Concatenated Coded Modulation for Optical Communications Systems
01 January 2010
We study the use of trellis-coded modulation (TCM) as an inner code in combination with outer block codes that use hard decision decoding. As outer codes we consider a byte-oriented (255,239) Reed Solomon code and a block code that comprises two interleaved extended three-error correcting Bose Chaudhuri Hocquenghem codes of length 1020 each. Simulations show that a maximum net coding gain improvement of 2.85 dB and 1.13 dB, respectively, can be achieved with the considered TCM inner codes for an output bit error rate of 10-3.
