Design of 77 GHz half‐shorted horn antenna with metamaterial lens

Abstract

In this article, we present new two‐layer and light‐weighted grid wire metamaterial lens implemented on the aperture of conical horn antenna to manufacture a small‐sized and high‐performance antenna applied in 77 GHz radar system. It could shorten half‐length of horn antenna without deteriorating its gain, broadband, and matching performance. The metamaterial lens is made by thin copper sheet whose thickness is only 0.1 mm. The measured results show that the metamaterial lens enhances the gain about 3.4 dB (@77 GHz) than short ordinary antenna with the same physical dimension, which equals to double its length. The high‐performance and small‐sized bulk make it suitable for 77 GHz radar system.

Wide-band gain enhancement of a pyramidal horn antenna with a 3D-printed epsilon-positive and epsilon-near-zero metamaterial lens

“…More uniform phase distribution results in higher gain and directivity [30]. The phase at the center and edge of the aperture can be expressed in terms of horn length L , metamaterial thickness d , and relative permittivity of metamaterial ɛ MM [12]: …”

“…The metamaterial lens that consists of a two-layer grid wire with ENZ characteristics at the edges and epsilon-positive (EPS) characteristics around the horn axis is placed at the aperture of the horn. This concept is applied to the aperture of a conical horn antenna and proved its usage for 77 GHz radar systems [12].…”

“…(2) A new procedure is introduced for the placement of a flat, metamaterial lens at the aperture of the horn antenna. With this technique, a three-layer EPS-ENZ metamaterial lens fits the tapered flaring of the horn and gain enhancement at a broader band is achieved compared to prior works [11, 12]. (3) The design of EPS-ENZ region located at the pyramidal horn aperture is asymmetric enabling low reflections.…”

Analytical approach for calculation of aperture efficiency enhancement of horn antennas using a thin metal cylinder

“…One of the recently used methods for performance improvements of aperture antennas consisting of both the unit and array antennas is by placing geometric structures or materials in front of the antenna aperture 1–4 . In aperture antennas such as horn antennas, antenna gain as well as the antenna aperture efficiency are increased with structures such as metamaterial, dielectric lens, and frequency selective surface in front of the antenna or inside antenna structure 5–14 . In Wang and colleagues, 15,16 the amplitude distribution of the electric field in the antenna aperture is improved by placing thin, in which the radius much smaller than the wavelength, dipole array on the antenna aperture.…”

“…[1][2][3][4] In aperture antennas such as horn antennas, antenna gain as well as the antenna aperture efficiency are increased with structures such as metamaterial, dielectric lens, and frequency selective surface in front of the antenna or inside antenna structure. [5][6][7][8][9][10][11][12][13][14] In Wang and colleagues, 15,16 the amplitude distribution of the electric field in the antenna aperture is improved by placing thin, in which the radius much smaller than the wavelength, dipole array on the antenna aperture. In these same studies, this structure reduced the phase errors in the antenna aperture and enabled the horn antenna to be made in a lower profile.…”