Power Allocation and Partner Selection in Energy Efficient Cooperative WSN

Wireless sensor networks are composed of many small distributed battery–powered sensor nodes, so reducing the energy consumption in each node to increase network lifetime is essential. One method that significantly reduces the energy consumption in each node is cooperative communication. In this paper, we investigate power allocation to one source node and partner node(s) in two scenarios for an energy efficient cooperative communication. In both of them, we use a cluster of partners and we want to minimize energy consumption. In the first scenario, we use two partners and allocate power to them according to a search based optimization problem and compare its performance with the case of using one partner. In the second one, we select one partner according to its channel gain to reduce packet failure ratio. It is also shown that using two partners instead of one can often increase the performance of the system in the first scenario. Furthermore, it is shown that increasing cluster size can decrease packet failure ratio, significantly.