Optimal Resource Allocation For The Cognitive Radio Networks With Spectrum Leasing Mode

Cognitive radio technology has a very broad development prospect in improving the utilization of wireless spectrum and improving the tension of spectrum resources.Wireless communication networks based on relay technology have greater coverage and more efficient information transmission.Combining the advantages of cognitive radio technology and relay technology,a new network model can be constructed,which is a cognitive wireless network based on spectrum leasing mode.In the network model,the secondary users obtain the right to use the licensed spectrum by helping the primary user to relay the information.This cooperation will make the primary user and the secondary users achieve a win-win situation.However,this model also faces some problems and challenges: how to suppress the selfish behavior of secondary users,so as to ensure that the cooperative win-win relationship between primary user and secondary users is not destroyed;how to ensure that the system is well maintained in an actual complex communication environment.And how the model is combined with the prefaced techniques to improve the communication performance of the model and expand the scope of application of the model.In response to the above questions,this paper proposes the following solutions:(1)A new form of evaluation coefficient is proposed to reflect the behavior of each secondary user.Each secondary user takes the evaluation coefficient into consideration of its optimization problem and makes a resource allocation scheme that conforms to the system fairness,thereby achieving the purpose of suppressing the selfish behavior of the secondary users.At the same time,the problem of optimal allocation of resources in the system is constructed as the game problem between primary user and secondary users.The evaluation process is combined with the game process to achieve the optimal allocation of system resources on the premise of guaranteeing the fairness of secondary users.(2)Considering the complexity and time-varying of wireless communication environment,a robust optimal allocation algorithm for system resources is proposed.We modeled the channel as Rayleigh fading.Then,the uncertainties of channel gain are reflected in the outage probability of communication.By taking the outage probability constraint into account the resource optimization problem of the system,the robustness of the system in complex communication environment can be guaranteed.(3)Combining cognitive radio technology based on spectrum leasing mode,wireless sensor network and wireless energy transmission,a research model with great practical application value is constructed.According to the characteristics of the model,a new heuristic relay configuration rule is proposed to solve the matching problem of multiple primary users and multiple secondary users,and an alternating optimization method is used to optimize the joint resource allocation of subcarriers,power and time in the system.