There is provided an apparatus and method for disrupting radar systems. The apparatus comprises a chamber (110) for attachment to a vehicle, a radar countermeasure material (130) in the chamber, the radar countermeasure material comprising a plurality of hollow fibres, wherein the inner surface of at least some of the hollow fibres is at least partly coated with a conductive substance, and a release means (140) for dispensing the radar countermeasure material out of the chamber.

A radar radiation redirecting inhibition layer for reducing radar cross section (RCS) of radar radiation redirection pavement marking tapes, pavement marking cover tapes incorporating such layer and methods of use are described.

A method includes transmitting, by a radiofrequency identification (RFID) reader device, a first electromagnetic radiation at a first polarization to a scan area and second electromagnetic radiation at a second polarization to the scan area. Re-radiated first electromagnetic radiation is received from an RFID tag located in the scan area at the first polarization. Re-radiated second electromagnetic radiation is received from the RFID tag at the second polarization. A radar image is generated based on the first and second re-radiated electromagnetic radiation. One or more items of information encoded in one or more microstructure elements located on the RFID tag are decoded based on the generated radar image. An RFID reader device and an RFID system are also disclosed.

Radar radiation redirecting tapes (1, 2) include a first plurality of individual radar-reflecting directional antennae (5, 11). Each directional antenna comprises at least three elongate, unevenly spaced antenna conductors (10, 20, 30), arranged with their long extensions parallel to each other in the plane of the tape, such that the directional antenna is operable to reflect incoming radar radiation predominantly in a direction (80) which is orthogonal to the long extension of the antenna conductors and parallel to the plane of the tape.

A chaff electronic countermeasure device that includes an antenna element positioned on a substrate and in electrical communication with an integrated circuit. The conductive antenna element includes a conductive composition of a conductive polymer and graphene sheets. The device absorbs from a radar source a first radio frequency having a first amplitude. In response to absorbing the first radio frequency, the device reradiates at least a portion of a second radio frequency having a second amplitude toward the radar source, which results in an increased radar cross section of the device as perceived by the radar source. The second amplitude is higher than the first amplitude. The device is configured to be dispersed from a mobile platform. The device is configured to reradiate at least a second radio frequency toward the radar source, thereby resulting in an increased radar cross section of the device as perceived by the radar source

A multilayer thin film that reflects an omnidirectional structural color having a reflective core layer comprising a metallic material, a second layer extending across the reflective core layer, a third layer extending across the second layer, and an outer layer extending across the third layer. The multilayer thin film reflects a single narrow band of visible light that is less than 30° measured in Lab color space when viewed from angles between 0° and 45°, and the reflective core layer has a skin depth δ of greater than or equal to 1.0 μm in a frequency range from 20-40 GHz, as calculated by: $\delta =\sqrt{\frac{2\rho }{\left(2\pi f\right)\left({\mu }_0{\mu }_r\right)}}\approx 503\sqrt{\frac{\rho }{{\mu }_{r}f}},$
δ is skin depth in meters (m); ρ is resistivity in ohm meter (Ω.Math.m); f is frequency of an electromagnetic radiation in hertz (Hz); μ.sub.0 is permeability; and μ.sub.r is relative permeability of the metallic material.

A metallic component including NiCr and having a skin depth of greater than or equal to 1.0 m in a frequency range from 20-40 GHz, as calculated by: $=\sqrt{\frac{2}{\left(2f\right)\left({}_0{}_r\right)}}503\sqrt{\frac{}{{}_{r}f}}.$ In this equation, is skin depth in meters (m); is resistivity in ohm meter (.Math.m); f is frequency of an electromagnetic radiation in hertz (Hz); .sub.0 is permeability; and .sub.r is relative permeability of the NiCr metallic material. The metallic component may be a discrete metallic particle or a layer in a multilayer thin film.

A metallic component including a metallic material and having a skin depth of greater than or equal to 1.0 m in a frequency range from 20-40 GHz, as calculated by: $=\sqrt{\frac{2}{\left(2f\right)\left({}_0{}_r\right)}}503\sqrt{\frac{}{{}_{r}f}}.$
In this equation, is skin depth in meters (m); is resistivity in ohm meter (.Math.m); f is frequency of an electromagnetic radiation in hertz (Hz); .sub.0 is permeability; and .sub.r is relative permeability of the metallic material. The metallic component may be a discrete metallic particle or a layer in a multilayer thin film.

An antenna assembly tunable from remote comprising a main reflector a sub-reflector associated with the main reflector, and a feed adapted receive transmission illuminating the main reflector via the sub-reflector, or to transmit transmission to the main reflector via the sub-reflector. The sub-reflector comprising a plurality of actuators disposed over and attached to its outer face. Each of the actuators is adapted to locally deform the surface of the sub-reflector adjacent to that actuator in response to a change in the actuator position.

A multilayer thin film that reflects an omnidirectional structural color having a reflective core layer comprising a metallic material, a second layer extending across the reflective core layer, a third layer extending across the second layer, and an outer layer extending across the third layer. The multilayer thin film reflects a single narrow band of visible light that is less than 30 measured in Lab color space when viewed from angles between 0 and 45, and the reflective core layer has a skin depth of greater than or equal to 1.0 m in a frequency range from 20-40 GHz, as calculated by:

[00001]$=\sqrt{\frac{2}{\left(2f\right)\left({}_0{}_r\right)}}503\sqrt{\frac{}{{}_{r}f}},$

is skin depth in meters (m); is resistivity in ohm meter (.Math.m); f is frequency of an electromagnetic radiation in hertz (Hz); .sub.0 is permeability; and .sub.r is relative permeability of the metallic material.