Design And Implementaion Of Uplink Offloading And Aggregation For 5G

With the development of the Internet of Things and Mobile Internet,more and more applications and services are emerging in an endless stream,which puts forward higher requirements for the wireless network,and people’s demand for 5G(5th Generation)technology is more and more urgent.In order to meet the increasing demand for data traffic and reduce the pressure on existing LTE(Long Term Evolution)cellular network,researchers expect using WiFi(Wireless Fidelity)to offload the traffic of LTE,improving service quality.How to realize the aggregation of LTE and WiFi has attracted widespread attention.In this thesis,we designed and implemented the aggregation system of LTE uplink and WiFi for 5G applications based on SDR(Software Defined Radio).In the first chapter,we introduce the technical background,evolution goals and key technologies of 5G system,and summarize the current situation of integration of LTE and WiFi.Then we describe the LTE and WiFi system architecture and key technical principles in detail in the second chapter,providing a theoretical basis for post-development.The third chapter of this thesis described the design and implementation of LTE uplink transceiver and WiFi transceiver based on OAI(OpenAirInterface).Firstly,the OAI platform is introduced from software to hardware.Then we describe the principle of LTE uplink and WiFi aggregation from the point of view of the user data flow in the protocol stack,and the main work and challenges are summarized.Then we implement the LTE uplink based on OAI,and discuss the realization of WiFi link.Finally we carry out the performance test and analysis of LTE uplink and WiFi link to prove the effectiveness of our design.In the fourth chapter,the aggregation system of LTE uplink and WiFi link mentioned above is successfully built up and the performance is tested.Firstly we design the virtual network card,which is the interface between application layer and PDCP(Packet Data Convergence Protocol).Then we describe the offloading scheme and procedures in terminal transmitter,and the aggregation algorithm in the base station receiver.Finally we conduct the performance test and analysis of the system from the aspect of the work scene,system throughput and memory occupancy.In this thesis,we realized the heterogeneous network fusion of LTE and WiFi based on SDR.Therefore,the scheme and results proposed in this thesis could provide some pratical reference for the development of LTE and WiFi heterogeneous integration in the future wireless network.