Abstract: Techniques for implementing series-fed antenna arrays with a variable dielectric waveguide. In one implementation, coupling elements with optional controlled phase shifters are placed adjacent each radiating element of the array. To avoid frequency sensitivity of the resulting array, one or more waveguides have a variable propagation constant. The variable waveguide may use certain materials exhibiting this phenomenon, or may have configurable gaps between layers. Plated-through holes and pins can control the gaps; and/or a 2-D circular or a rectangular travelling wave array of scattering elements can be used as well.

Abstract: A leaky travelling wave array of elements provide a broadband radio frequency antenna.

Abstract: A dielectric travelling wave antenna (DTWA) using a TEM mode transmission line and variable dielectric substrate.

Abstract: Techniques for implementing series-fed antenna arrays with a variable dielectric waveguide. In one implementation, coupling elements with optional controlled phase shifters are placed adjacent each radiating element of the array. To avoid frequency sensitivity of the resulting array, one or more waveguides have a variable propagation constant. The variable waveguide may use certain materials exhibiting this phenomenon, or may have configurable gaps between layers. Plated-through holes and pins can control the gaps; and/or a 2-D circular or a rectangular travelling wave array of scattering elements can be used as well.

Abstract: A rectifier comprising a metal-insulator-metal (MIM) structure. The insulator may be a native oxide with an adjacent layer of graphene. In one implementation, the rectifier is used in an electromagnetic energy collector consisting of a planar waveguide formed of multiple material layers having at least two different dielectric constants. MIM rectifiers are aligned with mirrors are formed within the waveguide core. In some arrangements, a plurality of MIM rectifiers are disposed in a column or 3D array beneath each mirror.

Abstract: Techniques for implementing series-fed antenna arrays with a variable dielectric waveguide. In one implementation, coupling elements with optional controlled phase shifters are placed adjacent each radiating element of the array. To avoid frequency sensitivity of the resulting array, one or more waveguides have a variable propagation constant. The variable waveguide may use certain materials exhibiting this phenomenon, or may have configurable gaps between layers. Plated-through holes and pins can control the gaps; and/or a 2-D circular or a rectangular travelling wave array of scattering elements can be used as well.

Abstract: A planar fixed area thin film antenna-coupled metal-insulator-metal (MIM) rectifier of arbitray metal with a native nickel oxide insulator. Devices can be designed for millimeter wave, IR, NIR and visible wavelengths.

Abstract: The use of rectennas, or antenna-coupled rectifiers, using metal-insulator-metal tunnel diodes as rectifiers for energy conversion has been explored with more fervor recently, given the advances in nanotechnology fabrication and increased resolution of features. Some have made these devices from symmetric metals (e.g. Ni—NiO—Ni) and asymmetric metals (e.g. Al—AlOx/Pt), and have used deposited oxides as well as native oxides. One key to obtaining a highly asymmetric device with efficient current generation needed for high conversion efficiency is to instead use dissimilar metals and a thin reproducible oxide. The described method allows for a thin, reproducible native oxide of nickel be integrated with any antenna metal to overcome oxide surface roughness problems that typically hamper the practicality of these devices.

Abstract: An electromagnetic energy concentrator uses a prism and waveguide with a gap layer of uniform thickness disposed between the prism and a first surface of waveguide. Energy detectors, which may be photovoltaics or miniaturized antenna elements are disposed adjacent to and co-extensive with a second surface of the waveguide. The detectors operate in each of at least two bands; a distance between detectors operating in a given band depends on a wavelength in the given band.

Abstract: A rectifier comprising a metal-insulator-metal (MIM) structure. The insulator may be a native oxide with an adjacent layer of graphene. In one implementation, the rectifier is used in an electromagnetic energy collector consisting of a planar waveguide formed of multiple material layers having at least two different dielectric constants. MIM rectifiers are aligned with mirrors are formed within the waveguide core. In some arrangements, a plurality of MIM rectifiers are disposed in a column or 3D array beneath each mirror.

Abstract: A leaky dielectric travelling wave surface waveguide antenna provides a multiband, low-profile antenna for satellite and other wideband (Ku/K/Ka/Q) communications applications. The antenna structure can be arranged into various types of arrays to yield a cost-effective, wideband/multiband operation with high power. In one implementation, the antenna includes a waveguide having a multi-layer substrate, a top surface, a feed (excitation) end, and a load end. One or more scattering features are disposed on the top surface of the waveguide or within the waveguide, and achieve operation in a leaky propagation mode. A wavelength correction element adds linear delay to incident energy received or transmitted by the antenna. The resulting structure permits a resulting beam direction of the antenna to be independent of the wavelength.

Abstract: Techniques for implementing series-fed antenna arrays with a variable dielectric waveguide. In one implementation, coupling elements with optional controlled phase shifters are placed adjacent each radiating element of the array. To avoid frequency sensitivity of the resulting array, one or more waveguides have a variable propagation constant. The variable waveguide may use certain materials exhibiting this phenomenon, or may have configurable gaps between layers. Plated-through holes and pins can control the gaps; and/or a 2-D circular or a rectangular travelling wave array of scattering elements can be used as well.

Abstract: A dielectric travelling wave antenna (DTWA) using a TEM mode transmission line and variable dielectric substrate.

Abstract: Techniques for implementing series-fed antenna arrays with a variable dielectric waveguide. In one implementation, coupling elements with optional controlled phase shifters are placed adjacent each radiating element of the array. To avoid frequency sensitivity of the resulting array, one or more waveguides have a variable propagation constant. The variable waveguide may use certain materials exhibiting this phenomenon, or may have configurable gaps between layers. Plated-through holes and pins can control the gaps; and/or a 2-D circular or a rectangular travelling wave array of scattering elements can be used as well.

Abstract: A low profile antenna using a cavity-backed central radiating surface surrounded by one or more ground plane surfaces. Passively reconfigurable structure provide frequency dependent coupling between the surfaces. The frequency dependent couplings may be implemented using meander line structures, Variable Impedance Transmission Lines (VITLs), or tunable VITLs that used interspersed electroactive sections.

Abstract: A cylindrically symmetric satellite antenna that provides directional and omnidirectional operating modes in a compact form factor. Feed points located at the top of the cylindrical structure provide increased platform isolation. Combining networks, disposed below or within the cylindrical structure, may be replaced with inexpensive baluns composed of coaxial line sections.

Abstract: Techniques for implementing series-fed antenna arrays with a variable dielectric waveguide. In one implementation, coupling elements with optional controlled phase shifters are placed adjacent each radiating element of the array. To avoid frequency sensitivity of the resulting array, one or more waveguides have a variable propagation constant. The variable waveguide may use certain materials exhibiting this phenomenon, or may have configurable gaps between layers. Plated-through holes and pins can control the gaps; and/or a 2-D circular or a rectangular travelling wave array of scattering elements can be used as well.

Abstract: Dispersive properties of a linear dispersive delay line are retained in a spiral configuration by constraining the radius of curvature depending on a desired propagation mode. The compact form factor spiral can be either a continuous spiral or a piecewise linear approximation. The spiral comprises a highly dielectric waveguide such as titanium dioxide or barium tetratitanate. Preferably, a spacer with a low dielectric constant and a microstrip are disposed on the top surface. The microstrip prevents attenuation of low frequencies, thereby increasing the operating frequency range. A second dielectric spacer and a second microstrip can be deposited on the bottom surface of the waveguide. Alternatively, the bottom surface of the waveguide can face a ground plane. The waveguide can be fed by horns or half-horns.

Abstract: Nuclear quadrupole resonance measurement using two or more wire loop(s) within a space to define a portal, and driving the wire loop(s) with a baseband digital transmitter generating a chirped or stepped signal, to create a corresponding varying electromagnetic field within the portal. Coherent emissions reflected thereby are detected through a directional coupler feeding the transceiver. The detected coherent emissions are processed with a matched filter to determine presence of a target object within the portal.

Abstract: An electromagnetic energy collector includes a planar waveguide formed of multiple material layers having at least two different dielectric constants. Mirrors formed within the waveguide core. Metal-insulator-metal (MIM) detectors are aligned with the mirrors, and disposed below the bottom surface of the waveguide. The mirrors may be etched at an angle into the waveguide. In some arrangements, wherein a plurality of MIM detectors are disposed in a column or 3D array beneath each mirror. A wavelength range of the MIM detectors disposed closer to a respective mirror is lower than a wavelength range of a MIM detector disposed farther away from the same mirror.