Spectrum Sensing Techniques applied in Cognitive Radio Networks- A Comparison

Abstract Cognitive Radio (CR), a radio with built-in intelligence, became a necessity to overcome the scarcity of available electromagnetic radio spectrum. It efficiently allocates the licensed bands to the unlicensed users when licensed bands are not in use, taking into concern the interference limit. In this radio network, the first and the most important task is the Spectrum Sensing. This is the technique of sensing or detecting the available licensed bands that can be made use of by the unlicensed users. As spectrum sensing is a major functional block of cognitive networks, it faces certain challenges also. This paper presents the concept of Cognitive radio networks and a literature survey of the two main techniques of spectrum sensing i.e. Cooperative and non – Cooperative spectrum sensing. It also highlights their respective advantages and disadvantages. Based on the study, some generic conclusions have been taken. Keywords: Cognitive Radio (CR), licensed band, Spectrum Sensing, Cooperative, Non-cooperative spectrum sensing.