压缩域直扩测控通信信号伪码跟踪方法研究

Study on Pseudo-noise Code Tracking Method for Compressive Domain Direct Sequence Tracking Telemetry and Command Communication Signals

压缩感知理论已经在测控(TT&C)通信相关领域有初步应用尝试,能够有效降低采样率和数据率,但同时其重构算法复杂度偏高、计算资源消耗过大,这与系统的实时性要求之间存在矛盾。论文基于直扩测控(DS TT&C)通信信号稀疏性,对传统伪码跟踪环进行改进,提出一种基于随机解调压缩采样的压缩域伪码跟踪环。该环路不再需要进行信号重构处理,能够直接从直扩测控通信信号的压缩采样值中提取伪码(PN)延时相位信息。该文首先深入分析所提出环路模型及其鉴别特性,其次通过研究交叉噪声特性,对跟踪精度进行理论分析。分析和仿真结果表明,所提出环路能够在压缩域实现伪码延时相位跟踪。该环路可以应用在基于压缩感知的直扩、混扩信号处理等相关领域,具有一定工程应用价值。

Compressive sensing has a preliminary application to the field of Tracking, Telemetry, and Command （TT^C） and communication, which can effectively decrease sampling and data rate, but there is a contradiction between the real-time requirement and the computationally expensive recovery algorithm. In this paper, based on the sparsity of Direct Sequence （DS） TT＆C and communication signals, a compressive domain Pseudo-Noise（PN） code tracking loop based on random demodulation compressive sampler is proposed. The loop can directly extract the code phase from compressive signal samples, which does not need to recover original signal. Firstly, the loop model and its identification characteristics are analyzed. Secondly, through research on cross noise, tracking accuracy is analyzed. Theoretical analysis and simulation results show that the proposed loop can track PN code phase in compressive domain. The loop may have an important application value to the field of DS Spread Spectrum （SS） and DS/Frequency Hopping （FH） Hybrid SS （HSS） signal processing based on compressive sensing.