GPS导航定位中周跳探测和修复方法

提出了一种基于双频观测数据的单历元周跳探测和修复方法.该方法分三步实现:(1)将上一历元的模糊度代入当前历元的观测方程,消去模糊度参数;(2)利用拟准检定法检测当前历元是否有异常观测,若有,则判断出发生周跳的卫星;(3)利用LAMBDA方法计算出周跳,与前一历元的模糊度相加,即为当前历元的模糊度.该方法能准确判定出异常观测,即发生周跳的卫星.文中算例与其他方法作了比较,结果验证该方案是可行性的.

METHOD FOR DETECTING AND REPAIRING CYCLE SLIPS IN GPS NAVIGATION

A new method is proposed for detecting and repairing cycle slips in GPS navigation based on the dual frequency observations. It can be implemented through the following three steps: (1) The integer ambiguities of the current epoch are substituted by that of the previous epoch, so the ambiguity parameters are removed from the observation equations. (2) The abnormal observations are detected using the quasi accurate detection (QUAD) method and the satellite pairs of these abnormal observations are determined. Then the coefficient matrix of these satellite pairs is recovered. (3) The cycle slips of these satellite pairs are calculated using the LAMBDA method and integer ambiguities of the current epoch can be determined by adding the cycle slips into the integer ambiguities of the previous epoch. The key of this method is that the abnormal observations must accurately be detected, i.e., the satellites having cycle slips must correctly be judged. Finally, compared with other methods the feasibility of the method is verified.