Abstract: An electromagnetic antenna includes a channel configured to serve as a waveguide for electromagnetic radiation, a first and second feed disposed next to each other inside the channel at a first end thereof, the first and second feed being configured to radiate electromagnetic waves into the channel, an aperture lens disposed inside the channel near a second end thereof opposite to the first end, the aperture lens being configured to output collimated beams, a first focal lens disposed inside the channel adjacent to an outlet of the first feed, the first focal lens being configured to squint a beam radiated from the first feed toward a center of the aperture lens, and a second focal lens disposed inside the channel adjacent to an outlet of the second feed, the second focal lens being configured to squint a beam radiated from the second feed toward the center of the aperture lens.

Abstract: A communication apparatus includes a first antenna array with plurality of antenna elements multiple antenna elements and first plurality of thermoelectric devices distributed across the plurality of antenna elements. An activation or a deactivation of each thermoelectric device is executed in a real-time or near real-time based on an operational state of each antenna element of the plurality of antenna elements and a performance state of the plurality of antenna elements, where the activation or the deactivation is performed in a defined delayed time after a defined time has elapsed from a start of operation of the first antenna array to mitigate performance degradation of the plurality of antenna elements when in operation. Adaptive cooling is applied by each thermoelectric device on different subsets of antenna elements such that performance breakdowns due to heating of a plurality of chips associated with the different subsets of antenna elements is reduced.

Abstract: A transmission method includes: in a first period, causing a light source to emit light having a first luminance; and in a second period, causing the light source to transmit an optical signal by causing the light source to alternately emit light having a second luminance and light having a third luminance lower than the second luminance.

Abstract: The invention relates to a flying apparatus for calibrating a radar system including: a base body, wherein the base body includes: at least one rotor adapted to generate lift, a drive configured to drive the rotor, and a control unit configured to control a flying operation of the flying apparatus; and a radar reflective structure, wherein at least one part of the radar reflective structure is movably mounted to the base body, and wherein the at least one part can be moved actively or passively.

Abstract: Provided is an antenna device with a simple configuration and in which it is possible to control the directivity in various directions. An antenna device according to the present invention is provided with: an array antenna that includes at least one antenna element disposed on a first surface of a substrate and that forms beams in respective directions having a plurality of angles including a first angle relative to the first surface of the substrate; and a side wall that is provided on at least a partial periphery of the at least one antenna element and that refracts, in a direction along the substrate, a first beam in the direction having the first angle.

Abstract: In order to avoid friendly fire incidents in the combat theater, novel covert identification systems and methods of identifying friendly forces are provided. The systems include at least a spectroscopic imaging device and a marker that interact with each other by using a synchronized, predetermined filter tuning sequence. The filter tuning sequence enables interacted photons to wavelength hop according to the predetermined tuning sequence. As a result, the covert identification system allows friendly forces to clearly identify each while avoiding detection by enemy forces that employ conventional broadband and night vision sensors.

Abstract: The present disclosure relates to reflector for non-contact radar-based fill level measurement in containers with floating roofs. The reflector is designed to be mounted on top of the floating roof, wherein the reflector comprises at least a surface, which is formed by an array of cavities. According to the present disclosure, the cavities have a tapered cross-section. By the tapered cavities the radar signals emitted by the fill level measuring device are reflected and focused towards the fill level measuring device, so that the receipt of the reflected radar signal by the fill level measuring device is ensured. Through this, the fill level measuring device can determine the fill level reliably based on the reflected radar signals.

Abstract: Described herein are devices incorporating Casimir cavities, which modify the quantum vacuum mode distribution within the cavities. The Casimir cavities can drive charge carriers from or to an electronic device disposed adjacent to or contiguous with the Casimir cavity by modifying the quantum vacuum mode distribution incident on one side of the electronic device to be different from the quantum vacuum mode distribution incident on the other side of the electronic device. The electronic device can exhibit a structure that permits transport or capture of hot carriers in very short time intervals, such as in 1 picosecond or less.

Abstract: Devices and methods for enhancing observability under ultrasound imaging of medical devices include temporal markers which are dynamic, producing a variable ultrasound image over time. Included are rotating markers which produce a Doppler shift visible through ultrasound imaging in a Doppler mode and which enhance visibility of the marker. Other devices and methods include alternating streams of fluid contrast agents and saline as well as destroying a fluid contrast agent stream with a high intensity ultrasound pulse.

Abstract: A dihedral shaped device is provided, which includes two plates forming between them an angle of [pi]?2[alpha], where 0<[alpha]<[pi]/4. Each plate has a ground plane, at least one dielectric layer and a network of radiating elements. An incident wave is reflected by the device by virtue of a double reflection from both plates. The network of radiating elements of each plate allows a phase shift to be generated, from the exterior towards the centre of the dihedron, along an axis perpendicular to an axis of intersection of the two plates, according to a set phase law, allowing a deviation to be introduced relative to a specular reflection for a given operating frequency.

Abstract: Systems and methods for determining the position of a buoyancy element in a marine survey are described in which a passive reflecting material is disposed on the buoyancy element to enable a radar on the vessel to detect the position of the buoyancy element. The radar may emit a frequency modulated continuous wave or a sequence of frequency modulated or phase modulated sinusoidal waves.

Abstract: Disclosed is a measurement device that can accurately measure size, position, the presence of an object, and the like by means of a simple and low-cost method. Specifically, disclosed is a measurement device that is provided with: a transmitter that transmits radio waves; a vibrating surface that vibrates mechanically; a receiver that receives radio waves; and a controller that transmits radio waves from the transmitter, and on the basis of the signal of the radio waves reflected by the vibrating surface and received by the receiver, outputs information about a measured object on the pathway between the transmitter and the receiver with the vibrating surface therebetween.

Abstract: An antenna device includes antennas, each of which includes antenna elements arranged in a longitudinal direction, arranged side by side in a transverse direction intersecting the longitudinal direction, wherein an interval between the antennas arranged side by side in the transverse direction is approximately 2? where ? is a free space wavelength corresponding to an operating frequency, and each of the antenna elements includes a horn formed therein.

Abstract: A reflector is arranged at a first position, which is assigned to a first end of the object. An antenna-system is arranged at a second position, which is assigned to a second end of the object. The antenna system contains a transmit antenna and a receive antenna, while the reflector and the antenna-system are coupled by a radio signal. The radio signal is sent from the transmit antenna via the reflector towards the receive antenna. The receive antenna is connected with an evaluation unit, which is prepared to measure the deflection between the first end of the object and the second end of the object based on the received radio signal.

Abstract: A wearable radar reflector includes a retroreflector configured to reflect radiation received from a vehicle, and incorporated into a garment worn by a pedestrian.

Abstract: A synthetic aperture radar's surveillance is defeated by electronic camouflage that employs a protective shield to cover an intended target. The shield intercepts and modifies the interrogating radar pulses by modulating incident radar pulses to produce radar echoes shifted in Doppler frequency, whereby the returned echoes give a false depiction of the target, even to smearing the radar display. New structures are presented that exhibit variable reflectivity and variable dielectric characteristics of particular use in the foregoing and other electronic systems.

Abstract: An electromagnetic reflector includes an antenna that receives an incoming signal and that transmits an outgoing signal. A three-port device, such as a circulator, has a first port electromagnetically coupled to the antenna. An RF circuit has an input that is electromagnetically coupled to the second port of the three-port device and an output that is electromagnetically coupled to the third port of the three-port device. The RF circuit changes at least one of a gain and a phase of the incoming signal to generate a desired outgoing signal that passes through the three-port device to the antenna.

Abstract: Disclosed is a measurement device that can accurately measure size, position, the presence of an object, and the like by means of a simple and low-cost method. Specifically, disclosed is a measurement device that is provided with: a transmitter that transmits radio waves; a vibrating surface that vibrates mechanically; a receiver that receives radio waves; and a controller that transmits radio waves from the transmitter, and on the basis of the signal of the radio waves reflected by the vibrating surface and received by the receiver, outputs information about a measured object on the pathway between the transmitter and the receiver with the vibrating surface therebetween.

Abstract: An antenna array for use within a microwave imaging system to capture a microwave image of a target is selectively programmed to optimize one or more parameters of the microwave imaging system. The array includes a plurality of antenna elements, each capable of being programmable with a respective phase shift to direct a beam of microwave radiation toward the target such that the microwave radiation from each of the plurality of antenna elements arrives at the target substantially in-phase. To optimize a parameter of the microwave imaging system, the phase shifts of selective ones of the antenna elements are altered, while still maintaining the substantially in-phase microwave radiation at the target.

Abstract: A reflector is arranged at a first position, which is assigned to a first end of the object. An antenna-system is arranged at a second position, which is assigned to a second end of the object. The antenna system contains a transmit antenna and a receive antenna, while the reflector and the antenna-system are coupled by a radio signal. The radio signal is sent from the transmit antenna via the reflector towards the receive antenna. The receive antenna is connected with an evaluation unit, which is prepared to measure the deflection between the first end of the object and the second end of the object based on the received radio signal.

Abstract: Control of a device including aiming a pointing device comprising a camera and a source of invisible light in the direction of an object associated with the device to be controlled, upon which object a number of retroreflective marker elements are positioned, which reflect at least a part of the invisible light emitted by the light source back to the pointing device; generating a first image of a target area aimed at by the pointing device whereby the light source is inactive; generating a second image of the target area aimed at by the pointing device whereby, invisible light is emitted by the light source in the direction of pointing; processing the target area images to determine the presence of retroreflective marker elements; using information pertaining to the retroreflective marker elements to identify the device to be controlled and/or to determine a control signal for the identified device.

Abstract: There is provided an apparatus for capturing cosmic background radiation and for converting cosmic background radiation into electricity. An antenna is configured so as to capture cosmic background radiation. An electrostatic electron multiplier is connected to the antenna. A high voltage power supply is connected to the electrostatic electron multiplier whereby cosmic background radiation is converted to electricity.

Abstract: A system and method for an aircraft (10) that provides an IR decoy (12) for an incoming missile (18) to track instead of an engine (14) of the aircraft (10) is disclosed. The IR decoy (12) is deployed during or just after take off, and prior to landing to provide a signature (16) for any incoming missile (18). The IR decoy (12) provides a heat source (16) that has a higher radiant intensity than the hottest heat source on the aircraft (10), which is typically the engine (14), thereby providing a more attractive heat source for the missile (18). In another embodiment, a warning system (20) for an aircraft (10) detects an incoming missile (18), and deploys IR decoy (12) and creates an engine mask (22) by injecting an additive into the exhaust stream of the engine (14), thereby obscuring the radiation emanating from the engine (14).

Abstract: A material of variable emissivity includes a first metallic layer having a first aperture, a second metallic layer having a second aperture, and a variable dielectric layer interposed between the first metallic layer and the second metallic layer.

Abstract: A chaff element for interfering with radar signals. The chaff element has a dielectric substrate and a pair of elongate electrically conductive elements, having a total length of approximately one-half wavelength of the radar signals or otherwise tuned to the radar signals, disposed on the dielectric substrate. A switch is arranged to electrically couple the pair of elongate elements together in response to a control signal generated by an oscillator circuit and a battery. The chaff element can be used in a method of providing a countermeasure against radar signals. A plurality of chaff elements can be deployed in an airspace above a radar unit emitting a radar signal and interfere with the radar signal by opening and closing the switches of the chaff elements while deployed in said airspace above the radar unit.

Abstract: The present invention relates to a decoy for deceiving radar systems, especially Doppler radar systems. The decoy comprises a corner reflector, where at least one of the surfaces (1) is arranged to be able to obtain a varying reflectivity for radar radiation, especially with a modulation frequency which in the reflected radiation causes Doppler sidebands of an extent that is usual for the radar application.

Abstract: Method for organizing computer operations on a system of parallel processors to invert electromagnetic field data (11) from a controlled-source electromagnetic survey of a subsurface region to estimate resistivity structure (12) within the subsurface region. Each data processor in a bank of processors simultaneously solves Maxwell's equations (13) for its assigned geometrical subset of the data volume (14). Other computer banks are simultaneously doing the same thing for data associated with a different source frequency, position or orientation, providing a “fourth dimension” parallelism, where the fourth dimension requires minimal data passing (15). In preferred embodiments, a time limit is set after which all processor calculations are terminated, whether or not convergence has been reached.

Abstract: A time-of-flight calibration system for a radar-based measurement device is provided. The time-of-flight calibration system includes a target antenna and a waveguide, e.g. a coaxial cable. The waveguide is coupled at one end to the target antenna and terminated at its other end by a wave-reflecting impedance.

Abstract: The invention relates to a method for photographing on board of a flying rotating body and system for carrying out said method. According to said invention, pictures (V0, V90, V180, V270) are taken at predetermined angular positions of said flying body by a device which is rigidly fixed to the front thereof and are exposed to an image geometrical transformation required for the display thereof.

Abstract: The invention relates to a system, device, and method for using radar signals to measure the distance (h) to a surface from said device, the device comprising a transmitter and a transmitting antenna for transmitting radar signals, and a receiver and a receiving antenna for receiving a radar signal. The device may also comprise a first additional reflecting object separate from the receiving antenna, which additional reflector is designed so as to introduce a first predetermined alteration in radar signals upon reflection, with the device being equipped with means to differ between received signals with and without said predetermined alteration. The first predetermined alteration introduced by the first separate reflector can be, for example, a modulation shift or a shift in the polarization of the signal. In a typical embodiment the additional reflector is located close to the radar unit creating a double transition from radar unit to the surface.

Abstract: A scanning panel for use in a microwave imaging system captures a microwave image of a target using two complementary arrays of antenna elements. Each of the antenna elements in a first array is capable of being programmed with a respective phase delay to direct a transmit beam of microwave illumination toward the target in a transmit beam pattern, and each of the antenna elements in a second array is capable of receiving reflected microwave illumination reflected from the target in a receive beam in a receive beam pattern complementary to the transmit beam pattern. The microwave image of the target is formed at an intersection between the transmit beam and the receive beam.

Abstract: A system for identification and tracking of microwave responsive tags, the system comprising, a microwave responsive tag having a passive modulating element to uniquely backscatter directed microwave beams, a microwave base station for directing microwave beams in room sized areas, and a tag tracking system receiving input from the microwave base station, the tag tracking system storing state records of position and informational content of the microwave tag.

Abstract: A system and method for ascertaining the range of a noise-jamming target. The system includes a receiver; a data processor coupled to the receiver; and software adapted for execution by the data processor for computing rage to a target transmitter using first and second assumptions with respect to the output power level thereof and interpolating with respect to an error term calculated with respect thereto. The method includes the steps of: making assumptions with respect to an output power level of a transmitter located at the target; measuring a level of power received form the transmitter by a receiver at first and second distances relative to the transmitter; calculating an error term with respect to the assumptions; interpolating with respect to the error term to make a range calculation; and outputting the range calculation when the error term reaches a predetermined threshold.

Abstract: A system containing a navigational marker, the navigational marker having the ability to reflect radar in such a manner that the navigational marker is identified. In one embodiment, a polarized radar-reflective material is affixed to the navigational marker. A radar signal is reflected by the polarized radar-reflective material, causing the reflected radar signal to be polarized. The reflected radar signal is received and the navigational marker is identified. The radar system contains a detector/decoder capable of distinguishing the type of navigational marker based on the reflected radar signal. The detector/decoder relays information about the navigational marker to a display. In another embodiment, a navigational marker contains a radio responder. When a radar signal illuminates the navigational marker, the radio responder transmits a signal containing encoded data. A receiver detects the signal from the responder and decodes the encoded data. The decoded data is relayed to a display.

Abstract: There is provided an electrically powered augmenter device that has a silicon window. The silicon window emits the infrared radiation from the augmenter in a specific waveband, to attract heat seeking missles. Moreover, the augmenter may be mounted on the fuselage of an unpowered aerial towed target or other airborne vehicle.

Abstract: In a method and device for the encoding/decoding of power distribution at outputs of a system, a distribution encoder includes an element that receives a useful input signal and a piece of distribution information, and that superposes the piece of distribution information received on the input signal. The piece of information is used for the subsequent distribution of the total power of the input signal at an output or outputs of the system. A distribution decoder includes one or more inputs that receive an encoded signal or an encoded signal divided into several signals including the useful signal and the piece of distribution information. Further, one or more outputs are connected to the outputs of the system to which the useful signal is transmitted by distributing the total power received according to the piece of distribution information. The method and device enable, for example, fast, low-power switching of the outputs of a high-power system and the programming of a system with variable power outputs.

Abstract: The invention is a radar decoy which electronically simulates objects by generating radar detectable signals over the entire microwave frequency range. The simulator includes a series of tuned, spaced diode networks for generating carrier suppressed doppler side bands. Each diode network operates at a single, different frequency. The diode networks are enclosed by a corner reflector which modulates the amplitude and the phase of an impinging radar signal. The diode networks are controlled by a switching network which turns the diodes on and off at a desire frequency to produce a doppler frequency shift and thereby simulate moving objects.

Abstract: A method and apparatus are provided for sensing two-dimensional identification marks provided on a substrate or embedded within a substrate below a surface of the substrate. Micropower impulse radar is used to transmit a high risetime, short duration pulse to a focussed radar target area of the substrate having the two dimensional identification marks. The method further includes the steps of listening for radar echoes returned from the identification marks during a short listening period window occurring a predetermined time after transmission of the radar pulse. If radar echoes are detected, an image processing step is carried out. If no radar echoes are detected, the method further includes sequentially transmitting further high risetime, short duration pulses, and listening for radar echoes from each of said further pulses after different elapsed times for each of the further pulses until radar echoes are detected.

Abstract: A reflector circuit is provided which responds to illuminating radiation with corresponding output radiation of increased magnitude relative to the illuminating radiation, while also providing a frequency selective limiting characteristic. The circuit comprises an antenna for receiving the illuminating radiation and emitting the corresponding output radiation, a delay line providing a frequency selective limiting and signal storage characteristic and an amplifier assembly. The antenna provides an input signal upon receipt of the illuminating radiation, a portion of which is amplified, frequency selectively filtered and then stored for a period after which it is emitted as the output radiation from the circuit. Switches are incorporated and are operable to counteract spontaneous oscillation within the circuit.

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: A pulse-echo ranging system includes an improved target and a ranging device which emits pulses of electromagnetic radiation toward the target and receives pulses reflected from the target. The target is provided with a modulating mechanism for modulating the reflected pulses in a predetermined manner. The modulating mechanism allows the ranging device to distinguish pulses truly reflected from the target from noise and pulses reflected from objects other than the target. More specifically, the modulating mechanism may include a reflector which reflects the pulses at plural distances from the ranging device. The reflector may include a single reflective surface coupled to an oscillating vibrator, or plural reflective surfaces spaced at different locations from the ranging device.

Abstract: A modulated retroreflection system for secure two-way communication and identification includes a transceiver at a first location and a transponder at a second location. The transponder receiving, modulating, and reflecting the signal back to the transceiver includes a retroreflector having a at least one reflective surface coated with an electro-responsive material. The electro-responsive material modulating the reflection coefficient of the reflective surface thereby modulating signals reflected by the surface. The transponder further includes a modulator electrically connected to the electro-responsive material for applying a modulated bias voltage thereby modulating the refractive index and consequently the electrical phase, and/or amplitude of the reflected signal.

Abstract: The invention is an identification friend or foe system for an aircraft providing identification information when illuminated by an incident radar signal. In detail, the system includes at least a portion of the aircraft's surface incorporating magnetic material for absorption of at portion of the incident radar signal with the remainder reflected and scattered back in the direction of the incident radar signal. A electromagnetic coil assembly) is positioned behind the aircraft skin and is used to impress a biasing field on a portion of the aircraft's surface incorporating the magnetic material such that the biasing field modulates the reflected and scattered signal. A system is coupled to the coil assembly to modulate the biasing field such that the reflected and scattered signal from the portion of the aircraft's surface incorporating the magnetic material is modulated with an encoded signal incorporating the identification information.

Abstract: A post launch identification friend or foe fire control system for a munition has an identification and ranging interrogation unit for mounting on a munition. The interrogation unit transmits an interrogation unit which detects and verifies an incoming identification code from a remote transponder unit in reply to the interrogation code. The range of the remote transponder is determined and a decision signal is provided to the fire control circuit of the munition to enable it to avoid a friendly target; a transponder unit receives the rf carrier signal containing an incoming interrogation code from an interrogation unit on board a munition, validates the incoming interrogation code, and extracts a timing signal from it. An identification code is synchronously generated with the incoming interrogation code using the timing signal. The synchronized identification code is then transmitted back to the interrogation unit on board the munition to confirm the identification of the transponder unit and its range.

Abstract: A system and method for providing interactive multimedia services to subscriber premises utilizing wireless distribution within the subscriber premise. The service is provided via a communications link delivering to the subscriber premises broad band digital information including video and audio from a plurality of information providers and control signals in a multiplexed form. This multiplexed signal is then separated and processed on premise and distributed in a two-way fashion using frequency hopping code division multiple access (CDMA) spread spectrum using radio frequency signals preferably at UHF. Upstream control signals from the user installation are communicated from the individual user terminals in the same wireless manner.

Abstract: A synchronous communication targeting system for use in battle. The present invention includes a transceiver having a stabilizing oscillator, a synchronous amplifier and an omnidirectional receiver, all in electrical communication with each other. A remotely located beacon is attached to a blackbody radiation source and has an amplitude modulator in electrical communication with a optical source. The beacon's amplitude modulator is set so that the optical source transmits radiation frequency at approximately the same or lower amplitude than that of the blackbody radiation source to which the beacon is attached. The receiver from the transceiver is adapted to receive frequencies approximately at or below blackbody radiation signals and sends such signals to the synchronous amplifier. The synchronous amplifier then rectifies and amplifies those signals which correspond to the predetermined frequency to therefore identify whether the blackbody radiation source is friendly or not.

Abstract: A radar highway motor vehicle guidance apparatus for guiding a land vehicle along a roadway using a forward looking, lateral position sensing, monopulse tracking radar guidance apparatus which transmits radar pulses forward of the vehicle. The pulses are reflected back to the vehicle by a stripe distributed along the roadway. The stripe is a frequency selective surface which generates retro-reflective grating lobes at an operating frequency of the tracking radar. Operating the radar at two frequencies allows the radar to look at regions spaced at two different distances from the front of the vehicle. Highway related information may be encoded in the frequency selective surface by variations in the shape or dimensions of the frequency selective stripe morphology in order to modulate the reflected signal with highway information which is then also detected at the radar receiver. Target discrimination is enhanced by using pseudo random codes and matching antenna polarization with stripe polarization.

Abstract: A microwave radar reflector includes three, substantially planar networks whose reflectivity or transmissivity may be controlled. The three networks are arranged as a trihedron with an open angle. An additional network, whose reflectivity or transmissivity may be separately controlled, is located at said open angle of the trihedron. With the additional network controlled to be transmissive and the other networks having their characteristic modulated between reflective and transmissive, the reflector will return a modulated message when the reflector is illuminated.

Abstract: A method to confuse a police radar by moving a multiplicity of radar reflector antennas in the field of view of the radar. The moving radar reflector antennas present continuously changing doppler velocities to the police radar. The radar reflectors can be any of several reflective antennas such as dipoles, Yagies, horns, etc. The continuously changing doppler velocities are generated by mounting the radar reflector antennas on a moving disk. The moving disk is driven by an electric motor or by the wind. The radar reflector antennas can also be mounted on the rim or in the tread of a vehicle's tires.

Abstract: An antenna reflector, which can reflect incoming radio waves, is formed as a corner of a cube by orthogonally connecting three reflectors which can reflect incoming radio waves. The reflectors are formed from semiconductor layers, conductive sheets scattered on one surface of the semiconductor layers, insulator films formed on both sides of the semiconductor layers, conductor films provided on the opposite surface of each of the insulator films, and switching elements that are formed on the semiconductor layers and which connect the conductive sheets. As a result, if direct current voltage is applied between the resistor films, the reflectors reflect radio waves while radio waves are absorbed when no direct current voltage is applied, and thus, the reflected radio wave is modulated by the application and non-application of the direct current voltage.