With the explosive increasing number of connecting devices such as smart phones, vehicles,drones, and satellites in the wireless networks, how to manage and control such a huge number of networking nodes has become a ...With the explosive increasing number of connecting devices such as smart phones, vehicles,drones, and satellites in the wireless networks, how to manage and control such a huge number of networking nodes has become a great challenge. In this paper, we combine the advantages of centralized networks and distributed networks approaches for vehicular networks with the aid of Unmanned Aerial Vehicle(UAV), and propose a Center-controlled Multihop Wireless(CMW) networking scheme consisting of data transmission plane performed by vehicles and the network control plane implemented by the UAV.Besides, we jointly explore the advantages of Medium Access Control(MAC) protocols in the link layer and routing schemes in the network layer to facilitate the multi-hop data transmission for the ground vehicles.Particularly, the network control plane in the UAV can manage the whole network effectively via fully exploiting the acquired network topology information and traffic requests from each vehicle, and implements various kinds of control based on different traffic demands, which can enhance the networking flexibility and scalability significantly in vehicular networks.Simulation results validate the advantages of the proposed scheme compared with existing methods.展开更多
针对5G新空口-车联网(New Radio-Vehicle to Everything,NR-V2X)场景下车对基础设施(Vehicle to Infrastructure,V2I)和车对车(Vehicle to Vehicle,V2V)共享上行通信链路的频谱资源分配问题,提出了一种联邦-多智能体深度Q网络(Federated...针对5G新空口-车联网(New Radio-Vehicle to Everything,NR-V2X)场景下车对基础设施(Vehicle to Infrastructure,V2I)和车对车(Vehicle to Vehicle,V2V)共享上行通信链路的频谱资源分配问题,提出了一种联邦-多智能体深度Q网络(Federated Learning-Multi-Agent Deep Q Network,FL-MADQN)算法.该分布式算法中,每个车辆用户作为一个智能体,根据获取的本地信道状态信息,以网络信道容量最佳为目标函数,采用DQN算法训练学习本地网络模型.采用联邦学习加快以及稳定各智能体网络模型训练的收敛速度,即将各智能体的本地模型上传至基站进行聚合形成全局模型,再将全局模型下发至各智能体更新本地模型.仿真结果表明:与传统分布式多智能体DQN算法相比,所提出的方案具有更快的模型收敛速度,并且当车辆用户数增大时仍然保证V2V链路的通信效率以及V2I链路的信道容量.展开更多
车路协同是信息通信、智能汽车、交通运输和交通管理等行业深度融合的新型产业业态,处于人工智能、5G和交通三大国家战略的交汇点。5G V2X无线通信技术作为关键赋能型技术,将有助于构建“路-云-车-人-网”协同的车联网生态体系。该文首...车路协同是信息通信、智能汽车、交通运输和交通管理等行业深度融合的新型产业业态,处于人工智能、5G和交通三大国家战略的交汇点。5G V2X无线通信技术作为关键赋能型技术,将有助于构建“路-云-车-人-网”协同的车联网生态体系。该文首先介绍车路协同系统的定义、主要建设内容及其典型应用场景。其次以应用牵引,针对5G新空口-车用无线通信(NR-V2X)技术中的直连通信应用于自动驾驶场景的具体需求进行研究,给出不同业务场景下对通信性能和安全的需求说明。最后,针对车路协同系统低时延、高可靠和高并发的系统需求,分析5G NR V2X物理层、资源分配、拥塞控制和Qos与安全设计的相关原理。展开更多
V2X(vehicle to everything)通信是车联网中实现环境感知、信息交互与协同控制的重要关键技术。大唐电信科技产业集团最早提出并由中国企业主导的LTE-V2X国际标准作为其中的主流技术之一,能够在高速移动环境中提供低时延、高可靠、高速...V2X(vehicle to everything)通信是车联网中实现环境感知、信息交互与协同控制的重要关键技术。大唐电信科技产业集团最早提出并由中国企业主导的LTE-V2X国际标准作为其中的主流技术之一,能够在高速移动环境中提供低时延、高可靠、高速率、安全的通信能力,并能够最大程度利用TD-LTE已部署网络及终端芯片平台等资源。首先介绍了LTE-V2X的关键技术,并与IEEE 802.11p进行了比较;进而介绍了LTE-V2X的标准研究及其演进以及相关的产业发展和示范应用;最后展望了LTE-V2X的发展策略及其向5G NR-V2X的技术演进等,并提出了相关政策建议。展开更多
V2X(vehicle to everything)车联网指车与车、车与路、车与人、车与云等直接互联,被普遍认为是汽车未来发展的必然趋势•随着车联网化程度的提升,车由以往孤立的封闭空间变成万物互联的一个网络节点,如何保证车辆通信安全显得尤为重要.V2...V2X(vehicle to everything)车联网指车与车、车与路、车与人、车与云等直接互联,被普遍认为是汽车未来发展的必然趋势•随着车联网化程度的提升,车由以往孤立的封闭空间变成万物互联的一个网络节点,如何保证车辆通信安全显得尤为重要.V2X CA(certification authority)证书可有效保证车联网通信链路安全,但由于尚未形成规范标准,行业推广和认识程度不够,且证书应用主要体现在通信数据流中,无法让人直观了解其工作原理.为此,提出了基于V2X CA的车联网微缩展示平台,从基础设施层、数据资源层、系统应用层和场景演示层分别进行了介绍.针对V2X实际场景,分别设计了证书申请、车车交互、车路交互、车人交互、车云交互、证书撤销6类场景下CA证书的交互验证,同时结合可视化系统对证书交互过程进行了同步形象展示,有助于V2XCA在车联网上的推广应用.展开更多
基金supported in part by the National Natural Science Foundation of China under Grant 62071283,Grant 61771296,Grant 61872228 and Grant 62271513in part by the Natural Science Basic Research Plan in Shaanxi Province of China under Grant 2018JQ6048 and Grant 2018JZ6006+3 种基金in part by Shaanxi Key Industrial Innovation Chain Project in Industrial Domain under Grant 2020ZDLGY15-09in part by Guang Dong Basic and Applied Basic Research Foundation under Grant 2021A1515012631in part by China Postdoctoral Science Foundation under Grant 2016M600761in part by the Fundamental Research Funds for the Central Universities under Grant GK202003075 and Grant GK202103016。
文摘With the explosive increasing number of connecting devices such as smart phones, vehicles,drones, and satellites in the wireless networks, how to manage and control such a huge number of networking nodes has become a great challenge. In this paper, we combine the advantages of centralized networks and distributed networks approaches for vehicular networks with the aid of Unmanned Aerial Vehicle(UAV), and propose a Center-controlled Multihop Wireless(CMW) networking scheme consisting of data transmission plane performed by vehicles and the network control plane implemented by the UAV.Besides, we jointly explore the advantages of Medium Access Control(MAC) protocols in the link layer and routing schemes in the network layer to facilitate the multi-hop data transmission for the ground vehicles.Particularly, the network control plane in the UAV can manage the whole network effectively via fully exploiting the acquired network topology information and traffic requests from each vehicle, and implements various kinds of control based on different traffic demands, which can enhance the networking flexibility and scalability significantly in vehicular networks.Simulation results validate the advantages of the proposed scheme compared with existing methods.
文摘针对5G新空口-车联网(New Radio-Vehicle to Everything,NR-V2X)场景下车对基础设施(Vehicle to Infrastructure,V2I)和车对车(Vehicle to Vehicle,V2V)共享上行通信链路的频谱资源分配问题,提出了一种联邦-多智能体深度Q网络(Federated Learning-Multi-Agent Deep Q Network,FL-MADQN)算法.该分布式算法中,每个车辆用户作为一个智能体,根据获取的本地信道状态信息,以网络信道容量最佳为目标函数,采用DQN算法训练学习本地网络模型.采用联邦学习加快以及稳定各智能体网络模型训练的收敛速度,即将各智能体的本地模型上传至基站进行聚合形成全局模型,再将全局模型下发至各智能体更新本地模型.仿真结果表明:与传统分布式多智能体DQN算法相比,所提出的方案具有更快的模型收敛速度,并且当车辆用户数增大时仍然保证V2V链路的通信效率以及V2I链路的信道容量.
文摘车路协同是信息通信、智能汽车、交通运输和交通管理等行业深度融合的新型产业业态,处于人工智能、5G和交通三大国家战略的交汇点。5G V2X无线通信技术作为关键赋能型技术,将有助于构建“路-云-车-人-网”协同的车联网生态体系。该文首先介绍车路协同系统的定义、主要建设内容及其典型应用场景。其次以应用牵引,针对5G新空口-车用无线通信(NR-V2X)技术中的直连通信应用于自动驾驶场景的具体需求进行研究,给出不同业务场景下对通信性能和安全的需求说明。最后,针对车路协同系统低时延、高可靠和高并发的系统需求,分析5G NR V2X物理层、资源分配、拥塞控制和Qos与安全设计的相关原理。
文摘V2X(vehicle to everything)通信是车联网中实现环境感知、信息交互与协同控制的重要关键技术。大唐电信科技产业集团最早提出并由中国企业主导的LTE-V2X国际标准作为其中的主流技术之一,能够在高速移动环境中提供低时延、高可靠、高速率、安全的通信能力,并能够最大程度利用TD-LTE已部署网络及终端芯片平台等资源。首先介绍了LTE-V2X的关键技术,并与IEEE 802.11p进行了比较;进而介绍了LTE-V2X的标准研究及其演进以及相关的产业发展和示范应用;最后展望了LTE-V2X的发展策略及其向5G NR-V2X的技术演进等,并提出了相关政策建议。