A Novel Adaptive and Cooperative Scheme to Save Energy for Wireless Sensor Network

In this paper, we evaluate the performance of a novel cooperative adaptive relaying scheme called ISDF (Incremental Selective Decode and Forward). We compare the energy efficiency of this underlying scheme with direct transmission (DT), Fixed and adaptive relaying schemes in Wireless Sensor Network (WSN). The system is constrained by a minimum value of Signal-to- Noise Ratio (SNR) and the end-to-end throughput. We consider a three-node cooperative system. The relay is equidistant to the source and destination, and then we study different positions of the latter. The destination receives two copies of the message: one from the source and the other from the relay. Then it combines them by using maximal ratio combining (MRC). The proposed scheme differs from other schemes by the combination of the selective decode and forward scheme with the incremental scheme which requires the presence of a feed-back from the destination. The analysis reveals that the proposed ISDF provides good energy efficiency compared to DT and other cooperative schemes. It also shows that DF cooperative scheme (decode and forward , either with feedback or no, is outperformed by AF (amplify and forward) scheme especially when the relay is placed near the destination.