多进制正交扩频加卷积编码体制性能分析  

Analysis of Performances of M-ary Orthogonal Code Spread Spectrum System with Convolutional Code

作　　者：王丽韫[1] 王军[2] 王育红[1] 

机构地区：[1]中国电子科技集团公司第五十四研究所,河北石家庄050081 [2]中国电子科技集团公司第十三研究所,河北石家庄050081

出　　处：《无线电工程》2008年第10期20-22,共3页Radio Engineering

摘　　要：介绍了多进制正交扩频加卷积编码体制的发射端和接收端的原理,给出了多进制正交扩频系统的理论误比特率性能,针对接收端需要对多路匹配滤波器输出信号进行最大值判决,以利于后级的信道译码,从对数似然比(LLR)出发,提出了一种适用于多进制正交扩频系统的次最优的软信息提取方法。对在AWGN信道中多进制正交扩频系统性能进行了MATLAB仿真。结果表明,多进制正交扩频加卷积编码体制不但能有效地解决带宽与处理增益之间的矛盾,还可以获得比直扩系统加卷积编码更高的增益。The principles of transmitter and receiver of M-ary orthogonal code spread spectrum system are introduced. The theoretical performances of M-ary orthogonal code spread spectrum system are given. Based on the Log-likelihood Ratio（LLR）, a suboptimal softinformation extracting scheme in the M-ary orthogonal code spread spectrum system is proposed for the receiver needs to perform the maximal value decision to multiple matched filter output signals before channel decoding. The performances of the system in AWGN channel axe simulated with MATLAB. The results indicate that M-ary orthogonal code spread spectrum system is not only an effective scheme to solve contradiction between bandwidth and spread spectrum gain but also is superior to the direct sequence spread spectrum system on spread spectrum gain.

关 键 词：多进制正交扩频 卷积编码 软判决 

分 类 号：TN914[电子电信—通信与信息系统]