NavIC Signals Multipath Analysis, Estimation and Mitigation for High-Accuracy Positioning

Our objective is to assess the PVT accuracy of a stationary receiver using NavIC and explore ways to improve it using single and dual-frequency observables. We also propose a method to extend Breivik et al. approach of estimating multipath error using signal to noise ratio. Position accuracy using smoothed single-frequency pseudoranges is within 5 m, 3D residual-sum-of-squares (RSS), for the 22-hour duration with PDOP varying between 3-3.2. Further improvement in precision is shown by compensating multipath using sidereal repeatability but this process introduces a bias in the estimates. Velocity estimation accuracy using carrier phase measurements has 3D RSS mean and 1-sigma of 5.2 mm/s and 3.18 cm/s, respectively, which is better than the Doppler-derived estimates mean of 82.9 mm/s and 4.51 cm/s (1-sigma). We show better accuracy for both the position and velocity estimates as compared to the receiver's estimates.