Cycle slip detection and estimation for ground-based high-precision local positioning system

Abstract

Global Navigation Satellite Systems (GNSSs) have become an almost indispensable part of our infrastructure and modern life, but in a specific environment have its limitations, or cannot be applied. Pseudollites are ground-based transmitters that can provide similar navigation measurements as GNSSs. GH-LPS developed by NUDTis a new pseudolite system allows centimeter-accuracy single-point positioning for a mobile or static device. Carrier phase observations are commonly used in high-precision positioning applications, due to their millimeter precisions. Any cycle slip, if remained undetected, would deteriorate the high accuracy positioning. Hence, it is crucial to handle the cycle slips in the carrier phase measurements for GH-LPS. Carrier phase-based RAIM (CRAIM) algorithm is proposed to detect and estimate small cycle slips. In order to evaluate the performance, a kinematic test was conducted. The experiment demonstrated that the CRAIM method can be used to solve the problem of small (e.g. 1 cycle) cycle slips and GH-LPS can provide single point positioning with centimeter-level accuracy and sub-centimeter level precision.