A Resource Scheduling Scheme Utilizing Grey Space Spectrums for OFDM Based Cognitive Radio Systems

In this paper, we proposed a resource scheduling scheme for OFDM based Cognitive Radio (CR) systems. The available spectrum resources detected by certain sensing method are separate into "white space" and "grey space". Different from other researches which aim at only allocating white space spectrums to cognitive users, our discussion present a proper solution to make use of grey space spectrums. When the white space spectrums are not sufficient for all users, the grey space will be deployed for the non real-time services while a simple subcarrier selection method is adopted in order to limit the interference to the primary user and meet the BER need for transmission. This scheme gives a method to utilize grey space spectrum appropriately and the simulation result reveals that our proposed scheme could increase the throughput of system and improve the QoS guarantee of non-real-time services.