Speed and direction adaptive call admission control for high altitude platform station (HAPS) UMTS

One of the unique characteristics of high altitude platform station (HAPS) Universal Mobile Telecommunications System (UMTS) is that the transmit antenna beams of all base stations originate from the same phased array antenna onboard the platform. Using this unique characteristic, we propose and analyze a new speed and direction adaptive call admission control (CAC) scheme for HAPS UMTS. Through simulation, we evaluate the performance of the proposed scheme in a military operating environment where users tend to move collectively in groups. Results show the proposed CAC scheme outperforms the conventional CAC scheme in terms of grade of service (GoS)