Patent ID: 7668250

Claim:
A receiver for trellis decoding a stream of symbols selected from a full symbol alphabet separable into a plurality of component restricted symbol alphabets, each said component restricted symbol alphabets having increased Euclidean distance compared to said full symbol alphabet between respective symbols thereof at least some of which symbols are selected from said plurality of restricted symbol alphabets in accordance with a pattern so as to generate more robust symbol coding, said stream of symbols being Reed-Solomon forward-error-correction coded before being convolutionally interleaved and subsequently trellis coded to generate time-dependent trellis codes in which different sets of symbol codes are precluded at prescribed times so as to increase the Hamming distances between possible trellis codes, said receiver comprising: apparatus for determining which data segments in said stream of symbols before their convolutional interleaving contained symbols selected from said plurality of restricted symbol alphabets in accordance with said pattern, and for supplying indications of when said data segments occur; a trellis decoder connected for trellis decoding said stream of symbols to generate a trellis decoding result; a de-interleaver connected for de-interleaving said trellis decoding result to reproduce said stream of symbols including said more robust symbol coding; a two-data-segments-to-one data compressor connected for selectively compressing said stream of symbols including said more robust symbol coding reproduced from said de-interleaver, said selective compressing being done responsive to said indications of the occurrence of data segments in said stream of symbols that before their convolutional interleaving contained symbols selected from said plurality of restricted symbol alphabets in accordance with said pattern; and Reed-Solomon decoding apparatus connected for receiving said stream of symbols after being selectively compressed by said two-data-segments-to-one data compressor, said Reed-Solomon decoding apparatus for decoding lateral Reed-Solomon forward-error-correction coding.