TRELLIS CODES FOR (1,K) E(2)PR4ML WITH SQUARED DISTANCE-18

Finite truncation depth codes are obtained using periodically pruned m odule N trellises. One approach uses a runlength limited (d,k) = (1,7) code with rate R = 2/3 as the underlying code. Another approach which results in a lower complexity detector trellis uses a rate R = 3/5 sl iding-block code that prohibits NRZI '10001' and adheres to a (d, k) = (1,8) constraint. The design of the module N trellis is described, an d sufficient conditions for finite truncation depth are developed and applied to obtain several codes.