北斗亚欧全视时间比对试验

Experiment of BeiDou Asia-Euro All-in-View Time Transfer

基于卫星导航双频时间传递型接收机的伪码观测量,利用国际全球卫星导航系统服务组织(International Global Navigation Satellite System(GNSS)Service,IGS)提供的高精度卫星轨道和钟差产品,实现了北斗全视法时间比对.以IGS提供的时间尺度为两个待比对站的公共参考时间,首先使用双频组合法消除电离层对伪距观测的影响,然后将对流层和地球自转效应带来的时延利用理论模型在伪码观测量中进行扣除,分别获得两个比对站时间与公共参考时间之差后,将2者再做差,便得到了北斗全视时间比对结果.以中国科学院国家授时中心(NTSC)、德国物理技术研究院(PTB)和西班牙海军天文台(ROA)所保持的国家标准时间作为比对对象,开展了长基线北斗全视时间比对试验,获得北斗全视时间传递结果,最后利用阿伦方差和时间方差两项关键性能指标以及卫星双向时间比对对其进行性能评估.结果表明:北斗全视时间比对的天稳为10-14量级,可以满足国际时间比对需求.

Based on the pseudo-code observations of dual-frequency time-transfer receivers for satellite navigation,high-precision satellite orbit and clock difference products provided by the International Global Navigation Satellite System(GNSS)Service(IGS)are used to realize the time comparison of the BeiDou All-in-View method.This method takes the time scale provided by IGS as the common reference time of two stations to be compared.Firstly,the effect of the ionosphere on pseudo-range observations is eliminated by using the dual-frequency combination method.Then,the delay caused by the troposphere and the earth rotation effect is deducted by using the theoretical model in pseudo-code observations.After the difference between the two stations and the common reference time is obtained respectively,the results of All-in-View time comparison of BeiDou are given.Taking the national standard time maintained by the National Time Service Center(NTSC)of the Chinese Academy of Sciences,Physikalisch-Technische Bundesanstalt(PTB),and Real Instituto y Observatorio de la Armada(ROA)as comparison objects,a long baseline BeiDou All-in-View time comparison test is carried out.Two key performance indicators,Allan deviation and time deviation,and two-way satellite time and frequency transfer are used to evaluate the performance of the BeiDou All-in-View method.The results show that the stability of BeiDou All-in-View time comparison can reach the order of magnitude of1×10-14 d-1,which can meet the international time comparison requirements.