The Study Of Spectrum Allocation Algorithm In Cognitive Radio Network

With the development of wireless communications, the demand for spectrum resources is growing, and the traditional method of spectrum allocation is challenged greatly with the reason of low utilization of the spectrum. CR (cognitive radio) technology is considered to be the best solution to solve this problem. One of the key technologies is open spectrum allocation. The purpose of spectrum allocation is to choose and use the"free spectrum"reasonably, in order to maximize the use of available spectrum resources and ensure the fairness of the allocation.This paper mainly researches the spectrum allocation algorithm in CR network. This article first describes the concept of cognitive radio, the key technologies, the basic principles and models of the spectrum allocation algorithm. Then this dissertation studies the list-coloring algorithm and color-sensitive graph coloring (CSGC) algorithm in depth based on graph coloring model.Next, three classical algorithms based on list-coloring algorithm are analyzed and simulated to show their good performance and weakness. Then in the study and comparison of algorithm theory and labeling system based on CSGC algorithm, an improved spectrum allocation algorithm based on proportional fairness is proposed. An adjusting factor of channel quantity is introduced based on traditional labeling system, which has effective inhibitory functions for nodes who occupy high priority throughout and provides the opportunities of channel assignment for more nodes. Simulation results indicate that this algorithm can improve the users'fairness of service capacity and bandwidth gain compared with CSGC algorithm. At last, the parallel algorithm was introduced in order to reduce the communication costs.