Summary
International Symposium on Antennas and Propagation
2012
Session Number:POS2
Session:
Number:POS2-58
Wireless Pads for RFID Reader
Takuya Okura, Hiroyuki Arai,
pp.-
Publication Date:2012/10/29
Online ISSN:2188-5079
Summary:
To extend the RFID applications, the frequency band of UHF (900 MHz) and 2.45 GHz band are recently used for long range and high data rate transmission. A medium range distance applications need to detect RFID in wide area without reading errors. Free access mat has been proposed as the reader with high transmission efficiency, however its double layered structure is not easy for mass production process. This paper presents two type of one layer wireless pad using microstrip structure. First, we propose a wireless pad using a microstrip filter geometry. To decrease its polarization dependence loss, we change the geometry of filter arrangement and receiving antenna structure. As a result, the average received power level in each direction becomes uniform, and its deviation is about �}6 dB. Next, we propose circularly polarized feeding antennas for RFID antennas with a freedom of its orientation and polarization and optimize this structure. As a result, the average value of the received power is almost uniform, and the deviation is about 16.6 dB.