π-旋转LDPC码在浅海水声信道中的性能研究  

Performance Analysis of the π-rotation LDPC Codes in Shallow Underwater Acoustic Channels

作　　者：金晓婷[1] 许肖梅[1] 陈友淦[1] 

机构地区：[1]厦门大学海洋与地球学院,水声通信与海洋信息技术教育部重点实验室,福建厦门361102

出　　处：《厦门大学学报（自然科学版）》2016年第1期103-107,共5页Journal of Xiamen University：Natural Science

基　　金：国家自然科学基金(41376040,41476026);中央高校基本科研业务费专项资金(20720140506)

摘　　要：浅海水声信道具有快速时变、严重多径干扰和多普勒频移的特征,为保证水声数据传输的可靠性,需采用纠错能力强、编译码复杂度低的信道编码技术.低密度奇偶校验(low density parity check,LDPC)码凭借其逼近香农限的优势被选为水声信道编码方案,但其构造复杂度有待优化.本文介绍了一种码率为1/2的π-旋转LDPC码的构造方法,研究其在水声信道上的性能,并结合实际水声信道特点选择编译码参数.仿真结果表明:π-旋转LDPC码在浅海水声通信系统中可行有效,与准循环(quasi cydic,QC)LDPC码性能接近,优于随机LDPC码,在码长1 024bit、译码迭代次数为50时基本能满足水声通信误码率10-4的要求.π-旋转LDPC码对数据的存储空间需求相对较小、易于硬件电路实现,在水声通信系统中有广泛的实用前景.The shallow underwater acoustic （UWA） channel has the characteristics of rapid temporal variation, severe multipath disturbance and Doppler frequency shift.The channel coding technique with strong error correction capability and low complexity in coding and decoding has been proposed to enhance the reliability of the shallow water acoustic （SWA） communication system. This paper proposes the x-rotation low density parity check （LDPC） codes as an error-correcting coding scheme and introduces the construction and encoding method of the x-rotation LDPC codes, combining with the actual characteristics of underwater acoustic channel to select the coding parameters.Through simulations,we show that the designed π-rotation LDPC codes are effectively and tremendously improve the performance of underwater acoustic communication system, which are better than the random LDPC codes and quite similar to quasi cydic （QC-）LDPC codes. They can meet the basic requirement of UWA communication with the BER of 10-4 at a code length of 1 024 bit and an iteration number of 50.With less memory space,the x-rotation LDPC codes have good application prospects in underwater acoustic communication.

关 键 词：π-旋转LDPC码 水声通信 信道编码 

分 类 号：TN929.3[电子电信—通信与信息系统]