Compact dual-band printed monopole antenna for WLAN application

A microstrip-fed dual-band antenna with omnidirectional radiation patterns in the azimuth plane is proposed. It can provide two separate impedance bandwidths of 0.25 GHz (2.3-2.55 GHz) and 0.85 GHz (5.1-5.95 GHz), so that it easily covers the required bandwidths for wireless local area network applications. The proposed antenna is composed of a rectangular monopole and a folded strip whose end is coupled to the monopole by a narrow gap. It occupies an area of only 6.5 times 14 mm when printed on an FR4 substrate with a thickness of 1.5 mm.