Abstract: A microwave imaging system captures a microwave image of a target and minimizes noise in the microwave image using phase differentiation. A reflector antenna array is provided including a plurality of antenna elements for reflecting microwave radiation towards the target and for reflecting microwave radiation reflected from the target towards a microwave receiver. A processor programs the antenna elements with respective first phase shifts to capture a first microwave image of the target, and programs the antenna elements with respective second phase shifts to capture a second microwave image of the target. The first phase shift of each antenna element is 180 degrees different than the second phase shift for that antenna element. The processor minimizes noise from a combination of the first microwave image and the second microwave image.

Abstract: A test device for a frequency modulated continuous wave (FMCW) radar is provided. The test device has a central control unit for monitoring the FMCW radar. When the FMCW radar transmits a frequency modulated continuous signal to search for a target, the central control unit of the test device in present invention will simulate the motion of the target according to a plurality of setting parameters and generate an echo signal to the FMCW radar. The present invention also includes a first digital signal synthesizer and a transmitting unit. The first digital signal synthesizer is coupled to the central control unit for generating and transmitting an intermediate-frequency signal to the transmitting unit according to the settings in the central control unit and a reference clock. The transmitting unit generates the echo signal according to the intermediate-frequency signal.

Abstract: A method transforms an image from polar coordinates into Cartesian coordinates. Therefore, the target image in Cartesian coordinates is subdivided into triangles defined by the vertices given in Cartesian coordinates. The respective polar coordinates are coded into attributes and these attributes are attached to each vertex. The attributes of any coordinates within the triangle are calculated by performing a bilinear interpolation on a graphics card and the polar coordinates are calculated from these attributes. Finally, the characteristics of the coordinates of the image in polar coordinates are transferred to the corresponding coordinates of the target image given in Cartesian coordinates. A method also consistently displays single ore multiple radar scan images with additional geographical data in one display plane. These methods may be performed by a computer program and implemented in a radar scan converter.

Abstract: Sensing characteristics of an object includes transmitting a stepped-frequency radar through an object and detecting, with multiple receiving structures, deflected portions of the radar signal. The detected portions are processed to generate processed data including information associated with amplitudes and phases of the deflected portions, and with the locations of the receiving structures at which the deflected portions were detected. The processed data is analyzed to determine information corresponding to dielectric properties particular positions within the object.

Abstract: A system, according to various aspects of the present invention, provides a presentation to a hazard display. The system includes a memory having surveillance data and a processor. The processor updates an image in accordance with the surveillance data to provide an updated image. The processor also prepares a presentation in accordance with the updated image. The processor further provides the presentation to the hazard display. At least one of updating, preparing, and providing utilize a first scan mode for a hazardous region of the presentation and a second scan mode for a nonhazardous region of the presentation.

Abstract: One embodiment of the present invention provides several electromagnetic radiation reflectors within a volume that contains solid portions subject to movement relative to one another. At least a portion of the reflectors are positioned beneath one or more of the solid portions and move in response to movement of at least some of the solid portions. The volume is irradiated with electromagnetic radiation having one or more frequencies in a range from one kHz through one THz, and a reflection is detected of at least a portion of the electromagnetic radiation from each of the reflectors in response to this irradiation. Movement among the solid objects is evaluated from the reflection of each of the reflectors, which includes determining a spatial orientation of each one of the reflectors as a function of at least one of polarization selectivity and frequency selectivity.

Abstract: A method of characterizing a maximum height of a storm cell for an aircraft is provided. First reflectivity data formed from a first scan of a storm cell by a radar is received and a first centroid of the storm cell is identified. Second reflectivity data formed from a second scan of the storm cell by the radar is received and a second centroid of the storm cell is identified. A scan axis for a third scan of the storm cell based on the first centroid and the second centroid is determined. Third reflectivity data formed from the third scan of the storm cell by the radar at a first time is received. The third reflectivity data is sampled to form pixel data that includes a reflectivity indicator determined for each pixel formed from the third reflectivity data. A maximum height of the storm cell is determined by processing the pixel data.

Abstract: Traffic collision and avoidance systems and methods for a host aircraft. The system receives traffic information from one or more target aircraft, determines threat levels of target aircraft associated with the received traffic information, generates one or more objects based on the determined threat levels and a pre-defined threat level, and displays the generated one or more objects that are associated with threat levels within the pre-defined threat level. A first indicator that indicates lateral position relative to the host aircraft and a second indicator that indicates vertical direction of travel of the associated target aircraft are also displayed.

Abstract: A moving radar (405) generates a synthetic aperture image from an incomplete sequence of periodic pulse returns. The incomplete sequence of periodic pulse returns has one or more missing pulses. The radar converts the incomplete sequence of pulse returns into a digital stream. A computer (403) processes the digital stream by computing an along track Fourier transform (402), a range compression (408), an azimuth deskew (410) and an image restoration and auto focus (412). The image restoration and autofocus (412) utilizes a low order autofocus (501), a gap interpolation using a Burg algorithm (503), and a high order autofocus (505) for generating an interpolated sequence. The interpolated sequence contains a complete sequence of periodic pulse returns with uniform spacing for generating the synthetic aperture image. The image restoration and autofocus (412) computes a linear prediction coefficients estimate using the Burg Algorithm (606).

Abstract: A microwave imaging system uses microwave radiation provided by a microwave source to image targets. The system includes an array of antenna elements that are capable of being programmed with a respective transmission coefficient to direct the microwave illumination from the microwave source toward a position on the target. The antenna elements are further capable of being programmed with a respective additional transmission coefficient to receive reflected microwave illumination reflected from the position on the target and direct the reflected microwave illumination towards a microwave receiver. A processor is operable to measure an intensity of the reflected microwave illumination to determine a value of a pixel within an image of the target. Multiple beams can be directed towards the target to obtain corresponding pixel values for use by the processor in constructing the image.

Abstract: A method and apparatus to remove human features utilizing at least one transmitter transmitting a signal between 200 MHz and 1 THz, the signal having at least one characteristic of elliptical polarization, and at least one receiver receiving the reflection of the signal from the transmitter. A plurality of such receivers and transmitters are arranged together in an array which is in turn mounted to a scanner, allowing the array to be passed adjacent to the surface of the item being imaged while the transmitter is transmitting electromagnetic radiation. The array is passed adjacent to the surface of the item, such as a human being, that is being imaged. The portions of the received signals wherein the polarity of the characteristic has been reversed and those portions of the received signal wherein the polarity of the characteristic has not been reversed are identified. An image of the item from those portions of the received signal wherein the polarity of the characteristic was reversed is then created.

Abstract: A radar apparatus transmits a pulse signal including pulses having at least two different pulselengths in a specific transmit pulse pattern and receives a returning echo signal through a single antenna. A tuning voltage setting timing generator generates a timing of setting a tuning voltage according to a combination of transmission pulselengths and a tuning processor performs tuning operation in a manner suited to a current transmission pulselength based on the tuning voltage setting timing. The radar apparatus may include a tuning voltage alteration decider for deciding whether or not to alter the tuning voltage based on a combination of alternate pulselengths before altering the pulselength of the pulse signal generated by a transmitter and the tuning processor alters the tuning voltage based on the result of decision made by the tuning voltage alteration decider.

Abstract: A microwave imaging system suppresses sidelobes in a microwave image captured using a sparse antenna array using an illumination system that operates in two different illumination modes. The antenna array including subarrays of antenna elements arranged in a sparse geometry to form complementary subarray patterns. The illumination system operates in a first mode to transmit microwave illumination to both of the complementary subarray patterns of the antenna array and receive reflected microwave illumination from both of the complementary subarray patterns of the antenna array to produce a first receive signal. The illumination system further operates in a second mode to transmit microwave illumination to a first one of the complementary subarray patterns of the antenna array and receive reflected microwave illumination from a second one of the complementary subarray patterns of the antenna array to produce a second receive signal.

Abstract: An imaging system can include an antenna apparatus configured to transmit toward and receive from a subject in a subject position, millimeter-wave electromagnetic radiation. A subject may include a person and any object or objects with the person. A controller can include a transceiver configured to operate the antenna apparatus and produce an output representative of the received radiation, and a processor adapted to produce from the transceiver output, image data representative of an image of the subject. At least a first portion of an image signal representative of radiation received by an antenna apparatus may be used to produce first image data representative of a first image of at least a portion of the subject. Second image data representative of a second image having resolution that is different than that of the first image may be produced from at least a second portion of the image signal.

Abstract: Described herein is an implementation of the IRAMS processing based upon a multi-delay-resolution framework applied to SAR image data measured at different aspect angles. The power of this new embodiment of IRAMS is that it produces a good separation of immediate response scatterer and delayed response scatterer data for the case of anisotropic scattering events, i.e., those in which the scattering intensity depends upon the aspect angle. Two sources of delayed response scattering include multiple reflection scattering events and delayed responses arising from the physical material composition of the scatterer. That is, this multi-delay-resolution IRAMS processing separates immediate response and delayed response scattering for cases in which there exist delayed response scattering data in the original SAR image data at some aspect angles, but the intensity of these delayed response scattering data is weak or non-existent at different aspect angles.

Abstract: One embodiment of the present invention includes scanning a target with electromagnetic radiation including one or more frequencies in a range of about 200 MHz to about 1 THz; establishing a point cloud representation of the surface of the target from the scan; and performing one or more curve-fitting operations as a function of at least a portion of the points of the point cloud representation to represent at least a portion of the surface of the target.

Abstract: A concealed weapons and contraband detection system combining metal detection equipment with millimeter wave imaging equipment. The preferred millimeter wave imaging equipment includes at least one millimeter wave frequency scanning antenna for collecting frequency dependent beams of millimeter wave radiation from a narrow one-dimensional field of view. The collected radiation is amplified at the collected frequencies and the amplified signals are separated into frequency dependent bins with a tapped-delay beam-former. These bins are then sampled 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 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. In preferred embodiments the millimeter wave imager is combined with an active eddy current type metal detector to provide a hybrid system providing important advantages over prior art security systems.

Abstract: A method for reducing angular blur in radar pictures achieved in range bin based detection systems includes measuring a variable S(x, y) such as amplitude or power as a function of an angle x and a distance y. An expression: corrected angular position=angular position+angle correction is determined in each range bin for a plurality of angular values x. The term “angle correction” includes derivative(s) of first or higher order of the variable S(x). The variable measured at the angular position “angular position” is moved to the variable in the angular position “corrected angular position”, and the moved variable and the variable in “corrected angular position” are processed by adding or maximizing the values.

Abstract: A non-destructive detection method and system enables detecting a moisture patch located inside a building wall or the like. A transmitter generates a series of ultra-wideband pulses while an ultra-wideband antenna unit, preferably in the form of an antenna array including a plurality of switchable antenna pairs, directs the pulses toward the building structure so that the pulses are reflected therefrom, and receives the reflected pulses. A receiver processes the reflected pulses received by the antenna unit and produces a corresponding output. A controller controls the operation of the transmitter, receiver and antenna unit, and analyzes the output of the receiver for the presence of moisture inside of the building wall.

Abstract: A system comprises a radar for producing a radar interrogation signal, a transponder for receiving the radar interrogation signal and producing a transponder signal including a first linear frequency modulated pulse having an increasing frequency and a second linear frequency modulated pulse having a decreasing frequency, and a processor for processing the transponder signal to determine a frequency offset between the radar interrogation signal and the transponder signal.

Abstract: Active millimeter-wave imaging systems can include an antenna apparatus configured to transmit toward and receive from a subject in a subject position, electromagnetic radiation. A controller can include a transceiver configured to operate the antenna apparatus and produce an output representative of the received radiation, and a processor adapted to convert the transceiver output into image data representative of an image of the subject. The antenna apparatus may move in a partial or continuous loop around the subject, toward or away from the subject, or in an opposite direction to an associated antenna apparatus. Antenna units in the antenna apparatus may be oriented at different angular positions along an array. Antenna arrays may also be formed of a plurality of array segments, and a group of arrays may be combined to form an antenna apparatus.

Abstract: A vertical situation display (“VSD”) system according to the invention generates a terrain image that represents a profile view of terrain elevation relative to the position of an aircraft traveling above the terrain. The VSD system generates the VSD image such that the terrain image is biased toward the lower elevation region of the VSD screen, thus making efficient use of the available display area. The VSD image is also generated such that it is continuous across the lateral range of the VSD, thus ensuring that terrain is shown in the VSD at all practical times, depending upon the available range and any priority display rules.

Abstract: Methods and apparatus are provided for operating a radar system to provide a thunderstorm image to a pilot. The method comprises using one or more radar scans depending upon the aircraft altitude, a single upward tilted scan at or below a datum level of about 15,000±3000 feet wherein a clutter free storm image may be obtained and two scans above the datum level; a first upward tilting scan to determine, clutter free, a storm head perimeter and a second lower tilting scan for the storm body with ground clutter. The perimeter is used to discard return echoes from the second scan that lie outside the perimeter or an expansion thereof and retain those lying on or within the perimeter. The result is presented to the pilot. Optionally, the thunderstorm image is graded from center to edge so as to indicate weaker echo intensity near the edge.

Abstract: A radar on a moving platform for three dimensional target recognition of a target on a flat or sloping terrain is described. The target is illuminated from a plurality of locations to generate images at many aspect angles. The radar is positioned at a low grazing angle with respect to the target for generating a shadow of the target on the flat or sloping terrain for each aspect angle of the plurality of aspect angles. The radar comprises an analog to digital converter for converting reflections from the target induced by radar illumination into target digital data and for converting reflections induced by the illumination from the flat or sloping terrain into terrain digital data.

Abstract: A surveillance system can include a first sensor apparatus configured to interrogate a subject, including a person and objects carried by the person, with millimeter-wave electromagnetic radiation for imaging the subject. A supplemental source provides additional information about the subject that is relatable to objects potentially carried by the person. Relational information relates the produced image signal and the subject information. The supplemental source may be a second sensor apparatus adapted to detect a given characteristic of an object potentially carried by a person in the subject position. Relational information about whether the person is carrying an object having the given characteristic may then be produced.

Abstract: An imaging system can include an antenna apparatus configured to transmit toward and receive from a subject in a subject position, millimeter-wave electromagnetic radiation. A subject may include a person and any object or objects with the person. A controller can include a transceiver configured to operate the antenna apparatus and produce an output representative of the received radiation, and a processor adapted to produce from the transceiver output, image data representative of an image of the subject. At least a first portion of an image signal representative of radiation received by an antenna apparatus may be used to produce first image data representative of a first image of at least a portion of the subject. Second image data representative of a second image having resolution that is different than that of the first image may be produced from at least a second portion of the image signal.

Abstract: An imaging apparatus has transmitter illuminating a selected surface with a radar beam footprint, and processor for profiling/processing the radar returns so as to derive attitude information in real time about a number of predefined axes associated with the radar which depends upon the relative dispositions of the radar, the selected surface and upon the radar beam footprint characteristics. A plurality of transmit beams image the surface and the processing arrangement has the capability of determining roll, pitch and/or yaw pointing data associated with the radar, such pointing data being determined by derivation of the attitude information and by selective input of terrain elevation data so as to take account of variations in the radar viewing geometry with terrain elevation. This provides a low cost advantage over known radar designs, and retains utility for many applications, for example spaceborne and airborne applications.

Abstract: A millimeter wave imaging system that includes at least one millimeter wave frequency scanning antenna for collecting frequency dependent beams of millimeter wave radiation from a narrow one-dimensional field of view. The collected radiation is amplified at the collected frequencies and the amplified signals are separated into frequency dependent bins with a tapped-delay beam-former. These bins are then sampled 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 across the field of view of the scanning antenna. In a preferred embodiment the antenna is only 4.5 inches in length and constructed from WR-10 waveguide with inclined slots cut in one of the narrow walls at 79 mil spacings. This geometry creates a frequency-scanned antenna spanning a 20 degree vertical field of view over a 75.5–93.5 GHz operational band of the sensor, starting at approximately 1 degree below horizontal at 93.

Abstract: Detailed is radar imaging apparatus including a single transmit antenna and at least one receive antenna, scanning apparatus (e.g. a pantograph) for mechanically scanning the antennas over a surface of interest, position providing apparatus (e.g. a computer driving the pantograph via an X-Y drive and a stepper motor) providing a position signal indicative of the instantaneous position of the transceiver and a control system for operating the transmit antenna in a stepped frequency continuous wave mode. The amplitude and phase components of the receive antenna signal are analysed and the output combined with the position signal as in a synthetic aperture array to provide a radar image signal of the surface and underlying features. The scan is two-dimensional (random or boustrophedral).

Abstract: An inspection system uses microwave radiation to capture a microwave image of a transportable item. The system includes a transmit scanning panel including a transmit array of transmit antenna elements, each being programmable with a respective phase delay to direct a transmit beam of microwave radiation toward a target of the transportable item for transmission of the microwave radiation through the target. The system further includes a receive scanning panel including a receive array of receive antenna elements, each being programmable with a respective phase delay to receive a receive beam of microwave radiation from the target. A processor measures the amplitude and phase of the microwave radiation in the receive beam to determine a relative value of a pixel within the microwave image of the transportable item based on a reference value of the pixel.

Abstract: A surveillance system can include a first sensor apparatus configured to interrogate a subject, including a person and objects carried by the person, with millimeter-wave electromagnetic radiation for imaging the subject. A supplemental source provides additional information about the subject that is relatable to objects potentially carried by the person. Relational information relates the produced image signal and the subject information. The supplemental source may be a second sensor apparatus adapted to detect a given characteristic of an object potentially carried by a person in the subject position. Relational information about whether the person is carrying an object having the given characteristic may then be produced.

Abstract: An image processing system to be mounted to a vehicle includes a radar adapted to measure distance and direction to an object based on reflected electromagnetic waves which are outputted to scan the exterior of the vehicle, an image-taking device such as a camera for obtaining an image, and an image processor for carrying out image processing on a specified image processing area in an image obtained by the image-taking device. The image processor is adapted to determine a center position of the image processing area according to a measurement point of an object detected by the radar and the size of the image processing area according to a beam profile of electromagnetic waves outputted from the radar.

Abstract: Described herein are frequency-domain back-projection processes for forming spotlight synthetic aperture radar (“SAR”) images that are not corrupted by the effects of multiple-bounce ghosting artifacts. These processes give an approximately exact reconstruction of the multiple bounce reflectivity function (MBRF) ƒ(x,y,?). Specifically, the evaluation of ƒ(x,y,?) in they ?=0 plane gives an approximately exact reconstruction of the true object scattering centers which is uncorrupted by multiple-bounce contributions to the phase history data G(?, ?). In addition, the non-zero dependence of ƒ(x,y,?) upon the MB coordinate ? can be used to facilitate the identification of features-interest within the imaged region.

Abstract: A passive millimeter wave imaging system that includes at least one millimeter wave frequency scanning antenna and multiple beam formers collecting narrow beams of millimeter wave radiation from a two-dimensional field of view. The collected radiation is amplified and separated into bins corresponding to various vertical and horizontal beam orientations. In a preferred embodiment the beam formers include one phase processor and 192 frequency processors. Two dimensional images of a target are obtained by the simultaneous detection of signal power within each beam and converting it into pixel intensity level at a rate of 30 frames per second.

Abstract: A FM-CW radar system comprises a frequency modulated continuous wave digital generator that produces both in-phase (I) and quadrature-phase (Q) outputs to orthogonally oriented transmitter antennas. A linearly polarized beam is output from a switched antenna array that allows a variety of I-and-Q pairs of bowtie antennas to be alternately connected to the transmitter and receiver. The receiver inputs I-and-Q signals from another bowtie antenna in the array and mixes these with samples from the transmitter. Such synchronous detection produces I-and-Q beat frequency products that are sampled by dual analog-to-digital converters (ADC's). The digital samples receive four kinds of compensation, including frequency-and-phase, wiring delay, and fast Fourier transform (FFT). The compensated samples are then digitally converted by an FFT-unit into time-domain signals. Such can then be processed conventionally for range information to the target that has returned the FM-CW echo signal.

Abstract: An interrogating system can include an interrogating apparatus configured to transmit toward and receive from a subject in a subject position, millimeter-wave electromagnetic radiation. Such a system can also include a controller configured to operate the interrogating apparatus, and produce data representative of a characteristic of the subject from received radiation. Some embodiments of such an interrogating system may include interrogating apparatus adapted to be mounted to a passenger vehicle or at a vehicle passenger loading zone, to interrogate passengers prior to boarding the vehicle. Such embodiments may include one or more controllers positioned within the vehicle or at the loading zone.

Abstract: A method of displaying areas of turbulent weather is disclosed. Data is processed representative of weather conditions within a predefined area. Weather conditions are displayed on a display. Turbulence is detected within the predefined area. A level of the detected turbulence is detected. First graphical elements are superimposed upon the display of weather conditions when the level of the detected turbulence is less than a predetermined amount. A second graphical element is displayed upon the display of weather conditions when the level of the detected turbulence is more than the predetermined amount.

Abstract: An obstacle penetrating dynamic radar imaging system for the detection, tracking, and imaging of an individual, animal, or object comprising a multiplicity of low power ultra wideband radar units that produce a set of return radar signals from the individual, animal, or object, and a processing system for said set of return radar signals for detection, tracking, and imaging of the individual, animal, or object. The system provides a radar video system for detecting and tracking an individual, animal, or object by producing a set of return radar signals from the individual, animal, or object with a multiplicity of low power ultra wideband radar units, and processing said set of return radar signals for detecting and tracking of the individual, animal, or object.

Abstract: A distance can be measured with high resolution. A frequency controller (7) controls a voltage control oscillator (2) so as to change a signal source frequency f in a range containing two center frequencies f1 and f2 and transmits it as a traveling wave from an antenna (4) to a target (5). A reflected wave reflected by the target (5) and the traveling wave interfere each other and form a standing wave. A power detector (6) detects power corresponding to the amplitude of the standing wave and performs Fourier transform based on the two center frequencies f1 and f2 in Fourier transform means (11, 12), respectively, thereby calculating radar image functions P1(x), P2(x). The distance d to the target (5) satisfies the conditions that the phase difference of the two radar image functions zero-crosses and the amplitude of the radar image functions becomes maximum. The zero cross point of the phase difference is a zero cross point of a linear function and can be identified with high resolution.

Abstract: A subject may be interrogated with electromagnetic radiation for producing image data representative of an image of the subject. First and second image data, produced based on reflectivity in first and second frequency ranges, may be related. In some examples, image data for one picture element may be produced based at least in part on reflectivity of the radiation at a depth selected based at least in part on a depth of another picture element. In some examples, plural images may be produced based on reflectivity at different depths. In some examples, a value of reflectivity may be determined for an intermediate depth between two adjacent depths of image data based at least in part on reflectivity of the radiation for a plurality of spaced-apart depths.

Abstract: Methods, systems, and computer program products for storing turbulence radar return data into a three-dimensional buffer. The method involves modeling the radar signal scattering properties of space surrounding the radar/aircraft. Presented turbulent wind variance measurements are compared to predictions of the measurement using the modeled scattering properties, thereby producing more accurate turbulence information for storage into the three-dimensional buffer.

Abstract: Unpredictable response variations of the output value signals from radiometer or receiver channels due to noise are minimized when composing a millimeter wave image. The image is composed from composition signals which are each related to the corresponding output value signals from the channels. Some composition signals are weighted by a weighting factor which is different from a weighting factor used for weighting other composition signals. Preferably, the reciprocal of the standard deviation of variations of the output value signals from each channel is used as the weighting factor for deriving the composition signals from the output value signals from that channel. The intensity of each pixel of the image is composed by adding the weighted composition signals associated with that pixel.

Abstract: In an exemplary embodiment, an augmented reality system for traffic control combines data from a plurality of sensors to display, in real time, information about traffic control objects, such as airplanes. The sensors collect data, such as infrared, ultraviolet, and acoustic data. The collected data is weather-independent due to the combination of different sensors. The traffic control objects and their associated data are then displayed visually to the controller regardless of external viewing conditions. The system also responds to the controller's physical gestures or voice commands to select a particular traffic control object for close-up observation or to open a communication channel with the particular traffic control object.

Abstract: An imaging system can include an antenna apparatus configured to transmit toward and receive from a subject in a subject position, millimeter-wave electromagnetic radiation. A subject may include a person and any object or objects with the person. A controller can include a transceiver configured to operate the antenna apparatus and produce an output representative of the received radiation, and a processor adapted to produce from the transceiver output, image data representative of an image of the subject. At least a first portion of an image signal representative of radiation received by an antenna apparatus may be used to produce first image data representative of a first image of at least a portion of the subject. Second image data representative of a second image having resolution that is different than that of the first image may be produced from at least a second portion of the image signal.

Abstract: Provided is a bistatic and multistatic system for detecting and identifying a target in close proximity to an orbiting satellite. An electromagnetic fence is established to surround the satellite, using a ground-based communication uplink from a gateway antenna. A contact or breach of the electromagnetic fence by the target is detected by the satellite, or at other sensor locations, and an exact position, range and ISAR image of the target is calculated using scattered RF energy from the fence. Identification data is transmitted to satellite system monitors, whereby the data is used to decide on a corrective course of action.

Abstract: Active millimeter-wave imaging systems can include an antenna apparatus configured to transmit toward and receive from a subject in a subject position, electromagnetic radiation. A controller can include a transceiver configured to operate the antenna apparatus and produce an output representative of the received radiation, and a processor adapted to convert the transceiver output into image data representative of an image of the subject. The antenna apparatus may move in a partial or continuous loop around the subject, toward or away from the subject, or in an opposite direction to an associated antenna apparatus. Antenna units in the antenna apparatus may be oriented at different angular positions along an array. Antenna arrays may also be formed of a plurality of array segments, and a group of arrays may be combined to form an antenna apparatus.

Abstract: A subject may be interrogated with electromagnetic radiation for producing image data representative of an image of the subject. First and second image data, produced based on reflectivity in first and second frequency ranges, may be related. In some examples, image data for one picture element may be produced based at least in part on reflectivity of the radiation at a depth selected based at least in part on a depth of another picture element. In some examples, plural images may be produced based on reflectivity at different depths. In some examples, a value of reflectivity may be determined for an intermediate depth between two adjacent depths of image data based at least in part on reflectivity of the radiation for a plurality of spaced-apart depths.

Abstract: An airborne weather radar system that detects potentially hazardous weather conditions associated with storms and includes a radar display featuring visual indications of these conditions. The radar display includes a vertical situation display having iconal representations and symbolic icons indicative hazardous weather conditions and aviation hazards along the aircraft's flight path not otherwise immediately apparent or shown on standard weather radar displays. The system includes processes for detecting and predicting hazardous weather conditions such as overshooting thunderstorm tops and vaulted thunderstorm energy and serious hazards such as turbulence and hail.

Abstract: An aircraft weather radar system is disclosed. The system comprises a radar antenna, aircraft sensors, and a database. The system also comprises a processing device receiving information from the radar antenna and from the aircraft sensors and able to retrieve information from the database. Further, the system comprises a cockpit display coupled to the processing device. The processing device is programmed to determine storm system hazards and to display the storm system hazards on the display using an iconal representation or textual representation.

Abstract: A radar receiver on a moving platform images a moving target and non-moving clutter using a single SAR array. The radar receiver converts the radar returns into digital radar returns and motion compensates the digital radar returns with respect to a reference, then applies further phase compensation to obtain an autofocused synthetic aperture image. A plurality of moving target pixels descriptive of the moving target are detected within the autofocused synthetic aperture image. The plurality of moving target pixels are transformed from the autofocused image to the time domain. The time domain moving target data is focused by iteratively applying a phase compensation to the time domain moving target data.