GPS全视法时间传递回顾与展望

目前,时间传递技术正处于GPS伪码技术到GNSS多种技术组合的过渡时期,介绍了高精度时间传递技术在近年来的发展情况:首先回顾了GPS伪码共视(CV)与全视法(AV)时间传递,并证明全视法比共视法更具优越性。CCTF 2006通过,从MJD 53979,即2006九月(Circular T225)开始,使用AV法进行TAI比对。CV法需要满足共视条件,这限制了载波相位(CP)方法的应用,载波相位观测量比码观测量的观测精度可以高出两个数量级。由于CP观测数据优良,CCTF 2006推荐也可以引用CP观测数据进行时间传递。PPP方法是一种充分研究的时间传递方法,它充分地利用了载波相位信息,可以认为是伪码AV法的自然延伸。最后,给出我们的最新研究成果,即将GPS PPP和TW时间链路结合的方法,该方法结合两种时间传递链路的优点并消除了它们的缺点。

Review and Perspective of GPS All in View Time Transfer

Face an epoch passing from GPS code only to NGSS multi-technique time transfer.Introduces the recent developments in high accurate time transfer:First review the GPS code Common View(CV)and All in View(AV)time transfers and proves that the AV is more advantageous than CV.The CCTF 2006 authorized to generate TAI with AV and this is done since MJD 53979,Sept.2006(Circular T 225);CV requires the simultaneous satellite CV condition which restricts the use of the CP observation which is two orders more precise than the code.The CCTF 2006,based on the encouraging results,recommended also the use of the CP in TAI time transfer.One of the well studied methods is PPP that,as the natural follower of the code AV,fully use the high precise CP information.Finally we introduces our latest study result,the combination of the GPS PPP and TW time links,which gathers the advantages of the both linking techniques and reduces the disadvantages.