The Research Of Spectrum Sensing Algorithm Based On Stochastic Resonance On Soft Defined Radio

Cognitive Radio (CR) is a new wireless network model, which is proposed to solvethe shortage of spectrum resources by improving the spectrum utilization efficiency.The key idea of CR is dynamic spectrum accessing, which need make sure that thelicensed users will not be harmfully impacted as far as possible when the unlicensedusers are allowed to access the idle spectrum. Therefore, spectrum sensing, which find"empty spectrum", is the key technologies of cognitive radio. As far as possible to avoidharmful interference to the licensed users, spectrum sensing is required to perform welleven in extremely low signal-to-noise ratio (SNR) environments.In this thesis, we mainly investigated the spectrum sensing algorithms based onstochastic resonance, and implemented the algorithms based on software defined radio(SDR) platform. The main content of this thesis divided into three parts:Firstly, the fundamental theory and algorithm of stochastic resonance system areintroduced. The configuration of the system parameters is discussed. Meanwhile, thelimitations of the stochastic resonance with fixed parameter are analyzed. Then, analgorithm based on adaptive stochastic resonance is proposed. A single node spectrumsensing method is further presented based on the proposed adaptive stochasticresonance. This spectrum sensing scheme is the combination of the adaptive stochasticresonance theory and the energy detection algorithm. Simulation is performed toconfirm the performance gain of this proposed algorithm. The simulation results alsoprovide the reference for the implementation based on SDR.Secondly, SR algorithm is implemented based on the software radio platform. Thedesign and implementation of the SR system is provided. The optimization of the keymodules is discussed.Finally, Three spectrum sensing algorithms on SDR platform, including energydetection algorithm, energy detection based on SR algorithm, and energy detectionbased on deviation energy detection with SR algorithm are verified based SDR platform. The simulation and hardware test results are presented, and compared to verify theimplementation.