短帧长 CCPM 信号优化设计及简化译码

摘要

Considering the demand of burst communications, optimization and simplified decoding for coded GMSK system in short frame was focused on to give an optimum proposal of C2PM system. Simplified demodulator, optimized generation polynomial of the convolution code and matched interleavers were discussed. Simulation results show that for coded GMSK system under AWGN, the performance is better than individual convolution code. Especially when BER is 1×10-5, it performs better than Turbo code and LDPC code with the same frame length, and there is no error floor occur-ring. Finally, complexity analysis shows that the coded GMSK system has lower implementation complexity in compari-son with the commonly used convolution code, Turbo code and LDPC code.%　　针对突发通信和卫星测控通信中对于短帧长、高性能和低复杂度的需求，提出一种短帧长C2PM（coded continuous phase modulation）系统的优化设计方案，包括编码GMSK系统的优化设计及简化译码。对于编码GMSK系统，采用简化解调器、优化卷积码生成多项式和匹配交织器的方式，可实现系统参数优化。加性高斯白噪声（AWGN）信道下的仿真结果表明，系统性能优于常用卷积码性能，特别是在10-5误比特率时，略优于同帧长的Turbo码和LDPC码性能，且无误码平底出现。对编码GMSK系统复杂度的分析结果表明，该系统实现复杂度低于常用卷积码、同帧长Turbo码和LDPC码。