Reduced Kalman Filter for RDSS/INS Integration Based on Time Differenced Carrier Phase

Radio determination satellite service can provide both communication and positioning service through a group of geo-stationary satellites. The active-mode positioning of RDSS can lead to big time lag and user capacity limitation, and cannot provide continuously position, velocity and attitude outputs. To overcome these shortcomings a passive-mode RDSS/INS integration method is proposed. The velocity errors arc estimated and corrected by an extended Kalman filter using time-differenced carrier phase as measurements. The linearized observation equation is deduced and a reduced filter using Kalman-Schmidt algorithm is designed. Ship tests are performed to validate the principles and to evaluate the performance.