一种ΔDOR算法的初步实现  

Preliminary implementation of a ΔDOR algorithm

作　　者：邓涛 马茂莉[1] 刘庆会[1] 郑鑫[1] 李培佳[1] DENG Tao;MA MaoLi;LIU QingHui;ZHENG Xin;LI PeiJia(Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 200030,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院上海天文台,上海200030 [2]中国科学院大学,北京100049

出　　处：《中国科学：物理学、力学、天文学》2022年第2期107-116,共10页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家自然科学基金(编号:11773060,11973074,11703070,11803069);国家重点基础研究发展计划(编号:2018YFA0404702)资助项目。

摘　　要：ΔDOR(双差分单向测距)技术是一种广泛应用于深空探测的测角技术.中国VLBI(甚长基线干涉测量)网目前使用互相关方法实现ΔDOR技术,然而在信号的信噪比很低时,使用基于互相关方法的相关处理机进行时延测量会有弱信号处理能力不足的局限性.随着更遥远距离的深空探测的推进,对弱信号求时延将成为必然的任务需求.本文将高性能三阶锁相环作为测量信号的频率和相位的基本模块,并由此推导了一种弱信号处理能力较强的基于本地相关的ΔDOR算法.该算法避免了传统本地相关方法中本地模型信号与含噪信号进行互相关运算时引起的算法性能损失问题,同时算法更为简洁.对天问一号数据求残余群时延间接验证了本文提出的算法的可行性,为进一步发展高性能ΔDOR技术提供了一种方案.Delta-differential one-way ranging(ΔDOR) technique is an angle measurement method widely used in deep space exploration. Currently, cross-correlation methods are used to realize the ΔDOR technology in China’s very long baseline interferometry networks. However, when a signal has a very low signal-to-noise ratio, the cross-correlation methods have a limited processing ability owing to a weak signal. With advancements in distant deep space exploration, calculating the time delay of weak signals has become necessary. In this paper, a high-performance third-order phase-locked loop is used as the basic module to measure the frequency and phase of a signal, and then a ΔDOR algorithm based on local correlation with high weak-signal-processing ability is derived. This algorithm avoids the performance loss caused by the cross-correlation between the local reference and received signals in a traditional local correlation method and is concise.The feasibility of the proposed method is indirectly verified by calculating the residual group delay of the observation data from Tianwen-1, thereby providing a scheme for the further development of the high-performance ΔDOR technique.

关 键 词：甚长基线干涉测量 双差分单向测距 群时延 

分 类 号：P228.6[天文地球—大地测量学与测量工程]