Title :
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
fDate :
12/1/1999 12:00:00 AM
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;
Journal_Title :
Microwaves, Antennas and Propagation, IEE Proceedings
DOI :
10.1049/ip-map:19990429
