International Publisher for Advanced Scientific Journals (IPASJ)
Miniaturization is the development trend of RFID (Radio Frequency IDentification) reader antenna. A miniaturized design of a CP (Circularly Polarized) antenna for UHF (Ultra-High Frequency) RFID reader is given in this paper. In order to compact antenna, four T-shape slots that can lengthen the path of surface current so as to drop the operating frequency, are etched on the square radiating patch. To realize CP property, the patch is truncated by a square of 6.5 mmx6.5 mm at two diagonal corners.