The Design And Implementation Of RSU In ETC Application

Intelligent Transport Systems (ITS) is a new transport management system under research and development in many countries. It combines Computer, Communication, Sensor, and Electronic technologies to manage and monitor transportation. To meet the particularity of ITS, Dedicated Short-Range Communication (DSRC) is introduced in. As a mainstream communication protocol dedicated to transportation system, DSRC defines two entities: On-Board Unit (OBU) and Road-Side Unit (RSU). It also defines some criteria to describe how OBU and RSU communicate, including the physical parameters, work flow and information structure.Nowadays, the primary application for DSRC is Electronic Toll Collection (ETC). In this scenario, RSU dominates the whole communication, and under the control of road side computer system, launches the transaction flow, completes a serial of operations from verifying the OBU device and vehicle, to fee calculating and tolling, and so on.After analyzing DSRC and ETC application, this paper proposes complete system architecture of RSU. Built on Linux, this architecture implements the simulation of Radio Frequency and HDLC module, and a set of detailed solution covering DSRC data link layer, application layer, device application layer and RSU's application interface as a two-stack gateway.This thesis first briefly introduces the ETC application and current research progress of DSRC protocol; the second chapter analyzes the Chinese standard's DSRC protocol and introduces the data link layer, application layer, device application layer separately; as the main chapter of this thesis, chapter three first presents the overall architecture of RSU, then introduces those basic service modules, and the detailed design and implementation of the three layers; the fourth chapter analyzes RSU's gateway role between DSRC protocol stack and TCP/IP protocol stack, and according to DSRC and ETC's characteristic, brings the design and implementation of three different application interfaces; finally the thesis gives out some conclusions and some problems that need further study.The design and implementation of data link layer and application layer in this paper and those application interface definitions can be easily transplanted.