An Energy-Efficient TDMA Protocol for Clustered Wireless Sensor Networks

Wireless sensor networks have been widely used in many important areas. Medium access control (MAC) protocols have a significant effect on the function and performance of sensor networks. Though the TDMA-based MAC protocols are inherently collision free and can rule out idle listening since nodes know when to transmit, it is difficult to change the frame size and time slot assignment due to network topology or traffic load changes. In this paper, we present an energy-efficient TDMA protocol for clustered wireless sensor networks (EC-TDMA), which is an intra-cluster communication MAC protocol. EC-TDMA dynamically changes the length of TDMA frame according to the number of sensor nodes and the sensor node traffic load within a cluster, reduces the idle listening and improves channel utility, thus prolongs networks lifetime. The simulation results show that this protocl performs better than existing protocols in the average energy consumption, packet delivery ratio and average latency.