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Metamaterial Horn Antennas

The first decade of the 2000s saw an abundance of research on electromagnetic metamaterials, including metamaterial surfaces, high-impedance surfaces [18], electromagnetic band-gap materials [19], and artificial magnetic conductors (AMCs) [20, 21], all of which have shown promise for a variety of antenna applications. As hybridmode horn antennas required boundaries characterized by their anisotropic surface impedances, the design techniques that had previously been developed for other antenna applications could be readily adapted to create metamaterial surface designs for hybridmode horns. Applying those surface designs to actual horn antennas requires numerous modifications and approximations, one of which is the fact that tapered horn walls do not permit the direct placement of a surface that was designed to be periodic in two dimensions. The following sections provide details and examples for many of the design considerations that are relevant to the development of metamaterial horn antennas, including successful metamaterial implementations of hybrid-mode horns.

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Broadband Anisotropic Metamaterials for Antenna Applications
Zhi Hao Jiang, Jeremiah P. Turpin, and Douglas H. Werner Department of Electrical Engineering, Penn State University, University Park, PA 16802, USA dhw@psu.edu Artificially designed and structured electromagnetic materials, also known as metamaterials (MMs), allow the engineering...
(Broadband metamaterials in electromagnetics : technology and applications)
Broadband Low-loss Metamaterial- Enabled Horn Antennas
Clinton P. Scarborough,3 Qi Wu,a Douglas H. Werner,3 Erik Lier,b and Bonnie G. Martinb aDepartment of Electrical Engineering, Penn State University, University Park, PA 16802, USA bLockheed Martin Commercial Space Systems, Littleton, CO 12257, USA dhw@psu.edu Metamaterial surfaces...
(Broadband metamaterials in electromagnetics : technology and applications)
Horn Antennas as Reflector Feeds
Horn antennas have served in numerous applications for much of the last century, but most notably for their role as feeds for reflector antennas. The simplest horn antennas (such as that shown in Fig. 2.1) have radiation patterns much like those of open-ended waveguides, with relatively high sidelobes...
(Broadband metamaterials in electromagnetics : technology and applications)
Soft and Hard Horn Antennas
Hybrid-mode horns can be designed for tapered aperture distributions and thus low sidelobes (soft horns), uniform aperture distributions, and thus high sidelobes and maximum gain (hard horns), or for characteristics at nearly arbitrary points between the two extremes [3, 4]. Qualitatively, a soft surface...
(Broadband metamaterials in electromagnetics : technology and applications)
Octave-Bandwidth Single-Polarization Horn Antenna with Negligible Loss
Application Background The super-extended C-band presents one of the greatest challenges to traditional low-sidelobe horns, with its comparatively long wavelength requiring large, massive structures. The trifurcated horn does not require excessive mass at C-band compared to a simple horn, but...
(Broadband metamaterials in electromagnetics : technology and applications)
Dual-Polarization Ku-Band Metamaterial Horn
Application Background Many satellite communication systems employ dual-polarized Ku- band antennas, including corrugated horns as reflector feeds. Ku- band corrugated horns, while providing excellent performance over bandwidths approaching an octave, are relatively expensive to...
(Broadband metamaterials in electromagnetics : technology and applications)
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