一种改进的北斗导航卫星伪距偏差修正策略  

An improved code bias correction strategy for BDS

作　　者：饶鹏文 王潜心[1] RAO Pengwen;WANG Qianxin(School of Environment Science and Spatial Informatics,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China)

机构地区：[1]中国矿业大学环境与测绘学院,江苏徐州221116

出　　处：《测绘科学》2020年第7期1-10,共10页Science of Surveying and Mapping

基　　金：江苏省研究生科研与实践创新计划项目(SJCX19_0906);中国矿业大学科研与实践创新计划项目(SJCX19_0906)。

摘　　要：针对北斗第二代导航卫星系统的伪距观测值中存在与卫星相关的系统性伪距偏差的问题,该文提出采用加权分段曲线建模方法建立北斗IGSO/MEO卫星观测数据三频改正模型。试验表明,改正后IGSO与MEO卫星的伪距偏差明显削弱。针对GEO卫星伪距偏差问题,提出了一种基于Tikhonov正则化的建模方法;修正后的GEO卫星MP序列的RMS在B1、B2、B3频率上分别下降了35.9%、29.6%、35.8%。为了验证策略的可行性,设计了3套单频PPP定位方案,结果表明:通过改正IGSO/MEO卫星伪距偏差,N、E方向定位精度平均提高了20.2%和13.4%,U方向定位精度平均提高了62.8%;同时改正GEO/IGSO/MEO卫星的伪距偏差时,U方向的定位精度将进一步提高至70%左右。因此本研究提出的BDS-2卫星伪距观测值的修正模型,能有效减弱这些伪距偏差的影响。There are systematic biases related to satellites on the pseudo-range observations of the second-generation Beidou navigation satellite system(BDS-2).In order to correct the code biases,the three-frequency correction model of Beidou IGSO/MEO satellite observation data is established by using the weighted piecewise curve modeling method;The experimental results show that the code biases of the IGSO and MEO satellite are clearly mitigated.For the code biases of GEO satellites,this paper proposes a modeling based on regularization.After the correction,the STD of GEO multipath time series decreased by 34%、28%、36%respectively in B1、B2、B3 frequency.In order to verify the feasibility of this strategy,we designed three sets of single-frequency PPP schemes.The results indicate that the positioning accuracies of the north and east directions are improved by 20.2%and 13.4%on average,and the positioning accuracy of the up direction is improved by 62.8%on average by correcting the code biases of IGSO/MEO satellite.By applying the GEO code bias,the accuracy of the up direction can be further improved to about 70%.Therefore,the improved correction model proposed in this study can effectively reduce the influence of the code biases.

关 键 词：北斗卫星导航系统 多路径组合 伪距偏差 TIKHONOV正则化 单频精密单点定位 

分 类 号：P237[天文地球—摄影测量与遥感]