Research On Resource Allocation Of Cooperative Multicast Group Cognitive Radio Network

Continuously growing modern social economy leads to the progress of science and technology,the rapid progress of science and technology promotes the rapid growth of demand for wireless communication services,which requires a lot of spectrum resources.However,the amount of spectrum resources are very limited,new technology and new schemes beyond the traditional communications technology are needed.In order to reasonably solve the problem of lack of spectrum resources,cognitive radio technology is proposed.Cognitive radio since the first proposed is cause a lot of attention,because the licensed frequency band(LFB)communcation is bursty,there is a lot of spectrum hole,technology focuses on making the unlicensed frequency bands(UFB)compatible and coexist with LFB.Without interfering with the normal communication of licensed wireless network,cognitive radio technology can play a greater role in improving the spectrum utilization efficiency and mitigate spectrum resource deficiency.Cooperative transmission technology is different from traditional point-to-point communication and considers transmission models of wireless communication system and other problems from the new perspective of transmission network.The new technology can enhance the transmission capacity of the system through adopting the advantages of diversity and relay,so it is worth further study and full application in wireless communication technology area.This thesis is based on cognitive radio(CR)network,using cooperative multicast technology,optimizing wireless resources,making full use of wireless channels and improves service quality.The main contents of this thesis are as follows:1.On the basis of research at the present stage,a spectrum sensing strategy based on cooperative cognitive radio network is proposed and it allows a game between licensed users and cognitive users over key factors affecting spectrum sensing and spectrum allocation,including detection probability,sensing time,energy threshold,etc,maximize their respective benefits.On the basis of this,game thought is used to analyze the behavioral strategies of licensed users and cognitive users and propose a model framework based on simulation experiment.The model framework can improve the benefits and ultimate benefits of cognitive users on the premise of guaranteeing the interests of licensed users,so it can achieve a win-win situation.2.This thesis researches the optimization of radio resource allocation under the transmission system in CR network and tries to find the solution to signal interference between the master user and the cognitive user,and power limitation of each user.This thesis also introduces the multicast group mechanism based on and intra-group and inter-group cooperative transmission,and describes user transmission rate optimization and power optimal allocation scheme.Then,this thesis also aims to provide more users with higher transmission rate in the power allocation scheme through doing simulation experiment of the optimization scheme and relying on the multicast group cognitive wireless network based on intra-group and inter-group cooperative transmission.When the power is limited,the utilization performance of master user can be guaranteed through weighting factors.