On the Performance of In-band Sensing without Quiet Period in Ofdm System

In-band spectrum sensing is an effective method of avoiding harmful interference with primary users in cognitive radio. The optimal NoQP Sensing is firstly discussed. Towards a general NoQP Sensing(In-band sensing method without quiet period) problem, we proved that the weighted energy detector is the optimal detector under Neyman-Pearson criterion. The performance of the general NoQP Sensing as well as two NoQP Sensing approaches, Complementary Symbol Couple(CSC) and Self-Signal Suppression(SSS) are analyzed. Based on the optimal NoQP Sensing, we have the performance on detection of the above two methods evaluated. Simulation results show that in the circumstance of IEEE802.22, CSC and SSS have a similar performance, while SSS is more sensitive about the Signal-to-Noise Ratio(SNR).