An Improved Access Scheme Based on Multiple-Hop Priority and Cross-Layer Design in 802.11e

In ad hoc networks, the end-to-end delay of packets becomes long when other middle nodes transmit these packets and the multi-hops will affect the quality-of-service (QoS) of voice and video. This paper analyzes influence of multi-hops in ad hoc network by a simulative experiment, which put forward an improved access algorithm, called as more hop first-EDCF (MHF-EDCF). The mechanisms are based on 802.11e EDCF and multi-hop characteristics of ad hoc networks with cross-layer method. MHF-EDCF offers a higher priority to multi-hops packets for voice and video. The results of simulation show that MHF-EDCF can reduce the end-to-end delay of multimedia traffic significantly and throughput of network is increased.