Unicast Routing Protocols to Reduce Electric Energy Consumption in Wireless Ad-hoc Networks

In wireless ad-hoc networks, messages have to be energy-efficiently exchanged among neighboring nodes. In our previous studies, the reactive type EAO (Energy-Aware One-to-one routing) and LEU (Low-Energy Unicast Ad-hoc routing) protocols are proposed to unicast messages to the destination node. In the EAO protocol, the total electric energy of nodes and delay time from a source node to a destination node can be reduced compared with the ESU and AODV protocols. However, a source-to-destination route may not be found if the communication range of each node is shorter. In this paper, we newly proposed an IEAO (Improved Energy-Aware One-to-one routing) protocol to overcome the difficulties of the EAO protocol. Here, after a shortest route is found to the destination node, a more energy-efficient prior node is found in nearest neighbor of each node starting from the destination node. In this paper, a neighbor node which has an uncovered neighbor node is selected as a prior node for each node to make a route. In the evaluation, we show the number of nodes in a source-to-destination route can be reduced and a route can be found even in shorter communication range in the IEAO protocol compared with the LEU and EAO protocols.