달 남극점에서의 PNT를 위한 항법위성 궤도군 설계

• Published in: Journal of Positioning, Navigation, and Timing Vol. 14; no. 2; pp. 131 - 138
• Main Authors: 강민재, 정호준, 박재욱, 송준원, 기창돈, Minjae Kang, Hojoon Jeong, Jaeuk Park, Junwon Song, Changdon Kee
• Format: Journal Article
• Language: Korean
• Published: 사단법인 항법시스템학회 01.06.2025
• Subjects: 기타공학
• ISSN: 2288-8187; 2289-0866
• DOI: 10.11003/JPNT.2025.14.2.131

The Lunar Navigation Satellite System (LNSS) is designed to provide precise positioning information to users on the lunar surface, similar to the Global Navigation Satellite System (GNSS) on Earth. However, various perturbative forces can cause the orbits of lunar navigation satellites to change over time, degrading navigation performance. Given the high cost of lunar orbit insertion, maintaining stable orbits is critically important. This paper presents the design of satellite orbits that offer long-term, reliable navigation services at the lunar south pole. To maintain orbital stability, we analytically derived the conditions for lunar frozen orbits, considering the dominant perturbative influence of Earth's three-body gravity using the Lagrange planetary equations. Additionally, we analyzed the stability changes of Frozen orbits when additional perturbative forces due to the Moon's oblateness are considered, specifically incorporating the J2 term. Among the candidate stable frozen orbits that account for both Earth's three-body gravity and lunar perturbations, we selected the optimal orbits based on their superior navigation performance, which was evaluated using the Dilution of Precision (DOP) metric. The long-term navigation performance at the lunar south pole was then verified through orbital propagation simulations.