A Compact CPW-FED Omni-Directional Monopole Antenna for WLAN and RFID Applications

A compact dual-band CPW-fed triangle-shaped antenna is proposed for applications in 2.4/5 GHz WLAN and RFID. The designed antenna, including ground plane, is only 28 mm in height and 26 mm in width. By introducing a Π-shaped slot and a T-shaped strip, the proposed antenna can generate two separate impedance bandwidths. Prototypes of the proposed antenna have been constructed and tested. The measured impedance bandwidths, ranging from 2.36 GHz to 2.50 GHz and from 5.01 GHz to 6.33 GHz separately, are obtained with return loss less than -10.00 dB, which meet the required bandwidths specification of WLAN and RFID. Good omni-directional radiation and appropriate gain characteristics in the desired frequency bands have been achieved.