CPW-fed circular slot antenna with slit back-patch for 2.4/5 GHz dual-band operation

Abstract

A circular slot antenna fed by a coplanar waveguide (CPW) is proposed for dual-band operations. Dual frequency bands that cover the 2.4 GHz (2400–2484 MHz) and 5 GHz (5150–5825 MHz) bands were obtained by embedding a pair of slits in the circular back-patch that is printed on the backside of the substrate and concentric with the circular slot. This design resulted in broadside far-field patterns with low cross-polarisation levels in both frequency bands and a small antenna size of 40×40 mm with the ground plane regarded as part of the antenna structure.