惯导辅助的无电离层与宽巷组合周跳探测与修复方法

An INS-Aided Cycle Slip Detection and Repair Method Based on IF and WL Combinations

由于卫星信号被遮挡、低信噪比或接收机运动等原因,载波相位观测值较正常值会发生周跳。为解决这一问题,基于精密单点定位与惯导组合系统,提出了一种有效的惯导辅助周跳探测与修复方法。该方法基于无电离层(ionospheric free,IF)组合与宽巷(wide lane,WL)组合,利用惯导短时高精度信息代替伪距消除站星几何距离,结合历元间差、星间差等建立惯导辅助的IF组合模型和惯导辅助的WL组合模型。惯导辅助的IF组合模型不受电离层延迟影响,但无法探测特殊比例周跳,惯导辅助的WL组合模型波长较长,却无法探测双频等周周跳,两者的综合使用实现了优势互补。实验结果表明,该方法不仅能有效探测出各种大、小、双频等周和特殊比例周跳,而且在一定卫星信号中断时间内能实现周跳瞬时校正。

Cycle slips often occur in carrier phase observations due to the problem of the obstruction, low signal-to-noise ratio, or high receiver dynamics. An effective INS(inertial navigation system)-aided cycle slip detection and repair method is presented, which is based on PPP/INS integrated system. It utilizes high-precision INS information instead of a pseudorange to remove the satellite-receiver geometric range in the wide-lane and ionospheric-free phase combinations, cooperates with satellite and epoch differential processing, and creates INS-aided wide-lane model and INS-aided ionospheric-free model. The INS-aided ionospheric-free model is unaffected by the dramatic changes in the ionosphere but cannot detect the special pairs of cycle slips. The INS-aided wide-lane model has a long wavelength. However, it is insensitive to the equal cycle slips on dual frequencies. So their combination can achieve mutual complementary advantages. The results show that this method can effectively detect and repair various types of cycle slips. Moreover, when it comes to the cycle slip after a GPS interruption, the method can realize the instantaneous correction.