The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 12, 2013
Filed:
Jun. 10, 2011
Min-kao Hong, Taichung, TW;
Po-kuang Chang, Taoyuan County, TW;
Shang-sian You, Taichung, TW;
Industrial Technology Research Institute, Hsinchu, TW;
Abstract
A method for compensating the axial ratio of an antenna for testing radio-frequency identification (RFID) tags and an apparatus using the method are provided. The method includes the following steps. An initial location of the RFID tag (or a tagged product) is set to obtain an initial vector. The RFID tag and the antenna are respectively rotated with a first axis and a second axis to detect characteristics of the RFID tag in all directions, and the first axis and the second axis are perpendicular. A polarization angle of the RFID tag is calculated according to the initial vector of the RFID tag and a location of the RFID tag after rotation. A compensation value is obtained through a look up table according to the polarization angle, so as to compensate for the axial ratio of the antenna.