Tdoa Based Tracking Measurement for Geo Satellites Orbit Determination: Evaluation for the Satellite Operators

Abstract

The satellite's orbit determination has recently evolved with new tracking data and data processing methods and algorithms developments. The satellite operators need the current and future motion of the satellites for operational purposes and use various methods to measure the tracking data. This study investigates the time difference of arrival (TDOA) based ground data measurement and processing of these tracking data to obtain orbital parameters and the communication satellite operators' use of the method. First, a conceptual ground station network was established to collect TDOA based tracking data. Then these data were processed to determine the orbits using a sequential process (SP) filter method. The results were analyzed by comparing radial, in-track, and cross-track positions and velocities for three satellites at different orbital locations. The mean root mean square error (RMSE) differences of radial, in-track, and cross-track (RIC) position values of three satellites are about 19 m, 5 m, and 1 m, respectively. Similarly, the mean RMSE differences of RIC velocity values are about 0.8 cm/s, 0.15 cm/s, 0.05 cm/s respectively. These values are below the success criteria that are satellite typical flight dynamics requirements. The estimated communication satellites orbit with TDOA based observation data are fully consistent with truth orbit parameters. The satellite operators can utilize the proposed TDOA measurement method with its benefits to estimate satellite orbit.