深空测控再生伪码测距技术研究

针对深空测控任务中低信噪比情况下的航天器高精度测距问题,对再生伪码测距技术进行论述。介绍再生伪码测距技术原理,再生伪码测距通过再生方式消除信号上行链路噪声,提高了信噪比,但需要复杂的相关器;分析再生伪码测距采用的陶思沃斯码结构,详细论述再生伪码测距信号的地面上行、星上再生、地面下行处理过程,重点介绍各处理过程中的指标条件,并对再生伪码测距进行误差分析;重点对比分析再生伪码测距与传统透明转发测距,指出前者适合于深空低信噪比条件下的高精度测距,后者适用于近地高信噪比条件下的测距。

Regenerative PN Ranging Technology for Deep Space Applications

Regenerative PN(Pseudo-Noise) ranging technology is introduced to obtain high precision ranging information at low SNR(Signal-to-Noise Ratio) in deep space TT&C missions.Noise of the uplink chain is eliminated in a regenerative approach and the SNR is improved.However,a complex correlator is required.Structure of Tausworthe code used by the regenerative PN code is analyzed.Ground station uplink processing process,on-board processing progress and ground station downlink processing progress are described in detail with a highlight on the indexes of these processes.The error of regenerative PN ranging is also discussed.Comparison of regenerative PN ranging with transparent PN ranging shows that regenerative PN ranging is fit for deep space high precision measurement with low SNR while transparent PN ranging is fit for ground proximity general measurement with high SNR.