The Research Of RFID Reader And Antennas

As an automatic identification technique without touching, radio-frequency identification (RPID) technology use radio waves carrying information stored about the identified object or commands to identify objects via space coupling, such as inductive coupling or electromagnetic wave propagation. Compared with other identification technologies, RFID technology used for identification has many advantages. The prominent characteristics of RFID make it have dual significance of theory and actuality on research and development.This paper start with a detailed introduction of RFID systems, as well as the prospects for development of applications, thus the introduction of RFID antenna technology, one of the key technologies in RFID systems is brought in. First, a general design method of a monopole RFID reader antenna at 2.45GHz is given. Then, based on the microstrip antenna research, a dual-band stacked two-layered microstrip patch RFID reader antenna which resonates at 900MHz and 2.4GHz. Then electromagnetic simulation is processed by using HFSS, and meanwhile the impact of the key dimensions for the antennas to the performance are summarized. Finally, the structural dimensions meeting with requirements is achieved, and the RFID reader antenna prototype is fabricated, comparing the measurement results and simulation results in order to validate the accuracy of HFSS.Meanwhile, an active RFID reader module working at 2.45GHz microwave frequency band is proposed. The radio frequency part is composed of nRF2401 radio frequency chip and MSP430 MCU, and the SP3223 chip is used as the main chip of the base-band part to achieve communication between the reader and the serial RS232 of computer.In addition, the paper also relates to the basis parameters introduction of antenna as well as the description of antenna measurement.The work was supported by "research on RFID tag antenna design technology" of National High Technology Research plan (863 plan).