Multi-rate transmission apparatus

A multi-rate transmission apparatus in which a coding ratio is varied in accordance with an input modulation operation mode to allow a transmission operation with a single input clock signal for any input modulation mode, comprising:

• data processing means for reading in data having a bit width suitable for a modulation system corresponding to the input modulation mode;
• coding means for performing coding processing parallely for the data read in by said data processing means;
• and
• transmission means for transmitting the data, for which the coding processing has been performed, in accordance with the modulation system and the varied coding ratio,
• wherein said coding means includes:
• a register set for storing data of n-bit strings, n being a natural number;
• a plurality of convolution coding circuits for fetching the data of n-bit strings from said register set and performing convolution processing for the data of n-bit strings in a unit of n-bit strings fixed;
• a puncture circuit for performing puncture processing for coding results outputted from said plurality of convolution coding circuits and outputting coded data;
• and
• a data discrimination circuit for discriminating bits corresponding to the coded data outputted from said puncture circuit.