Study On Synchronous Channel Reservation Access Protocol In Mobile Ad Hoc Networks

Mobile Ad Hoc Networks are self-organized and have no center, and they do not need fixed network infrastructures. Since this network can quickly build network platforms for military and civilian applications, it is the key technology in the future wireless communication networks. Because of the status of nodes are equal in an Ad Hoc network, the Media Access Control(MAC) protocols which based on a fixed network or a cellular network are unable to meet the special needs. So channel access protocols suitable for Ad Hoc networks need to be designed. "No conflict" multiple access protocols are the development direction of Mobile Ad Hoc network.A technique based on time division multiple access protocol called C hannel Reservation- Time Division Multiple Access(CR-TDMA), which designed for Ad Hoc networks, is studied in this paper. First, the frame format, packet format and partition principle of time slot are described. Second, this protocol uses different synchronization broadcast channel allocation mechanism in the dense and sparse network scenarios to complete the process of nodes building or entering a network. This mechanism not only improves the radio channel utilization but also shortens the average access delay of packets. Finally, according to the MAN ET’s different in scale, node speed and service models, CR-TDMA protocol researches synchronization broadcast channel reservation mechanism. Such mechanism can help the nodes complete reservation and release synchronization channels and further improves the network performance.In this paper, a Mobile Ad Hoc network model is established with OPNET simulation software, and node rate, network load and network size parameters are set for different network simulation. The simulation results show that the design of synchronization channel reservation access protocol based on Time Division Multiple Access(TDMA) can adapt to the fast dynamic changes of topology in the network, effectively support the requirement of average access delay of burst traffic, and improve the network throughput.