A REVIEW ON SENSING OF SPECTRUM IN COGNITIVE RADIO NETWORKS

Abstract: The major requirement for communication is the Bandwidth which is very limited. And for effective utilisation of the bandwidth Cognitive Radios (CR) are used which are is also called Software Defined Radios with inbuilt intelligence, which are used to reduce the burden in the electromagnetic Spectrum. The cognitive radio efficiently allocates the License Bands to Unlicensed user when the licence band is not being used the licensed user which is called the primary user (PU) and the Cognitive Radio user which is called the Secondary User (SU) which may co-exist together in the spectrum bandwidth provided that the secondary user does not interfere with the primary user in the communication process. This is done by the process of Spectrum Sensing which is the very important part for any Cognitive Radio and for the Sensing various techniques are used. This paper presents the concept of Cognitive Radio network and the review of the two techniques which are Cooperative and Non-Cooperative spectrum sensing techniques the paper also highlights the main advantage as well as disadvantage of cognitive radio networks and its future scopes.

Keywords: PU (Primary user), SU(Secondary User), CRN(Cognitive Radio Network), Spectrum Prediction, Activity Modelling , CR(Cognitive Radio)