Super-wideband BAVA with enhanced radiation characteristics using an integrated biconvex magneto-electric lens for 5G mmWave communications

A super-wideband balanced antipodal Vivaldi antenna (BAVA)is proposed incorporating two pairs of lenses integrated within the tapered slot region. The first pair consists of biconvex magneto-electric lenses (ME-L), oriented horizontally with respect to the slot axis, while the second pair comprise biconvex electric lenses (E-L), positioned orthogonally to the ME-L. Through a controlled field shaping, the ME-L pair enables efficient field coupling to enhance mode symmetry across the tapered arms and provides a smoother impedance transition to free space. In contrast, the E-L pair introduces predominantly electric-field coupling. Both lens pairs act as phase-correcting directors that redistribute the aperture’s electric field, resulting in a more uniform phase front, increased gain, and improved beam confinement. In addition, several open-ended elliptical slits are incorporated within the tapered arms to enhance broadband impedance matching at the lower end of the operating band. The antenna exhibits an excellent reflection coefficient across the 5–40 GHz frequency range and demonstrates a directive end-fire radiation pattern, with a maximum measured gain of 14.5 dBi within the 20–30 GHz band. Furthermore, stable radiation characteristics are observed, with a beam squint less than 2° over the 10–40 GHz range. The antenna features a compact, low-profile, and fully planar structure. Unlike conventional dielectric lenses, which are often sensitive to alignment and integration tolerances, the proposed ME-L and E-L lenses enable seamless integration with the antenna structure and support automated fabrication processes.