Evaluation of New Trellis Coded Modulation Schemes for Nextage Mobile Communications

提出了一种新的级联格状编码调制设计方法--匹配设计法。传统的级联码大多采用最大化最小平方欧几里德自由距离d^2_e设计的最小平方欧几里德距离，在匹配设计方法下，我们将d^2_(T)最大化而不是d^2_e，其中d^2_(T)是外码具有t-纠错能力时的有效最小平方欧氏距离(MSED)。有效的MSED由终止的中医药的欧几里得/汉明(E/H)联合重量分布得到，通过计算机搜索找到了新的二维码。在有效MSED或有效复数的性能指标下，这些码在作为内码时优于传统的Ungerboeck码。

A new design method, which is referred to as the matched design method, for concatenated trellis-coded modulation (TCM) is presented. Most of the conventional concatenated TCM employs TCM designed by maximizing the minimum squared Euclidean free distance, d^2_e. With the matched design method, we maximize d^2_ (t) instead of d^2_e, where d^2_ (t) is the effective minimum squared Euclidean distance (MSED) when the outer code has a t-error correcting capability. The effective 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 effective MSED or the effective multiplicity, these codes are superior to the conventional codes such as the Ungerboeck's codes when those are used as an inner code.