一种“北斗”卫星导航系统三频周跳探测与修复方法

针对传统伪距-相位组合中伪距噪声过大的问题引入了多普勒观测值进行辅助，同时再联合无几何相位组合构成一种新的周跳探测与修复方法。在信号方面，选择B2a代替B2I,与B1I、B3I组成了“北斗”卫星导航系统(Beidou Navigation Satellite System, BDS)中定位性能更好的“北斗”三频观测组合。在选频方面，选用无几何相位系数-1,1,0]、多普勒辅助伪距-相位系数1,0,-1],1,3,-4]组合进行周跳的探测。在修复方面，使用搜索法进行周跳的修复，并根据1-范数原则确保修复值的准确性。在1 s的采样率、电离层延迟稳定情况下，所提方法不仅能探测与修复出所有加入的1周在内的周跳，而且相比传统伪距-相位方法在小周跳探测方面性能更佳。

A method for detecting and repairing triple-frequency cycle slips of Beidou navigation satellite system

Doppler observations are introduced to resolve the problem of the excessive values of pseudorange noise in the traditional pseudorange-phase combination.Besides,the proposed cycle-slip detection and repair method is combined with the geometry-free phase combination.In terms of signal selection,B2a that is selected instead of B2I,together with B1I and B3I,forms a three-frequency observation combination with better performance in the Beidou Navigation Satellite System(BDS).In terms of frequency selection,the combination of geometry-free phase coefficients\-1,1,0\]and Doppler-assisted pseudorange-phase coefficients\1,0,-1\],\1,3,-4\]is used to detect cycle slips.For repairing cycle slips,the search method is used and the 1-norm principle is suggested to ensure the accuracy of repaired values.When the sampling interval is 1 s and the ionospheric delay is stable,the proposed scheme can not only detect and repair all cycle slips occurred in one cycle,but also get better performance compared with the traditional pseudorange-phase scheme in the detection of small cycle slips.