基于异常值探测的GPS双频特殊周跳探测

GPS Dual-Frequency Special Cycle Slip Detection Based on Outlier Detection

GPS周跳是影响测量成果精度的重要因素之一,其多值性以及如何判断各自频率上周跳,特别是特殊周跳尤为重要.本文针对双频(9,7)型和(77,60)型特殊周跳,利用异常值检验方法,考虑其成对出现特点,通过约束双频上周跳ΔN1、ΔN2的范围来计算满足Δφ=ΔN1-(λ2/λ1)Δ2的整数解的方式探测周跳.通过采样率为1 s、5 s及10 s的GPS数据验证,无论是连续还是非连续特殊周跳,采用本文方法不但解决了多值问题,而且能准确探测出各频率上的周跳,计算准确,成功率100%.

GPS cycle slip is one of the important factors affecting the accuracy of measurement results. The multi value of the GPS cycle slips and how to judge the cycle slips of different frequency, especially the special cycle slips, are particularly important. Aiming at the dual-frequency(9,7) and(77,60) special cycle slips, this paper used the outlier test method to detect cycle slips by constraining the range of double frequency cycle slips ΔN1,ΔN2 to calculate the satisfied Δφ=ΔN1-(λ2/λ1)Δ2 integer solution, considering their pairing characteristics. Through the GPS data with sampling rate of 1 s, 5 s and 10 s, whether continuous or no-continuous special cycle slips, the method proposed in this paper can not only solve the multi value problem, but also accurately detect the cycle slips on each frequency. The calculation is accurate and the success rate is 100%.