Air and Metal Vias Combined Metamaterial-Based Lens for Radiation Performance Enhancement of Short-Pulse Tapered Slot Antenna

Abstract

A post-wall-structured tapered slot antenna (PWTSA) loaded with an embedded metamaterial-based lens (metalens) is proposed and investigated for short-pulse applications. The proposed embedded metalens consists of not only a metallic delay lens, but also an airy acceleration region surrounding the lens, which is different from the conventional metalenses used in various tapered slot antennas and can exhibit a small equivalent permittivity. Therefore, the embedded metalens has a large usable range of permittivity and does not increase the size of the original prototype PWTSA. The post-wall structure and metalens of the proposed antenna can help it achieve a comprehensive and balanced performance, including a high fidelity, low cross-polarization, stable main-lobe direction and gain enhancement. The simulated and measured results show that without any increase in antenna size, the proposed antenna enhances the realized gain by 6.4 dB over the frequency range from 9 to 26 GHz and achieves a stable radiation with the offset of the main-lobe direction being confined to 2° up to 24.9 GHz. Furthermore, the cross-polarization levels are less than −20 dB and the fidelity is kept high for the short-pulse radiation with the frequency spectrum up to 30 GHz.

Holey SIW Horn Antenna Based on an H-Plane Lenswise Wavefront Collimation

“…These SW structures have been implemented in conventional rectangular waveguide for H-plane horns as metal pins [14], [15] and for SIW horns as metallized blind via-holes [16]. A combination of structures that produce lower and higher phase velocity by using embedded vias and air hole arrays, respectively, is presented in [17] but for a tapered slot antenna.…”