【作者】 李威；

【导师】 郭彩丽；

【作者基本信息】 北京邮电大学 ， 电子与通信工程（专业学位）， 2022， 硕士

【摘要】 在当前的移动通信网络中,空中接口资源依然是最紧缺的资源,并且在智能终端数量激增、数据业务种类繁多、小数据包业务占比日趋增长的大环境下,未来的5G通信系统需要支持高效的小数据传输与当前的蜂窝网络无缝连接,且在不同的无线传输技术之间快速灵活地切换。这种小数据包业务具有两个明显特点:其一是小数据包总的流量很小,但每次伴随的信令比重很大,给系统带来了大量的资源浪费;其二是该业务要求用户永远在线且具有心跳现象,导致网络中在线用户数量巨大,多用户接入时将引入时间延迟。为了解决5G和B5G系统小数据传输效率问题,非激活状态下基于随机接入的小数据传输增强技术获得了广泛研究。因此,研究5G通信系统中小数据传输增强技术对缓解资源浪费、降低时延有着重要意义。本论文选题来自科技部重点研发计划“面向B5G和6G公共服务平台建设”,基于开发空中接口(OpenAirInterface,OAI)设计并实现了一个适用5G通信系统中小数据传输增强的半实物仿真平台,进一步基于该平台对5G通信系统的小数据传输增强技术进行仿真验证和性能分析,为标准化工作提供理论参考依据。本论文完成的主要工作如下:1、基于5G随机接入的小数据传输增强技术半实物仿真设计。本论文首先进行了需求分析和总体设计。并根据5G通信系统中基于随机接入的小数据传输增强技术的功能需求,先对基于四步随机接入的小数据包传输增强进行设计,然后对基于两步随机接入的小数据传输增强进行设计。重点设计了物理层功能模块、MAC层功能模块和PHY/MAC层接口模块,使得半实物平台中的基站和终端两个网元能够实现高效的小数据传输增强功能。2、基于5G随机接入的小数据传输增强技术半实物仿真实现与验证。首先在模块设计思想的指导下,完成了基于四步和两步随机接入的小数据传输增强半实物仿真的开发实现,实现过程涉及基站和终端侧网元的多个协议层、多个信道以及层间交换的接口。其次从信令面和数据面开展了半实物仿真平台的功能验证和性能评估。仿真结果表明,该平台能够在向下兼容原有平台功能的基础上完成基于5G随机接入的小数据传输增强的通信仿真,并且在小数据包传输时延和信令开销方面有明显的提升。证明了本论文所设计的半实物仿真平台的可行性,本论文的开发成果为项目后续研发提供了测试和实验平台。更多还原

【Abstract】 In the current mobile communication network,air interface resources are still the most scarce resource.At the same time,in the environment of the surge in the number of intelligent terminals,the variety of data services,and the growing proportion of small data packet services,the future 5G communication system needs Supports efficient small data transmission seamlessly with current cellular networks and fast and flexible switching between different wireless transmission technologies.This kind of small data packet service has two obvious characteristics.One is that the total traffic of small data packets is very small,but each time the accompanying signaling accounts for a large proportion,which brings a lot of waste of resources to the system;the other is that this service Users are required to be always online and have a heartbeat phenomenon,resulting in a huge number of online users in the network,and a time delay will be introduced when multiple users access.In order to solve the problem of small data transmission efficiency in 5G and B5G systems,the enhancement technology of small data transmission based on random access in the inactive state has been widely studied.Therefore,it is of great significance to study the small data transmission enhancement technology in the 5G communication system to alleviate the waste of resources and reduce the delay.The topic of this paper comes from the key research and development plan of the Ministry of Science and Technology "Construction of B5G and 6G Public Service Platforms".Based on the development of the air interface(OpenAirInterface,OAI),a hardware-in-the-loop simulation platform suitable for small and medium data transmission enhancement in 5G communication systems is designed and implemented.Based on this platform,the simulation verification and performance analysis of the small data transmission enhancement technology of 5G communication system are carried out,which provides a theoretical reference for standardization work.The main work of this paper is as follows:Firstly,design of hardware-in-the-loop simulation platform for small data transmission technology based on 5G random access.In this paper,the requirement analysis and overall design are firstly carried out,and according to the functional requirements of the small data transmission enhancement technology based on random access in the 5G communication system,the small data packet transmission enhancement based on four-step random access is designed first.The design is based on the enhancement of small data transmission of two-step random access,focusing on the design of the physical layer function module,the MAC layer function module and the PHY/MAC layer interface module,so that the two network elements of the base station and the terminal in the hardware-in-the-loop platform can achieve high efficiency small data transfer enhancements.Secondly,implementation and verification of the hardware-in-theloop simulation platform based on 5G random access enhancement technology for small data transmission.First,under the guidance of the module design idea,the development and realization of the enhanced hardware-in-the-loop simulation of small data transmission based on fourstep and two-step random access is completed.The realization process involves multiple protocol layers and multiple channels of network elements on the base station and terminal side.And the interface exchanged between layers.Secondly,the functional verification and performance evaluation of the hardware-in-the-loop simulation platform are carried out from the signaling and data planes.The simulation results show that the platform can complete the enhanced communication simulation of small data transmission based on 5G random access on the basis of being backward compatible with the functions of the original platform,and has significantly improved the transmission delay and signaling overhead of small data packets.The feasibility of the hardware-in-the-loop simulation platform designed in this paper is proved,and the development results of this paper provide a test and experimental platform for the follow-up research and development of the project.更多还原