Dynamic TDMA Slot Assignment Protocol for ulti op oc etworks

The design of an efficient medium access control (MAC) for ad hoc networks is challenging. In this paper, we propose a dynamic TDMA slot assignment protocol (DTSAP) for ad hoc networks. According to the topology density of the network and the bandwidth requirement, our proposed protocol controls the excessive increase of unassigned slots by changing the frame length and the transmission schedule dynamically. It allows a transmitter to choose one or more slots from the set of unassigned slots in its neighborhood, coordinate the announcement and confirmation of the assignment with the neighboring nodes up to two hops away, detect and resolve conflicting assignments that result from the mobility of the nodes. Moreover, our proposed protocol provides the collision- free packet transmission among nodes with different frame length. The important sections of the proposed protocol including frame format and slot assignment are presented and analyzed. The simulation results show that our proposed protocol improves the average throughput dramatically as compared with the conventional TDMA protocols and 802.11.