A New Energy Efficient Protocol for Minimizing Multi-Hop Latency in Wireless Sensor Networks

In wireless sensor networks, efficient usage of energy helps in improving the network lifetime. As the battery of a sensor node, in most cases, cannot be recharged or replaced after the deployment of the sensors, energy management becomes a critical issue in such networks. In order to detect an event, a sensor network spends majority of the time in monitoring its environment, during which a significant amount of energy can be saved by placing the radio in the low-power sleep mode. This can be achieved by using a dual frequency radio setup. However, such energy saving protocols increase the latency encountered in setting up a multihop path. We, in this paper, propose a reservation scheme, latency minimized energy efficient MAC protocol (LEEM), which is a novel hop-ahead reservation scheme in a dual frequency radio to minimize the latency in the multihop path data transmission by reserving the next hop's channel a priori. Thus, in a multihop sensor network, a packet can be forwarded to the next hop, as soon as it is received by a sensor node, which helps in eliminating the delay incurred for setting up the path. Simulation results show that LEEM consumes lesser power and reduces end-to-end latency by around 50% than that of the existing schemes