系统及DSRC协议的分析与实现.docVIP

摘要 随着高速公路的建设和车流量不断地增长，原有人工收费站的通行能力已经难以满足车辆快速通行的要求，而采用电子不停车收费系统(Electronic Toll Collection，简称ETC)可以有效地解决这一问题，本文在对ETC系统的分析基础上，重点研究DSRC通信协议的设计与实现。 ETC系统包括两部分：路侧单元(Road-Side Units，简称On board Unit，简称OBU)。RSU通过专用短程通信协议(Dedicated Short Range Communication，简称DSRC)与OBU实现通信和数据交互，完成交易过程。DSRC协议是专用于智能交通领域的一种短距离无线通信协议，协议分为三层：物理层、数据链路层、应用层。国内的DSRC协议是基于5.8GHz频段的。它是车载单元(OBU)与路侧单元(RSU)进行单向或双向交互式通信的标准，将车辆和道路有机地连接起来。从而，交通控制中心可以通过与行驶车辆的数据通信实现对车辆的智能管理，同时车辆还能够接入交通信息网，使用信息网中的资源。本文首先分析了ETC系统关键词：ETC系统DSRC)；路侧单元(RSU)和车载单元(OBU)；媒介访问控制子层(MAC)；逻辑链路控制子层(LLC) Abstract With the constant increasing of highway construction and traffic, the existing manual traffic capacity of the toll station could not meet the requirements of the speedy passage of vehicles. Using Electronic Toll Collection(ETC) can effectively solve this problem. In this paper, we focus on the design and implement of DSRC protocal data link layer based on the analysis of ETC system. The ETC system includes two parts: one of them is road side unit(RSU), and the other is on board equipment(OBU). The RSU communicate with the OBU using DSRC protocal(the dedicated short range communication) completing bargain process． The DSRC protocal is a kind of short range wireless communication protocols, which is applied exclusively in the intelligence transportation field. It defines three layers: physical layer,data linker layer,and application Iayer. The inland DSRC protocal is based on the frequency of 5.8GHz. It is a standard of interactive communication in the single or double directions between on board equipment(OBU) and road side unit(RSU). And with the help of this protocol, the roadside and vehicle unit are connected perfectly together. Thereby the transportation control center can manage the vehicle with the communication data of the driving vehicle. At the same time. the vehicle can connect into the transportation information network and use the information resources in the network. Firstly, this thesis introduce the ETC system, and in