摘要
本文主要研究网格编码调制(TOM)好码的搜索问题,对Ungerboeck中的算法进行验证并修正了一些规则,获得了更完整的结果。搜索结果表明,对一定约束长度和调制方式,具有最大欧氏自由距的TCM好码有多个,文中给出了具有最简编码器结构的TCM好码。本文还对采用最小编码器结构的TCM码进行了搜索。发现对于由相同一致校验矩阵衍生得到的系统TCM码和最小TCM码,在某些情况下前者不能达到最大欧氏自由距,而后者能够达到。
This paper concentrates on search of powerful codes for TCM. We verify and modify the search procedure developed by Ungerboeck[1]. More sophisticated results are obtained. The results indicate that the best TCM codes with maximum free Euclidian Distance (ED) are more than one for a given constraint length and modulation scheme. The TCM codes with the simplest structure are listed in this paper. We also search the powerful TCM codes for minimal encoders, and find that in some cases the minimal encoders can reach the maximum free ED while the systematic encoders with the same parity-check polynomials can not.
出处
《电子学报》
EI
CAS
CSCD
北大核心
1991年第6期65-72,共8页
Acta Electronica Sinica
