Utilizing beamforming for random access - a cross-layer paradigm

Adaptive beamforming has been shown to substantially improve the performance of a slotted Aloha packet radio system. In this paper we present a slotted Aloha based random access protocol designed to be employed in conjunction with adaptive beamforming, for use in a sectorized wireless system. The focus is on a cross-layer design approach, in which information about the status of packet transmissions is utilized to dynamically adapt antenna beams among the sectors in a cell. This scheme is especially robust against the network inefficiencies due to uneven and time-varying traffic load densities within the sectors of a cell. Simulation results demonstrate the substantial enhancement in throughput and delay performance due to the proposed scheme.