Adaptive Spectrum Selection for Cognitive Radio Networks

While essentially all the frequency is allocated to different wireless applications, observations provide evidence that usage of the spectrum is actually quite limited. Fortunately, cognitive radio technology offers an attractive solution to the reuse of under-utilized licensed spectrum. Therefore, proper channel selection mechanism and channel quality metric are essential to exploit the benefits of spectrum sharing. We propose a free time ratio (FTR) metric that captures channel quality. In addition, we also propose a distributed collaborative sensing scheme to ensure the robustness of the whole network. Simulation results show that the proposed scheme significantly outperforms the existing channel selection methods.