MAC Layer Performance with S teerable Multibeam Antenna Arrays

In this paper, we are concerned with the performance at the media access control (MAC) layer of the protocol stack when multibeam adaptive antenna arrays are employed at the base station site. Specifically, we analyze the performance of slotted ALOHA when the base station receiver uses multibeam antenna arrays capable of steering the beams selectively on smaller sectors. The effect of different beamwidths, number of beams, beam steering patterns, and beam service times on the achieved throughput-delay performance of slotted-ALOHA is evaluated. It is observed that under high load conditions steered beams with long beam service times offer better performance, whereas under light load conditions static coverage patterns are better.