Multipath analysis of code measurements for BeiDou geostationary satellites
Multipath analysis of code measurements for BeiDou geostationary satellites
复制标题
北斗静止卫星代码测量的多路径分析
DOI：
10.1007/s10291-014-0374-8
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发表时间：
2015-01-01
期刊：
影响因子：
4.9
通讯作者：
Guo, Jing
中科院分区：
文献类型：
--
作者：
Wang, Guangxing;de Jong, Kees;Guo, Jing
多径延迟对代码范围可观测值的影响不可忽视，是限制 GNSS 定位精度的误差源之一。由于相对静止的几何形状，来自地球静止轨道（GEO）卫星的信号的多径效应更难以通过仅仅增加观测周期或对多个历元进行平均来减轻。为研究北斗GEO卫星的编码特性和多径效应，采用反映编码多径的线性观测组合，利用傅里叶变换、相关和小波变换对长周期BDS多径时间序列进行分析。 GEO 多路径序列的幅度从 <1.0 m 到 2.0 m 左右变化，主要每日重复分量的周期在 86,130 到 86,280 s 之间。提取低频分量，连续两天的低频分量之间的互相关系数大部分大于0.7。当从第二天的多径时间序列中减去第一天的低频分量时，发现代码标准差下降了25%以上。通过前日低频多径观测值的校正，可以提高北斗一二频或一三频无电离层线性组合的纯码单点定位精度。澳大利亚珀斯两个站的北、东和向上部分的精度分别提高了 0.2、0.5 和 0.4 m，以及 0.3、0 和 0.5 m。
Having non-negligible impact on the code range observables, multipath delay is one of the error sources that limit GNSS positioning accuracy. Due to the relatively stationary geometry, multipath effects for signals from geostationary earth orbit (GEO) satellites are even more difficult to mitigate by merely increasing the observing periods or averaging over multiple epochs. To investigate the characteristics of code, multipath effects for the BeiDou Navigation Satellite System (BDS) GEO satellites, a linear combination of observations reflecting code multipath was employed and BDS multipath time series over long periods were analyzed with the Fourier transform, correlation and wavelet transform. The amplitudes of GEO multipath series vary from <1.0 m to around 2.0 m, and the periods of the dominant daily repeating components fall between 86,130 and 86,280 s. The low-frequency components were extracted, and most cross-correlation coefficients between the low-frequency components of two consecutive days are larger than 0.7. When the low-frequency components of the first day are subtracted from the multipath time series of the second day, a decrease of more than 25 % is found in terms of the code standard deviations. By correcting the observables with low-frequency multipath of the previous day, the precisions of code-only single-point positioning using ionosphere-free linear combination of BDS first and second or first and third frequencies can be improved. Precision improvements in north, east and up components for two stations in Perth, Australia were shown to be 0.2, 0.5 and 0.4 m, and 0.3, 0 and 0.5 m, respectively.