A K-u-Band Dual Polarization Hybrid-Mode Horn Antenna Enabled by Printed-Circuit-Board Metasurfaces

作者：Wu Qi^*; Scarborough Clinton P; Martin Bonnie G; Shaw Robert K; Werner Douglas H; Lier Erik; Wang Xiande

来源：IEEE Transactions on Antennas and Propagation, 2013, 61(3): 1089-1098.

DOI：10.1109/TAP.2012.2227448

• Horn antennas
• hybrid-mode horns
• metasurfaces
• soft/hard horns
• soft/hard surface
• surface impedance

Metamaterials with properly engineered surface properties have been recently proposed for application in the design of broadband hybrid-mode horn antennas, such as soft and hard horns. In this paper, we present the design, fabrication, and measured results of a square dual-polarization horn antenna with thin metasurfaces lining the four walls, demonstrating broadband, negligible-loss hybrid-mode operation. By employing a powerful genetic-algorithm (GA) design optimization technique, we have dispersion-engineered low-index metaliners whose surface impedances satisfy the balanced hybrid condition across the K-u-band. The optimized metaliners were synthesized based on conventional printed-circuit board technology, leading to a lightweight and low-cost construction. To improve the cross-polarization response, a simple dielectric plug was placed in the throat of the horn to perform effective mode conversion. Measurements showed that the fabricated horn antenna prototype provided low sidelobes, low cross-polarization levels, and radiation patterns that are approximately independent of polarization. Excellent agreement was found between measured and simulated results across the entire band of operation. Both the far-field radiation patterns and the aperture field distributions confirm the hybrid-mode operation of the horn, validating the balanced metasurface design. This metamaterial-enabled antenna represents a low-cost alternative to other types of soft feed horns, such as corrugated horns.

• 出版日期2013-3