Institute of Electrical & Electronic Engineers
Cognitive Radio (CR), as the novel approach to improve the utilization of the available radio spectrum is introduced under the constraint that the current authorized users are sufficiently protected against any harmful interferences. However, there are many challenges associated with detection of the Primary Users (PUs) which need to be addressed carefully. One of the most important challenges in CR networks is how to sense the existence of a PU transmission. The Secondary Users (SUs) are required to sense the channels, and once the PUs are found, they are required to vacate the channel in a specific amount of time.