A compact triband ACS-fed monopole antenna employing inverted-L branches for WLAN/WiMAX applications

Abstract

A compact triband asymmetric coplanar strip (ACS)-fed monopole antenna for WLAN/WiMAX applications is proposed and investigated in this paper. The proposed antenna is composed of an ACS-fed folded monopole and two inverted-L branches, which occupies a very compact size of 26:5 × 12mm2 including the ground plane. By carefully adjusting the lengths and positions of these branches, three desired resonant frequencies can be achieved and adjusted independently. The antenna exhibits three resonances covering the 2.4/5.8 GHz WLAN bands and 3.5 GHz WiMAX band. Details of the antenna design, simulation, and experimental results are presented and discussed. The proposed antenna shows nearly omnidirectional radiation characteristics and moderate gains in the operating bands. The compactness, simple feeding technique and uniplanar design make it easy to be integrated within the portable device for wireless communication.