Highly miniaturized dual band patch antenna

A highly miniaturized dual band patch antenna is proposed for small form factor (SFF) devices. The antenna is designed to resonate at two ISM bands; 2.4 and 5.2 GHz. The patch has a compact size of 8.8 by 10 mm2 which means a miniaturization of 74% is obtained that is considered high for dual band patch antennas. The miniaturization technique used is based on the combination of a shorting post and a defected ground structure (DGS). The antenna is an electrically small antenna (ESA) at 2.4 GHz. The dual band property is obtained by etching a U-slot in the ground layer as part of the DGS. Parametric studies are conducted to show how to control the antenna resonance for both bands. The antenna is fabricated on Rogers RO4350 board and the measured results have good agreement with simulated ones.