The Study And Design Of UHF RFID Reader

Radio Frequency Identification (RFID) is a non-touched automotive identification technique realized by radio frequency communication. The technique utilized Integrated Circuit(IC), Electromagnetic field theory, radio transceiver, and data encoding and decoding, as well as many other techniques. The system is not limited to line of sight(LOS) operating environment. Because of long identification distance, high speed data transmission rate, counter-fabrication, and intelligence, it is widely used by all kinds of fields.In recent years, RFID has penetrated to more and more fields. Especially, RFID in 915MHz has better performances than RFID in13.56MHz, such as long reading and writing distance, high reading-writing rate. What's more, the collision avoidance technique can be used to identify multi-object. It is widely used in storage and logistics, and non-stop tolling.In the paper, firstly, the fundamental concepts, working principals and some specifications of RFID system are introduced. Secondly, circuit scheme of RFID reader are proposed. In this scheme, AT91SAM7S256 from ATMEL is used as the main controlling chip. The newest chip R1000 from INTEL is working as the radio transceiver module. The MAAP-007649-000100 from MA/COM is chosen as the power amplifier in the system. RFID reader antenna is implemented in microstrip. Ansoft EM simulation HFSS is used as a tool for simulating and optimizing the antenna performance. According to the optimized result given in the HFSS , a microstrip antenna is tailored and tested. Based on hardware configuration, bottom communication software is programmed using Visual C++, Using Visual Basic software for checking on work attendance is programmed. At last a system for checking work attendance based on RFID architecture is realized.The UHF RFID reader in the thesis is in conformance with protocol requirements, such as ISO 18000-6C, EPC Global Class1 Gen2. It has characteristics of high reliability and modularization. The reader can get to 640kbps uplink. Demands in the practical usage can be met.