Instantaneous Real-Time Cycle-Slip Correction for Quality Control of GPS Carrier-Phase Measurements

This paper proposes a new cycle-slip correction method that enables instantaneous correction (i.e., using only the current epoch's GPS carrier-phase measurements) at the data quality control stage. The method was originally developed for real-time applications that require consistent high-precision positioning results with the carrier-phase measurements at a 10 Hz data rate. The approach includes (1) two parameters for generating and filtering cycle-slip candidates, and (2) a validation procedure that authenticates correct cycle-slip candidates. Compared with conventional approaches using carrier phases and pseudoranges, the approach does not require a smoothing or filtering process to reduce observation noise. Therefore, it is possible to implement the approach in real-time applications without undue complexity. Simulation tests were conducted to confirm the performance of the approach under worst-case scenarios. Test results for a variety of situations, including static and kinematic modes, short-baseline and long-baseline situations, and low and high data rates, are presented.