GNSS空间信号法时差监测方法与结果分析

比较了3种基于GNSS空间信号进行时差监测的方法,其中,单站精密单点定位(PPP)时差监测法依赖于卫星轨道和钟差的精度,高精度PPP一般采用事后处理的方法;网解时差监测法受卫星轨道误差的影响较小,且不受卫星钟差误差的影响,因此能够用于高精度时差实时监测。为分析不同方法时差监测的差异,在距离不同的时间实验室之间进行了时差试验,试验中将外接相同原子钟的两个测站的时差用于评定时差监测的精度,而相距2000 km的测站用于验证高精度实时时差监测的精度。结果表明:1实时网解与事后PPP时差监测的精度相当,达到了0.16 ns;2采用PPP方法,是否固定站坐标时差结果差异的RMS为0.04 ns;3采用实时网解的方法,对于相隔数千千米的测站实时时差监测,其与PPP后处理结果的差异约为0.14 ns。

Research and Results Analysis of Methods of GNSS Spatial Signal Time Monitoring

Methods using GNSS signal in space to monitor time offset among timing stations are dicussed.Three methods namely the traditional PPP,PPP with fixed station coordinates and the real-time network solutions are compared.To validate and assess the performance of SIS time offset monitoring,data of 5 GNSS stations with different configurations are analyzed.Results show that:(1)Precision of real time network solutions is 0.16 ns,which is at the same level of post-processed PPP.(2)Station coordinates estimation has impact on the determination of station clocks,which is about 0.04 ns.(3) Precision of time transfer for stations depart 2000 km could reach 0.14 ns in the real-time network solution.