An energy-efficient TDMA scheduling for data collection in wireless sensor networks

In a low traffic wireless sensor network, the energy spent on nodes´ state switching is non-negligible because of limited energy consumption on data transmission. In this paper, we proposes a centralized scheduling algorithm to minimize the nodes´ state switching times by using TDMA and multichannel techniques. Our algorithm uses a receiver-based slot assignment strategy to assign consecutive slots to nodes so that the nodes can finish their data collection continuously only need to wake-up once. In addition, a greedy channel assignment approach is used to minimize the number of channels, and we prove the number of channels used by our algorithm is less than log₂^N+1, where N denotes the number of nodes in the data collection tree. The simulation results show our algorithm can reduce the energy consumption by minimizing the state switching times and so increasing the life-time of nodes. In addition, our algorithm also can achieve the optimum data collection time.