Cell based energy density aware routing: a new protocol for improving the lifetime of wireless sensor networks

Wireless sensor networks have unique features not shared by mobile ad-hoc networks. Taking these features into consideration, we propose a new routing protocol specifically designed for wireless sensor networks. This protocol, referred to as cell based energy density aware routing (CEDA), divides a sensor field into uniform cells, thereby reducing energy consumption caused by sensor data flooding. Energy density, a novel routing metric, is used to avoid forwarding packets to subareas whose nodes have lower residual energies. By ensuring fair energy consumption of sensor nodes, CEDA makes it possible for monitoring stations to monitor all subareas for longer periods of time. Simulations were carried out to compare the performance of CEDA with those of several existing protocols for wireless networks or sensor networks. The time required for a subarea to run out of energy, called the lifetime of that area, is measured in the simulations. The simulation results show that CEDA gives a longer lifetime than the existing routing protocols. In addition, it is proved that CEDA guarantees the maximum hop count regardless of the node density, and hence does not suffer from unpredictable delays.