Evidence-Theory-Based Cooperative Spectrum Sensing With Efficient Quantization Method in Cognitive Radio

Sensing spectra in a reliable and efficient manner is fundamental to cognitive radio (CR). Ensuring cooperation among spectrum sensing devices is an appropriate method when a CR system is under deep shadowing and in a fading environment. In this paper, an enhanced scheme for cooperative spectrum sensing (CSS) based on efficient quantization and the Dempster-Shafer (D-S) theory of evidence is proposed. The proposed scheme includes an effective quantizer for the sensing data by utilizing special properties of the hypothesis distribution under different signal-to-noise ratios (SNRs) of the primary signal. As a result, the required bandwidth for the reporting channel is reduced while the advantage for combinations of the D-S theory is maintained. Simulation results revealed that significant improvements in the CSS gain, as well as a reduction in the system overhead, were achieved.