基对称扩展信道极化算法及其在OFDM水声通信系统中的应用  

Base Symmetric Spread Channel Polarization Algorithm and Its Application in OFDM Underwater Acoustic Communication

作　　者：杨斌斌 鄢社锋[1,2] YANG Binbin;YAN Shefeng(Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院声学研究所,北京100190 [2]中国科学院大学,北京100049

出　　处：《信号处理》2021年第7期1133-1141,共9页Journal of Signal Processing

基　　金：国家自然科学基金项目资助(61725106)。

摘　　要：针对水声通信系统中低密度校验(Low Density Parity Check,LDPC)码存在的译码复杂度高和译码错误平层问题,设计了基于极化码编码的水声通信系统,并针对水声信道的极化问题提出了新的基对称扩展极化权重(Polarization Weight,PW)信道极化法。该算法通过PW高阶基计算各个子信道的极化权重,实现了独立于信道状态的信道极化,解决了传统Polar码编码稳健性差和依赖信道状态的问题。理论研究和仿真结果表明,与传统信道极化方法相比,改进的PW方法具有更稳定的信道极化结果。将该方法应用于正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)水声通信系统,与现有的LDPC编码方法相比,基于改进的PW极化码具有更低的通信误码率和译码复杂度,且不存在译码错误平层。Aiming at the problem of high decoding complexity and error floor of LDPC code in underwater acoustic communication system,a polar coded underwater communication system is designed,and a base symmetric spread channel polarization algorithm is proposed for underwater multipath channel polarization.By introducing high order base of PW,modified PW solved the problems of poor robustness and channel state dependence of polar code.Theoretical analysis and simulation results show that the modified PW method has stronger robustness in channel polarization than traditional polarization method.The proposed method is applied to OFDM underwater acoustic communication system,the designed Polar-OFDM system improves the performance in terms of the bit error rate(BER)and decoding complexity sufficiently in comparison with LDPC,and without error floor.

关 键 词：极化权重 极化码 正交频分复用 水声通信 

分 类 号：TN929.3[电子电信—通信与信息系统]