Spectrum Sensing in Cognitive Radio Networks : QoS Considerations

摘要

The rapidly growing number of wireless communication devices has led to massive increases inradio traffic density, resulting in a noticeable shortage of available spectrum. To address thisshortage, the Cognitive Radio (CR) technology offers promising solutions that aim to improvethe spectrum utilization. The operation of CR relies on detecting the so-called spectrum holes,the frequency bands that remain unoccupied by their licensed operators. The unlicensed usersare then allowed to communicate using these spectrum holes. As such, the performance of CR ishighly dependent on the employed spectrum sensing methods. Several sensing methods arealready available. However, no individual method can accommodate all potential CR operationscenarios. Hence, it is fair to ascertain that the performance of a CR device can be improved ifit is capable of supporting several sensing methods. It should obviously also be able to select themost suitable method. In this paper, several spectrum sensing methods are compared andanalyzed, aiming to identify their advantages and shortcomings in different CR operatingconditions. Furthermore, it identifies the features that need to be considered while selecting asuitable sensing method from the catalog of available methods.