Implementation of TEAN-sleep for Wireless Sensor Networks

Wireless Sensor Network have many potential applications, including environmental monitoring and threat surveillance, among many others. Sensor nodes are limited in processing capabilities, radio range, storage but most importantly in energy. When a node´s energy is exhausted, the node can no longer provide sensor data to the network, nor can it forward data from other nodes. This can result in a network partition. One way a node may extend its lifetime is by the use of sleep. In many of the applications of WSNs the nodes are idle most of the time until an event occurs and information needs to be transmitted. A node is able to save energy while idle by sleeping. Topology and Energy Adaptive, Non-synchronous (TEAN) sleep provides the nodes in a network a mechanism to save energy by sleeping while also keeping a connected network. In this paper, we present an implementation of TEAN-sleep in tinyOS on a 50 node test bed of Crossbow TelosB motes. Preliminary test results show significant improvement in network lifetime when TEAN-sleep is engaged, with insignificant degradation of connectivity.