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At the expense of frequency narrowing, binary amplitude-only diffractive optical elements emulate refractive lenses without the need of large profiles. Unfortunately, they also present larger Fresnel reflection loss than conventional... more
At the expense of frequency narrowing, binary amplitude-only diffractive optical elements emulate refractive lenses without the need of large profiles. Unfortunately, they also present larger Fresnel reflection loss than conventional lenses. This is usually tackled by implementing unattractive cumbersome designs. Here we demonstrate that simplicity is not at odds with performance and we show how the fishnet metamaterial can improve the radiation pattern of a Soret lens. The building block of this advanced Soret lens is the fishnet metamaterial operating in the near-zero refractive index regime with one of the edge layers designed with alternating opaque and transparent concentric rings made of subwavelength holes. The hybrid Soret fishnet metalens retains all the merits of classical Soret lenses such as low profile, low cost and ease of manufacturing. It is designed for the W-band of the millimeter-waves range with a subwavelength focal length FL=1.58 mm(0.5l0) aiming at a compact antenna or radar systems. The focal properties of the lens along with its radiation characteristics in a lens antenna configuration have been studied numerically and confirmed experimentally,
showing a gain improvement of ,2 dB with respect to a fishnet Soret lens without the fishnet metamaterial.
showing a gain improvement of ,2 dB with respect to a fishnet Soret lens without the fishnet metamaterial.
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In the present paper the state of the art, possibilities, advantages and disadvantages of the patented corrugated horn antennas that combine horizontal and vertical corrugations is being covered. These rather new type and probably not... more
In the present paper the state of the art, possibilities, advantages and disadvantages of the patented corrugated horn antennas that combine horizontal and vertical corrugations is being covered. These rather new type and probably not very well known yet, corrugated horn profiles; combine in the same horn antenna both horizontal and vertical corrugations. This horn antenna produces with reasonable bandwidth,
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A new horn antenna profile is presented. This new profile based on Gaussian techniques offers the best solution when the requirements related to the radiation pattern are very stringent. Short-horn antennas with high-conversion efficiency... more
A new horn antenna profile is presented. This new profile based on Gaussian techniques offers the best solution when the requirements related to the radiation pattern are very stringent. Short-horn antennas with high-conversion efficiency to a fundamental Gaussian beam, and therefore, very low sidelobe and cross-pol levels in a wide-frequency band, could be obtained by using the design technique presented
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Corrugated horn antennas have been widely used as feedhorns for radio telescopes and radiometers. It is well known the corrugated horn high performance radiation patterns that have made them famous for very stringent applications as radio... more
Corrugated horn antennas have been widely used as feedhorns for radio telescopes and radiometers. It is well known the corrugated horn high performance radiation patterns that have made them famous for very stringent applications as radio astronomy requires. However, in the last decade some very important improvements have been made to corrugated horns in terms of length, return loss, sidelobe
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Telecommunication satellite horn antennas require now-a-days more and more stringent requirements based mainly in the increased bandwidth necessary to accommodate more transponders to increase the capacity of the new satellite services.... more
Telecommunication satellite horn antennas require now-a-days more and more stringent requirements based mainly in the increased bandwidth necessary to accommodate more transponders to increase the capacity of the new satellite services. In this aspect horn antennas play a key role in the development of wider bandwidth services on board satellites because they are usually the reason that limits bandwidth in
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Nowadays, an increasing number of applications need stable radiation patterns with low sidelobes and low crosspolar levels in a very wide bandwidth. Gaussian profiled horn antennas (GPRAs) have demonstrated their feasibility as one of the... more
Nowadays, an increasing number of applications need stable radiation patterns with low sidelobes and low crosspolar levels in a very wide bandwidth. Gaussian profiled horn antennas (GPRAs) have demonstrated their feasibility as one of the best solutions. A corrugated Gaussian horn antenna design with more than 40% bandwidth is proposed. The measured radiated far field patterns are in good agreement
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A new concept of a really compact corrugated horn antenna for global coverage with very low sidelobe and cross-polar level and quite wide bandwidth is presented in this letter. This consists on the concatenation of a choke antenna... more
A new concept of a really compact corrugated horn antenna for global coverage with very low sidelobe and cross-polar level and quite wide bandwidth is presented in this letter. This consists on the concatenation of a choke antenna together with a Gaussian profile horn antenna. A comparison of the performances of this horn design versus other author designs is included.
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Improving the of radio telescopes and ra- diometers and their associated receive subsystems translates into increasing the ground received signal-to-noise ratios. Therefore, low noise amplification with cooling operation is required. How-... more
Improving the of radio telescopes and ra- diometers and their associated receive subsystems translates into increasing the ground received signal-to-noise ratios. Therefore, low noise amplification with cooling operation is required. How- ever, the system designer must select an appropriate feedhorn antenna with low sidelobes and an adapted illumination at the edge of the reflector since the noise originated from the
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ABSTRACT The paper is devoted to EBG horn antennas. This novel type of all-dielectric horn antennas is based on complex hollow defects in woodpile structures and can be used for creating compact arrays and provide a promising solution for... more
ABSTRACT The paper is devoted to EBG horn antennas. This novel type of all-dielectric horn antennas is based on complex hollow defects in woodpile structures and can be used for creating compact arrays and provide a promising solution for submillimeter and terahertz devices. A novel concept of feeding EBG horn antennas via evanescent fields existing in periodic structures is presented. The principle of creating all-dielectric pyramidal horn antennas based on woodpile structure with hollow defects is proposed. Different horn antennas based on woodpile structures and characterized by large operating bandwidths and high levels of directivity and efficiency were designed, fabricated and measured.