Design And Implementation Of Data Link Layer Protocol For AD HOC Network Based On Android System

Ad Hoc network is a multi-hop temporary autonomous network which combines mobile communication and computer network and does not have the fixed infrastructure. Ad Hoc network which does not need the fixed infrastructure, has the features of dynamic network, no center and autonomy, so it has broad application prospects in the military communication, emergency services and disaster rescue.First, this paper has presented an overview of Ad Hoc network and Android platform, and a review of MAC layer protocols which has detail analysis of key technologies and problems in designing MAC protocol.Second, it has discussed the main problems in IEEE802.11DCF and proposed improvement program. It’s proposed an algorithm which has adaptive RTS threshold adjustment by transfer time and a back-off algorithm by integration. So the new algorithms have improved the utilization of the channel and reduced problems between throughput and fairness. It has presented the modification of802.11DCF by a network simulation software. The simulation showed that the improved algorithm has better performance and has good potential in applications.Finally, it has implemented the improved802.11DCF protocol based on Android system.