Research On Spectrum Allocation And Interference Management Of Coexisting Spectrum Access Systems

With the dramatic development of wireless communication technologies,the number of devices in one network has grown exponentially,causing the challenging problem of spectrum shortage.However,the emergence of cognitive radio makes it possible to solve the problem.Due to the scarcity of spectrum,it is normal to share spectrum resources among different access networks and different radio access technologies(RATs).As a result,it becomes an urgent issue to coordinate different spectrum access systems to realize efficient and friendly coexistence.Therefore,this paper mainly investigates the coexistence issues of spectrum access systems,and carries out some constructive solutions from the perspectives of spectrum allocation and interference management.The main contents are as follows:The paper briefly introduces the research progress of coexisting spectrum access systems,summarizes the research status from the perspectives of spectrum allocation and interference management,reviews the current spectrum allocation methods and models,and classifies the coexistence interference between spectrum access systems.For the same radio access technology(RAT)coexisting scenario,a spectrum allocation method based on interference overlap graph is designed.The method includes three steps of interference overlap graph creation,primary channel allocation and bandwidth expansion,which can effectively improve network spectrum satisfaction as well as spectrum efficiency.For the multiple radio access technologies(multi-RAT)coexisting scenario,a spectrum allocation method based on artificial intelligence is designed,which includes featured parameters extraction,scenario recognition and spectrum partitioning strategy selection and channel allocation.A multi-channel ant colony optimization algorithm(Multi-channel ACO)is designed which can improve the network spectrum satisfaction by nearly 30%compared with the traditional spectrum allocation method.In addition,for the problem of coexistence interference between spectrum access systems,this paper focuses on interference management of the multi-RAT coexisting scenario and proposes a guard band configuration method based on interference measurement of adjacent cells.The proposed method can effectively detect the coexisting interference,as well as make interference coordination promptly.Finally,the MATLAB simulation tool is used to verify the proposed spectrum allocation method and interference management method,which proves the feasibility and validity of the proposed methods.