单一多径环境下GPS载波跟踪误差建模与分析

为研究伪码多径误差对载波多径误差的影响，文中分析了采用非相干早码减晚码功率型伪码跟踪环时Costas载波跟踪环的载波多径误差，并建立了单一多径下的载波多径误差模型. 所建立的模型表明伪码多径误差对载波多径误差的影响可以表示为多径参数和相关间距对载波多径误差的影响. 理论和仿真分析结果表明，单一多径下载波平均跟踪误差为0，且当相关间距小于一个码片时，载波跟踪误差最大值小于π/2；多径参数对载波跟踪误差的影响较大，而相关间距对载波跟踪误差的影响较小. 

Modeling and Analysis of GPS Carrier Tracking Error in the Presence of Single Multipath

In order to study the influence of multipath code tracking error on multipath carrier tracking error, the multipath carrier error of Costas carrier tracking loop was analyzed when the non-coherent early minus late power mode code tracking loop was used, and the multipath error model of Costas loop was established in the presence of single multipath. The established model indicates that the influence of multipath code tracking error on multipath carrier tracking error can be expressed as the influence of multipath parameters and correlation space on carrier tracking error. The theory analysis and simulation results show that the mean carrier tracking error is zero in the presence of single multipath, and the maximal carrier tracking error is less than π/2 when the correlation space is smaller than one chip. It also indicates that the multipath parameters have more influence on the carrier tracking error than the correlation space.