Patent ID: 7770093

Claim:
A decoding apparatus configured to decode first symbols received from a channel, wherein the first symbols correspond to output symbols transmitted onto the channel by an encoder system, wherein the encoder system is configured to perform an outer encoding on source data in order to generate first data, and to perform an inner trellis coded modulation (TCM) on an interleaved version of the first data to generate the output symbols, the decoding apparatus comprising: an inner soft-input soft-output (SISO) module configured to compute first feedforward information based on input information and on first feedback information, wherein the input information is derived from the first symbols received from the encoder system, wherein the inner SISO module is configured to compute the first feedforward information based on an inner trellis defined by said inner TCM of the encoder system; a fill and multiplex (FAM) unit configured to generate augmented information by interleaving zero bits with bits of a deinterleaved version of the first feedforward information; an outer SISO module configured to compute output information and second feedback information based on the augmented information, wherein the outer SISO module is configured to compute the output information and the second feedback information based on an outer trellis defined by the outer encoding of the encoding system; and a puncture and demultiplex (PAD) unit configured to puncture the second feedback information according to a puncturing pattern, in order to generate punctured feedback information, wherein the first feedback information is an interleaved version of the punctured feedback information; wherein the inner TCM of the encoder system includes an inner encoding and a mapping, wherein the inner encoding encodes the interleaved version of the first data to generate intermediate data according to a rate 1 recursive code, wherein the mapping generates the output symbols of the inner TCM from the intermediate data according to a first map, wherein the rate 1 recursive code and the first map maximize the effective free Euclidean distance of the inner TCM.