Summary
International Symposium on Antennas and Propagation
2010
Session Number:3TB4
Session:
Number:3TB4-4
Impedance characteristics of an antenna apertured in metal housing wall of electronic equipment
Fukuro KOSHIJI, Kohji KOSHIJI,
pp.-
Publication Date:2010/11/23
Online ISSN:2188-5079
Summary:
In recent years, there are many cellular phones and laptop PCs using metal housing for strengthening and well-designing the housing. When an antenna is embedded in a wireless equipment with a metal housing, typically, an aperture on the housing at a location close to the internally mounted antenna is provided so that the housing will not affect impedance characteristics and not hinder the radiowave radiation. The aperture itself then is usually covered with a non-conductive material such as a plastic resin. However, it is difficult to ensure antenna characteristics over a wide frequency range by using this means. Especially in a UWB communication where a wide range of 3.1 GHz to 10.6 GHz is used, building an antenna for the UWB communication in a metal housing is a difficult task. Now, if it is possible to use the housing itself as an antenna, influences on an antenna characteristics, caused when an antenna and a metal housing are close each other, will disappear. And it provides an effective solution for small mobile electronic equipment being densely packed as a high-density packaging since it eliminates the need to place an antenna inside the housing. The authors have already proposed an antenna apertured with a half-semicircle and -trapezoid, formed in metal housing wall of a wireless equipment, and in case of equipment dimensions much larger compared with the UWB wavelength, we have confirmed to have the antenna characteristics enough for covering the UWB frequency band [1]. In this paper, the impedance, VSWR characteristics of the aperture antenna, formed in netbooksized and cellular phone-sized metal housing walls of 240 mm x 190 mm x 20 mm and 110 mm x 60 mm x 20 mm, respectively, as practical cases, were investigated.