Patent ID: 7243294

Claim:
An encoding system configured to output symbols, comprising: an outer coder, configured to receive data to be coded, and producing outer coded data as an output; an interleaver, coupled to receive said outer coded data as an input, and to permute said outer coded data to produce interleaved data; a recursive rate m/m inner coder, receiving said interleaved data, and coding m bits of said interleaved data to produce m bits of inner coded output data according to an inner code, wherein said recursive rate m/m inner coder has a structure which facilitates iterative decoding of said symbols at a decoder; a mapping element, receiving an output of said recursive rate m/m inner coder, and assigning said m output bits to a first of said symbols according to a mapping; wherein said recursive rate m/m inner coder and said mapping element are selected to maximize the effective free Euclidean distance of a trellis coded modulator formed from said recursive rate m/m inner coder and said mapping element.