The Design Of RFID Reader Based On UHF

With the wide application of computers, the automatic identification technology plays more and more important roles in kinds of areas. The bar code technology which is such one of the automatic identification technology is still adopted widely in many fields because of its low price. However, with the quick development of the science and the technology, the bar code technology can't meet the high demands of the information for the defect of small-storage and poor security. The RFID electronic tags emerge as the time requires and will replace it in future. As a high-tech product which combines many technologies such as semiconductor technology, high-frequency technology, electromagnetic technology, data encryption technology and so on, RFID electronic tags technology becomes more and more important in national economy and it will accelerate the process of modernization in China.In my research, I focus on the design of a RFID interrogator. A method of complete several separated IC is adopted in my design which replaces ASIC for UHF RFID. Instead of using the method of the popular quadrature modulation, I adopt the lower cost controllable gain amplifier (VGA) chip for modulation after analyzing the requirements of modulation parameters in protocol, and we get the satisfied results. The waveforms from chip accord with the protocol requirements totally and they are able to be identified by the electronic tags. In a word, this design can achieve the communications with electronic tags as well as meeting the requirement of low cost.In this paper, I give the detail introduction including of protocol analysis, election of chips, design methods both in software and hardware and the whole system design. Besides, I also give the theoretical support in some noteworthy parts of the design.