An ACS-fed F-shaped monopole antenna for GPS/WLAN/WiMAX applications

Abstract

In this paper, an asymmetric coplanar strip (ACS)-fed quad-band monopole antenna for the global positioning system (GPS), wireless local area network (WLAN), and worldwide interoperability for microwave access (WiMAX) applications is proposed. It is composed of an F-shaped monopole and a partial ground plane, which are both printed on one side of a low-cost FR4 substrate with a compact volume of 40 × 20 × 1.6 mm3. By cutting an open-ended Γ-shaped slot into the F-shaped monopole, four distinct resonant modes are successfully generated. The design process, especially the geometrical configuration of the critical Γ-shaped slot is studied in detail. The proposed antenna has been fabricated and experimental results show that the −10 dB impedance bandwidth can fully cover the 1.575-GHz GPS (1.57–1.59 GHz), 2.4/5.2/5.8-GHz WLAN (2.4–2.485, 5.15–5.35, and 5.725–5.825 GHz), and 2.5/3.5/5.5-GHz WiMAX (2.50–2.69, 3.30–3.70, and 5.25–5.85 GHz) applications with nearly omni-directional radiation patterns and satisfactory gains.