Article

Proximity Study of a UWB Directional Conformal Antenna on Water Pipe

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Abstract

A preliminary study on the conformal properties of an antipodal exponentially tapered antenna placed on the surface of a flow meter system in the UWB range is presented. It was observed that the water effect can be mitigated by shifting the antenna away from the pipe surface.

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... Content may change prior to final publication. [49], [91] Substrate Parameters: Size, gain, efficiency, bandwidth [92], [93] Advantages: Substrate with low permittivity and loss tangent gives high gain, high efficiency and wide [94] bandwidth while substrate with high permittivity improves return loss and reduces antenna size. Disadvantages: Substrate with low permittivity and low loss tangent are costly and not easily available. ...
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... materials on curve surfaces. For instance, a Vivaldi conformal antenna mounted on a pipe was proposed in [11]. This design works from 5.1 GHz to 11 GHz. ...
... Reviewing the literature of UWB conformal antennas, we can find some antenna designs manufactured with flexible materials on curve surfaces. For instance, a Vivaldi conformal antenna mounted on a pipe was proposed in [11]. This design works from 5.1 GHz to 11 GHz. ...
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... However, due to the conductivity of the human body, the backward radiation in the direction -z is decreased. On the other hand, when the antenna is mounted on the surface of a water-filled container, due to the high dielectric constant of water, dielectric resonance will occur, causing greater backward radiation [20]. ...
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... The dielectric resonance takes place because of the high dielectric constant and the low conductivity of water. 15 ...
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... The effects of mechanically curving the substrate on the antenna's performance have also been presented in section 4 of this paper. A study of a UWB directional antenna placed conformally on a cylindrical pipe section was reported in [8]. For realistic results, the edgefeeding mechanism is adopted for the curved substrate and results for concave and convex bending are noticed. ...
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The Vivaldi antenna and its feeding transition is investigated. A tapered transition from microstrip to symmetric double sided slot line, fabricated on a low dielectric constant substrate, exhibits a very wide operating frequency range, with no need for a shorting hole. The parameters of the antenna which influence the constancy of beamwidth with frequency are discussed, and the ability to determine the required beamwidth by controlling the antenna length is shown.
Full W-band high-gain LNA in mHEMT MMIC technology, European Microwave Integrated Circuits Con-ference
  • W Ciccognani
W. Ciccognani et al., Full W-band high-gain LNA in mHEMT MMIC technology, European Microwave Integrated Circuits Con-ference (2008), 314–317.