using the unique key, and outputs the encrypted work key in the related information 2. In the present invention, a command indicating the transmission mode is further included in the related information 2 and output.

The related information 1 creating device 403 generates a scramble key based on the control of the related information control device 401. Then, the generated scramble key is sent to the scramble device, and is encrypted using the work key received from the related information 2 creating device 404, and is output together with the information of each application data in the related information 1. At this time, in the present invention, the command indicating the transmission mode is also output in the related information 1. The command for specifying the transmission mode is added to the related information 1 and the related information 2.
Either or both may be used.

The related information output from the related information 1 creating device 403 and the related information 2 creating device 404 are time-divided into frames by the framing device 405, and the multiplexing device 10
2 is sent. The multiplexer 102 outputs a multiplexed data stream obtained by multiplexing time-division frames of video, audio, data, related information 1 and related information 2. The scrambler 103 scrambles the time-division frame of the application data included in the multiplexed data stream, which corresponds to the scramble key received from the related information 1 generator 403. The scrambled multiplexed stream ST1 is distributed to each receiving device.

Receiving apparatus 114 receives the multiplexed data stream transmitted from transmitting station 106, and descrambles the scrambled application data in descrambling section 110. Subsequently, the separation unit 111 refers to each time-division frame identification number,
Voice, data, data transmitted in the retransmission mode, related information 1, related information 2, and the like are separated. The related information 2 processing unit extracts the work key from the related information 2 using the unique key unique to the receiver, which is distributed in advance and stored in the memory management unit 416, and passes the work key to the related information processing unit 1, and also transfers the work key to the related information processing unit 1. It is stored in the memory management unit 416. The memory management unit 416 stores, in addition to the unique key and the work key, a personal identification number of the receiver, an identification number of a program that can be received by the receiver, and the like. In the related information 1 processing unit 417, the related information 1
Then, the information of the scramble key is taken out using the work key and passed to the descramble section 110. Related information 1 processing unit 41
7. If the related information 2 processing unit 415 includes a command for instructing retransmission processing in any of the related information, the related information 2 processing unit 415 extracts the command and sends it to the control unit 418. Control unit 41
8 transmits this instruction to the separation unit 111. The separation unit extracts the information area of the time-division frame of the received application data and stores the information area in a buffer (not shown) in the separation unit 111. Then, when the data for one section is received, the data is transmitted to the error detection unit 410. The start position of the section of the data stored in the buffer can be determined by referring to the section start identification flag 510 included in the time division frame 513 of the application data shown in FIG. The error is sent to the error detection unit 410 and an error is detected. If there is no error, the data is output from the receiving device via the data processing unit 411. If there is an error, the reception result is recorded in the memory 414, and the data with the error is discarded. Recorded as the reception result are the section number of the section having an error, the block number including the section, the time division frame identification number of the application data, and the like. The identification number of the application data is recorded in the memory 414 via the related information 1 processing unit 417, the control unit 418, and the data processing control unit 412. The data processing control unit 412 controls the error detection unit 410 and the data processing unit 411. When a reception result output instruction is sent from the transmitting station 106 in the related information 1 and the related information 2, the instruction is received via the control unit 418, and the reception result recorded in the memory 414 is received. The data is read and transmitted to the transmitting station 106 via the modem 413.

(2) Configuration of Data in Retransmission Processing Next, the configuration of application data transmitted and received between the transmitting station 106 and the receiving device 114 will be described.

First, the configuration of application data transmitted in the retransmission mode will be described with reference to FIG.

FIG. 6 is a diagram for explaining the configuration of application data transmitted in the retransmission mode and attribute information to be provided for the retransmission processing.

The application data to be transmitted from the transmitting station to the receiving station is composed of a plurality of blocks as described with reference to FIG. Here, blocks A, B, ...,
X. Each block is further composed of a plurality of sections. Here, an example is shown in which one block is composed of N sections. In this embodiment, each section has some attribute information. Then, the section is transmitted together with the attribute information. Attribute information is the block number that contains the section,
A section number in the block, a total number of sections per block, a cycle end flag indicating whether transmission of the application data is repeated or completed at this time, a last block number of the application data, and the like. Taking the section C2 of the block C in FIG. 6 as an example, the attribute information is that the block number is C, the section number is 2, the total number of sections is N, and the cycle end flag is that the application data is not repeatedly transmitted. The end and last block number is X.

Next, creation of a retransmission file will be described with reference to FIGS.

FIG. 7 is a diagram of a retransmission file created by the transmitting station based on a retransmission request from the receiving device.

FIG. 8 is a diagram of a continuous transmission file when application data is continuously transmitted.

FIG. 9 is an image diagram of the reception result stored in the reception result management table of the transmitting station.

The transmitting station 106 shown in FIG.
After sending the retransmission mode command in the relevant information to the server 14, the application data including the blocks A to X in FIG. 7 is transmitted. Then, the reception result output instruction command is transmitted in the related information. Receiving device 114 receives the reception result output command and sends the reception result to transmitting station 106. The transmitting station stores the reception result in a reception result management table (not shown) in the program management device 402. FIG. 9 shows a storage image diagram of the reception result management table. In the reception result management table, as shown in FIG. 9, an erroneous section number, block number, and identification number of a time-division frame of application data are managed in association with a receiver number. In FIG. 9, the recipient 1000 is in section 1 of block B of the application data P000.
First, the recipient 1001 receives the application data P00
0, block C, section 15 contains recipient 1002
Has detected an error in section 6 of block E of application data P000, and receiver 1003 has detected an error in section 10 of block F of application data P000.

The transmitting station creates a retransmission file 701 consisting of blocks B, C, E and F as shown in FIG. 7 based on the reception results stored in the reception result management table. The transmission of the retransmission file 701 is the same as the transmission of the application data in the retransmission mode, and is transmitted together with the attribute information for each section. FIG. 7 shows the attribute information 7 of the block C / section 15 of the retransmission file 701.
02 and attribute information 703 of block F / section 10
Is shown.

In addition to creating the retransmission file 701 from the erroneous block as described above and sending it once, a series of application data may be repeated a plurality of times for retransmission (hereinafter referred to as continuous transmission). At the time of continuous transmission, a series of blocks of application data, A to X, are repeatedly transmitted as shown in FIG. FIG. 8 shows a continuous transmission file 801 when transmitting twice. In the section within the blocks A to X sent for the first time, the cycle end flag continues, and the blocks A to X sent for the second time
, The cycle end flag ends.

The transmitting station 106 shown in FIG.
After transmitting the retransmission start instruction command included in the related information to 14, the retransmission file 701 or the continuous transmission file 801 is transmitted. Receiving apparatus 144 receives the retransmission start instruction command and prepares for retransmission reception, and then receives retransmission data stored and transmitted in a time division frame in section units. Then, referring to the section data included in the information area of each time-division frame shown in FIG. 5 and the attribute information such as the block number and the section number, if the section has not been correctly received due to an earlier error. For example, the reception processing is performed in the retransmission mode. If it is determined that all the retransmission data to be received has been received, the receiving apparatus ends the retransmission mode and returns to the normal transmission processing mode.

[2.4 Format of Related Information Used for Retransmission Control] Next, a transmission format of a command indicating a transmission mode will be described with reference to FIGS. As described above, the transmission mode instruction command is stored in the related information 1 or the related information 2 and transmitted.

FIG. 10 is a format diagram of the related information 1 when transmitting a command indicating a transmission mode using the related information 1.

FIGS. 11 and 12 are format diagrams of the related information 2 when transmitting a command indicating a transmission mode using the related information 2. FIG.

When transmitting a command indicating a transmission mode using the related information 1, as shown in FIG. 10, the transmission instruction command is placed at a predetermined position in the information area 1005 of the time division frame 1006 of the related information 1. 1002 is stored. The transmission instruction command expresses four patterns of the command for instructing the three types of retransmission processing and the command for instructing the normal transmission processing.
is necessary. In addition, the information area includes program identification information A1003, which is identification information of application data targeted by the related information 1, scramble key information 1004, and the like. Here, the program identification information A1003 is an event identification number assigned to each program.

Next, a case where a command indicating a transmission mode is transmitted using the related information 2 will be described.

FIG. 11 is a diagram of a time-division frame of the related information 2. The command instructing the transmission mode is stored at a predetermined position in the information area 1105 of the time-division frame 1106. In the information area, the related information 2
, And a program identification information B1104 which is identification information of application data. The program identification number B1104 includes an event identification number assigned to each program and an application identification number assigned to each application data. FIG. 11 shows a case where a retransmission mode instruction command is transmitted among three types of commands for instructing retransmission processing. The transmission instruction command area 1103 stores a retransmission mode instruction command.

On the other hand, a reception result output instruction, a retransmission start instruction,
When transmitting a command instructing normal transmission processing, the program identification information B1104 is not added to the related information 2. FIG. 12 shows the format in this case. A reception result output instruction, a retransmission start instruction, and a command for instructing normal transmission processing are stored in the transmission instruction command area 1203.

The command instructing the retransmission process from the transmitting station to the receiving device is stored in the related information 1 or the related information 2 in the format described above and transmitted.

[2.5 Another Example of Configuration of Receiving Apparatus] Finally, another example of the configuration of the receiving apparatus will be described with reference to FIG.

FIG. 13 is a system configuration diagram in the case where the receiving device is constituted by a security module unit in the receiving unit.

In FIG. 13, the related information 2 processing unit 415, the related information 1 processing unit 417, and the memory management unit 41 shown in FIG.
6 is made independent as a security module unit 1302, and other components constitute a receiver unit 1301. A security module unit interface processing unit 1303 and a receiver unit interface processing unit 1304 are provided between the receiver unit 1301 and the security module unit 1302. The other configuration is the same as that described in FIG. 4, and the same reference numerals are given and the description is omitted.

As described above, when the receiving apparatus is constituted by the security module section 1302 and the receiver section 1301,
The flexibility of the hardware configuration of the receiving device can be provided, and the expandability of the entire system increases. For example, if the function of the security module unit 1302 is provided in an IC card so as to be portable, the receiver 1301 can be used outside the home.
Data can be received wherever there is. A PC that incorporates the function of the receiver unit 1301 into a personal computer (hereinafter, referred to as a PC)
If it is realized by a board, this PC board can be incorporated into a PC and a receiving antenna can be prepared to immediately receive data. Also, in the case of receiving by a PC, if the security module unit is carried as an IC card, data can be received anywhere where there is a PC or an IC card compatible receiver capable of receiving data.

[0072]

According to the retransmission method of the present invention and the communication system, transmitting apparatus and receiving apparatus using the same, satellite communication,
In cable TV and terrestrial communications, if the data transmitted from the transmitting side is not received correctly by the receiving side, the data can be retransmitted from the transmitting side and the receiving side can receive the data reliably. Becomes

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a general satellite communication system.

FIG. 2 is a flowchart of a transmission side process of the retransmission method of the present invention.

FIG. 3 is a flowchart of a receiving side process of the retransmission method of the present invention.

FIG. 4 is a diagram showing a configuration of a communication system using the retransmission method of the present invention.

FIG. 5 is a diagram illustrating a procedure for storing application data in a time-division frame.

FIG. 6 is a diagram for explaining a configuration of application data to be transmitted in a retransmission mode and attribute information added for retransmission processing.

FIG. 7 is a diagram of a retransmission file created by a transmitting station based on a retransmission request from a receiving device.

FIG. 8 is a diagram of a continuous transmission file when application data is continuously transmitted.

FIG. 9 is an image diagram of a reception result stored in a reception result management table of a transmitting station.

FIG. 10 is a format diagram of related information 1 when a command indicating a transmission mode is transmitted.

FIG. 11 is a format diagram of related information 2 when a command indicating a transmission mode is transmitted.

FIG. 12 is a format diagram of related information 2 when a command indicating a transmission mode is transmitted.

FIG. 13 is a configuration diagram of a system in a case where the receiving device is configured by a security module unit in the receiving unit.

[Explanation of symbols]

101: related information generating device, 102: multiplexing device, 10
3 ... Scramble device, 104 ... Transmission device, 105 ... Transmission antenna, 106 ... Transmission station, 107 ... Satellite, 108 ...
Receiving antenna, 109 receiving section, 110 descrambling section, 111 separating section, ST1 data stream, 4
01 ... related information control device, 402 ... program management device, 40
3 ... related information 1 creating device, 404 ... related information 2 creating device, 405 ... framing device, 410 ... error detecting unit, 4
11 data processing unit, 412 data processing control unit, 41
3. Modem, 414 memory, 416 memory management unit
415: related information 2 processing section, 417: related information 1 processing section, 418 ... control section, 419 ... ground line, 501 ... application data, 502 ... section data format, 503 ... block number, 504 ... section number, 505 ... Total number of sections, 506: cycle end flag, 507: last block number, 508: data part, 509: error correction code, 510: section start identification flag, 511, 1001, 1101, 1201: time division identification frame identification number, 512 ... information area, 51
3,1006,1106,1205 ... time-division frame,
701: retransmission file, 702, 703: section attribute information, 801: continuous transmission file, 802, 803, 8
04,805... Section attribute information, 1002, 11
03, 1203 ... transmission instruction command, 1003 ... program identification information A, 1004 ... scramble key information, 1005
... Information area of related information 1, 1102, 1202. Recipient number, 1104. Program identification information B, 1105, 1204
... information area of related information 2, 1300 ... receiving device, 130
DESCRIPTION OF SYMBOLS 1 ... Receiver part, 1302 ... Security module part, 1303 ... Security module part interface processing part, 1304 ... Receiver part interface processing part.

Claims (8)

[Claims] 1. A data transmission method for time-division multiplexing at least one application data and related information of the application data and transmitting the multiplexed data from a transmitting side to a plurality of receiving sides, wherein the transmitting side transmits the related information A data transmission method characterized by adding information for controlling a receiving process of application data on a receiving side to transmit. 2. A transmission side, after adding reception processing control information for instructing data confirmation to the related information and transmitting to the reception side, divides the application data into a plurality of blocks, and divides each block into a plurality of blocks. Divided into sections
The section attribute information is added to each section and transmitted to the receiving side. The receiving side checks whether or not the received application data has been successfully received for each section and failed to receive the data correctly. 2. The data transmission method according to claim 1, wherein the attribute information is recorded as a reception result for the section. 3. When the transmission side has completed transmission of all sections of the application data, the transmission side adds reception processing control information for instructing output of a reception result to the related information, and transmits the related information to the reception side. 3. The data transmission method according to claim 2, wherein the recorded reception result is transmitted to a transmission side in response to an instruction to output the reception result. 4. A transmitting side creates a retransmission file composed of application data that has not been normally received based on the reception result sent from the receiving side, and notifies the related information of the start of transmission of the retransmission file. 4. The data transmission method according to claim 3, wherein the retransmission file is transmitted to the receiving side after adding control information to be transmitted. 5. A receiving apparatus for receiving a multiplexed data stream obtained by time-division multiplexing at least one application data and related information of the application data, wherein each application data of the received multiplexed data stream is A separating unit that separates related information; a related information processing unit that extracts information about application data and information that controls reception processing from the separated related information; and a controlling unit that controls the separating unit based on the information that is extracted by the related information processing unit. A control unit that performs error detection on received application data; a memory that records results detected by the error detection unit; reading and writing of detection results in the memory; and data control that controls the error detection unit. And a receiving unit. 6. A receiver unit having the separation unit, the control unit, the error detection unit, a memory, and a data control unit, and the related information processing unit, wherein the receiver unit and the related information processing unit are interface units. The receiving apparatus according to claim 5, wherein the receiving apparatus is configured to be connected and separable. 7. A transmitting apparatus for time-division multiplexing at least one application data and related information including information on the application data and transmitting the multiplexed data to a plurality of receiving apparatuses, wherein the transmitting apparatus stores at least one application data. An application data management unit that manages the application data, a related information generation unit that generates the related information, and a multiplexing unit that multiplexes the application data output from the application data management unit and the related information generated by the related information generation unit. A transmitting device, wherein the related information generating unit adds information for controlling a receiving process in the receiving device to the generated related information. 8. A transmission apparatus comprising at least one receiving apparatus, at least one application data and related information including information on the application data are time-division multiplexed and transmitted from the transmitting apparatus to a plurality of receiving apparatuses. A communication system for transmitting and transmitting a reception result of application data from a receiving device to a transmitting device, wherein the transmitting device generates an application data management unit that stores and manages at least one application data, and generates the related information. A related information generating unit for adding and outputting information for controlling a receiving process in the receiving device, and multiplexing the application data output from the application data managing unit and the related information generated by the related information generating unit, Device for receiving multiplexed data stream A multiplexing unit that transmits the application data and related information of the received multiplexed data stream; and information that controls application processing and reception processing from the separated related information. A related information processing unit for extracting the application data, a control unit for controlling the separation unit based on the information extracted by the related information processing unit, an error detection unit for detecting an error in the received application data, and an error detection unit. A communication system comprising: a memory that records a result; and a data control unit that reads and writes a detection result in the memory and controls the error detection unit.