Exploiting multiuser diversity for spectrum sensing in cognitive radio networks

We consider wireless system consisting of secondary users equipped with cognitive radios that attempt to access radio spectrum that is not being used by the primary licensed users. To avoid causing harmful interference to the primary users, the secondary users perform spectrum sensing to determine spectrum hole opportunities for channel access. Due to multipath fading, users in the network experience peak channel quality at different times. We propose a cooperative spectrum sensing strategy for cognitive radio networks that exploits the fading diversity among secondary users to improve the probability of correct detection of a primary transmitter. Our simulation results show that the proposed scheme significantly outperforms previous schemes that do not exploit multiuser diversity.