Quad-band printed antenna for portable WLAN applications

Abstract

This paper presents a novel printed monopole antenna for quad-band operation in four WLAN bands: ISM 2.4 GHz, 5.2 GHz, 5.6 GHz, and ISM 5.8 GHz. This antenna is compact, thin, lightweight, easy to manufacture, and suitable for portable devices. It is composed of a folded strip radiator and two parasitic strips printed on a partially grounded substrate. The folded strip radiator interacts with the parasitic strips, which are connected to the ground plane, in such a way as to produce the resonant modes that originate the radiation bands of the antenna. An additional open-ended strip connected to the radiator is used to adjust the antenna input impedance in the upper operation band. A parametric study on several geometrical dimensions of the antenna is carried out in order to analyze their influence on the antenna performance. The fabricated prototype of the proposed printed monopole antenna has overall dimensions of 22 × 48 × 1.6 mm3, and the measured 10-dB return-loss bands exhibited by the antenna are 2149-2660 MHz and 5120-6035 MHz.