Abstract: A method for detecting a concealed material in a target comprising a body and the concealed material, the method comprising: emitting radio frequency (RF) energy toward a direction of the target, capturing a signal corresponding to a scattered RF energy reflected from the target, measuring a first mean signal level in a first frequency band of the signal, measuring a second mean signal level in a second frequency band of the signal, and detecting the concealed material when the difference between the first mean signal level and the second mean signal level is above a threshold.

Abstract: A system and method for processing radar returns to identify returns from man-made objects. In one embodiment, a plurality of radar returns is used to form a corresponding plurality of resonance maps, which are combined using an ordered statistic to form a processed resonance map. A discriminant is calculated as (a) the fourth power of the ratio of (i) the power in a first rectangle about each pixel to (ii) the power in a region outside the first rectangle and inside a second, larger rectangle, or (b) zero if the ratio is less than 1. Other processing operations including thresholding operations to suppress noise and clutter are used to improve the signal to noise ratio for detecting man-made objects.

Abstract: A method for detecting a concealed object in a target comprising a body and the concealed object, the method including emitting, by an emitter, radio frequency (RF) energy toward a direction of the target, receiving, by a receiver, a scattered RF energy reflected from the target, generating, by the receiver, a signal corresponding to the received scattered RF energy, comparing, by a processor, the signal with a plurality of stored RF scattering signatures, each of the RF scattering signatures being associated with an object of interest, and detecting, by the processor, the concealed object when the signal matches one of plurality of RF scattering signatures.

Abstract: A system and method for high-availability inverse synthetic aperture radar (ISAR). In one embodiment a set of quadratic phase vectors, each corresponding to a different acceleration, is multiplied, one at a time, in a Hadamard product, with a 3-dimensional data cube, and a fast Fourier transform (FFT) is taken of the result, to form a 2-dimensional array. The two-dimensional array is made sparse by setting to zero elements that fall below a threshold based on a coherency metric, and the sparse arrays are stacked to form a sparse 3-dimensional image. Projections of the sparse 3-dimensional image are formed for presentation to an operator or an image exploitation system.

Abstract: A synthetic aperture radar imaging method that combines each radar return pulse with a sinusoid to reduce the radar return pulses to a baseband frequency and deskew each radar return pulse. It includes determining a maximum likelihood estimate (MLE) of residual motion parameters for a dominant scatterer on the ground relative to the airborne radar and correcting for errors in inertial navigation system measurements based on the MLE residual motion parameters. It includes convolving each radar return pulse with its corresponding radar transmission pulse to generate a range compressed image for each radar return pulse and generating a sub-band range profile image for each radar return pulse and its corresponding radar transmission pulse based on the corresponding range compressed image that has been corrected for residual motion. Performing bandwidth extrapolation on each sub-band and subsequently combining the three bands to produce an enhanced resolution image without grating lobes.

Abstract: In certain embodiments, a subterranean imaging apparatus comprises at least two receive channels configured on a land-based vehicle and a synthetic aperture radar (SAR) system. The at least two receive channels are operable to generate electrical signals according to electromagnetic radiation reflected from a subterranean target below a ground surface. The SAR system is operable to receive the electrical signals from the at least two receive channels, generate raw images from the received electrical signals, generate a weighting according to phase statistics of pixels in the raw images, and combine the raw images using the weighting to generate a refined image of the subterranean target.

Abstract: A subterranean radar array system and method for imaging a subterranean target area. In one example, the subterranean radar array includes a plurality of radar chains disposed in a plurality of underground columns, each radar chain including a plurality of radar units forming the plurality of radar chains and at least one processor coupled to a corresponding at least one of the plurality of radar chains and configured to generate an image of a subterranean target area from signals received from the at least one radar chain.

Abstract: A system comprises a radar transmitter configured to generate a radar signal at a predetermined frequency and a radar receiver configured to receive a reflected signal produced by a reflection of the radar signal. The system further includes a radar antenna system configured to transmit the radar signal into a subterranean region and to receive the reflected signal from the subterranean region. A control system is used for controlling a dwell time of the radar antenna system, and a processor is adapted to generate an image of at least a portion of the subterranean region based at least in part on the reflected signal.

Abstract: System and method for calculating three dimensional residual motion errors of a moving platform with respect to a point of interest by receiving a radar signal from the point of interest (302); forming a radar image including a plurality of scatterers (304); using an MLE method to obtain range, radial velocity and acceleration of the moving platform for a first peak scatterer in the radar image (306); correcting a location of the first peak scatterer with respect to a scene center of the point of interest (312); updating the obtained radial acceleration responsive to the corrected location (314); and updating the obtained radial velocity of the moving platform responsive to the updated radial acceleration (316).

Abstract: A method of generating an image comprises accessing a dataset gathered from a sensor system and generating, from the dataset, a first image including a plurality of image elements. The method further includes generating a training image by combining the dataset with known sensor responses and generating a weighting factor by correcting the training image in view of the known sensor responses. The method further includes applying the weighting factor to one of the plurality of image elements to form a weighted image element.

Abstract: System and method for calculating three dimensional residual motion errors of a moving platform with respect to a point of interest by receiving a radar signal from the point of interest (302); forming a radar image including a plurality of scatterers (304); using an MLE method to obtain range, radial velocity and acceleration of the moving platform for a first peak scatterer in the radar image (306); correcting a location of the first peak scatterer with respect to a scene center of the point of interest (312); updating the obtained radial acceleration responsive to the corrected location (314); and updating the obtained radial velocity of the moving platform responsive to the updated radial acceleration (316).

Abstract: A subterranean radar array system and method for imaging a subterranean target area. In one example, the subterranean radar array includes a plurality of radar chains disposed in a plurality of underground columns, each radar chain including a plurality of radar units forming the plurality of radar chains and at least one processor coupled to a corresponding at least one of the plurality of radar chains and configured to generate an image of a subterranean target area from signals received from the at least one radar chain.

Abstract: A system comprises a radar transmitter configured to generate a radar signal at a predetermined frequency and a radar receiver configured to receive a reflected signal produced by a reflection of the radar signal. The system further includes a radar antenna system configured to transmit the radar signal into a subterranean region and to receive the reflected signal from the subterranean region. A control system is used for controlling a dwell time of the radar antenna system, and a processor is adapted to generate an image of at least a portion of the subterranean region based at least in part on the reflected signal.

Abstract: In certain embodiments, a subterranean imaging apparatus comprises at least two receive channels configured on a land-based vehicle and a synthetic aperture radar (SAR) system. The at least two receive channels are operable to generate electrical signals according to electromagnetic radiation reflected from a subterranean target below a ground surface. The SAR system is operable to receive the electrical signals from the at least two receive channels, generate raw images from the received electrical signals, generate a weighting according to phase statistics of pixels in the raw images, and combine the raw images using the weighting to generate a refined image of the subterranean target.

Abstract: According to one embodiment, a synthetic aperture radar includes a back projection processor that is configured to receive multiple return signals from the radar as the radar is moved with respect to an object, wherein the return signals are representative of electro-magnetic radiation reflected from the object. The back projection processor generates a dynamic image of one or more internal features of the object from the return signals by varying a squint angle of the plurality of return signals in which the squint angle varied by modifying a back projection filter. Once generated, the back projection processor displays the dynamic image on a display.

Abstract: According to one embodiment, a synthetic aperture radar includes a back projection processor that is configured to receive multiple return signals from the radar as the radar is moved with respect to an object, wherein the return signals are representative of electro-magnetic radiation reflected from the object. The back projection processor generates a dynamic image of one or more internal features of the object from the return signals by varying a squint angle of the plurality of return signals in which the squint angle varied by modifying a back projection filter. Once generated, the back projection processor displays the dynamic image on a display.

Abstract: According to one embodiment, a radar includes multiple antenna elements coupled to an image processing application. The antenna elements have a differing vertical spatial separation relative to one another and are configured to transmit a radio-frequency signal toward a stationary object and receive multiple reflected radio-frequency signals from one or more internal features of the building. The image processing application receives the reflected radio-frequency signals as the antenna elements are moved horizontally with respect to the stationary object. From these reflected radio-frequency signals, the image processing application generates imagery of the stationary object according to phase variations in the plurality of received radio-frequency signals. The imagery depicting vertical characteristics of the one or more internal features of the building.

Abstract: According to one embodiment, a synthetic aperture radar (SAR) processing system includes multiple radar receivers and a corresponding multiple location determining devices communicating with a SAR processor. The SAR processor receives return envelopes from each radar receiver indicative of electro-magnetic energy reflected from a target of interest. The SAR processor also receives, from multiple location determining devices that are each configured with each radar receiver, a location signal representing the position of its associated radar receiver, and generates imagery of the target according to the received envelopes and the position associated with each received envelope.

Abstract: According to one embodiment, an image generating device includes an image former coupled to a radar that transmits and receives electro-magnetic radiation at multiple frequencies. The image former generates an image using information received from the radar, adjusts the image according to a material characteristic of the object, and combines the image with other images received at differing frequencies to form a resulting image.

Abstract: According to one embodiment, a synthetic aperture radar includes multiple antenna elements coupled to an image processing application. The antenna elements have a differing vertical spatial separation relative to one another and are configured to transmit a radio-frequency signal toward a stationary object and receive multiple reflected radio-frequency signals from one or more internal features of the building. The image processing application receives the reflected radio-frequency signals as the antenna elements are moved horizontally with respect to the stationary object. From these reflected radio-frequency signals, the image processing application generates imagery of the stationary object according to phase variations in the plurality of received radio-frequency signals. The imagery depicting vertical characteristics of the one or more internal features of the building.