基于三差的GPS周跳探测与修复

GPS Cycle Slip Detection and Correction on the Base of Trip Difference

应用GPS载波相位进行相对定位能够达到厘米级精度,其前提是载波相位观测值中没有周跳并求得了正确的初始整周模糊度,因此,周跳探测和修复一直是GPS定位尤为关心的问题之一。本文提出了先用三差再差对周跳进行初步探测与修复,然后用三差迭代解进一步探测与修复数值较小的周跳的方法,该方法不仅简单,而且有效。理论分析的计算结果表明:对于短基线,当接收机钟误差达到±10-5秒时,应用三差再差基本上可以准确地探测与修复周跳,即使接收机钟达到±10-4秒,也能探测到10周左右的周跳,在此基础上再用三差迭代解能够准确地探测与修复所有剩余的周跳。

The DGPS （differential GPS） accuracy has already reached centimeter. Such high accuracy is based on the observation data that without cycle slip. Detection and correction cycle slip have been given much attention in the last 1-2 decades and there are many different developed methods such as multi-difference, linercombinations, fitting with multinomial and so on. This paper presents a new method named diference of triple difference, also named as the fourth difference. It can detect any cycle slip in the very short baseline or detect the cycle slip about 5 cycles. Additionally, the small cycle can be continuously detected by iterative algorithm with triple difference.