星地激光通信RS-LDPC级联码抗干扰优化

Satellite-Ground Laser Communication RS-LDPC Cascaded Code Anti-Interference Optimization

摘要:

星地激光通信因大气湍流、云层遮挡及平台震动等因素可能引发随机与突发混合干扰,信道编码作为关键的纠错技术备受重视；为提升星地激光通信的信道译码性能、增强信息传输效率并降低译码复杂度,设计了将RS码与LDPC码级联的编码方案;为有效刻画混合干扰特性,采用了GE-AWGN级联模型作为信道建模基础,引入含素数模自适应交织器与层间双向反馈的RS-LDPC串行级联编码架构构建分层纠错体系,提出了基于导频辅助法的动态参数调节策略优化码率、LDPC迭代次数及交织深度配置,依托MATLAB仿真平台验证了方案性能；经仿真结果表明,与未编码相比,RS-LDPC级联编码在误码率时性能优于单一LDPC码或RS码约1.5 dB,动态参数调节在低信噪比下显著提升了纠错效果,在高信噪比下有效提高了传输吞吐量,自适应交织器高效离散了长突发错误；经实验测试该信道模型与编码方案适配星地激光通信混合干扰场景,满足了抗干扰传输技术在该领域的实际应用需求。

Abstract:

Due to factors such as atmospheric turbulence, cloud cover, and platform vibration, random and burst mixed interference may occur in satellite-to-ground laser communication. Channel coding, as a key error correction technology, has received significant attention. To enhance the channel decoding performance of satellite-to-ground laser communication, improve information transmission efficiency, and reduce decoding complexity, a coding scheme that cascades RS codes and LDPC codes is designed. To effectively characterize the mixed interference characteristics, a GE-AWGN cascaded model is adopted as the basis for channel modeling. A RS-LDPC serial concatenated coding architecture with a prime modulus adaptive interleaver and inter-layer bidirectional feedback is introduced to construct a hierarchical error correction system. A dynamic parameter adjustment strategy based on pilot-assisted method is proposed to optimize the code rate, LDPC iteration times, and interleaving depth configuration. The performance of th