PMPS: Predictive Multi-Path Scheduling for Handover-Free LEO Communications

摘要

Low Earth Orbit (LEO) mega-constellations promise seamless global service, yet satellites racing overhead force handovers every few minutes, disrupting service for billions of users worldwide. Current systems maintain exclusive single-path connections despite modern phased arrays’ ability to track multiple satellites simultaneously, accepting these disruptions as unavoidable and merely minimizing instead of eliminating them. We propose PMPS (Predictive Multi-Path Scheduling), designed to achieve handover-free satellite communications through proactive continuous multi-path service. PMPS eliminates the reactive single-path service interruption through three integrated designs: (i) introducing multiplicative composite weights combining visibility time, signal quality, and capacity factors orchestrates continuous traffic redistribution, ensuring gradual and seamless packet migration across all active satellites. (ii) proving optimal multi-satellite packet scheduling is NP-complete, then developing polynomial-time approximation algorithms achieves provably near-optimal performance within real-time constraints. (iii) eliminating obstruction-induced packet loss through anticipatory selective redundancy protects vulnerable connections. As satellites approach the horizon becoming vulnerable to obstruction, their declining weights have shifted most traffic to higher satellites. Redundantly transmitting only the minimal remaining packets through stable satellites ensures zero loss if obstruction occurs. Evaluation on Starlink and OneWeb constellations demonstrates PMPS enables handover-free LEO communications with minimal redundancy overhead.