Throughput Analysis of an Aloha-Based MAC Policy for Ad Hoc Networks

Re-use of existing widely explored Medium Access Control (MAC) schemes, like the well-known Aloha scheme, is not applicable in ad hoc networks where the transmissions of the users can be normally sensed by only a fraction of the users present in the network. Therefore, estimations of the network traffic load are not possible anymore. Here, an adaptive probabilistic policy for medium access control in ad hoc networks, inspired by the Aloha paradigm, is proposed and analyzed. Simulation results show that this policy is capable of achieving higher system throughput when compared to other policies that have been proposed for ad hoc networks. It is also shown that mobility severely impacts the system throughput and therefore, an alternative approach is proposed that reduces the effects of mobility in the expense of the maximum achievable system throughput.