Analysis of a Spectrum Awareness Algorithm for Cognitive Radios

Recently, the technology of cognitive radio (CR) has captured the attention of many researchers in that it promises an effective way of enhancing spectrum usage and solving the problem of heterogeneity of radio devices. For the CR network, a fundamental issue is how to identify the spectrum opportunities. To improve the sensing performance, cooperative spectrum sensing has been proposed. With the conventional sensing method, every cognitive user conducts its individual spectrum sensing by comparing the observation with a pre-fixed threshold and then sends a binary local decision to the common receiver. In the paper, we introduce a novel spectrum scheme based on the trustiness factor (TF) and fussy decision. According to the energy detection, if the energy is located in the energy region with TF=1, then the cognitive user sends 1 bit quantization for reporting its sensing result. Otherwise, the cognitive user sends 2 bits quantization. A final decision therefore is made according to the reporting results. Simulation results show that the proposed sensing scheme outperforms the conventional method in terms of missing probability without noticeable loss in quantization performance.