SDN/NFV-based Air Interface For LTE Network

With the rapid development of mobile Internet,data traffic is increasingly augmenting.It is difficult for traditional mobile communication networks to satisfy the present communication requirements due to diverse user businesses and vast amounts of user equipment.The current wireless communication network is closed,rigid and resourcescattered,which will make against network expansion and flexible deployment.Therefore,updating network architecture becomes the emphasis for mobile communication in the future.As key architecture technologies in the fifth generation mobile communication networks,Software Defined Network(SDN)and Network Function Virtualization(NFV)are able to improve the network efficiency effectively and make the whole network highly flexible and easy to expand.Meanwhile,they can create and supply the new network functions quickly according to the ever-changing communication environment to provide users with customized services.Radio access network is the overall network infrastructure and its innovation is the key factor to ensure the efficiency of the entire network.Based on the core thought of SDN and NFV,this paper regards Long Term Evolution(LTE)network as a study basis for the evolution of the fifth generation mobile communication networks and makes research on two parts.The first part is the separation of control and data at the air interface,which is in the part of radio access network for network framework;the second part is slicing technology.This paper firstly studies a new kind of open radio access network framework based on SDN.In this framework,we design a scheme for the separation of control and data at the air interface of LTE network.Then,we build a prototype platform based on LTE network protocol for open radio access network and realize the proposed scheme.The corresponding simulation evaluation proves the feasibility about this scheme.Meanwhile,it also proves that the prototype platform possesses characteristics with the separation of hardware and software in radio access network,centralized control and flexible scheduling.Then,we make a study on the slice of radio access network based on SDN/NFV.On the basis of the research of open radio access network,we build and realize the radio access network slice prototype.Firstly,on the basis of reserving the characteristics of open radio access network,we encapsulate its base station function as well as classify and make the abstraction according to different services for virtual data station.Besides,it can provide the reasonable pre-assignment of resources for creating different network slice instance.Secondly,we create virtual controller that can select the appropriate slice by user business requirement to guarantee the quality of service.Finally,simulation results verify the realization of the network slice based on SDN/NFV in the radio access network.In addition,the prototype platform we built also shows the features of the future mobile communication architecture,such as feasibility,centralized control,easy expansion and customizability.Likewise,the successful construction of prototype architecture platform provides a good experimental basis for future research.