Resistance to Interference for OFDM-Based Cognitive Radio Systems

Based on zero-padding idea, we propose a simple way to resist the interference between licensed users and cognitive users for cognitive radio (CR) systems adopting orthogonal frequency division multiplexing (OFDM) technique. Different from the traditional methods, the presented interference resistance way for OFDM-based CR systems only shuts off the sub-channels occupied by the licensed users and continues to work in the remainder sub-channels at the cost of lower data rate, which need not shift all communication bands. Simulation results show that the proposed method can obtain desirable resistance to the interference between licensed users and cognitive users and possess lower realization complexity for OFDM-based CR systems.