Uhf Dipole Rfid Tag Antenna Design Method Research

Radio Frequency Identification (RFID) has great data capacity, long life, good environment adaptability,and is able to realize wireless identification within long-range or high-speed conditions.It has become a hot field of automatic identification research. As applications become clear and application fields expand, as a key component of the RFID system, antenna design and research has become very critical and urgent. Antenna technology is one of the key technologies in RFID system,and is significant to make the RFID technology mature and widely used in both theory and practice. Among all kinds of antennas, the tag antenna is directly related to the effect of the system,thus is drawing more and more attetion. Designers are trying to make the tag antenna minimized, work with low cost, high-performance and broad bandwidth.The thesis works on ultra-high frequency (UHF) RFID tag dipole antenna design. This paper analyzes and studies the specific needs of RFID tags, summarizes the challenges of antenna design, and proposes a general RFID antenna design process.Based on this process, the application of genetic algorithm optimization and the selection of control parameters and strategies is researched. In the process of derive the electromagnetic parameters of the antenna from the physical model of antenna, we introduces the numerical methods and discusses its application in electromagnetics.The we uses NEC which is a numerical computation tool based on the method of moments to caculate the performance of the antenna. The perfomance parameters are then used to obtain the individual fitness in the process of optimization using genetic algorithm. In practice, we applies the above findings to the UHF dipole tag antenna design process,and obtains two different UHF tag antennas to achieve the miniaturization of the antenna design and optimization, and validate the effectiveness of the method through simulation.This artical first reviews the RFID tag antenna design theory,explains the technical approach, and introduces the genetic algorithms and numerical methods for electromagnetic applications. Then we proposed the basic processes of RFID antenna design,researches the dipole antenna optimization techniques, and on this basis, focuses on a combination of genetic algorithms and numerical methods for antenna optimization. Finally, according to the different needs we designs two meander line dipole antenna, and validates the correctness with simulation results.