High-Precision Positioning Based on Carrier Phase and Unscented Kalman Filter in the Presence of Base Station Calibration Errors

In scenarios where high-precision localization is required, even tiny calibration errors of the base station (BS) can directly and significantly impact the positioning accuracy of the device. Inspired by the excellent precision of carrier phase positioning, this paper proposes a high-precision positioning algorithm based on carrier phase and unscented Kalman filter (UKF) to address BS calibration errors. The state vector of the positioning system is initialized with the initial coordinates of the terminal, which is estimated via Chan's algorithm. The coordinates of the BSs and the terminal are then iteratively refined by combining the double-differential carrier phase and time difference of arrival (TDoA) measurements of multiple moments. Numerical simulations demonstrate that the proposed algorithm achieves centimeter-level positioning accuracy even in the presence of significant BS calibration errors, which effectively overcomes the impact of BS calibration errors on positioning performance.