Research On Improved Energy Detection For Spectrum Sensing In Cognitive Radio

Cognitive Radio(CR)technology is widely concerned because it can effectively alleviate the problem of scarcity of spectrum resources.In order to avoid affecting the use of authorized spectrum by authorized users normally and to make cognitive users opportunistically utilize idle licensed spectrums,Spectrum Sensing(SS)plays an indispensable role in the cognitive radio system as the core technology to detect whether there is free spectrum.Among them,the energy detection(ED)method is mainly studied due to its low complexity and high perceived accuracy.However,there are still some limitations on the research of energy detection methods.Firstly,as the mathematical expressions about energy detection are generally more complicated,current research adopts the approximation instead of analytical solutions,but the accuracy is also reduced relatively.Secondly,Conventional Energy Detection(CED)algorithm has further improvement in perceived accuracy.In view of the above improvement suggestions,this paper proposes two improvements to the energy detection algorithm to enhance its perceptual performance:(1)Aiming at the shortcomings that the energy detection method under the small sample only performs an approximate analysis on the detection performance,this paper uses the latest research results of the generalized Marcum Q function to study the energy detection method under small sample conditions,which derives the accurate detection probability closed-form solution in fading channel,and its detection performance is analyzed.Theoretical analysis and simulation results show that the proposed method has a more stable and accurate detection performance in the case of small samples.(2)The energy detection method is improved and combined with the p-norm energy detection method to integrate the energy detection expressions on the AWGN(Additive White Gaussian Noise)channel and the generalized ?-? fading channel.Using the classical ROC(Receiver operating characteristic)curve as the performance evaluation index,CED method and IED method based on p-norm are analyzed and compared.In addition,this paper also studies the energy detection method on the generalized ?-? fading channel,and analyzes its detection performance by the method of AUC(Area Under receiver operating Characteristic).