JPH0548579A - Broadcasting communication processor - Google Patents

Abstract

PURPOSE:To make economical recovery of a receiving data error in broadcasting communication possible by sequentially making inquiry until a predetermined terminal that correctly received data is detected and by receiving retransmission from the terminal if there is correctly received data. CONSTITUTION:Broadcasting receiving section 1 receives broadcasting communication data and stores it as temporarily received data 6, and in accordance with codes of data 6 executes a predetermined error inspection. Further, when an error is detected, the broadcasting receiving section refers to terminal table 3, sequentially calls other terminals 5 connected to this broadcasting communication processor prior to a communication means 4, and in accordance with a predetermined protocol makes inquiry to terminals 5 whether the last broadcasting communication data has been correctly received. Furthermore, if there is a terminal received correctly, the processor receives received data from the terminal, and stores it as received data 7. With this, error recovery by retransmission can be economically done.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention obtains correct received data when there is an error in the received data at the receiving station of the broadcast communication when the broadcast communication is carried out to many terminals by satellite communication or the like. The present invention relates to a broadcast communication processing device that can perform.

[0002]

2. Description of the Related Art 1 By transmitting data from a transmitting station to a communication satellite, relaying it on the satellite and broadcasting it to the ground, a large number of terminal stations on the ground simultaneously broadcast the same data. It is well known that broadcast communication in the form of reception is possible.

[0003] In satellite communication, the rate of occurrence of data transmission errors due to rainfall or the like is relatively high. Therefore, in order to practically enable data transmission with low redundancy,
It is necessary to have an appropriate error detection capability and be able to obtain correct data (error recovery) by some method when an error is detected.

In general data transmission, as a relatively simple method for error recovery, when data is constructed by an appropriate error detection code and transmitted, and an error is detected on the receiving side,
A method of requesting retransmission from the receiving side to the transmitting side is used.

As a method of retransmission in the case of broadcast communication in which a plurality of terminals are broadcast at the same time as described above, a terminal which has detected an error retransmits from a transmitting station by communication through another terrestrial communication line or the like. There is a way to get.

However, when this retransmission method is used, as the number of terminals increases, the cost of the equipment for retransmission by the terrestrial line becomes non-negligible, and the economic merit of using satellite communication is lost. there is a possibility.

The present invention relates to broadcast communication by satellite communication,
A broadcast communication processing device capable of economically performing error recovery by retransmission.

[0008]

FIG. 1 is a block diagram showing the configuration of the present invention. The figure shows the configuration of a broadcast communication processing device, which is a terminal for receiving broadcast communication, and which is a broadcast receiving unit 1
And a recovery processing unit 2.

The broadcast receiving unit 1 receives the data of the broadcast communication, identifies whether or not there is an error in the received data by a predetermined error detection process, and when an error is detected in the received data, It requests the recovery processing unit 2 for processing.

The recovery processing unit 2 has a terminal table 3,
The terminal table 3 is connected to the communication means 4 and holds necessary connection control information for communication with another predetermined terminal 5 communicated by the communication means 4, and the communication means 4 follows the terminal table 3 according to the terminal table 3. By sequentially communicating with each of the other terminals 5, the other one terminal having no error in the received data of the broadcast communication is detected, and a copy of the received data of the detected other terminal is transmitted by the communication means 4. To receive.

[0011]

According to the broadcast communication processing device of the present invention, each terminal registers, for example, one or several terminals relatively close to each other in the terminal table, and when there is an error in the received data of the broadcast communication, These terminals in the terminal table are sequentially inquired until there is a terminal that correctly received the data, and if there is correct received data, the terminal receives the retransmission.

Therefore, no matter how the number of terminals increases,
It is possible to provide an economical retransmission function without the retransmission requests being concentrated on the transmitting station and causing an excessive load.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 3 is a diagram showing an example of the flow of processing of the present invention. In FIG. It is stored and in a processing step 11, a predetermined error check is executed according to the code of the received data 6.

If there is no error as a result, processing step 12
After that, the data is stored in the file as the received data 7 in the processing step 13, and the recovery processing unit 2 is notified of the normal reception.

If an error is detected, the recovery processing unit 2 requests the recovery processing unit 2 to perform an error recovery process in the processing step 14, so the recovery processing unit 2 refers to the terminal table 3 in the processing step 15 so that the communication means 4 can operate. The other terminals 5 connected earlier are sequentially called, and an inquiry is made as to whether or not the last broadcast communication has been normally received according to a predetermined protocol.

For example, when the other terminal 5 has the same configuration and the recovery processing unit 2 receives this inquiry, the inquiry state of the reception status “normal reception” or “error reception” received from the broadcast reception unit 1 is sent. To answer.

For the communication means 4, for example, a subscriber telephone network is used, and in that case, the terminal table 3 is a table having the items of priority and terminal telephone number as shown in FIG.

According to the priority of the terminal table 3, the recovery processing unit 2 calls the terminal with the telephone number registered in that section, disconnects the connection if the reply from the partner terminal is "error reception", and Move on to calling the terminal of priority.

In the example of the terminal table shown in FIG. 2, by registering the center (transmission station) with the lowest priority,
When all the terminals in the vicinity are "error reception", the center is requested to retransmit.

In this way, if there is a normal reception terminal,
After processing step 16, in processing step 17, the received data is transferred from the terminal, and in processing step 18, it is stored in the file as received data 7.

If any of the terminals has received an error, at step 19 a retransmission is received from the center of the transmitting station and stored in a file.

[0022]

As is apparent from the above description, according to the present invention, there is a remarkable industrial effect that error recovery by retransmission can be economically performed in broadcast communication such as satellite communication.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of the present invention.

FIG. 2 is a diagram illustrating a terminal table.

FIG. 3 is a process flow chart of the present invention.

[Explanation of symbols]

 1 Broadcast Receiver 2 Recovery Processor 3 Terminal Table 4 Communication Means 5 Other Terminals 10-19 Processing Steps

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Taizo Kinoshita 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Fujitsu Limited

Claims (1)

[Claims] 1. A terminal for receiving broadcast communication, comprising a broadcast receiving unit (1) and a recovery processing unit (2), the broadcast receiving unit (1) Upon receiving the data, the presence or absence of an error in the received data is identified by a predetermined error detection process, and when an error is detected in the received data, the recovery processing unit (2) is requested to perform processing, The recovery processing unit (2) has a terminal table (3) and has a communication means.
(4), and the terminal table (3) holds necessary connection control information for communication with the predetermined other terminal communicated by the communication means (4). ), Sequentially communicates with each of the other terminals according to the terminal table (3), detects the other one terminal having no error in the received data of the broadcast communication, and detects the other terminal of the detected other terminals. The communication means is a copy of the received data.
A broadcast communication processing device, characterized in that it is configured to receive by (4).