摘要
相位调制在载波提取时存在的不同程度的相位模糊,会导致网格编码调制系统的性能出现明显下降。设计对相位变化不敏感的TCM纠错码,可以在不增加额外信息的情况下克服相位模糊。一种基于网格旋转不变性的构造方法,可以避免复杂的计算机搜索算法,轻松构造出满足TCM分支转移条件,且对任意角度旋转均不敏感的MPSK旋转不变码。给出了16状态TCM-8PSK旋转不变码的设计实例。
Phase-ambiguity that largely reduces transmission performances can hardly be avoided when extracting carriers from a TCMMPSK signal.Rotationally invariant trellis code is a powerful method to overcome phase-ambiguity without extra information. A new method based on rotationally invariant trellis can easily generate fully rotationally invariant TCM-MPSK code without complicated computer search. An example of 16-state 8PSK trellis code is also provided.
出处
《无线电通信技术》
2008年第5期16-17,42,共3页
Radio Communications Technology
关键词
网格编码调制
旋转不变码
MPSK
相位模糊
trellis coded modulation
rotationally invariant trellis codes
MPSK
phase ambiguity
