Performance evaluation of mobile radio slotted ALOHA with fixed multibeam antennas

In this paper, we report our investigation into the effect of using fixed multibeam antennas on the performance of the slotted ALOHA protocol with capture in a mobile communications environment with Rayleigh and Log-normal fading. We consider the configuration where multiple receivers are present at each base station and calculate the capture probability, its asymptotic value as the number of colliding packets tends to infinity, and throughput when multiple receivers are used. The results demonstrate that by using fixed multibeam antennas, we can achieve higher performance in terms of capture probability and throughput when compared to a conventional antenna system using the slotted ALOHA protocol.