RW-MAC: An asynchronous receiver-initiated ultra low power MAC protocol for Wireless Sensor Networks

In this paper, we present an asynchronous energy-efficient MAC protocol called RW-MAC for wireless sensor networks. RW-MAC is a receiver-initiated MAC which significantly reduces energy consumption by precisely predicting the re ceiver's wakeup time while still achieves high concurrent performance. To minimize collision, we present an algorithm to stagger the wakeup time of each node in the same collision do main. RW-MAC also tries to optimize the send sequence to maximize the throughput. We have implemented RW-MAC on TinyOS and evaluated its performance on testbeds. The result shows RW-MAC achieves higher concurrent performance and lower energy consumption compared to RI-MAC and X-MAC.