Energy-aware Adaptive Low Power Listening for Sensor Networks

Energy efficiency is a central issue for all wireless sensor network applications. Idle listening on the wireless channel constitutes a large portion of overall energy consumption in sensor networks. The need to reduce idle listening energy consumption has led recently to the design of BMAC [1], a MAC protocol for sensor networks which provides 8 low power listening modes and 8 corresponding transmit modes. Here, we propose a cross-layer mechanism called Energy Aware Adaptive Low Power Listening (EA-ALPL) that enables each individual sensor node running BMAC to set its own listening mode according to its duty cycle and its number of descendants in the routing tree. EA-ALPL also enables nodes to learn the listening modes of their neighbors and to choose the appropriate transmit mode in order to ensure correct packet reception. We show through deployment experiments that EA-ALPL yields overall power savings ranging between 16% and 55% depending on a node's logical topology position.