Design Of Reader Antenna For Radio Frequency Identification

In recent years,radio frequency identification(RFID),as an emerging wireless communication application,has been widely used in various applications such as logistics management,intelligent tracking,smart cards,animal tags,electronic tolls and store security.The reader antenna is an important component of RFID.The performance of the antenna will directly affect the efficiency and robustness of the whole system.This article is devoted to the research of miniaturized,broadband RFID reader antennas,which will work in the following aspects:First of all,this paper gives a brief introduction to the development of the reader antenna at home and abroad.The composition and basic theory of the RFID system,several structures and advantages and disadvantages of the micro strip antenna,basic parameters of the antenna and the feeding mode are introduced.The paper gives the research direction and work focus.Secondly,Aiming at the problems of large size and high design cost of current reader antenna,a miniaturized dual-band single-layer handheld reader antenna was designed for UHF and ISM bands.It was designed with FR4 dielectric layer.Firstly,a square slot was cut in the middle of the radiation patch,and a four-sided slot and a four-corner slot were separately cut on the radiation patch,which realized the dual-frequency and miniaturization of the antenna.Secondly,the parameters of the antenna structure were simulated and analyzed.Finally,the parameters of the antenna were determined,and the antenna was manufactured for testing.The test results show that the operating frequency band of the antenna are 910MHz-938MHz and 2.42GHz-2.48GHz,the impedance bandwidth are 28MHz and 60MHz,The maximum gain are-1.68 dB and-2.67 dB,so the antenna designed in this paper meets the requirements of UHF band and ISM band.The size of the antenna is 72 mm × 72 mm × 3 mm,which is smaller than other antennas of the same type.Moreover,the antenna adopts single-layer design,which reduces the design cost.At last,a novel compact dual-frequency reader antenna fed by coplanar waveguide is proposed.The size of antenna is 36 mm*30.5 mm*1.6 mm.The antenna resonates at 2.45 GHz and 5.8 GHz through“concave" poles and short poles.By loading semi-elliptical patches on the middle short pole,cutting triangular grooves on the grounding plates on both sides of the feeder and opening two L-grooves under the grounding plates,the antenna bandwidth has been widened many times.The impedance bandwidth of the antenna is 580MHz(2.18GHz-2.76GHz)and 1240MHz(4.89GHz-6.13GHz).The gain of the antenna is 2.43dB and 3.92dB at 2.45GHz and 5.8GHz.The antenna is fed by coplanar waveguide with simple structure and small size.It realizes dual-frequency and broadband,and has good practicabilityThe paper has 51 figures,7 tables and 67 references.