Waveguide fed broadband millimeter wave short backfire antenna

A broadband millimeter (mm)-wave short backfire antenna (SBA), excited by a bowtie dipole and fed by an E-band rectangular waveguide, is presented in this paper. Its subreflector is replaced by two simple strips printed on the same supporting substrate of the exciter for ease and accuracy of fabrication. Measurements and simulations show that the proposed antenna can feature an improved operating bandwidth and broadside gain compared to reported conventional SBAs. Finally, high illumination efficiency of the bowtie exciter to the antenna aperture is highlighted by comparisons with an SBA excited by a straight dipole.