Selection of spectrum sensing method to enhance Qos in cognitive radio networks

The massively increasing number of wireless communication devices has led to considerable growths in radio traffic density, resulting in a predictable shortage of the available spectrum. To address this potential shortage, the Cognitive Radio (CR) technology offers promising solutions that aim to improve the spectrum utilization. The operation of CR relies on detecting the so-called spectrum holes, i.e., the frequency bands when they are unoccupied by their licensed operators. The unlicensed users are then allowed to communicate using these spectrum holes. Consequently, the performance of CR is highly dependent on the employed spectrum sensing methods. Several sensing methods are already available or literarily proposed. However, no individual method can accommodate all possible CR operation scenarios. Hence, it is fair to ascertain that the performance of a CR device can be improved if it is capable of supporting several sensing methods. Then it should be able to effectively select the most suitable method. In this paper, several spectrum sensing methods are compared and analyzed, aiming to identify their advantages and shortcomings in different CR operating conditions. Furthermore, it identifies the factors that need to be considered while selecting a proper sensing method from the catalog of available methods.