Adaptive Deactivation of Subcarriers for OFDM based Cognitive Radio

In this paper, an adaptive deactivation method for secondary user (SU) subcarriers is proposed. The deactivation method is applied to reverse link since the receiver uses same cognitive radio (CR) parameters for receiving signals in the reverse link. The proposed method protects the primary user (PU) bands from out of bound (OOB) interference of subcarriers allocated to SUs in the reverse link. The method can be used to prevent the continuous degradation of communication performance by notifying need for reconfiguration to the receiver. In the simulation results, comparison of total interference with a fixed deactivation method is shown.