认知无线电终端的改进设计与实现及

ABSTRACTCognitive radio is an intelligent technology used to improve the utilization of spectrumresource.It provides a novel solution for the contradiction between the inefficiency ofspectrum management and the growing demand for spectrum resource.The research of CRhas just begun.So a standardized and modular CR expermental system is designed by ourproject team in order to propose remarkable academic achivements and standards of CR.This thesis mainly focuses on design and implementation of hardware and software of CRterminals and the research on reducing PAPR of CR terminals.The thesis firstly presents the design and implementation of hardware of CR terminals.Anovel hardware architecture of 3DSP+FPGA is proposed to provide a powerful base-banddigital signal processing ability.A high-speed expanding slot connecting the base-band boardand the IF boards is proposed to increase the data rate of CR expermental system.Then thethesis secondly presents the design and implementation of software framework of CRterminals.A realtime multi-task software framework based on DSP/BIOS is proposed toimprove the efficiency of DSP and meet the requirement of timing of all algorithms.Finally,a novel improved clipping algorithm is presented and implemented in CR terminals in orderto solve the problem caused by high PAPR of transmitting signals.This algorithm hasreduced PAPR efficiently and improved the BER performance of CR expermental system.The hardware and software of CR terminal presented in this thesis are already implementedand debugged.The results of debugging are presented at the last of the thesis.Now a newexpermental network and correlative algorithms are being developing based on the CRterminals.KEY WORDS:Cognitive radio;CR terminal;PAPR of OFDM;Improved clipping algorithmTYPE OF THESIS:Applied ResearchFunded by:"The National High Technology Research and Development Program of China(863 Program,No.2005AA123910)","The Science and Technology Plan Foundation of Shaanxi Province"(No.2005K04-G11)and "The Natural Science Fundation of Shaanxi Province(No.2006F41)".