A multilayer radar-absorbing laminate includes three juxtaposed blocks. A first electrically conductive block is arranged toward the inside of the aircraft in use. A second electromagnetic intermediate absorber block has a layer of electrically non-conductive fiber sheets is permeated by graphene-based nanoplatelets to achieve a periodic and electromagnetically subresonant layer, the conductive layers containing graphene nanoplatelets alternating with non-conductive layers. A third block of electrically non-conductive material is arranged towards the outside and forms part of the outer surface of the aircraft. The second block is produced by depositing on the fiber sheets a suspension of graphene nanoplatelets in a polymeric mixture, with controlled penetration of the graphene nanoplatelets into the fiber sheets. A plurality of dry fiber sheets sprayed with the suspension of graphene nanoplatelets is superimposed. An unpolymerized thermosetting synthetic resin is infused into a lay-up made of the first, second and third blocks. Afterwards, the thermosetting resin is polymerized.

A radio wave absorbing member 1a includes a radio wave absorber 10 and a support 20 having a sheet shape. The radio wave absorber 10 includes a resistive layer 12, a reflective layer 14, and a dielectric layer 13. The reflective layer 14 reflects a radio wave. The dielectric layer 13 is disposed between the resistive layer 12 and the reflective layer 14 in the thickness direction of the reflective layer 14. The support 20 supports the radio wave absorber 10. The support 20 includes a matrix resin 20m and a flame retardant 20p.

A radio wave absorbing member 1a includes a radio wave absorber 10 and a support 20 having a sheet shape. The radio wave absorber 10 includes a resistive layer 12, a reflective layer 14, and a dielectric layer 13. The reflective layer 14 reflects a radio wave. The dielectric layer 13 is disposed between the resistive layer 12 and the reflective layer 14 in the thickness direction of the reflective layer 14. The support 20 supports the radio wave absorber 10. The support 20 includes a matrix resin 20m and a flame retardant 20p.

Methods and systems for a passive noise dampener. A system includes a hybrid fiber-coaxial network which carries content signals between a service provider system and premises, where the hybrid fiber-coaxial network is susceptible to receiving wireless noise signals, a plurality of passive noise dampeners, each passive noise dampener connected between the hybrid fiber-coaxial network and a premise of the premises. Each passive noise dampener includes an antenna based on medium used in the hybrid fiber-coaxial network. The antenna receives the wireless noise signals. A phase shifting device phase shifts 180 degrees phase shift the wireless noise signals received by the antenna to generate a counter signal. A directional coupler injects the counter signal into the hybrid fiber-coaxial network to mitigate impact of the wireless noise signals received by the hybrid fiber-coaxial network on the content signals. The antenna, the phase shifting device, and the directional coupler are passive devices.

Methods and systems for a passive noise dampener. A system includes a hybrid fiber-coaxial network which carries content signals between a service provider system and premises, where the hybrid fiber-coaxial network is susceptible to receiving wireless noise signals, a plurality of passive noise dampeners, each passive noise dampener connected between the hybrid fiber-coaxial network and a premise of the premises. Each passive noise dampener includes an antenna based on medium used in the hybrid fiber-coaxial network. The antenna receives the wireless noise signals. A phase shifting device phase shifts 180 degrees phase shift the wireless noise signals received by the antenna to generate a counter signal. A directional coupler injects the counter signal into the hybrid fiber-coaxial network to mitigate impact of the wireless noise signals received by the hybrid fiber-coaxial network on the content signals. The antenna, the phase shifting device, and the directional coupler are passive devices.

An FSS unit element includes: multiple conductors extending outward from the central portion of the FSS unit element; and at least one circuit element connected to the multiple conductors at the central portion of the FSS unit element, and disposed with fewer than the number of the multiple conductors.

An antenna structure and an electronic apparatus are provided. The antenna structure includes a substrate, a first radiation part, and a second radiation part. The substrate has a first surface and a second surface opposite to each other. The first radiation part is disposed on the first surface. The first radiation part is an absorber material. The second radiation part is disposed on the second surface. The second radiation part is coupled to a feeding part. There is a distance between the second radiation part and the first radiation part, so as to excite a first resonance mode through the coupling of the second radiation part to the first radiation part. Accordingly, the specific absorption rate (SAR) value of the electromagnetic wave is reduced.

An antenna structure and an electronic apparatus are provided. The antenna structure includes a substrate, a first radiation part, and a second radiation part. The substrate has a first surface and a second surface opposite to each other. The first radiation part is disposed on the first surface. The first radiation part is an absorber material. The second radiation part is disposed on the second surface. The second radiation part is coupled to a feeding part. There is a distance between the second radiation part and the first radiation part, so as to excite a first resonance mode through the coupling of the second radiation part to the first radiation part. Accordingly, the specific absorption rate (SAR) value of the electromagnetic wave is reduced.

An apparatus for electromagnetic wave evaluation may include: an electromagnetic wave non-reflecting outer structure in which electromagnetic wave absorbers are installed on interior walls and an evaluation space is formed therein; a building-simulating structure which is installed in the evaluation space inside the electromagnetic wave non-reflecting outer structure and in which electromagnetic wave absorbers capable of adjusting a quality factor are installed; a transmitting end installed inside or outside the building-simulating structure in the evaluation space and transmitting an electromagnetic wave; and a receiving end installed outside or inside the building-simulating structure in the evaluation space.

Provided is an apparatus and method for radar calibration that utilizes external shielding structures to be constructed around the body frame of a system to manage external signature presence and block unwanted signal emissions and intrusions. The inventive structures can adapt to desired user requirements or to environmental change as needed. The variable shielding with isolating connectors to the body frame of the system allows for aerodynamic needs to be sustained due to the mesh design while also protecting against electromagnetic spectrum interference and electro-optical short wave and long wave infrared signature emissions. The shielding can also be formed to emit a known or desired radio frequency response based on geometric shapes in order to influence radar cross-section readings. Communication with external environment is completed through the use of the shielding as a series of antennas.