Abstract: A radio wave absorbing panel is made up of a first insulating substrate and a second insulating substrate disposed in parallel a predetermined distance apart and a middle insulating substrate disposed between and parallel with the first and second substrates. The first and second substrates each have a conducting film coated over the entire surface of one side. On one side of the middle insulating substrate are coated multiple conducting films disposed in the form of stripes or a matrix. The width of each of the conducting films disposed in the form of stripes or a matrix is equal to or between 0.1 cm to 50 cm. By this means a thin radio wave absorbing panel having excellent radio wave absorption and transparency to light can be obtained.

Abstract: The present invention relates to a material of construction which includes a radar-dispersing metal foam, and to a vehicle to which a radar-dispersing metal foam has been applied. The radar-dispersing metal foam is capable of reducing the radar return from an object by a significant amount over a wide range of radar frequencies. The metal foam has a very low reflectivity to incident radar wave radiation.

Abstract: Disclosed is a device to conceal a radar fitted for example into a vehicle. This device bears especially a pattern. A method to make such a device is also disclosed. The device reproduces a given pattern comprising a shiny part. It comprises at least one front part transparent to optic waves and one part having a face with a shiny appearance before the rear face of the front part. The non-shiny part of the pattern covers the rear face of the front part. The invention can be applied especially to radars positioned on the front of vehicles. The cover then reproduces the manufacturer's logo.

Abstract: A non-skid, radar absorbing system 10. The system absorbs and scatters incident microwave and/or millimeter wave radiation so as to decrease retro reflectance. The system includes an absorbing layer (RAM) 14 juxtaposed with a substrate 12. Disposed adjacent the RAM 14 is a non-skid matrix layer 16 for providing a safe foot hold. Optionally, a protective environmental topcoat 18 is applied to the non-skid layer 16. The system has electrical and magnetic characteristics such that radar energy at a discrete or broadband frequencies is at least partially absorbed. The invention also includes methods of making and using the non-skid, radar absorbing system 10.

Abstract: An electromagnetic wave absorber including a mixture comprising a magnetic material particle and a binding material. The magnetic material includes a nucleus of an organic material and a magnetic material film is formed on a surface of the nucleus.

Abstract: An edge concealment system for abating electrical discontinuities between externally exposed edges of adjacent surface pieces separated by a gap. The system includes a cover component shrouding each edge and able to absorb or conduct incident radar energy. A male element and a female element extend between the cover component and the surface piece for positive engagement of the male element within the female element and retention of the cover component with the surface piece. Preferably the engagement of the male and female elements includes an audible signal such as a click sound when the engagement occurs so that operators are confirmatively advised upon positive placement.

Abstract: Variational calculus principles are applied directly to the radiation integral to minimize the radar signature of a two- or three-dimensional geometry. In the preferred embodiment, the radiation integral is minimized through the solution to a differential equation generated by Euler's calculus of variations (CoV) equation. When used in conjunction with a minimizing sequence, the analysis affords a broad search of all possible coefficient values to ultimately arrive at global minima. Compared to existing techniques, the approach locates local extrema quickly and accurately using fewer impedance matrix calculations, and optimization using the invention is possible over a wide band of frequencies and angles. The method is applicable to a wide variety of situations, including the design of stealth platforms.

Abstract: A glue-gun applied hot-melt radar-absorbing material (RAM) and method of use thereof is provided. The hot-melt radar-absorbing material composition comprises: (a) 70 to 85 wt % carbonyl iron powder; (b) 2 to 10 wt % of a metal deactivator; and (c) balance a thermoplastic polyurethane. The method for repair of a body comprising a radar-absorbing material, comprises: (a) formulating the hot-melt radar-absorbing material of the present invention; (b) forming the hot-melt radar-absorbing material into a shape; (c) applying the hot-melt radar-absorbing material in a molten state onto the body; and (d) allowing the hot-melt radar-absorbing material to cool to room temperature. The shape of the hot-melt RAM is advantageously a “glue stick”, which is configured to go into a glue gun. The repair operator loads the glue stick into the glue gun and pulls the trigger. The glue gun heats the glue stick, and the molten material is applied to the area to be repaired.

Abstract: The radio wave absorbent-assembling member comprises a radio wave absorptive thin material capable of assembling a structure in a desired form, wherein the thin material contains a conductive material therein and/or has on the surface thereof a conductive layer containing a conductive material, and a radio wave absorbent having a stereo-structure can be obtained by folding the above radio wave absorbent-assembling member and joining together the end portions of the thin material.

Abstract: A composite electromagnetic wave absorber capable of restricting the height of a pyramidal electromagnetic wave absorber and being applied to a compact anechoic chamber, wherein an upper absorber (3) is fabricated by dispersing ferrite powder in a general-purpose resin having a permittivity of not higher than 4.9.

Abstract: An electromagnetic wave absorber comprises: an electromagnetic wave reflector made of a metal plate; a tile-shaped first electromagnetic wave absorber section containing ferrite as a magnetic material and having surfaces one of which is adjacent to the wave reflector; and a second electromagnetic wave absorber section adjacent to the other surface of the first wave absorber section. The second wave absorber section includes a structure and a dielectric loss material. The structure includes a plurality of plate-shaped elements each of which is made of a magnetic loss material. These elements have surfaces that are located with specific spacing and orthogonal to the other surface of the first wave absorber section. The dielectric loss material is located at least part of the spaces between adjacent ones of the elements of the structure.

Abstract: A device to conceal a radar fitted into an automobile comprises at least one system of conductive wires perpendicular to the polarization of the wave sent out by the radar and reproducing a given graphic representation The graphic representation may be the automobile manufacturer's logo. The disclosed device can be applied especially to radars positioned in from of vehicles, for example of the ACC type.

Abstract: A gate such as a tollgate in an expressway for radar-mounted vehicles is disclosed, by which an erroneous operation of the mounted radar apparatus can be prevented and through which the radar-mounted vehicles can smoothly pass. The gate includes two partition walls which limit a passage. The positions of the front ends of the partition walls are separated in front and behind, or the front end of one or both of the partition walls has a structure for suppressing the frontward reflection of each radiated electric, optical, or acoustic beam incident on the relevant front end.

Abstract: A radome includes a liquid crystal layer, and control electrode layers and a power source for applying an electric field to the liquid crystal layer. The permittivity of the liquid crystal layer changes when an electric field is applied from the power source through the control electrode layers. Thickness and relative permittivity are selected to permit radio waves having the working frequency of a radar antenna to pass through during application of the electric field.

Abstract: A winged bomb is launched from a launch aircraft and glides to a target. During the glide the winged bomb follows a calculated guide path stored in a on board computer, with correction generated by the computer using data from an altimeter and global positioning receiver. Near the termination of the glide a television camera is activated and transmits signals to a remote location from which final correction are manually generated and transmitted by radio to the bomb. The bomb is designed with low radar cross section.

Abstract: There is provided an electromagnetic wave absorber in which uniformity, reproducibility and productivity are raised by forming a metal soft magnetic material flat plate, the surface of which is smoothed, of a regular shape disk or elliptical shape easily, at low cost, stably and certainly. In the electromagnetic wave absorber composed of a mixture of a magnetic material particle 21 and an organic binding material, the magnetic material particle 21 is constituted by a nucleus 22 made of organic material and a magnetic material film 23 formed on its surface.

Abstract: A method for producing a wave absorber, which method includes rubbing a mixture of a solidifiable fluid binder and a particulate dielectric loss material on a substrate and solidifying the binder, thereby to laminate a wave absorptive layer on the substrate, and a wave absorber produced by this production method are provided. According to the production method of the present invention, a structure including a dielectric loss material and a binder admixed most preferably for wave absorption can be formed easily into a long sheet or a long belt-like wave absorber.

Abstract: The present invention relates to an electromagnetic wave absorbers in broad bands, which can be efficiently produced by a simple method, thereby reducing production costs, and for which working efficiency can be improved due to a reduction in weight. The absorber is capable of efficiently absorbing electromagnetic waves in broad bands. The electromagnetic wave absorber in broad bands is constructed by attaching sintered ferrite magnetic bodies, in which lattice bar portions are disposed at appointed intervals, to a metallic reflection plate. The lattice bar portions of the sintered ferrite magnetic bodies are such that sintered ferrite plates of an appointed thickness are formed curved at a base width and a height where openings are provided at the respective bases of the lattice bar portions, so that the interval between openings are gradually made narrow from the base to the upper end and the top parts are caused to converge to a width almost coincident with the thickness of said sintered ferrite plate.

Abstract: An RF interface is configured as a laminate structure having a core layer of a ferromagnetic ceramic material, such as barium strontium titanate, whose permitivity is electrically controllable to modify the behavior of impinging electromagnetic energy, as one of minimally attenuated transmission, maximally attenuated absorption, and highly unattenuated reflection. Opposite surfaces of the ceramic core are coated with an electrically lossy material, such as indium tin oxide, to which a differential DC voltage is applied, and thereby imparting a DC electric field to the core layer. For an antenna application, during transmit/receive mode, the differential voltage has a magnitude that renders the laminate's core highly conductive, and thereby reflective to the RF wavelength being sourced from or received by an associated feed horn. During other times, the differential voltage renders the laminate effectively transparent to RF wavelengths in a prescribed band of interest (e.g.

Abstract: An electrically conductive member constituted by at least one member of the group consisting of carbon black, graphite and carbon fiber, a powdered or granulated material of an inorganic hollow body and inorganic reinforcing fiber are bonded to one another by an inorganic adhesive agent to thereby form an electric wave absorber. The electric wave absorber exhibits excellent electric wave absorbing power because of both the electrically conductive member and the powdered or granulated material of the inorganic hollow body which are contained in the electric wave absorber. The electric wave absorber has excellent mechanical strength because of the inorganic reinforcing fiber which is contained in the electric wave absorber. The electric wave absorber exhibits excellent nonflammable characteristic because of both the powdered or granulated material of the inorganic hollow body and the inorganic reinforcing fiber which are contained in the electric wave absorber.

Abstract: Novel test mounts are defined for a radar cross section testing apparatus that allows a supported object to be tested without interference from the test mount. This includes prescribing a diameter of about 0.61 wavelegths for a cylindrical test mount; maintaining a ratio for the test mount's characteristic dielectric constant and magnetic permeability of about one; and/or installing a frequency transposing apparatus to convert the frequency of radar pulses directed toward the test mount to off-frequency echoes.

Abstract: A thin sheet impedance device and process for controlling the resistance, capacitance and inductive properties of a material through the use of a plurality of impedance elements of specific sizes, shapes and material on one side of a thin dielectric sheet in combination with a plurality of similar impedance elements and/or a layer of resistive material on the opposite side of the dielectric sheet.

Abstract: A radio wave absorbing panel is made up of a first insulating substrate and a second insulating substrate disposed in parallel a predetermined distance apart and a middle insulating substrate disposed between and parallel with the first and second substrates. The first and second substrates each have a conducting film coated over the entire surface of one side. On one side of the middle insulating substrate are coated multiple conducting films disposed in the form of stripes or a matrix. By this means a thin radio wave absorbing panel having excellent radio wave absorption and transparency to light can be obtained.

Abstract: A transmission line electromagnetic reflection reduction treatment is disclosed herein. This invention relates to radar cross section reduction in vehicles including aircraft, submarines, warships, tanks, troop carriers, and mobile weapons, and reduction of electromagnetic (EM) interference from civil engineering structures including bridges, buildings, power lines, and antennas.

Abstract: The invention relates to a housing (1) with radar-absorbent properties, in particular for a radar sensor in a motor vehicle, with electrically conductive particles whose dimensions are adapted to the frequency of the radar beams to be absorbed. The housing (1) comprises a material that as its basic component contains plastic, either unreinforced or reinforced with glass fibers, selectively mineral-filled, and contains as an additive steel fibers (2) in a mixture such that the specific conductivity .sigma. of the housing adheres to a predetermined value.

Abstract: Ceramic radomes are fabricated using a method which reduces the dielectric losses of the ceramic material. A Si.sub.3 N.sub.4 ceramic powder is mixed with a suitable densification aid and then sintered to form a dense ceramic having a glassy phase. Silicon dioxide is then provided on the surface of the ceramic by packing it in silicon dioxide powder or by heating it in air to oxidize its surface. The ceramic and silicon dioxide are heated at a temperature sufficient to cause diffusion of impurities and additive cations from the glassy phase into the silicon dioxide. The surface of the ceramic is then ground to remove pits and to shape the ceramic into a radome.

Abstract: An incombustible wave absorber of the application-on-the-spot type includes a wave absorber body, and a cap attached to the absorber body wherein the absorber body is composed of a board for setting up a wave absorber made of a carbon-containing inorganic short fiber board or organic foam board and has folding portions and/or bonding portions which permit the board to be set up on the spot in the form of a hollow pyramid, wedge, polygon or corrugation, and the board is set up, on the spot, in the form of a hollow pyramid, wedge, polygon or corrugation to provide the absorber body, which is attached to the surfaces of walls, a ceiling or a floor of a field-free chamber.

Abstract: An electromagnetic wave absorber which is suitable for cellular phones, portable communication terminals and other portable electronic apparatus. The electromagnetic wave absorber is provided with a thin absorbing substrate formed of an electromagnetic wave absorbing material having a thickness of 0.01 .mu.m to 1.0 mm. Such a thin absorbing substrate is realized by making adjustment holes in the absorbing substrate and increasing a value of apparent magnetic permeability. Specifically, even in the absorbing substrate as thin as 0.8 mm, by making multiple adjustment holes, electromagnetic waves can be absorbed in a frequency ranging from 1.5 to 2.2 GHz.

Abstract: An absorber includes a plurality of shredded foam particles and a plurality of fiber whiskers. The fiber whiskers are interspersed among, and attach to the shredded foam particles to create a foam-fiber mixture. A curable adhesive is added to the foam-fiber mixture and the cured mixture is molded to form the radar absorber. The fiber whiskers are less than about two weight percent of the absorbers. The foam particles are preferably formed by shredding scrap foam. The particles are generally irregularly shaped and the size of the particles can be expressed as having a mean size of about 1/8" to 1" diameter, although the particles are not necessarily spherical. The fibers are about 1/8" to 3/4" in length and have a diameter of about 7.3 microns. To form the absorber, shredded foam particles are mixed with fiber whiskers, and the fiber whiskers attach themselves to the surface of the shredded foam particles.

Abstract: A portable enclosure for electromagnetic compatibility (EMC) testing, comprising, a flexible and vacuous arrangement that forms into an inflated arcuate framework having arched ceiling and side supports. The arcuate framework embodies a plurality of vertical arcuate structural members that are separated from one another and held in place by a multiplicity of vacuous and inflatable horizontal support members attached and pneumatically communicative to the vertical arcuate shaped members. After the flexible and vacuous structure is inflated, the arcuate framework is secured to the ground by means of guy-storms that are attached to each side of the plurality of vertical arcuate structural members. A flexible and conductive, two layered main shroud for covering the arched ceiling and side support areas that are defined by the inflated arcuate framework. A similar constructed two layered first and a second end capping shroud for covering, respectfully, front and rear openings of the arcuate framework.

Abstract: A wave absorber comprising first foamed particles comprising foamed particles of a thermoplastic organic polymer and a conductive layer formed on the surface thereof, and second foamed particles comprising foamed particles of a thermoplastic organic polymer, the first foamed particles and the second foamed particles being melt-adhered to each other, and a method for producing same. The wave absorber of the present invention is superior in a long-term shape retention, and shows superior wave absorption performance, thereby rendering itself suitable for use in an anechoic chamber.

Abstract: A measurement chamber which surrounds a target of interest intersected by a line defined by focal points associated with the measurement chamber and which separates and extracts scattered signals from the measurement chamber, includes a chamber having an interior defined by rotation of a nonlinear curve about the line, and first and second focusing elements which couple the scattered signals out of the measurement chamber. According to one aspect of the invention, the measurement chamber further includes first and second absorbing material sections which absorb the scattered signals, and which are disposed proximate to the distal ends of the first and second focusing elements, respectively.

Abstract: A method is presented for detecting a body at sea. A lidar system provided nboard an aircraft transmits radiation at a wavelength in the blue/green region of the energy spectrum towards the surface of the sea. The lidar system is tuned to receive return reflections occurring over a specified wavelength range. A shaped area located near the body is designed to inhibit any return reflections that would be detectable by the lidar system. The shaped area defines a shape that is abnormal for the area of the sea being searched and defines a size that is larger than the body. The presence of the body is indicated by a null return corresponding to the shape and size of the shaped area.

Abstract: Novel devices for providing shielding from and absorption of broadband electromagnetic radiation, and methods of manufacturing and using these devices, are disclosed. The device is comprised of a perforated electrical absorbing layer, containing conductive polymers, laminated to a metal plate. Additional layers may be incorporated into the device including one or more additional layers of electrical absorbing layers, magnetic absorbing layers and impedance matching layers.

Abstract: The attenuator is applicable to the art of identification, interrogation and communication equipment. The attenuator has particular application to equipment used in conjunction with smart cards, tags and like apparatus and including, in one form, an RF based technology, which has found a use in electronic ticketing, monitoring passenger movement and the identification and sorting of airline baggage and/or other items, such as containers or mail items. The attenuator, in one form, is predicated on the principle of creating a substantially opposing field, and applying this proximate the interrogator to substantially reduce stray field emissions. The attenuator, in another form, combines the physics of conducting tubes and self-cancelling fields and applies them to a tunnel interrogator. The attenuator thus applies a conducting tube which confines the field and the property of a loop generating a self-cancelling field to an interrogator. This combination may be called a "loop tube".

Abstract: A radio wave absorbent comprises an Ni--Cu--Zn base ferrite having a major composition comprising 49 to less than 50 mol % of Fe.sub.2 O.sub.3, 32 to 35 mol % of ZnO, 3 to 9 mol % of CuO and 9 to 14 mol % of NiO. The radio wave absorbent further contains an additive molybdenum oxide in an amount of greater than 0 to 0.10 wt %, calculated as MoO.sub.3, with the proviso that the total amount of the major composition is 100 wt %. The radio wave absorbent may be used as an exterior or interior material for a building or structure.

Abstract: The disclosed jacket comprises a layer that is discreet with respect to the visible and infrared frequencies, having a specified thickness, with a specified dielectric permittivity and emissivity close to 1 for the infrared frequency bands considered; a resistive layer, with an electrical resistivity and thickness that are determined so that the inverse of their product gives a specified resistance; a layer of dielectric material with a specified thickness and a specified dielectric permittivity; and a conductive layer with electrical conductivity determined so that it is considered as a reflective plane for the radar frequencies considered.

Abstract: A support member for a measurement chamber, which measurement chamber surrounds a target of interest intersected by a line defined by focal points associated with the measurement chamber, and which chamber separates and extracts unwanted scattered signals from the measurement chamber, the measurement chamber including a chamber section having an interior defined by rotation of a nonlinear curve about the line, and first and second focusing elements which couple the scattered signals out of the chamber section, includes a surface for attaching at least one of the target of interest and a source generating signals scattered by the target of interest and a sting element which is coaxial with the line and which is coincident with one of the focal points. According to one aspect of the present invention, the source is attached to the surface and supported by a sting element which is defined a body of rotation about the line.

Abstract: A low RCS measurement system includes a measurement chamber which surrounds a target of interest intersected by a line defined by focal points associated with the measurement chamber and which separates and extracts scattered signals from the measurement chamber system, the measurement chamber system including a chamber having an interior defined by rotation of a nonlinear curve about the line, and first and second focusing elements which couple the scattered signals out of the chamber, a signal source which emits signals along the line, wherein the emitted signals interact with the target of interest to thereby produce the undesirable scattered signals and desirable backscattered signals, a source support pylon which supports an output element of the source and which couples the scattered signals out of the chamber, and a target support pylon, which supports the target of interest at one of the focal points, and which is coaxial with the line.

Abstract: A wave absorber is provided which has a wave absorption characteristic of 20 dB in a frequency band of 1 GHz to 20 GHz, is nonflammable, compact and lightweight, and has excellent durability. A porous ferrite is produced as the base material for which is an Ni--Zn type ferrite which has an excellent wave absorption characteristic in the high frequency range, and this serves as a wave absorber formed in the shape of a pyramid or triangular prism.

Abstract: A wave absorber comprising a foamed resin and a dielectric loss material dispersed therein, wherein the foamed resin is a foamed melamine resin obtained by foaming a resin composition comprising, as the main components, a melamine-formaldehyde condensate and a foaming agent. The wave absorber alleviates the problems of the prior art, and is lightweight and superior in self-extinguishing property, and shows an excellent wave-absorbing property owing to a uniformly dispersed dielectric loss material.

Abstract: Protective device for protection of rapidly moving objects such as aircraft or the like against homing heads that react to radiation, in particular infrared radiation, emitted by the aircraft, and that have a destructive charge. The protective device has at least one dispenser arranged on the object to be protected, and at least one effective body (flare), such as a spot flare or the like, that can be launched therefrom. The effective body has at least one decoy charge that can be at least partially ignited at a distance from the object and which, upon decomposition, temporarily forms an apparent target body that spectrally simulates, in a way relevant to the homing head, the target signature of the object to be protected.

Abstract: The invention is a sealing assembly for reducing the gap between an aircraft's movable flight control member and adjacent structure thereto, the flight control member and structure having external surfaces and side surfaces facing each other. In detail, the assembly includes first and second flexible bulb seals mounted on the periphery of the side surface of both the flight control member and the adjacent structure forming an extension of the external surface of both. Each of the bulb seals includes a compressible foam bulk absorber core; the core having a bottom surface, a top surface generally parallel to the bottom surface, an outer side surface, and an inward facing surface at an acute angle to the top surface. A first sheet of dielectric material is bonded to the bottom surface of the core. A second sheet of flexible resistive material is bonded to the top, and sides of the core. A third sheet of flexible magnetic radar absorbing material is bonded to the second sheet.

Abstract: Microwave devices incorporate at least one photosensitive baffle that is selectively illuminated changing the baffle's electronic characteristic from being transparent to being reflective of microwave energy. The baffle serves as a gate, tuning element, reflector and the like. Various forms of photosensitive baffles and microwave devices are presented.

Abstract: The microwave absorption performance of a fiber loaded thermoplastic syntactic material is improved by geometrically reshaping the surface into a waffle shape. Starting with a fiber loaded version of thermoplastic syntactic foam, the front face geometry is then modified. Typically, the angle and frequency response is a function of both the front face angle and the skin thickness. These effects are minimized in this concept by using a pyramidal surface in which the field enters the material normal to at least one surface at almost all incident angles. The attenuation is over 20 dB, from S through Ku bands, over a broad angle range of up to 75 degrees off normal. An added benefit is that this system has a rigidity that is suitable for many structural applications.

Abstract: A broad-band radio wave absorber including a radio wave reflecting surface, and a plurality of magnetic members provided on the reflecting surface and arranged in columns and rows, each of the magnetic members being composed of a first layer in the form of a square tile or a cross and a second layer superimposed on the first layer and having at least one cylindrical block having a diameter smaller than the width of the first layer. The first layers of adjacent two magnetic members are in contact with each other. When the second layer has a plurality of cylindrical blocks, they are coaxially superimposed in turn in a step wise manner.

Abstract: An N-best feasible hypotheses multitarget tracking system for accurately detecting and tracking large numbers of closely spaced objects in a dense target environment in real time.

Abstract: A mixture of carbonyl iron powder and a silicone resin containing silica siloxane units and silanol groups can be stabilized for storage by mixing a stabilizing amount of an halosilane with the mixture; monochlorosilanes are preferred. The small amount of halosilane that is needed can be further reduced by vacuuming the mixture before adding the halosilane. The stabilized compositions are useful as reactive components in curable silicone mixtures.

Abstract: Radar attenuating compositions comprising a low viscosity siloxane polymer, a resinous crosslinker therefor and carbonyl iron powder have improved thermal stability when exposed to temperatures as high as 450.degree. F. The particular crosslinker that is used in the compositions of this invention provides improved stability for the compositions at room temperature storage conditions and also in the cured form. The compositions can be sprayed and/or molded and cured at room temperature and/or elevated temperatures, as desired.

Abstract: A vehicle in free space or air, with external surfaces primarily fashioned from planar facets. The planar facets or panels are angularly positioned to reduce scattered energy in the direction of the receiver. In particular, radar signals which strike the vehicle are primarily reflected at an angle away from the search radar or are returned to the receiver with large variations of amplitude over small vehicle attitude changes.