%0 Electronic Article
%A U.R. Kraft
%K experimental results
%K thin-wire model
%K circular polarisation
%K polarisation properties
%K nonoptimised feed networks
%K resistively loaded arms
%K cavity backed spirals
%K small printed spiral antennas
%K compact antenna element
%K microstrip spiral
%K radiation pattern
%K crosspolarisation suppression
%K lumped resistive loading
%K gain reduction
%K printed four-arm spiral antenna
%X A small printed four-arm spiral antenna with lumped resistive loading is investigated to assess its suitability as a compact antenna element with pure circular polarisation. The results of numerical investigations based on a simplified thin-wire model are presented, which indicate XPD improvements of ≥ 14 dB in comparison to conventional spirals of the same size. The corresponding gain reductions are ~1 – 3 dB, which is at least equivalent to the performance of conventional cavity backed spirals. Furthermore, experimental results are discussed for a true microstrip spiral, which verify XPD improvements of 12 – 17 dB and show that XPD figures of 30 dB as well as a radiation pattern with acceptable symmetry can be obtained, even with simple nonoptimised feed networks. Areas for further improvements are identified and briefly discussed.
%@ 1350-2417
%T Polarisation properties of small printed spiral antennas with four resistively loaded arms
%B IEE Proceedings - Microwaves, Antennas and Propagation
%D April 1997
%V 144
%N 2
%P 131-135
%I
%U https://digital-library.theiet.org/;jsessionid=3ej6sto7pf6tl.x-iet-live-01content/journals/10.1049/ip-map_19971018
%G EN