Periodic spectrum sensing parameters optimisation in cognitive radio networks

Abstract

Spectrum sensing is one of the main features of cognitive radio that enables secondary users (SUs) to detect spectrum holes. In this study, the authors propose a more realistic measure of interference which is based on the collision between secondary and primary signals. Considering the single SU scenario, the authors find optimal sensing time, transmission time and energy detector threshold to maximise its efficiency while keeping its interference on primary users below a certain threshold. Then, cooperative sensing schemes in a centralised network are investigated in which, the authors derive the optimal cooperation method in the Neyman–Pearson framework and subsequently propose simpler suboptimal cooperative schemes. Furthermore, the authors formulate the limited feedback scheme that uses a two bit quantiser for energy detectors, and compare its performance with other cooperation schemes and it will be shown to have the closest performance to the optimal scheme among all other mentioned methods.