一种应用于实时语音传输的LDPC码的设计

Design of LDPC Code for Real-Time Voice Transmission

文中设计了一种适于对声码器的输出码流进行前向纠错编码的低密度奇偶校验码(LDPC码)。该低密度奇偶校验码具有半规则化的结构,编码简单,存储量少,调整码率方便,易于硬件实现。文中同时对汉明码、卷积码、Turbo码、低密度奇偶校验码分别在AWGN、Rayleigh信道下的传输性能进行了仿真比较。仿真结果表明,长度适合的LDPC码误码性能远超过汉明码、卷积码,综合性能与Turbo码接近。

In this paper, a new encoding structure of LDPC codes used in the output bitstream of vocoder is proposed. Those codes offer many advantages, such as simple encoding structure, less memory requirement, easy circuit implementation, easy adjustment of code rate and code length, The performances of Hamming codes,convolutional codes, Turbo codes and LDPC codes in AWGN and Rayleigh channel are simulated and compared respectively.Simulation results indicate that these LDPC codes perform as well as Turbo codes, and outperform the Hamming codes and convolutional codes,