Handover Management of Aerial Users in Integrated HAPS-Ground Wireless Networks

An emerging trend in the prospective sixth-generation (6G) of wireless networks is to enhance terrestrial communication platforms by offering connectivity from the sky. Providing reliable sky coverage is, therefore, expected to have fundamental importance in enabling the connectivity of aerial equipment such as cargo drones and aerial vehicles. As a potential aerial network component with large coverage and enhanced capacity features, a high altitude platform station (HAPS) is an indispensable enabler to address the requirements of aerial users as opposed to the limited coverage that conventional terrestrial networks provide. To this end, this work aims at developing and studying an efficient mobility management solution for aerial users in HAPS-Ground integrated networks, where the aerial user can connect to the terrestrial base station, or to the HAPS that provides a better alternative communication link. The paper then proposes ways of handover skipping based on predefined system criteria, so as to minimize the impact of 3D mobility on the user experience. The performance of the proposed solution is studied by means of Monte Carlo simulation using different performance metrics including the coverage probability, handover rate, and network average throughput.