Spectrum Sensing For DTMB Signal And Its Implementation On USRP

With the innovation and optimization of the mobile terminals, the mobile terminals are used more and more frequently. As a result, more spectrum resources are needed to provide for mobile terminals. Nevertheless, the mobile communication spectrum resources of CHINA increase slowly and cannot cope with the growing communication demands, on one hand. On the other hand, the new spectrum resources allocated to mobile communication are most spectrum resources of high band. Since the higher the spectrum band is, the shorter the communication distance will be, thus, more additional nodes are needed to relay communications which will reduce the mobility of the terminal. Considering the above two points, to deal with the rapidly growing demands of mobile communications, not only more spectrum resources are needed, but also high-quality spectrum resources with low-frequency are needed.First, the spectrum resources licensed to televisions are under utilization and the TV spectrum bands are the high-quality spectrum resources required by mobile communications. Therefore, the cognitive radio technology is considered to allow mobile terminals to reuse the spectrum bands of television. Furthermore, the spectrum sensing algorithm for digital television signal is proposed. By analyzing the characteristics of DTMB signal, the corresponding sensing algorithm is designed which achieves a good performance under low SNR.In this thesis, software radio technology is introduced to validate the proposed algorithms which means that the spectrum sensing method will be realized and verified on hardware platform. The basic principles and techniques of the USRP software radio platform will be introduced first. Then, the GNU Radio which is the development environment of USRP is presented. Finally, the proposed spectrum sensing algorithms will be realized and verified on the USRP platform and it achieves a good performance as well.