A design of robust energy detector for cognitive radios

Cognitive radio has been considered as the key to promote the efficient use of the spectrum by exploiting idle spectrum bands. Energy detection method is the most commonly used method for spectrum sensing in cognitive radios because of its simplicity and good performance. However, the performance of energy detector deteriorates rapidly if the noise power is fluctuating. In order to cope with noise uncertainty, this paper proposes a robust energy detection method based on Huber's mixture model. The proposed robust energy detector performs amplitude-limiting operation before energy detection and in fact is an improved energy detector. A detailed performance analysis is given on this method and simulation results are presented to show the validity and the superiority of the proposed method.