Autonomous Control Method and Verification of Dual Antenna Tracking Relay Satellite on the Far Side of the Moon

In response to the communication needs of data transmission via relay satellites on the moon’s far side, and under various engineering constraints such as the rotation frequency of directional antennas, the temperature of the rotation mechanisms, and the continuous relay tracking by dual antennas, an autonomous control method for dual directional antennas has been proposed, which can be executed onboard. This method utilizes a simplified two-body orbit extrapolation model onboard. Based on grouped orbit parameters injected from the ground, it autonomously calculates the position of the relay satellite, eliminating the need for a complex three-body gravitational perturbation model for lunar satellites, thereby making onboard calculations more efficient. Additionally, by incorporating parameters such as the lander’s position, attitude, and antenna installation matrix, it autonomously calculates the target angle for the directional antennas and generates control commands for the dual-axis mechanism to position the antennas correctly. Ground-Based and in-orbit verification results have proven the method to be reasonable and feasible. Furthermore, it has been verified in-orbit during China’s first automatic sample return mission from the far side of the moon, with the pointing accuracy meeting operational requirements. This provides a technological foundation for future deep space exploration missions involving the tracking of relay satellites by directional antennas.