A Smooth-Walled Feedhorn with Sub-30-dB Cross-Polarization Over a 30-Percent Bandwidth

The focus of this research was the design, optimization, and measurement of a monotonically profiled, smooth-walled scalar feedhorn with a diffraction-limited ~14° FWHM (full width at half maximum). It is an easier-to-manufacture, smooth-walled feed that approximates the properties of excellent beam symmetry, main beam efficiency, and cross-polar response over wide band-widths, but over a finite bandwidth.