With the ever-increasing lunar missions, a growing interest develops in designing data relay satellite constellations for cislunar communications, which is challenged by the constrained visibility and huge distance between the earth and moon in pursuit of establishing real-time communication links. In this work, therefore, we propose an age and coverage optimal relay satellite constellation for cislunar communication by considering the self-rotation of the earth as well as the orbital motion of the moon, which consists of hybrid Earth-Moon Libration 1/2 (EML1/L2) points Halo orbits, ordinary lunar orbits, and Geostationary Earth Orbit (GEO) satellites. In particular, by minimizing both the number of satellites and the average per-device Age of Information (AoI) while maximizing the coverage ratio of specific lunar surface regions, a multi-objective optimization problem is formulated and solved by using a well-designed Nondominated Sorting Genetic Algorithm-II (NSGA-II). The simulation results demonstrate that our proposed hybrid constellation significantly outperforms traditional Walker Star and Delta constellations in terms of both AoI and the coverage of communication.

翻译：随着月球任务的日益增多，设计用于地月通信的数据中继卫星星座引起了越来越多的关注，这一设计面临着地球与月球之间受限的可见性和巨大距离的挑战，旨在建立实时通信链路。因此，在本工作中，我们通过考虑地球的自转以及月球的轨道运动，提出了一种年龄与覆盖最优的地月通信中继卫星星座，该星座由混合的地月平动点1/2（EML1/L2）晕轨道、普通月球轨道以及地球静止轨道（GEO）卫星组成。具体而言，通过最小化卫星数量与平均每设备信息年龄（AoI），同时最大化特定月球表面区域的覆盖比例，我们构建了一个多目标优化问题，并采用精心设计的非支配排序遗传算法-II（NSGA-II）进行求解。仿真结果表明，我们提出的混合星座在AoI和通信覆盖方面均显著优于传统的Walker Star和Delta星座。