許博文臺灣大學：電信工程學研究所劉昱緯Liu, Yu-WeiYu-WeiLiu2007-11-272018-07-052007-11-272018-07-052006http://ntur.lib.ntu.edu.tw//handle/246246/58537這篇論文分析了在射頻認證(RFID)系統裡阻抗匹配的細節。而 射頻認證系統主要包含了有閱讀機和標籤，其中的標籤是由積體電路 晶片和天線所組成。不管是晶片或天線，他們都有複數的阻抗。為了 達到最大的功率轉換，晶片和天線在輸入阻抗上必須達到共軛匹配。 本文提出了一款天線，它不只可以調整輸入阻抗的實部，也可以 調整輸入阻抗的虛部。而且它可以達到其他在射頻認證系統上的要 求，比如小巧的尺寸和全方位的場型。 為了量測天線的數據，本文提出了另一款的天線，它可以直接被 量測而且和原來天線的形狀也很類似。同時論文裡也比較了他們的差 異，而差異只有一點點。所以作者可以確定原來的天線確實可應用在 射頻認證系統裡。This thesis analyzes impedance matching concepts in passive radio frequency identification (RFID) system, which is including a reader and a tag. The tag is consist of an integrated circuit chip and an antenna, both with complex impedances. For maximum power translation, the chip and the antenna must be conjugate matching in input impedances. This thesis proposes an antenna, which not only the real part but also the imaginary part of the input impedance can both be tuned. Also, the antenna can meet other RFID antenna requirements, such as the compact size and the omnidirectional pattern. For measuring the characteristics of the antenna, we propose another antenna, which can be directly measured and is analogous to the original one, and compares differences with the original one. Their differences are small, so it can be certain that the original design is suitable for RFID applications.Contents Chapter 1. Introduction………………………………………1 1.1 Motivation……………………………………………………………………1 1.2 Chapter Outlines……………………………………………………………...6 Chapter 2. Loop Antenna Theory.……………………………7 2.1 The Small Current Loop…………..………………………………………….7 2.2 Traveling Wave Current on a Loop…………………………………………11 2.3 Coplanar Strip Transmission Line…………………………………………..14 Chapter 3 RFID Antenna……………….…………………...17 3.1 RFID Antenna Requirements……………………………………………….17 3.2 Behavioral Modeling of RFID Antenna…………………………………….21 3.3 Read Range…………………………………………………………………25 Chapter 4 CPS-fed RFID Antenna………………………….29 4.1 Geometry…………………………………………………………………....31 4.2 Test Geometry………………………………………………………………37 Chapter 5 Conclusions……..………………………………...49 Appendix A TRL Calibration……….…...…………..……...51 Reference…………….……………………………………….551147815 bytesapplication/pdfen-US無線射頻認證天線RFIDantenna無線射頻認證應用之共面帶線饋入矩形環狀天線Coplanar Strip Fed Rectangular Loop Antenna for Radio Frequency Identification Applicationsthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/58537/1/ntu-95-R93942061-1.pdf