Study on Handover Techniques for Satellite-to-Ground Links in High and Low Interference Regimes

Abstract

The launch of private non-geostationary satellite orbit (NGSO) satellite constellations in recent years such as SpaceX's Starlink and Amazon's Kuiper has put satellite communications in focus as a potential provider of high-throughput broadband services. It is expected that satellite networks will be integrated into future 6G networks, and fortify global connectivity in the upcoming years. One major challenge with these NGSO networks, is the mobility-management. Due to the inherent high speed mobility of the satellites, the coverage area from a particular satellite to the ground is constantly moving, so frequent handovers are needed to sustain satellite-to-ground links. In this paper, we implement and evaluate the impact of three satellite-to-ground-link handover (HO) strategies, namely Closest Satellite, Max-Visibility and CINR - Threshold on the satellite-to-ground link performance in terms of spectrum efficiency and HO rate under high and low interference regimes. We consider three prominent private LEO mega-constellations namely SpaceX Gen2, Kuiper and OneWebLEO; and one MEO constellation namely Mangata, all operating in the Ka-band. Through extensive simulations we show that the CINR-Threshold strategy gives the best trade-off between throughput and HO rate, irrespective of the constellation design, level of interference and location.