Scheduled Channel Access Using Geographical Classification
Geographical Classification Multiple Access (GCMA) is introduced for scheduled channel access in large wireless networks. GCMA uses the geo-spatial coordinates of nodes, together with their transmission and interference ranges, to define collision-free transmission schedules using deterministic distributed algorithms. These algorithms require each node to know only the geo-spatial coordinates of its immediate neighbors to derive correct transmission schedules, even in the presence of hidden terminals. The transmission frames in GCMA consist of the minimum number of time slots needed to avoid multiple access interference, given the transmission and interference ranges of the nodes. GCMA is compared against representative examples of alternative approaches to medium access control; the results of the simulation experiments show that GCMA attains higher packet-delivery ratio and better goodput with end-to-end delay comparable to the other protocols.