一种新的双多进制正交扩频调制信号的差分解调算法  

A New Differential Demodulation Algorithm in Dual N-ary Orthogonal Spread System

作　　者：张玉明[1] 程云鹏[1] 徐友云[1] 

机构地区：[1]解放军理工大学通信工程学院,南京210007

出　　处：《上海交通大学学报》2007年第5期729-734,共6页Journal of Shanghai Jiaotong University

基　　金：国家重点基础研究发展规划(973)项目(5130601)

摘　　要：研究了具有高频谱效率的双多进制正交扩频调制系统,提出了差分解调输出比特信息的后验概率(APP)算法,该算法能使整个系统获得相当的增益.为了降低运算的复杂度给出了简化算法,并讨论了简化算法的优化策略.在加性高斯白噪声(AWGN)和多径Rayleigh衰落信道下进行的仿真结果表明,所提算法是有效的,采用优化的简化算法性能可以进一步逼近APP算法.This paper investigated the system of dual N-ary orthogonal spread spectrum which is bandwidth efficient modulation, and proposed an APP （a posteriori probability） algorithm for computing bit information metric of M-ary differential phase demodulation. The proposed algorithm greatly improves the whole system performance. A simplified APP algorithm was presented in order to decrease the complexity of computing, and the optimal strategy of the simplified algorithm was discussed. The simulation results show that the effectiveness of the proposed algorithm and the performance of the optimal algorithm can approach the APP algorithm.

关 键 词：TURBO码 正交码 后验概率算法 

分 类 号：TN929.5[电子电信—通信与信息系统]