Design of Multiband Balanced Folded Dipole Antenna Based on a Dual-arm Structure for Mobile Handsets

Abstract

In this paper, a balanced antenna for mobile handset applications with enhanced bandwidth performance, that covers four bands (GSM1800, GSM1900, UMTS and 2.4-GHz WLAN), is investigated. The antenna is a slot planar dipole with folded structure and a dual-arm on each monopole. A wide bandwidth planar balun is employed to feed the wideband balanced antenna from an unbalanced source. A prototype of the proposed antenna is fabricated and tested. The performance of the antenna is verified and characterized in terms of return loss, radiation patterns and power gain. The calculated and measured results show good agreement and also confirm good wideband characteristics for the proposed antenna with multiband operation.