基于删余极化码的卫星导航信道编码方法

Satellite Navigation Channel Coding Method based on Puncturing Polar Codes

针对当前导航信号抗干扰性能差的问题,提出一种基于译码可靠性的动态删余极化码的卫星导航信道编码方法。通过分析GPS-L1C信号帧结构,发现其子帧存在CRC校验,且子帧2和子帧3存在错误的不对等性。在不增加冗余的情况下,利用CA-SCL译码方法,对子帧3存在的不同页采用码率自适应的不等错误保护,随后通过仿真实验验证了该方法的性能。实验结果表明,在信号误帧率方面,相比于GPS-L1C信号采用的LDPC码,动态删余极化码可以获得1.6~2 d B的增益,且子帧2和子帧3的误帧率增益维持在0.4 d B以下。相比于LDPC码,提出的删余极化码具有更低的硬件复杂度,可为我国北斗卫星导航系统的电文编码设计提供参考。

Aiming at the problem that the anti-jamming performance of navigation signals is poor,the new method of satellite navigation channel coding based on dynamic puncturing polar codes is proposed.Analysis on GPS-L1C signal frame structure indicates that there exist CRC checks in its subframes,and also erroneous unequals of between subframe2and subframe3.Without increasing redundancy and by using CA-SCL decoding method,unequal error protection of the code rate adaptive is performed in conjunction with the different pages in which the subframe3exists,and then the actual performance verification of the method is carried out.The experimental results show that the dynamic puncturing polar codes could acquire1.6～2dB gain as compared with the LDPC code used in the GPS-L1C signal at the signal frame error rate,and the frame error rate gain of subframe2and subframe3is maintained within0.4dB.Compared to the LDPC code,the proposed punctured polarization code has an even lower hardware complexity.The research results could provide certain reference for the message-coding design of Beidou satellite navigation system.