Double antennas for passive long range UHF-band RFID

Issue title: Selected Papers from the 15th International Symposium on Applied Electromagnetics and Mechanics (ISEM 2011)

Article type: Research Article

Authors: Watanabe, Kota^a | Watanabe, Yuta^{a; *} | Igarashi, Hajime^a | Waki, Hiroshi^b

Affiliations: [a] Hokkaido University, Sapporo, Japan | [b] East Japan Railway Company, Saitama, Japan

Correspondence: [*] Corresponding author: Kota Watanabe, Hokkaido University, 060-0814 Sapporo, Japan. Tel.: +81 11 706 6487; Fax: +81 11 706 7670; E-mail: watanabe@ssi.ist.hokudai.ac.jp

Abstract: This paper proposes double antennas which consist of receiver and backscatter antennas for passive long range UHF-band IC (Integrated Circuit) tags. The passive IC tags reply to reader's queries by using backscatter modulation. For this purpose, variable impedance elements are inserted between the antenna and a voltage multiplier which generate dc power. This decreases the efficiency of received power in the voltage multiplier and reduces the communication range. To solve this problem, we propose to use an independent antenna for backscatter modulation. Experimental results and numerical simulation results show that the double antennas successfully reply data from IC tag to the reader.

Keywords: Antenna, backscatter, FDTD, RFID

DOI: 10.3233/JAE-2012-1527

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 39, no. 1-4, pp. 671-676, 2012