Matched Design Method for Concatenated Trellis-Coded Modulation

A new design method,which is referred to as the matched design method, for concatenated trelliscoded modulation(TCM) is presented. Most of the conventional concatenated TCM employs TCM designed by maximizing the minimum squared Euclidean free distance,dfree. With the matched design method, we maximize d1(t) instead of d 2 free, where d1(t) is the e ective minimum squared Euclidean distance(MSED) when the outer code has a t-error correcting capability. The e ective MSED is derived from the Euclidean/Hamming(E/H) joint weight distribution of terminated TCM. The new classes of 2-dimensional(2D) codes are found by a computer search. Under the performance measures of the e ective MSED or the e ective multiplicity, these codes are superior to the conventional codes such as the Ungerboeck's codes when those are used as an inner code.