Dilemma of using high datarate in IEEE 802.11B based multihop ad hoc networks

Due to the fact that high datarate has shorter transmission range, the benefit of using high datarate may be degraded for IEEE 802.11 based multihop ad hoc networks. In this paper, we evaluate the performance of multihop ad hoc networks at multirates, in terms of the number of hops between source and destination, throughput, and end-to-end delay. Through simulations carried out in chain topology, we find that there is almost no benefit by applying the highest datarate 11 Mbps in 802.11b when the chain length is 6 hops or more. With node mobility in mesh topology, the benefit of using high datarate diminishes at even fewer hops. In order to better understand the reasons for this performance degradation at high datarate, analyses on end-to-end throughput in multihop networks and k-connectivity are carried out later in the paper.