An Efficient Area-Division Based Handover Scheme in LEO Satellite Networks

Low-Earth orbit (LEO) satellite communications play a vital role in global and emergency communications and the movement of LEO satellites around the Earth necessitates frequent handovers for terrestrial users. Efficient handovers are complicated due to the limited coverage and rapid movement of LEO satellites, as well as the high mobility of user equipment (UE), leading to significant handover overhead. To address these challenges, this paper introduces an efficient area-division based handover scheme, in which, the Earth's surface is divided into areas. To reduce the impact of the UE's speed on the handover decision and reduce the handover overhead, handover decisions are made for areas instead of individual UEs based on the satellite trajectories and area characteristics when UEs move within the same area. The graph-based approach is used to compute the handover sequence, which takes multiple handover factors into account to ensure handover performance. We analyse the effects of area size and UE's speed on the overhead and handover failure rate. The experimental results verify that the proposed handover scheme can reduce the handover overhead and improve the handover success rate and data transmission efficiency.