Tri-band monopole antenna with rectangular ring resonator for GSM 1800/1900, WLAN and WiMAX applications

A tri-band antenna for GSM, WLAN and WiMAX applications has been presented in this paper. Overall size of the proposed antenna is 45 × 85 × 0.8 mm
³
. It is fabricated on FR4 epoxy substrate. This paper discusses the overall evolution of the design and also discusses simulated and measured results. The effects of rectangular ring resonator, symmetric parasitic element and rectangular slots have been presented. The proposed antenna has resonant frequencies at 1.8 GHz, 3.6 GHz and 5.05 GHz with impedance bandwidth of 40%, 20.8% and 5% respectively. The peak gain of the proposed antenna is 4.6 dBi at 3.7 GHz. Parametric variation has been employed to optimise the results and polynomial regression equation has been presented relating a design parameter with first resonant frequency. The results were simulated using Ansys HFSS.