Summary
International Symposium on Antennas and Propagation
2010
Session Number:4FA3
Session:
Number:4FA3-4
UWB Planar Antenna with Multi-slotted Ground Plane
M. Tariqul. Islam, Rezaul Azim, Norbahiah Misran, S.W.Cheung,
pp.-
Publication Date:2010/11/23
Online ISSN:2188-5079
Summary:
Broadband and multiband antennas play strong roles in the wireless communication world because of the increasing demand of high data transmitting rate. Due to the attractive characteristics such as low cost, low complexity, low spectral power density, high precision ranging, very low interferences and extremely high data rates, ultra-wideband (UWB) technology has recently been widely used in communication systems. As a key component of the UWB systems, the antennas with ultra-wide bandwidth have been widely investigated by many researchers since the Federal Communications Commission (FCC) has allocated 7.5 GHz spectrum from 3.1 to 10.6 GHz for UWB radio applications [1]. The design of an efficient and compact size antenna for recent wideband applications is still a major challenge. Many microstrip-fed and coplanar waveguide-fed antennas have been reported for UWB applications. These antennas use the monopole configuration such as circular ring, elliptical, annual ring, triangle, pentagon and hexagonal antennas; the dipole configuration like bow-tie antennas [2-9]. Some of reported UWB antennas do not have a planar structure due to their ground planes perpendicular to the radiators and they are not suitable to be integrated with the printed circuit boards. There are numerous and well-known methods to increase the bandwidth of UWB antennas, including increase of substrate thickness, use of a substrate with low dielectric constant, employment of various feeding techniques and the use of slot antenna geometry[10,11]. However, the bandwidth and the size of an antenna are generally mutually conflicting properties; improvement of one characteristic normally results in degradation of the other. Recently, to increase the impedance bandwidth in circular and elliptical planar monopole antennas, techniques such as the insertion of additional stub to the one side of the circular patch [12], increasing the elliptically ratio of ellipse-shaped patch [4], addition of the slot on one side of the radiating element [13] and adding steps to the lower edge of the patch [14] have been reported. The square shaped antenna fed by a microstrip line, which has the planar configuration, is a good candidate in wideband applications. In this paper, a wideband antenna that achieves a physically compact planar profile, sufficient impedance bandwidth and bi-directional radiation pattern is proposed. The proposed planar antenna consists of a square shaped radiating patch and partial ground plane with rectangular slots on its upper side to cause a wide bandwidth from 2 to 17 GHz for UWB applications.