Energy conserving relay assistance for reporting users in cognitive radio networks

In Cognitive Radio (CR) networks, due to fading and shadowing the consistency of single user sensing is deeply affected thereby degrading its detection performance. Cooperative Spectrum Sensing (CSS) paves the way for improving the reliability of sensing in CR networks. In this work, an energy conserving relay assistance method is proposed for modifying the soft fusion with improved Equal Gain Combining (EGC) method to balance the energy consumption among the reporting users. The residual energies of the reporting users are conserved in such a way that reporting is assisted by nearby non reporting users. The overall network energy consumption is also not affected by the proposed method. Also the improved EGC soft fusion method is compared and analysed with the conventional AND hard fusion method and the detection performance is observed to be improved in the improved soft fusion method. In addition to energy conservation, complexity and missed detection analysis are carried out for the proposed algorithm. MATLAB based simulations are performed to compare and justify the algorithm proposed and to estimate the energy conservation analysis.