用于射频识别系统的抗电磁干扰抑制材料研究.pdfVIP

Abstract The aim of this dissertation was to provide theoretical and experimental evidence for anti-EMI suppression material used for radio frequency identification system (RFID). Aimed at the problem of tag can’t used to metallic environment in RFID system, the reason was analyzed. The practicable plan will be given base on measure method and preparation method. At first, according to the theory of electromagnetism, transmission-line and antenna, the reason which tag can’t used to metallic environment in RFID system was analyzed, and determined the corresponding countermeasure.On the basis of deducing impedance calculation, the measuring principle of the relative complex permeability was analyzed. The reason which tag can’t use to metallic environment in RFID system is electromagnetic induction changed the electromagnetic field distribution around tag and indirectly changed input impedance of the tag antenna.On the basis of deducing impedance calculation, “One circle inductance” physical model on magnetic ring samples was perfected. Secondly, suppression material is prepared in order to solve problem which tag should not apply to metal in the environment.With the combination of theoretical analysis and foreign suppression material analysis, design appropriate process of anti-EMI suppression material used for RFID system.Suppression material was successfully prepared through the reasonable process which flattened alloy powder after the vacuum annealing mixed organic compound and pressed into suppression material.Using X-ray diffraction、 scanning electron micr