A synchronized MAC protocol considering packet generation intervals in wireless sensor networks

Wireless sensor networks (WSNs) consist of a lot of sensor nodes with limited battery, memory, and processing capability. Therefore, in WSNs, effective MAC protocol is required to maximize battery life of sensor nodes, to reduce transmission delay, and to minimize communication errors. Routing enhanced MAC (RMAC) uses the path information on network layer so that multi-hop transmission within a cycle is possible. RMAC can reduce transmission delay and energy consumption compared to Sensor-MAC (S-MAC). However RMAC with a fixed duty cycle does not dynamically adapt to network traffic characteristics. In this paper, we propose Dynamic-RMAC (D-RMAC) to improve the performance of RMAC. D-RMAC adaptively varies duty cycle as packet generation intervals in nodes. In addition, D-RMAC increases the number of transmission hops in a cycle by one. The simulation results show that D-RMAC represents better performance than S-MAC and RMAC.