基于非相干解调的大动态Multi-h CPM遥测信号同步与检测方法

Synchronization and Detection of Highly Dynamic Multi-h CPM Telemetry Signals via Non-coherent Demodulation

摘要:

针对未来航天测控系统中新一代Multi-h CPM体制遥测信号的接收需求，提出一种适应大多普勒动态的信号同步与解调方法。采取基于符号差分处理的非相干解调技术，通过频率跟踪环路实现大多普勒动态信号的载波频率同步；通过基于序列检测的早迟门定时环路实现符号定时同步；采用BCJR算法实现最大似然序列检测，完成数据解调。仿真结果表明，在多普勒范围±1MHz，多普勒变化率200kHz/s，信息速率偏差1×10-5的超高动态条件下，载波频率同步环路和符号定时同步环路能够快速、稳定锁定，误码率满足要求，证明该方法具备工程应用价值。

Abstract:

Aiming at the reception requirements of Multi-h CPM telemetry signals in future TT&C systems, propose a method for signal synchronization and demodulation suitable for large Doppler dynamic.In terms of signal demodulation, a non-coherent demodulation technique based on symbol differential processing is employed. Carrier frequency synchronization for highly dynamic signals with large Doppler shifts is achieved through a frequency tracking loop, while symbol timing synchronization is realized using an early-late gate timing loop based on sequence detection. The BCJR algorithm is utilized for maximum likelihood sequence detection to complete data demodulation. Simulation results show that under ultra-high dynamic conditions—with a Doppler range of ±1 MHz, a Doppler rate of change of 200 kHz/s, and an information rate deviation of 1×10-5,the carrier frequency synchronization loop and symbol timing synchronization loop can achieve fast and stable locking. The bit error rate meets the requirements, prove that this method has engineering application value.