An Energy-efficient Communication Protocol using Spatial Groups for Wireless Sensor Networks

[[abstract]]In Wireless sensor networks, sensor nodes are deployed to monitor some environmental parameters and send them to the base station. The energy of sensor nodes is a critical resource in wireless sensor network. It is important to prolong the lifetime of the network. In order to reduce network overall energy consumption, some research presents schemes to turn off part of sensor nodes with guarantee of sufficient sensing coverage and reliability. To find out the redundant nodes, the scheme needs to equip sensor nodes with GPS or directional antenna which is however costly. We propose a distributed approach to turn off more nodes at a slight cost of coverage. We divide nodes into several groups according to their first association with some random selected node. Those sensors in the same group are scheduled so that only one node is active and responsible for monitoring environmental parameters every time. Based on their residual energy, routing paths are built to connect those active nodes to the base station. Simulation results show that our approach can extend the network life time only at a little cost of coverage in the high density topology network.