Recent requirements for wideband dual polarized antennas with good pattern circular symmetry have centered on two feed candidates cavity backed Modulated Ann Width MAW spiral and Sinuous antennas. Both of these antennas are capable of arbitrarily wide bandwidth operation practical bandwidths are limited by photo-etching and feedpoint considerations. The properties of these antennas appear not to be widely known and to date the useful range of design parameters have not been published. This paper will show and compare the properties of two corresponding models of the multi-arm MAW spiral and Sinuous antennas. The feeds will be compared for the four-ann case which yields dual circular polarization or orthogonal linear operation as well as six-arm versions which can provide both sum and difference mode operation.
This article is from 'Proceedings of the Antenna Applications Symposium Held on 25-27 September 1991. Volume 1, ADA253682, p434-454.