Prioritized multi-channel MAC protocol in ad hoc networks using a TDMA/CSMA approach

摘要

Multi-channel ad hoc networks are promising technology to alleviate the spectrum scarcity in dense networks. The main challenge for channel access in distributed multi-channel ad hoc networks is channel synchronization and competition with neither common control channel nor dedicated control transceiver. In this paper, a Tight Synchronized MAC protocol with distributed synchronization and competition process without any dedicated control channel is proposed. The protocol uses a simple handshaking mechanism to create a channel table for each node, which contains its neighbors and channels' status. By this, any node knows the priority of its channels and also the priority of neighbors' channels. By assigning priorities, a sender node starts synchronization. If sender and receiver nodes have a common channel, the proposed method finds it directly or indirectly using the common neighbor mechanism. The other feature of the proposed scheme is using a fair preemptive data transmission phase, which reduces the number of switchings along data transmission. The fair preemptive mechanism is achieved by an analytical solution to estimate the number of competing nodes and thus, estimates the number of assigned data slots. Simulation results show the performance improvements in terms of synchronization delay and packet delivery ratio over HMMAC and MSRMMAC protocols.