Spectrum Sharing In Cognitive Radio Networks

According to Federal Communication Commission (FCC), more than 70% of the available spectrum is not utilized optimally. Cognitive radio is a better technique to fulfill the utilization of radio frequency spectrum. Both licensed and unlicensed users can use the frequency spectrum using cognitive radio technique. Licensed users are the primary users and unlicensed users are the secondary users. Secondary user requests the primary user for some amount of spectrum. Primary user allocates the spectrum to the secondary users by itself without degrading its own performance using spectrum sharing techniques. This paper deals with different types of spectrum sharing techniques.