Terminal Position Tracking in LEO Satellite Communication Systems Exploiting Doppler and Multiantenna Measurements.

A connected vehicular terminal supported by Low Earth Orbit (LEO) Satellite Communication (SatCom) can exploit the communication signal for navigation during Global Positioning System (GPS) outage. We propose an algorithmic framework for tracking position and velocity of the terminal exploiting Doppler and direction of arrival (DoA) measurements from the LEO SatCom signals, together with readings from the Inertial Measurement Unit (IMU) of the vehicle. The main idea is to use these measurements as the input to an Extended Kalman filter (EKF) designed to keep tracking the position of the terminal during a blockage event of the GPS signal. Simulation results show that the proposed algorithm reduces the localization error by more than 50 meters when compared to the results of IMU-only based tracking.