Superdirective Broadside-Radiating Unidirectional Mixed-Multipole Antenna Arrays

A realistic superdirective broadside-radiating unidirectional mixed-multipole antenna (UMMA) design is presented and then used as the radiators of two two-element arrays. The single and two element systems are self-resonant in the 5G 28 GHz band being matched to <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">75 Ω</tex> sources without any intervening matching networks. Details of the designs along with their key performance attributes: directivity, realized gain, front-to-back ratio, radiation efficiency, and bandwidth, are given. It is demonstrated that these systems are not only highly efficient and have usable bandwidths, but they are all superdirective with their directivities surpassing several recognized bounds. They also further the recognition that traditional perceptions of superdirective systems being impractical are no longer tenable.