Comparison of telemetry, tracking, and command approaches for very low Earth orbit satellites
摘要
Due to the serious impact of atmospheric drag, the very low Earth orbit satellite must maintain its orbital altitude autonomously, which poses a new huge challenge to the ground control system. To provide a reference for the overall design of satellite engineering, this paper conducted a comparative study on the telemetry, tracking, and command approaches for very low Earth orbit satellites, including ground stations, tracking and data relay satellites, geostationary Earth orbit, and low Earth orbit communication satellites. Through theoretical analysis and computer simulations, the orbit prediction bias caused by autonomous orbit maintenance was obtained, and the access duration, tracking performance, and coverage of various telemetry, tracking, and command schemes were determined.
The results show that the instantaneous antenna beamwidth coverage of the ground station likely fails to cover the orbit prediction bias, making it impossible to reliably track the very low Earth orbit satellite. The tracking and data relay satellite has better instantaneous antenna beamwidth coverage, and the geostationary Earth orbit and low Earth orbit communication satellites do not require the user’s position: both are capable of tracking very low Earth orbit satellites. In terms of access duration and satellite coverage, ground stations, communication satellites, and tracking and data relay satellites are in ascending order. In the typical simulation scenarios of this paper, tracking and data relay satellites can provide more than 90% coverage, while low Earth orbit communication constellations can provide 46% to 90% coverage with great potential for future development.