Efficient TDMA scheduling algorithms for sensor networks containing multiple rings

In this paper a special ring topology is investigated for sensor networks, where the whole network is decomposed into subnetworks forming rings, and these subnetworks are connected to each other through a main ring. Each of these subnetworks may have different requirements concerning message delivery times. In this paper algorithms are proposed, which generate such networks from the connectivity graph, and create TDMA scheduling for the generated network. The proposed algorithms can handle the requirements of various delivery times, and can provide parallel operation of nodes, where possible, to decrease the overall length of the schedule. The theoretical results are supported by measurement examples.