Wideband (5-6 GHz WLAN band) circularly polarized patch antenna for wireless power sensors

A small wideband microstrip patch antenna is introduced. The antenna is designed to function in the 5-6 GHz wireless LAN bands. It achieves multi-band functionality through the addition of two slots to a square patch (21 mm by 21 mm by 2.5 mm). The proposed antenna also generates circular polarization and has a 3 dB axial ratio bandwidth of 2.8%. The impedance bandwidth of the antenna is more than 14% within 2:1 VSWR.