Performance Analysis of Wireless Sensor Networks with Non-coherent Cooperative Relay Nodes

In this paper, a non-coherent cooperative relay node selection scheme for the wireless sensor networks has been proposed. The motivation for adopting non-coherent combining scheme is due to low complexity in a sensor node for signal detection. Its performance was evaluated in terms of the transfer capacity, the energy consumption of the interested node, and its validity of a cooperative node selection. The cooperative relay node selection was made in order to improve the intermediate wireless link between the source and the destination nodes. The energy factor was considered as a performance index of the proposed scheme. The energy factor for the interested sensor node was obtained by combining the signal of the direct path and that of the relay path. The numerical results showed that the proposed scheme can improve the transfer capacity and the energy reduction of the interested node. Moreover, it can prevent the ineffective combining of the cooperative relay node which can cause the loss of the transfer capacity and the energy consumption.