基于GLONASS频间偏差的GNSS时差监测方法研究
Research on GNSS time offset monitoring based on GLONASS IFBs
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摘要: 为实现各导航系统的兼容与互操作,需要对各导航系统间的时间偏差进行实时监测.目前,全球卫星导航系统(GNSS)时差监测的主要方法是利用空间信号法进行GNSS时差监测.由于GLONASS系统频分多址的信号体制,导致GLONASS接收机频间偏差(IFB)的存在,GLONASS IFB会影响到GNSSGLONASS的系统时差监测.为消除这一影响,本文提出了基于GLONASS IFB估计的GNSS时差监测方法,由仿真结果可知,利用该方法可以将GPSGLONASS时差监测精度平均提高90%以上.Abstract: To enhance the compatibility and interoperability among GNSSs, it is necessary to monitor system time offset among GNSSs. At present, the main method of GNSS time offset monitoring is Signal-in-Space Reception method. Because of the FDMA technique, GLONASS satellites have different signal frequencies. It leads to IFBs for both pseudorange and carrier phase observations. The GLONASS IFBs will influence the GNSS-GLONASS system time offset monitoring. To reduce the impact of GLONASS IFBs, this paper proposes a method of GNSS time offset monitoring with GLONASS IFBs estimated. The simulation result indicates the accuracy of GPS-GLONASS time offset can be improved by more than 90% on average.