Abstract: Circularly-polarized antennas and their methods of use for active holographic imaging through barriers. The antennas are dielectrically loaded to optimally match the dielectric constant of the barrier through which images are to be produced. The dielectric loading helps to remove barrier-front surface reflections and to couple electromagnetic energy into the barrier.

Abstract: The present invention relates to a device for detecting objects. The device comprises at least one microwave-frequency transmitter and one microwave-frequency receiver. The receiver makes a relative rotary movement about the transmitter, a signal being transmitted toward an individual for several positions of the receiver on the circle of relative rotation, the signals reflected by points of an object and received by the receiver at the positions being supplied to processing means in order to form a radar image. The receiver and the transmitter can be installed on a disk with a very low moment of inertia. The invention applies notably for the detection of weapons or explosives carried by persons.

Abstract: Proposed is a technique for implementing data communication and distance measurement even in a case where data communication and distance measurement share the physical layer. A wireless communication apparatus includes a radio unit and a distance measuring unit. The radio unit performs communication using a frame that includes at least a data period for transferring data and a beacon period for transmitting a beacon. The distance measuring unit utilizes the beacon period to measure the distance from the wireless communication apparatus to a target object whose distance is to be measured.

Abstract: Embodiments of the disclosed technology comprise a ground penetrating radio device and methods of use for obtaining greater resolution. This is achieved by measuring the composition/reflection off a homogeneous material (e.g., metal plate), determining coefficients to correct the measured/reflection in order to make the measurements look like an idealized reference signal, and then using these coefficients in a digital filter to correct measurements/a reflection off a heterogeneous material, such as a road surface. In this manner, the composition of the heterogeneous material is determined with greater accuracy.

Abstract: A millimeter wave imaging apparatus and method capable of identifying the presence of relatively thin dielectric materials is disclosed. The method involves taking a plurality of millimeter wave images of a scene at different frequencies and analyzing the images at different frequencies to look for frequency dependent effects in the scene. Relatively thin dielectric materials can lead to interference effects which can be detected. In one embodiment the imaging apparatus comprises a millimeter wave imager (2) connected to a processor (16) and at least one variable frequency illumination source (22a . . . d, 24a . . . d). The or each illumination source sweeps the illumination frequency across a reasonably wide bandwidth and the imager captures radiation returned from the scene at a number of different illuminating frequencies.

Abstract: According to one embodiment, a method comprises receiving sensor data generated by one or more sensors in response to sensing a structure. The sensor data is filtered to identify edge data and reverberation data each describing the same structural feature of the structure. Image data for a filtered image of the structure is generated from the edge data, but not from the reverberation data.

Abstract: A forward-looking radar system adapted to detect and identify buried or near surface objects from a moving ground vehicle has been developed. The system incorporates a radar detection system and in one embodiment is mounted on a ground vehicle. The system is adapted to differentiate common roadway clutter from objects of interest.

Abstract: A radar imaging system for capturing an image of an object within an area of interest through at least one visual impairment. The radar imaging system comprises at least one radar array. The radar array includes a plurality of transmitter elements and a plurality of receiver elements for receiving a plurality of coded return signals from an object through the at least one visual impairment.

Abstract: Methods to quantify the amount of radial platform motion of a portable sensor are described. In an exemplary embodiment, the method uses the frequency domain phase data in the range bin corresponding to a large stationary object. A correction factor is computed and applied back into the time domain samples prior to processing by Doppler filters used to measure motion in the scene.

Abstract: A surveillance system is disclosed. In some embodiments, the surveillance system may include at least one controller configured to receive information data from at least one upstream information source and to control operation of at least one controllable downstream information source based, at least in part, on the information data. A surveillance method also is disclosed. In some embodiments, the method may include analyzing screening data, obtaining information data, and reanalyzing the screening data based, at least in part, on the obtained information data.

Abstract: A device for the investigation of an object uses a microwave transmitter, a microwave receiver, a control device and a contrast medium. The microwave transmitter and the microwave receiver are controlled by the control device. In one embodiment, the following steps maybe implemented: introduction of the contrast medium into the object under investigation; transmission of a microwave signal into the object under investigation by the microwave transmitter; scattering of the microwave signal by the object under investigation and by the contrast medium; and/or reception of the scattered microwave signal by the microwave receiver.

Abstract: A device includes a compressible conductive element including a first end and a second end, and an adjustment element coupled to the compressible conductive element, the adjustment element configured to adjust the compressible conductive element to a state of compression between an uncompressed mode and a compressed mode. The compressible conductive element is configured to couple to a source of electrical current at the first end and to radiate electromagnetic energy from the second end.

Abstract: Sensing moving entities includes transmitting a stepped-frequency radar signal including multiple frequencies through a wall from a first side of the wall to a second side of the wall. Portions of the radar signal that are reflected by entities located beyond the second side of the wall are detected. The reflected portions are processed to generate processed data including information associated with frequency shifts between the transmitted signal and the detected signal. The processed data is analyzed to determine if reflected portions are associated with moving entities.

Abstract: A radar device is described, in particular a hand-held short-range radar for determining the location of objects enclosed in a medium, including at least one radar sensor, which generates a first, high-frequency detection signal for penetrating a medium to be tested in such a way that information about an object enclosed in the medium can be obtained by measuring and analyzing the reflected detection signal of the radar sensor. At least one additional sensor is provided for generating at least one additional, second detection signal for obtaining information about the object enclosed in the medium. The method on which this radar instrument is based is also described.

Abstract: A method and apparatus is devised for detecting objects of interest in which frequency-scanned RF in the HF region of the electromagnetic spectrum is projected out across a given area and returns are detected and converted into image data in which phase, amplitude, range and frequency associated with the incoming data is correlated with frequency-dependent range templates to determine the existence of, the range of and the direction of the objects of interest.

Abstract: A millimeter wave imaging system. The system includes one or more millimeter wave frequency scanning antenna for collecting frequency dependent beams of millimeter wave radiation from a narrow one-dimensional field of view and millimeter wave amplifier components for amplifying the millimeter wave radiation collected by each antenna. The system includes a beam-former that separates the amplified radiation to produce frequency dependent signals corresponding to the frequency dependent beams. The beam-former includes delay lines, a millimeter wave lens, and an array of millimeter wave power detectors for detecting the power in each frequency dependent beam. A sampling circuit reads out the frequency dependent signals to produce a one-dimensional image of the antenna field of view. A two dimensional image of a target may be obtained by moving the target (or having the target move) across the field of view of the scanning antenna or by moving the antenna in order to scan its line of focus over the target.

Abstract: Embodiments of the disclosed technology comprise an air-launched antenna system with interference-rejection technology that operates in analog hardware as well as by way of a digital filtering technique. Using an inline analog hardware filter combined with a digital filter, to determine transversal (and/or recursive) coefficients, in a calibration phase, a measurement system may be configured to remove interference and the effects (such as a delay or temperature variation) which result from use of an analog filter. In this manner, the resulting measurements of a composition of road surface are more accurate and useful.

Abstract: Embodiments of the disclosed technology comprise a ground penetrating radio device and methods of use for obtaining greater resolution. This is achieved by measuring the composition/reflection off a homogeneous material (e.g., metal plate), determining coefficients to correct the measured/reflection in order to make the measurements look like an idealized reference signal, and then using these coefficients in a digital filter to correct measurements/a reflection off a heterogeneous material, such as a road surface. In this manner, the composition of the heterogeneous material is determined with greater accuracy.

Abstract: An image processor includes an optical processor and a microwave processor. The optical processor is configured to extract optical image information from optical image data provided by a sensor, the optical image data representing an optical image of an object. The microwave image processor is configured to produce microwave image data representing a microwave image of the object in response to the extracted optical image information and microwave measurements provided by a microwave imager based on illuminating the object with microwave radiation.

Abstract: An active millimeter wave imaging system and method. The system includes a spatially distributed broadband millimeter-wave illuminating source for illuminating a field of view and a millimeter-wave imaging receiver for imaging the field of view. The subject area to be imaged is illuminated simultaneously from many different angles by the distributed source. Reflections from the subjected area are then collected and used to form images. These images in preferred embodiments are compared with passive images made without the millimeter wave illumination from the millimeter wave source. The spatially distributed illumination source in preferred embodiments includes a broadband millimeter-wave noise generator producing millimeter wave radiation at frequencies at which the passive receiver is sensitive and a large reflector. In preferred embodiments the reflector has the shape of a section of an ellipse defining two foci.

Abstract: Electrical properties of concealed dielectric objects, such as the dielectric permittivity, can be deduced from incident, reflected, and transmitted electromagnetic waves in an imaging system. In a confocal arrangement a horn illuminates a reflect array and the reflect array is configured to focus the radiation at an element in the scan volume. The reflections are in turn refocused by a reflect array at the horn aperture. The reflect array is electronically configured to scan the focal point throughout the scan volume in a systematic way. Knowledge of the horn pattern and the scan strategy allows the system to compute the geometry associated with each volume element. Amplitude and phase variations between the object and the surrounding volume and the computed geometry are used to estimate the relative permittivity and thus facilitate categorization of the object using a database of material relative permittivities.

Abstract: A standoff range, sense-through-obstruction radar system is capable of detecting micro-Doppler, or life form signatures, and movements through obstructions at stand-off ranges and displaying the target information over a live video feed of the area under surveillance. The sense-through-obstruction radar system comprises an antenna assembly that includes a horn antenna and a reflector configured to reflect radio frequency (RF) energy to/from the horn antenna. An antenna pointing assembly supports the antenna assembly. The antenna pointing assembly is configured to move the antenna assembly to point the antenna assembly toward an obstruction. A sensor assembly is mounted to the antenna assembly so that the sensor assembly is aligned with the RF beam formed from the RF energy reflected from the reflector to the horn antenna. The sensor assembly is configured to detect the location of the obstruction and to provide information to assist pointing of the antenna assembly toward the obstruction.

Abstract: An antenna array includes at least one transmit array comprising a plurality of metamaterial elements. The antenna array further includes at least one near-field stimulator for inputting electromagnetic signal to the transmit array so that a sub-wavelength target is illuminated with an electromagnetic wave.

Abstract: A system and method of mapping underground utilities and other subsurface objects involves one or more of acquiring utility location data using a number of different detectors and sensors, processing the multiple detector/sensor output data to produce mapping data, storing the mapping data in a database, and providing access to and use of the stored mapping data by subscribing users on a usage fee basis.

Abstract: A system or method of creating a map of voids in the ground based on a scattered electromagnetic signal includes traversing a receiver/probe in a near field above a target area; generating a signal from a signal transmitter, the signal having a predetermined wavelength ?; receiving a scattered signal with the receiver/probe, the scattered signal including indications of subsurface variations via reflection of the generated signal; and detecting evanescent components of the scattered signal to provide a predetermined resolution. The method includes the use of an electrically small antenna for resolution of subwavelength features. The metamaterial-based antenna is on the order of meters and has an efficient transmit/receive capability. The ESA is 1/10 of the length of the equivalent dipole length, and may be scaled down to 1/10,000. Such an antenna may include phase sensitive current injection in the metamaterial resonant structures for loss-compensation.

Abstract: A variable range millimeter wave method and system is disclosed. In a particular embodiment, the system includes a primary mirror having an aperture to reflect millimeter wave energy to a secondary mirror, where the secondary mirror is disposed in front of the primary mirror and adapted to redirect the millimeter wave energy to a millimeter wave sensor/detector of a millimeter wave camera. The millimeter wave camera is configured to process the millimeter wave energy to visually detect concealed objects hidden on a target and an operating frequency of the millimeter wave camera is between 225 GHz and 275 GHz. In addition, the system includes a laser rangefinder, GPS and altimeter to determine a location of the target and to optimize a focus of the millimeter wave camera. A video monitor displays millimeter wave imagery and video images spatially and temporally relative to the millimeter wave imagery to aid targeting.

Abstract: A method of identification of a living body is provided. The method comprises steps of detecting an electromagnetic wave in a frequency band ranging from 300 GHz to 30 THz transmitted from the living body, extracting plural kinds of information from the detected electromagnetic wave, and deriving therefrom information on the living body and information inherent to the living body, and comparing the information on the living body and the information inherent to the living body with preliminarily memorized information. This method identifies an individual living body with improved real-time detectableness and higher security to prevent illegal pretension.

Abstract: The present invention is a method and apparatus that provides detection, characterization, and intuitive dissemination of targets. This disclosure combines improvements to ultra-wideband (UWB) sensing and machine target characterization with a means to convey data in a format that is quickly and readily understood by practitioners of the technology. The invention is well suited for Situational Awareness (SA) support in areas that are occluded by rain, fog, dust, darkness, distance, foliage, building walls, and any material that can be penetrated by ultra-wideband RF signals. Sense Through The Wall (STTW) performance parameters including target range, stand-off distance, and probability of detection are improved herein by combining a dynamically positioned sliding windowing function with orthogonal feature vectors that include but are not limited to time amplitude decay, spectral composition, and propagation time position in the return signal data.

Abstract: A system and method to detect uncrushable metallic pieces hidden inside a mineral load directly inside a transport device to a primary crusher includes a directionally adjustable radar having at least one device with electromagnetic wave emitter/receiver antennas, a portal through which the transport device passes, a spectral generator/analyzer connected to the antenna devices that generates the electromagnetic waves and analyzes the echoes of the electromagnetic waves that interact with the mineral load, and a computational device that includes a digital signal processor connected to the spectral generator/analyzer.

Abstract: A radar fall detector system. The radar fall detector system includes transmitter and receiver antennae and a signal processor that processes a reflected signal. Doppler analysis of the reflected signal determines a subject's activity and condition, and its distance to a floor.

Abstract: A method for designing low signature array antennas using a calculation method. The method proposes a way of improving antenna and signature performance of array antennas. According to the method electromagnetic antenna and signature characteristics are specified, an iterative optimizing method is performed to design the antenna to fulfil the specified characteristics, the iterative method is interrupted when a design fulfils the specified characteristics, and the specified characteristics are readjusted in an iterative optimizing method to follow if the specified characteristics not are fulfilled.

Abstract: In a method for operating a radar system and a radar system for performing the method, in particular a microwave radar system for applications in or on motor vehicles, in which at least one target object and at least one possible concealing object are detected using radar technology, it is provided in particular that a detection is made of whether a concealment situation of the at least one target object by the at least one concealing object exists, and in the case of a detected concealment situation a loss of the target object is not automatically assumed.

Abstract: An imaging system operative in a frequency range starting from X band and including the terahertz region has a receiving antenna having a spheroidal reflector. One or more arrays of detectors disposed at the focus adjacent to the reflector of the receiving antenna provides for imaging targets within a range of a few meters around the second focus of the spheroidal reflector. Images of targets such as of concealed objects under clothing are generated and displayed as is known in the art. A method for manufacturing reflectors of receiving antennae given a detection range and a focal range is provided.

Abstract: A sensing system is provided that includes a transceiver. The transceiver includes a transmitter chain that transmits a double-sideband signal having first and second frequency components, and a receiving chain that receives the double-sideband signal after it is reflected by a target. The system further includes a baseband circuit for extracting information content from the received double-sideband signal. A separation between a first frequency of the first frequency component and a second frequency of the second frequency component causes a spike in a signal response generated by one sideband of the received double-sideband signal to substantially overlap a null point of a signal response generated by the other sideband of the received double-sideband signal.

Abstract: A system includes a radar unit configured to provide raw data from scanning an exterior of a structure; and a signal processing and imaging module configured to: process the raw data into markers of interior locations of the structure; and display an image of interior structural features based on the markers. A method includes: scanning a building structure from the exterior of the structure using a radar unit to provide raw data; processing the raw data into markers of interior locations of the structure; estimating locations of interior structural features of the structure from the markers; and displaying an image of the interior structural features.

Abstract: An apparatus and method for detecting and locating hidden objects employs a symmetrical array of five directional antennas, including a central transmit antenna and a pair of receive antennas at each side of the transmit antenna, respectively. All of the antennas are pointed in the same general direction toward an object field of interest. The transmit antenna radiates a beam of high-frequency electromagnetic energy, and the receive antennas receive high-frequency electromagnetic energy returned by hidden objects. Each pair of receive antennas has an associated phase detector, the output of which represents the phase difference between receive antenna signals corresponding to the received electromagnetic energy. A circuit determines when the outputs of the phase detectors represent predetermined phase differences and operates indicator devices.

Abstract: The apparatus of the present invention consists of a MicroPower Radar (MPR), a data acquisition (DAQ) element and a PDA. The radar sends a short, low-amplitude signal of radio-frequency (RF) energy toward the target scene. This signal reflects from the target and is received as a Doppler change. RF has the advantages of penetrating clothing while operating at one fiftieth the power of a cellular or cordless phone. This Doppler change in signal amplitude is filtered, amplified and presented to the DAQ. The DAQ converts the analog Doppler signal into a digital bit-stream and passed to the processor. Proprietary software analysis is performed to further filter and to make a Live/Dead determination. The radar antenna is located at the back of the device and should be pointed toward the victim, the display facing the operator.

Abstract: A detection system comprises a transmitter unit, a receiver, and a processor. The transmitter unit is capable of transmitting a first collimated beam having a first frequency and a second collimated beam having a second frequency into a ground, wherein the first collimated beam and the second collimated beam overlap in the ground. The receiver is capable of monitoring for a response radio frequency signal having a frequency equal to a difference between the first frequency and the second frequency. The response radio frequency signal is generated by an object having non-linear conductive characteristics in response to receiving the first collimated beam and the second collimated beam. The processor is capable of controlling an operation of the transmitter unit and the receiver. The processor is connected to the transmitter unit and the receiver. The object is detected when the response radio frequency signal is detected by the receiver.

Abstract: The invention relates to a system and method for detecting, locating and identifying objects located above ground or below ground in an area of interest, comprising an airborne vehicle which circumscribes the area of interest and which includes a built-in radar having an antenna with a respective transmitter and receiver, signal-processing means, data-storage means and graphical interface means. According to the invention, the area of interest has been pre-referenced and the radar is a heterodyne ground penetration radar (GPR). The signal transmitted by the antenna generates a beam that illuminates a strip of earth, consisting of a sinusoidal electromagnetic signal having a frequency that is varied in precise pre-determined progressive steps.

Abstract: A method of near-field imaging of a region of interest includes emitting an input of near-field electromagnetic radiofrequency energy from a near-field source device into the region of interest, detecting a mechanical wave response generated in the region of interest in response to the near-field electromagnetic energy input using a detector device, and providing image data representing an image of the region of interest based on the mechanical wave response.

Abstract: An inspection system that can detect contraband items concealed on, in or beneath an individual's clothing. The system employs millimeter wave radiation to detect contraband items. The system is described in connection with a check point security system that includes temperature controlled walls to enhance imaging of contraband items. Also, a millimeter wave camera is used in conjunction with a visible light camera that forms images. To address privacy concerns of displaying images of people made with millimeter wave cameras that effectively “see through” clothes, the millimeter wave images are not displayed directly. Rather, computer processing produces indications of suspicious items from the underlying raw millimeter wave images. The indications of suspicious items are overlaid on the image formed by the visible light camera.

Abstract: The invention relates to a method for operating an electrical device which during operation emits electromagnetic radiation at least temporarily, and to a method for operating a locating device for identifying objects. The method for operating an electrical device is characterized in that the presence of an external radiation source or radio communication service is detected. The invention also relates to an electrical device, especially a locating device comprising at least one UWB sensor, which device is operated according to the method of the invention.

Abstract: A system includes a plurality of radar units configured to provide scan data to a network; a signal processing and imaging module connected to the network and configured to receive the scan data, identify a target, and determine a type of the target based on a radar profile of the target; and a display unit in communication with the signal processing and imaging module and configured to provide a tracking display of the target position and type. A method includes scanning an inhabitable area using a plurality of radar detector units to produce scan data; processing the scan data to construct a digitized representation of a target in the inhabitable area; using recovered information of the target to differentiate between a live person, an animal or an object as the target type; and displaying the target type and position on an image display.

Abstract: A method and apparatus for sensing a target through a wall or obstruction by a Moving Target Indicator (MTI) radar sensor. In an exemplary embodiment, a series of radar pulses are transmitted at frequencies less than about 5 GHz. Radar return signals are received at a plurality of receive antenna array subapertures. The radar return signals are processed by a digital beamformer to form multiple beams. Target detection processing detects moving and stationary targets through a plurality of parallel target detection signal processing paths.

Abstract: Methods to quantify the amount of radial platform motion of a portable sensor are described. In an exemplary embodiment, the method uses the frequency domain phase data in the range bin corresponding to a large stationary object. A correction factor is computed and applied back into the time domain samples prior to processing by Doppler filters used to measure motion in the scene.

Abstract: A system supporting data retrieval from a plurality of wireless sensor nodes is defined. The system includes the plurality of wireless sensor nodes and a data retrieval device. The plurality of wireless sensor nodes include a transceiver receiving a first signal and transmitting a second signal. The second signal includes a sensed datum or an encoded statistic based on the sensed datum identified at the plurality of wireless sensor nodes. The data retrieval device includes a plurality of antennas transmitting the first signal toward the plurality of wireless sensor nodes and receiving the second signal from the plurality of wireless sensor nodes, and a processor coupled to receive the received second signal from the plurality of antennas, the processor defining a virtual receive signal from the received second signal for the plurality of antennas and processing the defined virtual receive signal to determine the identified sensed datum.

Abstract: The invention relates to a waveguide (24) for focusing electromagnetic energy on an area of interest, said waveguide (24) comprising outer walls forming a channel with a width (w) and a height (h) for the propagation of the electromagnetic waves. In order to be able to focus the EM waves on an area of interest, i.e. the chest of a patient (20), so that influences which other moving objects in the environment have on the waves, are shielded away, the channel is provided with a first opening and a second opening wherein said walls are non-metal hollow walls filled with an electrically conductive liquid. The waveguide (24) can be used for example with a computed tomography system (12) CT with a rotating gantry (16) and a patient table (18). The waveguide (24) will not produce artefacts in the CT image by scattering the X-ray, like a metal wall would do it. Nevertheless the conductive liquid makes the construction work as a waveguide for EM waves.

Abstract: The invention relates to a method for detection of motion of the surface of an object by means of a detection device, the object being stationary during a detection process, and situated in a space on the opposite side of a wall in relation to the detection device, and having a relative dielectric constant ?r greater than 1.1. The method comprises steps of transmitting radar signals and receiving radar signals reflected by the object, and if a motion has been detected, in addition visualising the motion in a three-dimensional combined radar model and data model. The invention also relates to a detection device for carrying out the method.

Abstract: The present invention includes methods and apparatuses for imaging material properties in natural-fiber-containing materials. In particular, the images can provide quantified measures of localized moisture content. Embodiments of the invention utilize an array of antennas and at least one transceiver to collect amplitude and phase data from radiation interacting with the natural-fiber-containing materials. The antennas and the transceivers are configured to transmit and receive electromagnetic radiation at one or more frequencies, which are between 50 MHz and 1 THz. A conveyance system passes the natural-fiber-containing materials through a field of view of the array of antennas. A computing device is configured to apply a synthetic imaging algorithm to construct a three-dimensional image of the natural-fiber-containing materials that provides a quantified measure of localized moisture content. The image and the quantified measure are both based on the amplitude data, the phase data, or both.

Abstract: An electromagnetic interrogation system and methods for analyzing a target in a test bed are disclosed. A forced resonating antenna unit has a transmit element and a receive element both mounted on a platform movable over the test bed. An interrogation signal source generates a continuous stepped-frequency radio frequency (RF) signal. A plurality of receiver channels are connected to the receive element, and ratios of the scattered continuous stepped-frequency RF signal on a first one of the receiver channels and on a second one of the receiver channels each relative to a reference one of the receiver channels is derived as a measurement for each frequency step. A triggering module linked to the receiver channels generates a positional data value corresponding to a set of measurements for one or more stepped frequency sweeps. An analysis module generates test bed analysis results based upon multiple sets of measurements over time and the corresponding positional data values.