基于LDPC码的水声扩频通信性能仿真  

Performance Simulation of Underwater Acoustic Spread Spectrum Communication Based on LDPC Code

作　　者：肖骁 吴学智[1] 隗小斐 XIAO Xiao;WU Xuezhi;WEI Xiaofei(College of Electric Engineering,Naval University of Engineering,Wuhan 430033)

机构地区：[1]海军工程大学电子工程学院,武汉430033

出　　处：《舰船电子工程》2021年第8期155-158,共4页Ship Electronic Engineering

摘　　要：水声信道带宽窄、环境噪声高、传播损失大且多径效应严重,信号通过信道会产生严重的失真与畸变,误码率上升,通信性能下降。论文对限制水声信道带宽频率的主要因素进行研究分析,并建立了一种水声多径时变衰落信道。信道编码采用准循环低密度奇偶校验码(Quasi-Cyslic Low-Density Parity-Check Codes,QC-LDPC),利用对数似然比置信算法(Log-likelihood Ratios Belief Propagation,LLR-BP)进行译码,与扩频技术、高阶调制技术相结合,仿真结果表明相比于turbo码和卷积码,在水声扩频通信系统中LDPC码纠错能力更强,在低信噪比下保证系统可靠的运行。The underwater acoustic channel has narrow bandwidth,high environmental noise,large propagation loss and serious multipath effect.The signal will cause serious distortion and distortion through the channel,the bit error rate will increase,and the communication performance will decrease.In this paper,the main factors limiting the bandwidth frequency of underwater acoustic channel are studied and analyzed,and a hydroacoustic multipath time-varying fading channel is established.The channel coding uses Quasi-Cyslic Low-Density Parity-Check Codes.Using Log-likelihood Ratios Belief Propagation for decoding,combined with spread spectrum technology and high-order modulation techniques,the simulation results show that the underwater acoustic spread spectrum is compared to the turbo code.The error correction capability of the LDPC code in the communication system is stronger,and the system operates reliably at a low SNR.

关 键 词：水声通信 水声信道 QC-LDPC 扩频 

分 类 号：TN929.3[电子电信—通信与信息系统]