In this paper, we designed the time differenced carrier-phase (TDCP) based global positioning system (GPS) and inertial navigation system (INS) integrated system properly considering the noise correlation. The TDCP based navigation can determine the precise position using good quality carrier phase measurements without difficulty in resolving integer ambiguity. Since the TDCP contains current and previous information that violate the format of the usual Kalman filter, the delayed state filter which considers correlated process and noises is utilized to improve the accuracy and reliability of GPS/INS system using TDCP. To verify the proposed algorithm, dynamic simulation and experiment were conducted. In the simulation and experiment, it is confirmed that it shows up to 70% and 60% performance improvements compared to conventional algorithm.

Keywords: GPS/INS, time-differenced carrier phase, noise correlation