US 12,749,818 B2 · Metal-only flat metasurface antenna

Abstract

A metal-only flat metasurface antenna is described. The antenna includes a pillbox beamformer combined with a metasurface structure provided by an array of non-resonant subwavelength unit elements having opening sizes that are strictly smaller than half of the guided-mode wavelength. The pillbox beamformer includes bottom and top parallel plate waveguides (PWPs) forming respective bottom and top cavities for propagation of the guided-mode. Bottom, middle and top metal plates form the two PWPs. Arranged at one end of the bottom and top PWPs is a respective parabolic structure. An all-metal horn structure is centrally arranged at a second end of the bottom PWP opposite the parabolic structure. According to one aspect, the horn structure includes a single feed port arranged at a focal point of the parabolic structure. According to another aspect, the horn structure includes two feed ports arranged at an offset of the focal point.

Claims24

Dependent claims

A metal-only flat metasurface antenna comprising:

a pillbox beamformer comprising a top metal plate, a middle metal plate, and a bottom metal plate of a same planar profile for provision of a top parallel plate waveguide stacked on a bottom parallel plate waveguide, the middle metal plate shared between the top and bottom parallel waveguides;
and
a metasurface structure formed in the top parallel plate waveguide and provided by an array of non-resonant subwavelength unit elements formed in the top metal plate,
wherein the pillbox beamformer and the metasurface structure are made exclusively from a metal material, and
wherein the top and bottom parallel plate waveguides form respective top and bottom air cavities for propagation of a guided-mode electromagnetic wave.

2 more elements

A shared-aperture metal-only flat metasurface antenna comprising:

a pillbox beamformer comprising a top metal plate, a middle metal plate, and a bottom metal plate of a same planar profile for provision of stacked top and bottom parallel plate waveguides with embedded parabolic structures, the middle metal plate shared between the top and bottom parallel waveguides and said parallel plate waveguides electromagnetically coupled to one another via a coupling slot formed in the pillbox beamformer;
and
a holographic metasurface structure formed in the top parallel plate waveguide and provided by an array of non-resonant subwavelength unit elements formed in the top metal plate, said metasurface structure configured to provide an aperture for simultaneous transmission of a transmit beam and reception of a receive beam, wherein each unit element comprises a rectangular slot having length and width that is smaller than, or equal to, 0.4 times a wavelength of the transmit or receive beam;
wherein
the top and bottom parallel plate waveguides form respective top and bottom air cavities for propagation of the simultaneous transmission of the transmit beam and reception of the receive beam,
the pillbox beamformer further comprises a horn structure in the bottom parallel waveguide, the horn structure comprising a transmit port for sourcing the transmit beam and a receive port receiving the receive beam, and
the pillbox beamformer and the holographic metasurface structure are made exclusively from a metal material.

4 more elements

Dependencies are inferred from the claim text.

Metal-only flat metasurface antenna

Life of this patent

Metal-only flat metasurface antenna

Life of this patent

Abstract

Claims24