Compact circularly polarized RFID tag antenna with an embedded U-shaped feedline for metallic surfaces

• A passive radio frequency identification (RFID) tag antenna with circular polarization (CP) radiation is proposed to operate at 902-928MHz and mount on metallic surfaces. A U-shaped terminal short-circuited feedline welded to a tag-chip is embedded in a rectangular slot to achieve a coupled feeding and a good impedance matching. By employing two truncated corners and two L-shaped slots with unequal length on the patch, a good left-hand circular polarization (LHCP) and compact size are obtained. The measured impedance bandwidth of the antenna is 85MHz (875-960 MHz), while the simulated 3-dB CP bandwidth is 6MHz (912-918 MHz). The proposed tag antenna shows reasonable read ranges when mounted on the metal plate in the following experiment.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering (hsv//eng)

Keyword

Bandwidth

Circular polarization

Electric impedance

Metallic compounds

Mobile antennas

Plate metal

Polarization

Radio frequency identification (RFID)

Surface measurement

Circularly polarized

Coupled feeding

Left-hand circular polarizations

Measured impedance

Metallic surface

Radio-frequency-identification tags (RFID)

Rectangular slots

RFID tag antennas

Antenna feeders

Publication and Content Type

ref (subject category)

kon (subject category)