Materials and methods for mitigating passive intermodulation. A membrane for reducing passive intermodulation includes a first polymeric layer, a second polymeric layer, and a continuous metal layer encapsulated between the first and second polymeric layers. A self-adhesive radio frequency barrier tape includes a waterproof polymeric top layer, a metal-containing layer adhered by an adhesive layer to the polymeric top layer, a pressure sensitive adhesive layer adhered to the metal-containing layer, and a release liner on a bottom surface of the pressure sensitive adhesive layer. A method of mitigating passive intermodulation includes passing a probe over an area of interest, the probe being sensitive to an intermodulation frequency of interest, and identifying a suspected source of passive intermodulation when the amplitude of the probe output exceeds a threshold at the frequency of interest. The method further includes covering the suspected passive intermodulation source with a radio frequency barrier material.

Materials and methods for mitigating passive intermodulation. A membrane for reducing passive intermodulation includes a first polymeric layer, a second polymeric layer, and a continuous metal layer encapsulated between the first and second polymeric layers. A self-adhesive radio frequency barrier tape includes a waterproof polymeric top layer, a metal-containing layer adhered by an adhesive layer to the polymeric top layer, a pressure sensitive adhesive layer adhered to the metal-containing layer, and a release liner on a bottom surface of the pressure sensitive adhesive layer. A method of mitigating passive intermodulation includes passing a probe over an area of interest, the probe being sensitive to an intermodulation frequency of interest, and identifying a suspected source of passive intermodulation when the amplitude of the probe output exceeds a threshold at the frequency of interest. The method further includes covering the suspected passive intermodulation source with a radio frequency barrier material.

A radio wave reflection reducing sheet provided with a laminate having a first primary surface and a second primary surface is disclosed. The laminate has: a first resin foam layer having a thickness from 0.05 to 3.00 mm and a density from 0.10 to 0.85 g/cm.sup.3, and a second resin foam layer having a thickness from 0.05 to 3.00 mm and a density from 0.20 to 0.90 g/cm.sup.3. The density of the second resin foam layer is greater than the density of the first resin foam layer. The first resin foam layer and the second resin foam layer are disposed in this order from the first primary surface side.

Provided is an antenna device including an antenna unit including a rectifier circuit that receives electric field energy of a radio wave or a quasi-electrostatic field (near field) in a space and rectifies an AC signal into a direct current, the antenna unit including a first antenna element that is a conductor to be in contact with or connected to an industrial product metal portion and a second antenna element that is a conductor different from the first antenna element and provided not to be electrically connected to the industrial product metal portion, in which an input line output from the first antenna element to a rectifier circuit unit of the AC signal output from the antenna unit is connected to the rectifier circuit.

An assortment of radar sensors in different variant embodiments. Each radar sensor has: a housing terminated by a radome, a circuit board that is equipped on the side facing away from the radome with at least one radio-frequency module, and an antenna structure on the side of the circuit board facing the radome. The housing is realized identically in all variant embodiments. The antenna structure has a planar antenna structure in at least one variant embodiment, and has a hollow conductor structure in at least one variant embodiment.

An assortment of radar sensors in different variant embodiments. Each radar sensor has: a housing terminated by a radome, a circuit board that is equipped on the side facing away from the radome with at least one radio-frequency module, and an antenna structure on the side of the circuit board facing the radome. The housing is realized identically in all variant embodiments. The antenna structure has a planar antenna structure in at least one variant embodiment, and has a hollow conductor structure in at least one variant embodiment.

A radar-absorbing structure is disclosed which includes a fiber, at least one binding agent disposed on the fiber and thus enabling the fiber to bind to another fiber.

An n-phonic energy detection (“NED”) system includes two antenna structures separated by a distance and configured to be placed adjacent one of a pair of human ears. Each of the two antenna structures includes antenna elements. The NED system also includes speakers configured to be placed adjacent one of the pair of human ears. The NED system also includes radio frequency (“RF”) detectors configured to detect RF energy emitted from a source and received by the two antenna structures, and an amplifier that amplifies signals from the RF detectors and outputs the amplified signals to a computer and to the speakers corresponding to the antenna structure to be placed adjacent the same one of the pair of human ears.

A switchable wire includes filaments, each of which includes a heat-activated material layer that may be indirectly heated to change its state between different states having different electrical conductivity. In an example embodiment the indirect heating may be electrically resistance heating by passing electrical current through an electrically-resistive core of the filament. The heat passing through an electrically-insulative coating around the core, and into a heat-activated material layer around the electrically-insulative coating. The heat-activated material may be a chalcogenide material that is shiftable between a crystalline electrically-conducting state and an amorphous electrically-insulating state. The state of the material may be controlled by controlling the heating profile through controlling heating in the core. Many such filaments may be twisted together to form a switchable wire. Such wires may be used in any of a variety of devices where switchable electrical conductivity is desired.

Provided is a wave control medium capable of controlling waves while decreasing the size of a metamaterial or the like and increasing the bandwidth of the metamaterial or the like.

A wave control medium 10 is formed by combining at least two among a coil 11 and a coil 12 which are three-dimensional microstructures formed into a spiral structure, the coil 11 and the coil 12 including any one of a metal, a dielectric material, a magnetic material, a semiconductor, and a superconductor, or a material selected from a plurality of combinations of these materials, and having functions of a capacitor and an inductor. The coil 11 and the coil 12 form a capacitor between the lateral face of the coil 11 and the lateral face of the coil 12 facing each other, and form an inductor by forming a three-dimensional multiple resonance structure by the coil 11 and the coil 12 having a spiral structure.