Abstract: An analytic formula of saturation throughput is presented for multi-hop Ad Hoc networks, which takes packet collision and channel conditions into account. Based on the formula, a rate adaptation mechanism is proposed. The scheme can adjust the rate of sending packets exactly, and choose the optimal size of packets to best match channel conditions for maximizing saturation throughput. Simulation results show that the scheme outperforms OAR and 802.11 DCF with 10% and 260% improvement on the saturation throughput and channel-resiliency capability.

Key words: wireless Ad Hoc network, MAC protocol, channel state, rate adaptation