Distributed Node Scheduling Algorithms for Multiple Group Communications in Wireless Multi-hop Networks

We study the scheduling problem in performing multiple multicast communications in wireless multi-hop networks, it is necessary to ensure that each multicast group can complete one transmission from the source to all the destination nodes without conflict in every frame. The present study proposes two distributed token-based STDMA node scheduling algorithms which not only satisfy this requirement, but also minimize the frame length. In the first algorithm, the multicast groups are scheduled on a group-by-group basis, whereas in the second algorithm, multiple groups are scheduled in each scheduling operation. The first algorithm has the advantages of computational simplicity and a straightforward implementation, while the second algorithm increases the percentage of reused time slots and reduces the number of token forwarding events. The simulation results show that both algorithms achieve a shorter frame length than existing methods.