Analysis of thin multioctave cavity-backed slot spiral antennas

Author

Ozdemir, T. ; Volakis, J.L. ; Nurnberger, M.W.

Author_Institution

Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI, USA

Volume

146

Issue

6

fYear

1999

fDate

12/1/1999 12:00:00 AM

Firstpage

447

Lastpage

454

Abstract

Thin cavity-backed Archimedean slot spirals are analysed through an efficient implementation of the finite element method. Through numerical analysis, fundamental differences between the free-space and cavity-backed configurations are identified. The bandwidth limitation imposed by the presence of the cavity is remedied by terminating the spiral slot with tapered resistive loading and employing larger apertures. Design improvements are presented based on the interpretation of the numerical simulations. It is shown that a 0.8 cm (0.33 in) thick and 24 cm (9 in) wide antenna can provide circular polarisation over a nearly 4:1 bandwidth

Keywords

UHF antennas; antenna radiation patterns; boundary integral equations; electromagnetic wave polarisation; finite element analysis; microwave antennas; slot antennas; spiral antennas; 0.33 in; 0.8 cm; 24 cm; 800 MHz to 3 GHz; 9 in; Archimedean slot spirals; SHF; UHF; bandwidth; bandwidth limitation; cavity; circular polarisation; finite element method; finite element-boundary integral method; free-space configuration; impedance matching; multioctave cavity-backed slot spiral antennas; numerical analysis; numerical simulations; radiation properties; tapered resistive loading; thin spiral antennas;

fLanguage

English

Journal_Title

Microwaves, Antennas and Propagation, IEE Proceedings

Publisher

iet

ISSN

1350-2417

Type

jour

DOI

10.1049/ip-map:19990429

Filename

817559