Broad-Band Matching of Antennas using Dual-Mode Radiators

Author

Hunter, Ian

Author_Institution

Institute of Microwaves and Photonics, School of Electronic and Electrical Engineering, University of Leeds, Leeds LS29JT, UK, Tel [+44](0)113 3432055, Fax [+44](0)113 3432032, e-mail: I.C.Hunter@ee.leeds.ac.uk

fYear

2003

fDate

Oct. 2003

Firstpage

431

Lastpage

434

Abstract

This paper describes a new method for increasing the bandwidth of microwave antennas. This is achieved by recognizing that microstrip patch antennas may support two orthogonal resonant modes, or polarizations. These resonant modes may be modelled by a simple filter network, consisting of two coupled resonators, which represents the input impedance of such a dual-mode antenna. A novel and simple method of maximizing the bandwidth of the input reflection coefficient of a dual-mode antenna, by suitable choice of resonator couplings is presented. This method provides a theoretical bandwidth improvement of more than 300% when compared with a single mode antenna. The result is experimentally confirmed. From a practical point of view the method could have useful application in the design of antennas for mobile phones.

Keywords

Bandwidth; Impedance; Microstrip antennas; Microwave antennas; Microwave filters; Microwave theory and techniques; Patch antennas; Polarization; Resonance; Resonator filters;

fLanguage

English

Publisher

ieee

Conference_Titel

Microwave Conference, 2003 33rd European

Conference_Location

Munich, Germany

Print_ISBN

1-58053-834-7

Type

conf

DOI

10.1109/EUMA.2003.340982

Filename

4143046