Iterative Second-Order Moment-Based Spectrum Sensing Algorithm in a Cognitive Radio Context

International audienceThis paper deals with a second-order moment-based spectrum sensing algorithm in a cognitive radio context. Based on a joint and iterative channel and noise variance estimator for OFDM systems, the method accurately estimates the noise variance when the primary user's signal is missing from the given band of frequency. By comparing the estimated noise level with the second-order moment of the received signal, it is possible to detect the presence of the user in the band. The algorithm allows the receiver to perform the joint detection, channel and noise variance estimation. The analytical probability and false alarmprobabilities are proposed, and simulations show the accuracy of the detector. Moreover, the proposed method is tested under a desynchronization constraint