Implementation of Cognitive Radio Technology in WCDMA System

Cognitive radio technology provides high bandwidth to mobile users through exploiting the spectrum effectively by allowing unlicensed users to use wireless architectures for license user In addition to use dynamic spectrum access techniques. Also, there are many challenges facing the cognitive radio technology such as the quality of service for the unlicensed user, changes in the surrounding environment and mobility from frequency to frequency with the requirement not to lose connection. However, cognitive radio technology remains promising and will change the concept of communications very much. In this paper, cognitive radio was applied in the WCDMA system to allow the new user to exploit the licensed spectrum without interference between them, depending on the energy detection technique to detect holes in Spectrum licensed. The performance of secondary users in WCDMA system was evaluated using the MATLAB simulation program and compared with theoretical BER of narrowband BPSK then obtained results in form of tables and error rate curves against signal to noise ratio.