Collaborative Design of Integrated Trajectory Planning and TT&C Relay Communication for Lunar Far-side Sampling and Return Mission

Marked by the successful return of the re-entry capsule carrying 1 935. 3 grams of lunar far-side samples to Earth,the Chang’e-6 mission—the first human-executed lunar far-side sampling and return endeavor—has successfully completed all flight phases as predetermined. Serving as a backup to the prior Chang’e-5 mission on the lunar near side, and with major technical baselines unchanged,the far-side sampling and return mission introduces heightened complexity in inter-system flight planning and tracking,telemetry,and command(TT&C)coordination. For example,the lunar orbit is altered from prograde to retrograde, leading to prolonged flight durations and additional constraints； far-side communication relies on a relay satellite deployed in advance；and limited TT&C resources must be strategically allocated across diverse missions and systems. Focusing on collaborative mission design among multiple systems,the work on joint trajectory planning and TT&C relay analysis is systematically reviewed and summarized,offering valuable technical and methodological insights for future deep space exploration missions.