附著於高導電性物體之RFID晶片天線設計

Design of the RFID Tag Antenna Attached on the High Conductivity Object

王肇頡(Chao-Chieh Wang)

指導教授 ： 林丁丙 ； 李慶烈 ； 湯譯增

國立臺北科技大學/電資學院/電腦與通訊研究所/碩士(2011年)

摘要

本論文目的為設計創新的天線結構，應用於超高頻RFID晶片之台灣RFID頻段接收(922 MHz~928 MHz)的微型化天線，可附著至高導電性材料上，克服一般RFID晶片於高導電性物體可讀性過低的問題。
本文針對台灣頻段RFID系統，提出兩種縮小化天線結構，第一隻天線主要是利用微帶天線來做設計，利用晶片連接微帶線饋入，選擇饋入微帶線位置激發天線模態，達到台灣RFID頻段接收，並且利用天線二分之一波長空腔諧振的特性結合短路傳輸線的結構達到與晶片共軛匹配的效果，天線尺寸為66 × 13 mm2。
第二之天線主要是利用迴路天線與指叉式電容耦合的架構，將兩個四分之一波長的路徑容納於同一個天線平面中，達到縮小化設計方式，並探討指叉電容的手指數及U型迴路的長度對於天線阻抗特性之影響，使得此天線可達到台灣RFID頻段操作，天線主要輻射體的部分為33.5 × 18.5 mm2。經由模擬驗證及實際製作量測，兩天線附著於高導電性物體具有高可讀性，且能完整操作於台灣RFID頻帶範圍。

關鍵字

微帶天線 ； 迴路天線 ； 指叉式耦合

並列摘要

The purpose of this paper is design of innovative antenna structure, Application for RFID tag in Ultra high frequency of Taiwan RFID band(922 MHz ~ 928 MHz) miniaturized antenna, can attach on high conductivity object, to overcome the general low readability problem of RFID tag antenna, the proposed antenna can be used to any printed circuit board. In this paper proposed two kind of miniaturized antenna of Taiwan RFID band.
A printed antenna using patch structures on system ground for RFID reception in the Taiwan UHF band is proposed in this paper. By utilizing the micro-strip connecting to the tag, to select the feed position achieve the antenna mode, and use the half-wavelength and shorting transmission line structure to conjugate matching the RFID tag. Antenna has a compact size of 60×13mm2.
The second proposed antenna has a simple loop structure comprising the interdigital capacitor coupling, two quarter-wavelength path accommodate in the same antenna plane, to miniaturized antenna design, and to discuss the antenna impedance characteristics with the number of interdigital capacitor's finger and U-loop length, to achieve the antenna can operate in Taiwan RFID bands, the antenna main radiation part has a compact size of 33.5×18.5mm2. Produced by the simulations and actual measurements, two antennas attached to the object of high conductivity with high readability, and can complete operations in Taiwan RFID frequency band.

並列關鍵字

patch antenna ； loop antenna ； interdigital coupling feed .

參考文獻

[1] G. Marrocco, “The art of UHF RFID antenna design : impedance-matching and size-reduction techniques,” IEEE Antennas and Propagation Magazine, vol. 50, no. 1, pp. 66 - 79, Feb. 2008.

[2] K. V. S. Rao, P. V. Nikitin, and S. F. Lam, “Antenna design for UHF RFID tags: A review and a practical application,” IEEE Trans. Antenna Propag., vol. 53, no. 12, pp. 3870 - 3876, Dec. 2005.

[3] P. V. Nikitin, K. V. S. Rao, S. F. Lam, V. Pillai, R. Martinez, H. Heinrich, “Power reflection coefficient analysis for complex impedances in RFID tag design,” IEEE Trans. Microw. Theory and Tech., vol. 53, pp. 2721-2725, Apr. 2005.

[5] H. W. Son, C. S. Pyo, “Design of RFID tag antennas using an inductively coupled feed ,” Electron. Lett., vol. 41 , pp. 994-996, Sep. 2005.

[6] J. Ahn, H. Jang, H. Moon, J. -W. Lee, and B. Lee, “Inductively Coupled Compact RFID Tag Antenna at 910 MHz With Near-Isotropic Radar Cross-Section (RCS) Patterns,” IEEE Antenna Wireless Propag. Lett., vol. 6, pp. 518-520, 2007.