Broadband planar antenna with improved pattern bandwidth

Abstract

This article presents the design of an inverted planar F antenna that uses a geometry in which the upper (radiating), short, ground and capacitive excitation plates are divided into two parts. By means of this geometry and the capacitive excitation technique, it is possible to achieve diagram and impedance bandwidths close to 52.44% (1.66 GHz to 2.84 GHz) and 8% (3036 GHz to 3.64 GHz) for a VSWR <= 2.0 The results measured for these parameters are higher than those obtained by the traditional direct terminal excitation technique or other capacitive excitation methods used in inverted F flat antennas (PIFA). The prototype built allows the simultaneous operation of the antenna in the bands of DCS 1800, DCS 1900 UMTS, WiFi, 2.4 GHz, WiMAX (2.3 GHz to 2.5GHz) and (3.4GHz to 3.5GHz) and in the band assigned for the standard (Bluetooth). The radiation patterns obtained within these bandwidths are reasonably omni-directional.

Keywords

• PIFA antenna
• wideband antenna
• capacitive feed technique