Seamless Inter-Constellation Sharing via Handover-Aware Space-Ground Association

Constructing a low-Earth orbit (LEO) satellite network is both capital-intensive and time-consuming. To accelerate deployment and reduce costs, inter-constellation sharing, where multiple satellite network operators (SNOs) share their satellite constellations to build LEO networks collaboratively, has emerged as a promising direction. However, the inherent dynamics of LEO satellites inevitably lead to frequent handovers between terrestrial users and core networks operated by different SNOs, posing significant challenges to network continuity and stability.This paper presents Satitch, a new framework that mitigates the adverse effects of inter-SNO handovers and facilitates seamless LEO constellation collaboration. The key idea behind Satitch is to decouple access satellites from individual SNOs’ core networks, enabling flexible association between shared satellite access points and multiple core networks. This design choice allows terrestrial users to remain connected to their original SNOs as much as possible. Concretely, Satitch incorporates a flexible, dynamic scheduling algorithm for space-ground connections that aims to minimize inter-SNO handovers experienced by terrestrial users. Further, Satitch adopts a proactive handover optimization to alleviate the impacts of inevitable interruptions. Our evaluation based on real-world constellation data demonstrates that Satitch can reduce up to 99.87% flow-level disruption time as compared to existing approaches and ensure smooth real-time video playback.