A traffic adaptive sleep MAC protocol for wireless sensor network

This paper presents a new medium access control (MAC) protocol for wireless sensor networks (WSN). This new MAC is supposed to improve the energy efficiency of WSN. A lot of proposed MAC protocols are based on periodic sleep approach. A typical method is to let sensor nodes follow a schedule to listen or sleep. Usually, that schedule is initialized at the beginning of the MAC process. Few papers proposed methods to dynamically decide the sleep schedule during the MAC process. But those approaches are not aimed at adapting the traffic state. A measuring mechanism is proposed to analyze traffic state in one cluster of WSN. According to traffic state, sensor nodes change their sleep schedules. Sensor nodes can sleep a lot when network is idle, and work as normal when network is busy. This new scheme is evaluated by a simulation compared with Bit-Map-Assisted MAC protocol. Two protocols are compared in terms of energy consumption and transmission delay. Simulation result shows the proposed MAC mechanism can use energy more efficiently.