The Design And Preparation Of HF/UHF RFID Tag Antenna

In the Internet of things, RFID tags have many advantages such as reading fast, easy to use and long service life. The tags are important components in the Internet of things. At present the traditional manufacturing technology of tags such as etching method and conductive ink printing method have complex process and the high cost of production which are the biggest obstacle to the application of RFID tags. The thesis explores a kind of printing electronic tags antenna manufacturing methods. This method has many advantages such as environment friendly and low cost. In this paper the main research content is as follows:1. Research and develop a kind of catalytic ink which can be used in inkjet printing and determined the components of the ink. The viscosity of the ink is 2.6 mPa·s, the surface tension of the ink is 33.5 mN/m and the optimum content of the catalytic particle is 0.3 mol/L. At the same time, the liquidity and stability of the ink is good.2. Surface modification of PI film was studied and the results showed that the potassium hydroxide and silane coupling agent can improve the surface roughness of PI film. They can improve the wettability of the substrate and enhance the bonding force between the substrate and metal layer. The surface roughness of modified PI film increases from 2.869 nm to 11.150 nm and the contact angle reduces from 40.9° to 22.9°. Determined the best components and concentration of the solution which including C4H4O6KNa·4H2O with the concentration of 24 g/L, EDTA·2Na with the concentration of 3 g/L, CuSO4·5H2O with the concentration of 11 g/L and HCHO with the concentration of 12 m L/L. And used the electroplate method to reduce the resistance of the coil. Test showed that the reading distance of the prepared HF tags can reach 2.5 cm, which satisfies the requirement of application.3. Designed a kind of antenna of UHF RFID tag which is simulation and optimization by using HFSS software. The resonance frequency of the antenna is 915 MHz. The return loss is-20.98 dB and the gain is 2.22 dB. The impedance of antenna is 7.2+126.9 j. In order to reduce the cost of antenna, the present paper proposed using paper as the substrate of antenna. And the surface treatment of paper has researched and developed. Determine the components and the best concentration of the solution by single factor variable method. The conductivity of the preparation of copper is 2.9×107 S/m, which showed that the copper layer had good electrical conductivity. Test showed that the reading distance of the prepared UHF tags can reach 42 cm, which satisfies the requirement of application.