水声DS-CDMA通信中多相位假设码片速率自适应判决反馈均衡算法研究  

A study of chip rate phase hypothesis adaptive decision feedback equalization for DS-CDMA underwater acoustic communication

作　　者：王晋兴[1,2] 朱敏[1] 

机构地区：[1]中国科学院声学研究所,北京100190 [2]中国科学院研究生院,北京100190

出　　处：《声学技术》2009年第3期212-216,共5页Technical Acoustics

基　　金：国家863计划(2006AA09Z212)

摘　　要：研究了直接序列扩频码分复用(DS-CDMA)通信中基于多相位假设的码片速率自适应判决反馈均衡算法。水声信道的衰落和多普勒频移会严重影响扩频信号的相关特性,需要在做解扩频之前进行多普勒频移补偿和信道自适应均衡。将空间分集-多普勒频移补偿-自最佳自适应判决反馈均衡算法应用到DS-CDMA通信中,提出一种基于多相位假设的码片速率自适应判决反馈均衡算法,并用实际的千岛湖实验数据和仿真数据对算法性能进行了分析。结果表明算法以增加计算复杂性为代价显著提高了DS-CDMA通信性能,在复杂快变的多途和多普勒频移条件下可以保证低的误符号率,在低信噪比条件下能够稳定工作,总体性能良好。A study of chip rate phase hypothesis adaptive decision feedback equalization algorithm for DS-CDMA underwater acoustic communication is presented. Underwater acoustic communication channel is a delay-Doppler double spreading channel. Fading and Doppler spreading severely degrade the correlation characteristic of the spread spectrum signals, so Doppler shift compensation and equalization are needed before decoding. By applying Space diversity-Doppler compensation-Fast Self-Optimized adaptive decision feedback equalization algorithm into DS-CDMA communication, a chip rate phase hypothesis adaptive decision feedback equalization algorithm for DS-CDMA underwater acoustic communication is proposed and its performance is analyzed with real lake trial data and simulation data. At the price of computational complexity, the algorithm dramatically improves DS-CDMA communication qual- ity. Very low symbol error rate is achieved under fast changing multi-path and Doppler shift condition, and the equalizer is stable under low SNR. The overall performance of this algorithm is satisfactory.

关 键 词：水声通信 空间分集 直接序列扩频 码分复用 码片速率判决反馈均衡 相位假设 

分 类 号：TN911.7[电子电信—通信与信息系统]