Improved Design of Beach Ball Constellation for Constant Revisit Time in LEO Reconnaissance

Recent conflicts, such as the Ukrainian war, highlight the need for advanced surveillance methods. Small satellite constellations present cost-effective solutions for surveillance missions. In light of the increasing significance of cross-border intelligence surveillance, this paper addresses the design of beach ball (BB) constellations optimized for reconnaissance missions in low Earth orbit (LEO). Unlike previous empirical methods, we propose a mathematical approach to design a BB constellation, ensuring stable and constant monitoring of a specific Area of Interest. We considered dominant \({J}_{2}\) $J_2$ perturbation in LEO, allowing satellites to pass over designated observation points with consistent revisit times. The paper provides a comprehensive overview of BB constellation design, including background on sun-synchronous orbits and ground repeat tracks. Additionally, we introduce a collision inspection method and strategies for collision avoidance, enhancing operational safety.