Research Of Key Technology Of Cognitive Radio

Along with the development of communication technologies, industrialists hope that the radio devices have the adaptively intelligent functions. On the other hand, there is spectrum scarcity of frequencies that can be economically used for wireless communications. This concern has arisen from the intense competition for use of spectra at frequencies below 3 GHz. But actual measurements taken by FCC (Federal Communications Commission) are believed to be typical and indicate low utilization. In order to utilize these spectrum'white spaces', the FCC has issued a Notice advancing Cognitive Radio (CR) technology as a candidate to implement negotiated or opportunistic spectrum sharing.Cognitive radio system is the expansion of the Software Radio system. It offers the opportunity to use dynamic spectrum management techniques to sense the environment around the receiver, help prevent interference, adapt to immediate local spectrum availability by creating time and location dependent in"virtual unlicensed bands". This paper focused on the key technologies of Cognitive Radio, and given a realization of cognitive radio receiver. Each module of the receiver system is designed in this paper. In the last part of this paper, the most important key technology, spectrum sensing, was simulated by using Matlab, and the control program of spectrum sensing was also designed by using C programming language.