Low-Earth-Orbit Mega-Constellation Low-Redundancy Design: Rapid Performance Analysis and Adaptive Configuration Layering

Megaconstellations, which offer convenient communication and navigation services, are at the forefront of satellite application advancements. However, traditional constellations with a single uniform configuration fail to meet the various demands in different regions, thus leading to low utilization. In addition, satellite safety becomes a key consideration that megaconstellations cannot ignore. To address the aforementioned problems, this study proposes an adaptive method for designing layered megaconstellations under the assumptions of circular orbits, uniform distribution in each plane, and a pregiven altitude. Two novel methods are developed for evaluating the coverage performance and satellite safety. First, the longitude-coverage-ratio model is proposed based on the street of coverage theory, enhancing the constellation design for latitude-specific coverage needs. Next, a rapid method is derived for calculating the minimum angular distance between planes. Then, the study investigates the models to be used in subconstellation design techniques for assembling multilayer hybrid megaconstellations. Several hybrid megaconstellations are designed, demonstrating the applicability of the methodology for both nonuniform and global uniform coverage requirements. The results show that this method offers reduced redundancy and a lower number of satellites compared to a single Walker. The examples also suggest that low-Earth-orbit hybrid constellations can achieve global uniform coverage when reaching sufficient coverage folds.