Research On Reader For Multi-Chip Operating System Radio Frequency Smart Card

With the development of RFID(Radio Frequency Identification),contactless smart card has been applied for car-theftproofing, door-controlling,,non-stop-car-charging and so forth. However, most contactless smart card can only support single application, which limits the population. Likewise abroad and prevalent use complex the management and portability of card. To solve this problem, we put forward and design a multi-instruction system which integrates several different kinds of COS and applications in a single contactless smart card which is called RFID UCard . Because of the special architecture of the card,it can not interact with general RFID reader. So we have to design a RFID UCard reader coherently.According to research on the different using state of RFID UCard, we divide work mode of RFID UCard reader into management mode and user mode to achieve this object. On this basis, we design a communication protocol between reader and RFID Ucard based on the ISO/IEC 18000-7 protocol. Mainly, it adopts regularly interrupt to solve the time sequence controlling problem aroused from the broadening of changeable impulse in the protocol data link layer. Using slot ALOHA algorithm to solve the conflicts in the course of radio frequency communication.Aiming at the characteristics of the application environment of RFID UCard, we design a serial communication protocol and Ethernet communication protocol between reader and pc. Serial communication based on RS-232 protocol is designed for short distance communication; Ethernet communication which is comprised of ethernet interface chip and external components based on the IEEE 802.3 protocol is designed for long distance communications.At last, we design the frequency Ucard read-write machine with current chips, including microprocessor module, data memory module, program storage module, frequency module and network module; and analyze the dividing of memory, decoding circuit and etc.