High throughput slotted ALOHA packet radio networks with adaptive arrays

The authors consider the use of a multiple-beam adaptive array (MBAA) in a packet radio system. In an MBAA, a given set of antenna elements is used to form several antenna patterns simultaneously. When it is used in a packet radio system, an MBAA can successfully receive two or more overlapping packets at the same time. Each beam captures a different packet by automatically pointing its pattern toward one packet while nulling other, contending packets. It is shown how an MBAA can be integrated into a single-hop slotted ALOHA packet radio system, and the resulting throughput is analyzed for both finite- and infinite-user populations