There is provided a radio wave absorber including a magnetic powder and a binder, in which a volume filling rate of the magnetic powder in the radio wave absorber is 35% by volume or less, a transmission attenuation amount is 8.0 dB or more, and a reflection attenuation amount is 8.0 dB or more.

There is provided a radio wave absorber including a magnetic powder and a binder, in which a volume filling rate of the magnetic powder in the radio wave absorber is 35% by volume or less, and a volume filling rate of a carbon component in the radio wave absorber is 0% by volume or more and 2.0% by volume or less.

Embodiments disclosed herein relates to a radar device, and more particularly, to a radar device having a structure that reduces the influence of an internal reflected wave, which is capable of preventing a target sensing performance from being deteriorated by a reflected wave reflected within the radar device, while having a cover structure that is capable of protecting an antenna from the outside.

A system comprises a first sensor on a first end of a vehicle and an on-board controller coupled to the first sensor. The first sensor is configured to detect a radio frequency (RF) signature of a marker along a guideway. The first sensor is a radar detection device. The on-board controller is configured to determine a first position of the vehicle on the guideway or a first distance from the position of the vehicle to a stopping location along the guideway based on at least the RF signature received from the first sensor. The marker is a metasurface plate comprising a first diffused element, a first retroreflector element, a first absorbing element and a second diffused element between the first retroreflector element and the first absorbing element.

Flame-resistant paper for radio wave absorber members includes 40 to 70% by mass of pulp; 5 to 50% by mass of aluminum hydroxide powder; and 3 to 15% by mass of a flame retardant consisting of a polyborate, wherein the flame retardant consisting of a polyborate is contained in an amount of 7 to 25% by mass relative to the amount of the pulp.

Flame-resistant paper for radio wave absorber members includes 40 to 70% by mass of pulp; 5 to 50% by mass of aluminum hydroxide powder; and 3 to 15% by mass of a flame retardant consisting of a polyborate, wherein the flame retardant consisting of a polyborate is contained in an amount of 7 to 25% by mass relative to the amount of the pulp.

An antenna module for a terminal includes an antenna and a Radiated Spurious Emission (RSE) improvement component. The antenna includes a feed source, a ground point, and at least one radiation arm. The RSE improvement component is coupled to the antenna for suppressing high order harmonics generated by the antenna when the antenna operates in a target frequency band, and includes a filter circuit configured to suppress the high order harmonics, and a control switch configured to control a working state of the filter circuit. The filter circuit can be a band stop filter circuit. The band stop filter circuit can be connected in series into the at least one target radiation arm of the antenna; or, a terminal of the band stop filter circuit is connected to the at least one target radiation arm of the antenna, and another terminal is connected to the feed source.

An antenna apparatus includes an electrically conductive section having peripheral edges, an antenna element coupled to the electrically conductive section, which transmits or receives electromagnetic signals, and an electromagnetic absorbing carbon material component. The carbon material component is generally disposed adjacent to the electrically conductive section, and includes a border region extending beyond the peripheral edges of the electrically conductive section. The carbon material component can be constructed of a carbon fiber fabric in which the carbon fibers are arranged to increase the effective signal to noise ratio of the antenna apparatus and enhance antenna performance without increasing the baseline power consumption level. The carbon fibers can be coated with silicone to insulate them externally while enhancing their lengthwise conductivity.

An antenna system and method for fabricating an antenna are provided. The antenna system includes a substrate and an antenna. The antenna includes a conductive particle based material applied onto the substrate. The conductive particle based material includes conductive particles and a binder. When the conductive particle based material is applied to the substrate, the conductive particles are dispersed in the binder so that at least a majority of the conductive particles are adjacent to, but do not touch, one another.

A detection-system for a vehicle to detect the presence of one or more object relative to the vehicle comprises a module-housing, a radar sensor component located within the module-housing for emitting a radar beam and receiving reflected signals in a detection mode. The radar sensor component comprises means for emitting a defrost beam in a defrost mode; the defrost beam overlapping the radar beam. The detection-system further comprises an absorber material located in the field of view of the defrost beam to absorb the energy of the defrost beam and to warm up in view to provide a defrosting effect.