###### Abstract
utilized PDOP, the number of visible satellites, and orbital altitude as the objective functions. The multi-objective particle swarm optimization (MOPSO) algorithm was employed to optimize the design of three different configuration constellations: a single polar constellation, a single tilt constellation, and a hybrid configuration constellation. The findings indicate that the hybrid constellation exhibits superior coverage performance [8]. [PERSON] et al. conducted an analysis of the fundamental performance of the developing BeiDou Global Navigation Satellite System (BDS-3); proposed methodologies for enhancing positioning, navigation, and timing (PNT) services; and highlighted the BDS-3 as a core provider of PNT services to users in deep-space and deep-sea environments [9; 10]. Additionally, they discussed how LEO constellations not only enhance the accuracy, continuity, and availability of PNT services but also improve their reliability, integrity, and security [11; 12]. [PERSON] et al. employed NSGA-III and GA to design LEO global independent navigation constellations as enhanced constellations. They introduced constellations with varying heights and numbers of near-polar constellations along with hybrid configuration constellations [13]. [PERSON] et al. utilized the NSGA-III optimization algorithm to design LEO augmentation constellations comprising 177 and 186 satellites, demonstrating significant enhancements in GDOP, convergence time, and positioning accuracy performance for the hybrid constellation [14]. [PERSON] et al. employed a genetic algorithm to design hybrid configuration constellations with varying total numbers of satellites, achieving uniform global coverage at \(7^{\circ}\), \(15^{\circ}\), and \(20^{\circ}\) elevation angles for LEO navigation enhancement [15]. Furthermore, NSGA-III was applied to optimize the design of two LEO navigation enhancement constellations: Polar/Walker (S1) and Walker/Walker (S2), each with different inclinations. The findings indicate that the S2 constellation excels in enhancing global service performance of BDS-3 [16]. In comparison to LEO satellites, MEO navigation satellites incur high costs for both production and deployment. They are also vulnerable to service disruptions in complex space environments due to factors such as single-particle flipping, satellite decommissioning, signal shutdown or interference, and life expiration. [PERSON] et al. noted that in geometrically well-formed constellations, even in the absence of critical satellites, there may exist critical pairs as well as critical groups of three or four satellites that render the constellations unreliable. GPS adheres to the most stringent reliability standards, with a worst-case scenario involving up to five critical satellites rendering the constellation unusable [17]. [PERSON] et al. analyzed the operational performance of navigation constellations in the Asia-Pacific region under various of single- and double-satellite failure modes and proposed an optimal design model for reconfiguring navigation constellations based on genetic algorithms [18]. It is essential to examine the relationship between constellation performance and constellation configuration following an MEO satellite failure. A malfunction in MEO navigation constellations could lead to decreased service performance impacting user experience significantly. Therefore, during the phased deployment, the LEO navigation constellation will complement and enhance the underperforming MEO constellation to ensure a seamless transition of constellation performance. Constellation deployment is an intricate process that cannot be hastily accomplished. Hence, maximizing sub-constellation functionalities at each stage is crucial for incremental performance enhancement while ensuring robust scalability throughout construction phases, thereby striking a balance between costs and risks [19].