Dual-spiral slot antennas

Author

Hirose, K. ; Nakano, H.

Author_Institution

Coll. of Eng., Hosei Univ., Tokyo, Japan

Volume

138

Issue

1

fYear

1991

fDate

2/1/1991 12:00:00 AM

Firstpage

32

Lastpage

36

Abstract

Two types of dual-spiral slot antennas characterised by their simple feed are studied; one is a bidirectional radiation type (Bi-DSS) and the other is a unidirectional type (Uni-DSS). The radiation characteristics of the Bi-DSS are evaluated using the numerically determined magnetic current distribution. It is found that a travelling wave magnetic current distribution becomes dominant for a particular range of slot-arm lengths, contributing to the radiation of a circularly polarised wave. On the basis of the investigation of the Bi-DSS radiation mechanism, the Uni-DSS antenna with a triplate configuration is designed. Formation of a circularly polarised, unidirectional beam is experimentally realised. A 4*8 Uni-DSS array antenna with a simple feeding system is constructed, achieving an aperture efficiency of 60% over a frequency range of 11.6 GHz to 12.0 GHz.

Keywords

antenna radiation patterns; antenna theory; microwave antenna arrays; waveguide antennas; 11.6 to 12.0 GHz; SHF; aperture efficiency; array antenna; bidirectional radiation dual-spiral slot antenna; circularly polarised wave; numerical analysis; radiation characteristics; travelling wave magnetic current distribution; triplate configuration; unidirectional radiation dual-spiral slot antenna;

fLanguage

English

Journal_Title

Microwaves, Antennas and Propagation, IEE Proceedings H

Publisher

iet

ISSN

0950-107X

Type

jour

Filename

61685