Dedicated Short Range Communication National Standards For Electronic Toll Collection On The Obu

Traffic pressure increases as the development of road traffic in recent years. The system of Electronic Toll Collection (ETC) which can significantly short charge time has become one of the most effective programmes to solve this problem.Chinese government has announced national standards named Electronic Toll Collection-Dedicated Short Range Communication. It can regulate the design and also can increase system compatibility. This paper, construes the national standards of ETC, then compares to the DSRC (Dedicated Short Range Communication) protocol of Europe which has been used before in our country.Based on the analysis of stamdards, OBU (On Board Unit) has been designed in this paper which follows the national standards. OBU, as a part of ETC system is installed inside the vehicle. In hardware, SCM (Single-Chip Microcomputer) VRS51L3074 of RAMTRON has been used. In software, it creates frame according to the national standards in order to implement the main functions of data link layer. It also completes the operation of receiving and sending frame at the OBU portion by dominating periphery circuitry. Besides, it controls OBU to conduct various acts in accordance with RSU (Road Side Unit). In this paper, high-speed serial which required meeting national satandards has been tested. MIFARE 1 IC card and highly integrated reader MF RC500 are used to implement dual-chip electronic tags in this design. At last, power supply manager has been designed to solve the problem of power loss. TI's MSP430 MCU has been used. It manages power supply on OBU to save power and exteneds the battery life.