Method and apparatus for digital data transmission with automatic repeat request

A method of transmitting digital data with automatic repeat requests (ARQ), and with error detecting or correcting encoding being used on the transmitted blocks, and with a "confidence flag" (3) being provided representative of the reliability of decoding, the method being characterized in that it consists in providing an additional location in each frame to be transmitted, said additional location being large enough for it to be possible, in the event of delay reaching a predetermined value (r) judged to be excessive and due to repeat transmissions, to absorb this excessive delay by transmitting a plurality (n) of information blocks simultaneously in a single frame instead of transmitting only one at a time as when the delay is not excessive, such a frame comprising a plurality of information blocks thus comprising, prior to encoding, at least:

• a conventional frame locking word (MVT);
• a command block (COM) which includes the information required by the repeat transmission protocol, which information includes a mention (C) of the number (n) of useful information blocks being transmitted simultaneously in the frame, namely a single block when the delay (r) is zero or not excessive, and two or more blocks (n) when the delay (r) is judged to be excessive;
• and
• an information block (INFO) which includes, inter alia, useful information bits per se, with the size of the information block being sufficient, in the event of a delay (r) judged to be excessive, to contain two or more (n) successive blocks of useful information, each of which would otherwise have been transmitted in a respective frame.