基于网络编码的车辆间数据分发研究

发布时间：2018-03-30 03:18

本文选题：车载自组织网　切入点：网络编码　出处：《南京邮电大学》2014年硕士论文

【摘要】：目前随着车载自组织网和物联网的发展和标准的不断完善，人们除了应用车载自组织网解决行车交通安全外，对于车载数据信息服务的商业开发越来越感兴趣。当前的智能交通系统主要基于已经广泛应用的2G/3G网络或应用于车辆间的车辆专用短距离通信（DSRC，Dedicated Short Range Communications）为车辆数据信息服务。而这两种通信方式都有其局限性：对于3G网络而言，其在高速运动状态下数据传输速度并不理想且服务价格昂贵（下载大型文件数据）；而专门针对高速移动的车载环境通信的DSRC与路边接入点通信下载数据信息，数据传输速度很快，但受限于路边接入点的覆盖范围有限和初始阶段接入点布置数量有限的问题，导致网络连接总是时断时续。无法保证持续高质量的网络连接。为了克服以上车载自组织网中分发常用内容（是指那些大多数车辆下载都感兴趣的常用的商业服务类应用的大型多媒体文件内容）遇到的困难，车辆间合作下载的方式应运而生。首先，本文改进了车辆间合作下载模型，将网络编码方法应用到数据分发过程。道路上位置临近的车辆形成车辆簇，簇内车辆相互合作下载，同时利用了广覆盖的移动2G/3G网络作为控制信道，簇内车辆通过路边接入点进行车与路边基础设施通信（V2I，Vehicle-to-Infrastructure）通信的高数据下载率，提高了车辆的平均下载速率缩短了下载时间。其次，本文主要关注V2I分组数据分发过程，将网络编码方法应用到该数据分发过程中，与传统的基于随机和基于反馈方法两种V2I数据分发方法相比减少了数据间的重复冗余，并且不需要上传分组目录信息网络开销小。最后，对这3种方法分别进行了数学推导，，计算出了各自完成下载所需的平均时间。通过数学分析及仿真验证说明，相比于基于随机和反馈方式，基于网络编码的数据分发方法效率最高且网络开销最小。
[Abstract]:At present, with the development of vehicle-borne ad hoc networks and Internet of things and the continuous improvement of standards, in addition to the application of vehicular ad hoc networks to solve traffic safety, There is growing interest in the commercial development of onboard data and information services. The current intelligent transportation system is based mainly on the already widely used 2G/3G network or dedicated short-range communication between vehicles (DSRC / dedicated Short Range communications) as the number of vehicles. According to information services. And both of these communication methods have their limitations: for 3G networks, The data transmission speed is not ideal and the service price is expensive under the condition of high speed motion (download large file data), while DSRC, which is dedicated to the high-speed mobile vehicular environment communication, communicates with the roadside access point to download the data information. The speed of data transmission is fast, but limited by the limited coverage of roadside access points and the limited number of access points in the initial phase. Results in a network connection that is always intermittent. There is no guarantee of continued high quality network connectivity. To overcome the distribution of common content in the above vehicular ad hoc networks (that is, those commonly used business clothes that are of interest to most vehicle downloads). The difficulties encountered by large multimedia file content in service applications, The mode of collaborative downloading between vehicles came into being. Firstly, the cooperative download model between vehicles is improved, and the network coding method is applied to the data distribution process. The vehicles near the road form a vehicle cluster, and the vehicles in the cluster cooperate to download each other. At the same time, using the widely covered mobile 2G/3G network as the control channel, the vehicles in the cluster can communicate with the roadside infrastructure through the roadside access point with high data download rate, which improves the average download rate of the vehicle and shortens the download time. Secondly, this paper mainly focuses on the V2I packet data distribution process, and applies the network coding method to the data distribution process. Compared with the traditional V2I data distribution methods based on random and feedback methods, it reduces the duplication of data. And no need to upload packet directory information network overhead. Finally, the mathematical derivation of the three methods is given, and the average time required to complete each download is calculated. The results of mathematical analysis and simulation show that, compared with the methods based on randomness and feedback, The data distribution method based on network coding has the highest efficiency and minimal network overhead.
【学位授予单位】：南京邮电大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U495;TP391.44;TN929.5

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