Research On The Spectrum Allocation Of Cognitive Radio Based On Fairness

With the development of wireless communication technology, the shortage of radio spectrum resources which is the carrier issues are becoming more and more serious. After the research discovery, the cause of the shortage of spectrums is the result of traditional fixed spectrum allocation policy, dynamic spectrum allocation is a good method to solve this problem.In order to ensure the total benefits of the algorithm without serious damaged, and the spectrum allocation fairness between the users can be higher than others, this paper proposes an algorithm of spectrum allocation based on benefit. If some users also assigned the same spectrum and the occurrence of a disturbance, then this algorithm will first view the benefits of these secondary users have been allocated. If the benefits are the same, then the algorithm will allocate the spectrum to the second user which has allocated less spectrums; else the algorithm will allocate the spectrum to the second user which have bigger benefits. Through simulation experiments, comparative benefit fairness to the immune clone selection, color sensitive graph coloring algorithm, proved that this algorithm can improve the fairness of spectrum allocation among users, and the sum of benefit of all second users without serious damaged.In order to improve the spectrum allocation fairness for a period of in a stable environment, this paper put forward an algorithm of spectrum allocation based on fairness. In this algorithm, we proposed a concept of "user priority". User priority is the quantification of the privilege which a second user to a spectrum, it will changed with the time which the user have and the number of the spectrums which the user have allocated. In order to make the secondary users which have been allocated less spectrum have the opportunity to distribute the spectrum, the target function in this algorithm is to maximize user priority, so after a period of time the algorithm will be able to ensure that all the secondary users can distribute the spectrum. By comparing the result of experimental simulation to the immune clone selection and color sensitive graph coloring algorithm, proved that the algorithm can guarantee all secondary users can be assigned to the spectrum in a long enough time.