The reflect array system includes a resonant structure formed of an array of resonant cells and for passive reflection of incident signals. The resonant structure generates a radio frequency (“RF”) signal that is shaped and steered by the reflect array.

Metamaterials are described which can be employed with satellites, e.g., small sats, to increase the observability of such satellites. Any type of suitable metamaterial can be used. In exemplary embodiments fractal-based patterns or structures may be used.

The communication system as described herein includes an input feed, a source, and a tuner device. The input feed receives an input signal. The source emits a wireless signal based on the received input signal. The tuner device is disposed adjacent to the source emitting the wireless signal. The tuner device receives the wireless signal emitted from the source and produces a wireless output. In one embodiment, the tunable device includes multiple individually controlled window regions to control a radiation pattern of the wireless output transmitted from the tuner device.

The present invention provides wideband millimeter-wave SIW-fed FPC filtering antenna comprising a partially reflecting surface (PRS) and a filtering source configured to radiate a millimeter-wavelength electromagnetic wave. The filtering source comprises a conductive reflecting plane configured to work with the PRS to form a Fabry-Perot cavity; radiating elements including a pair of shorted radiating patches electrically connected to a ground plane through a pair of probes; and a substrate integrated waveguide (SIW) feeding structure coupled to the pair of radiating patches through a coupling aperture. The SIW-fed FPC filtering antenna has the advantages of wider bandwidth, higher directivity/gain, reduced structural complexity, compact size and appropriate feeding type for millimeter-wave applications.

Disclosed herein is an antenna device that includes a filter layer, an antenna layer, a divider layer, and ground patterns. The antenna layer has first and second radiation conductors and first and second ground pillars that surround the first and second radiation conductors, respectively. Each of the first and second ground patterns has a first area that overlaps a first space surrounded by the first ground pillars, a second area that overlaps a second space surrounded by the plurality of second ground pillars, and a third area that connects the first and second areas. A width of the third area in a width direction perpendicular to an arrangement direction of the first and second areas is smaller than a width of each of the first and second areas in the width direction.

A frequency selective surface (FSS) having periodicity between one eighth and one quarter of an operational wavelength of the FSS and a low profile. The FSS has multiple pattern elements which are used to produce multiple transmission poles, and in some embodiments multiple transmission zeros. The transmission poles and transmission zeros are in the Ka and Ku bands, making the FSS applicable to 5G application. The transmission poles and transmission zeros also have high angular stability an oblique incident angle as high as 60°, as well as polarization insensitivity.

A method and apparatus for impedance matching for an antenna aperture are described. In one embodiment, the antenna comprises an antenna aperture having at least one array of antenna elements operable to radiate radio frequency (RF) energy and an integrated composite stack structure coupled to the antenna aperture. The integrated composite stack structure includes a wide angle impedance matching network to provide impedance matching between the antenna aperture and free space and also puts dipole loading on antenna elements.

Provided is a technique for improving the radio wave transmission of a dielectric member, which reflects radio waves, without requiring a design change of the dielectric member itself. Provided is an antireflection material that is used by being laminated on a dielectric member, which reflects radio waves, to reduce the reflection of the radio waves. The dielectric member includes a base layer and a coating layer laminated on the base layer. The base layer has a thickness T.sub.YB of 1.2 mm or more and 3.5 mm or less. The coating layer has a relative permittivity ε.sub.YC of 3.0 or higher. The antireflection material has a thickness T.sub.X of 10 mm or less. The antireflection material has a relative permittivity ε.sub.X of 2.0 or more and 7.0 or less.

A unit cell for a hybrid bifocal antenna includes a top conductor layer, a bottom conductor, and at least three inner conductor layers between the top conductor layer and the bottom conductor layer. The inner conductor layers are stacked on top of each other and each includes a substrate layer. An inner patch antenna element is present between adjacent substrate layers.

Metamaterials are described which can be employed with satellites, e.g., small sats, to increase the observability of such satellites. Any type of suitable metamaterial can be used. In exemplary embodiments fractal-based patterns or structures may be used.