地空数据链信道功率和带宽利用率低,需要高效信道编码和调制技术解决这一问题。对以往编码恒包络系统进行改进,提出一种适合地空数据链信道特性的多进制LDPC—CPM串行级联系统。该编码CPM系统在级联时删减了交织环节,无须符号和比特间转换,一定程度上降低了系统复杂度。仿真结果表明,新系统具有较高的功率效率和频谱效率,可以有效减小算法资源开销,获得较低的误码率,提高地空衰落信道下系统传输的可靠性。
The features of air-ground data link are low power efficiency and spectral efficiency. A solution to solving the problem is a combine of high-efficiency coding and modulation. Due to the improvement of coded constant envelope system, this paper proposed the NLDPC-CPM system, which was suitable for the channel of the air-ground data link. This coded CPM system expunged the interlaced part, the conversion between bits and symbols, and reduced the system complexity. The results of simulation show that the NLDPC-CPM system has higher power efficiency and spectral efficiency, and effectively reduces difficulty of algorithm implementation and resource occupation. It gains lower bit error rate, and enhances the reliability of the information transmission in the air-ground fading channel.