Indian Journal of Science and Technology

Abstract

In today’s era of wireless and mobile communication, there is unaccustomed increase in number of subscribers which has led to demand of higher data rates. To support higher data rates, enormous bandwidth is required. As the spectrum is limited, problem of bandwidth scarcity has come into picture. Various techniques have been devised to resolve this problem. Cognitive Radio is one of them. Cognitive radio is the name given to the technology which senses the spectrum of primary users and allow the secondary users to send the data if primary users are not sending. Spectrum sensing is the major challenge of CR systems. This paper focuses on the challenges involved in CR systems and various spectrum sensing techniques.

Keywords: Carrier Sense Multiple Access (CSMA), Cognitive Radio (CR), Signal to Noise Ratio (SNR)