跳频抗干扰通信系统中LDPC码的编码优化设计

为进一步提升低密度奇偶校验(low-density parity-check, LDPC)编码跳频通信系统抗干扰能力, 提出一种对抗部分频带干扰样式的LDPC编码构造方法。首先针对不同干扰因子参数优化了LDPC码字在干扰环境下的度分布序列, 然后通过基于渐进边增长和近似环外信息算法构造基矩阵, 最后采用改进部分分割移位系数矩阵扩展得到校验矩阵, 并结合不等差错保护特性应用到信息位的干扰保护上。该构造方法兼顾优化的度分布和准循环结构。仿真结果表明, 所构造的码字性能良好, 相同条件下, 抗干扰性能优于现行主流类型码字的抗干扰性能。

Optimal design of LDPC codes in frequency hopping anti-jamming communication system

To improve the anti-jamming ability of low-density parity-check (LDPC) coding frequency hopping (FH) communication system, a construction method of LDPC coding against the partial band noise jamming patterns is proposed. Firstly, the degree distribution sequence of the LDPC codes in the interference environment is optimized for different interference factor parameters. Then, the progress edge growth and the approximate cycle extrinsic message algorithm are combined to construct the basis matrix. Finally, the improved partial partition shift coefficient matrix is used to expand to obtain the check matrix, combining the unequal error protection feature applied to the interference protection of information bits. This construction method takes into account both the optimized degree distribution and quasi-cyclic structure. The simulation results show that the constructed code has good performance. Under the same conditions, the anti-interference performance is better than that of the current mainstream codewords.