S-TDMA: A New MAC Protocol for Wireless Sensor Networks

Due to the fact that sensor nodes are untethered and unattended, energy management is a critical issue in communication mechanism of a wireless sensor network. In this paper, we address this problem and propose a novel solution based on media access control technique. Our protocol STDMA (for Sensor-Time Division Multiple Access) exploits the inherent features of TDMA to avoid the main sources of energy wastage. It assigns sensors with consecutive time slots to reduce the frequency of state transitions. S-TDMA is carefully designed to overcome the high latency of traditional TDMA protocols. It also conserves energy when a node may not be transmitting or receiving packets. Simulation results show that the S-TDMA protocol functions well.