Research Of Cooperative Spectrum Sensing And Allocation Of Cognitive Radio Based On Invasive Weeds Algorithm

One of the problems faced and needs to be solved nowadays in communication services is spectrum resources under utilized,which directly restricts the development of future wireless communication services. With innovation and technological advancing, the demand for wireless communications is increasing, but the limited spectrum resources become increasingly scarce and precious, how to improve the spectrum utilization is imminent.As an intelligent spectrum sharing technology, Cognitive Radio can take second use of the idle spectrum and opened up a new way for easing tensions of spectrum resources and low utilization of spectrum resources,which becomes the focus of research,by sensing the environment of wireless communication and allocating flexible. Spectrum sensing and spectrum allocation are two key technologies of Cognitive Radio, which can improve spectrum utilization. This paper studies the intelligent algorithms application in spectrum sensing and spectrum allocation.First, this paper introduces the research background of Cognitive Radio, describes the basic theoretical knowledge and allocation of spectrum sensing, analysisthe existing spectrum sensing methods and allocation mechanisms, explores the cognitive network of several traditional single node spectrum sensing techniques and the performance of cooperative spectrum sensing technology, and some of the major current spectrum allocation mode as well.Second, by linear weighted cooperative spectrum sensing model, this paper studies method for solving the weight vector based on the right bias correction factor (MDC), and spectrum sensing scheme based on improved Shuffled Frog Leaping Algorithm (SFLA). After the research of Weeds Algorithm, for the problem of a given probability of false alarm that how to maximize the probability of detection, incorporats the working principles of existing Invasive Weeds Algorithm (IWO) in the model, after improving them. Propose cooperative spectrum sensing scheme based on modified optimization of Invasive Weed algorithm(MIWO). Collaborates the feasible spectrum solutionwith sensing model corresponding weights, maximize the probability of detection, by finding the minimizing the fitness function optimal weight vector, and analysis the comparative simulation with SFLA algorithm.At last, by spectrum sensing techniques obtaining the licensed idle bands, after studying the spectrum allocation method of the Genetic Algorithm (GA), Particle Swarm Optimization(PSO), for rational allocation of free spectrum resources, proposed a allocation method of Cognitive Radio spectrum based on binary weeds, to maximize network efficiency and improve the fairness among users while each cognitive spectrum is allocated. Taking full advantages of the diversity of its search algorithm, fast convergence, strong search capabilities, etc, and comparatively analysis the simulation with genetic algorithms, particle swarm optimization.