Summary
International Symposium on Antennas and Propagation
2010
Session Number:2WB1
Session:
Number:2WB1-1
A New Broadband Trapezoidal Flat Monopole Antenna
Behrouz Heydari, Alireza Islamdoost,
pp.-
Publication Date:2010/11/23
Online ISSN:2188-5079
Summary:
Before getting through the structure of the antenna in this article, first we consider the process of changes in flat monopole antenna. The first flat monopole antenna was proposed by Mr.B.J. Lamberty in 1958 Fig. 1. After that, from 1992 till now, other shapes of that antenna have been introduced that you can see in Fig. 2, 3and4. [1]The reason of using a flat instead of a bar in monopole antennas is to increase the bandwidth [2] though all of the mentioned antennas have some advantages and disadvantages. For example, in circular flat antenna, increasing frequency, the radiation pattern of the antenna will worsen the condition, although it has a greater wideband (about 10:1). In designing the circular flat antenna which its working limitation has defined between 2.25 to 17.25 GHz, the result is VSWR< 2, but the maximum radiation of antenna in E-plane with frequency changes from 2.5 to 9 GHz varies from 30° to 60° or in H-plane we have some changes in radiation pattern from 4 dB to 7 dB. [1], [3] Although elliptical flat antenna has a better condition than circular flat which was proposed in 1998, tried to decrease the mentioned defects, but the problem of changes in the title of pattern angle in E-plane has remained as well. [1], [4] In trapezoidal flat antenna which was proposed in 1999, tried to decrease the mentioned defects, but the problem of changes in the title of pattern angle in E-plane remained as well. [1], [5] With these explanations we get through the configuration of the mentioned antenna.