BDS三频观测值多路径误差的差异性分析

摘要

BDS分布在3个不同高度的轨道上且同时播发3种频点的信号数据,导致其观测值多路径误差可能在星座间、频点间存在差异.基于此,利用我国iGMAS跟踪网络和国际MGEX跟踪网络的17个GNSS多模观测站数据,从高度角、信号频点、接收机类型、跟踪站分布以及卫星星座等5个方面进行BDS多路径误差的差异性分析,同时与同源观测站上的GPS观测值多路径误差进行对比.结果表明,B3频点的多路径误差最小;3种星座间,GEO卫星的多路径误差最小;BDS的GEO卫星和IGSO卫星的多路径误差在地域上无明显的差异;BDS的B3频点上的多路径误差优于GPS 3个频点上的对应结果,BDS的B1和B2频点与GPS的L1和L2频点上多路径误差的精度相当.%BDS is composed of three different heights of orbital satellites and broadcasts three-frequency signals,which may lead multipath to present new features.These characteristics cause the multipath error of BDS observations to possibly differ between constellation and the frequency.Based on this,by using the 17 GNSS multimode observatory data from the MGEX and iGMAS,the diversity of BDS multipath error is analyzed from five aspects of elevation angle,signal frequency,receiver type,tracking station distribution and satellite constellation.At the same time,the multipath errors of GPS observations are compared with that of homologous observation stations.The conclusions are as follows:the multipath error of the B3 is lowest;the multipath error of the GEO satellite is less than that of IGSO's and MEO's in the three constellations;there is no significant difference in the multipath errors between the GEO and the IGSO;compared to the multipath error of GPS,the result of B3 is slightly better than the results of GPS three frequency points,the results of B1 and B2 are equivalent to that of the L1 and L2 in accuracy.