Automatic Target Detection Patents (Class 342/90)
  • Patent number: 7504986
    Abstract: A blind spot sensor system detects and/or classifies objects in a defined monitoring region of a motor vehicle. The blind spot sensor system contains a first device for emitting a first radar beam, and a second device for emitting a second radar beam. The radial visual range of the first radar beam (beam I) inclines counter to a direction of travel of the motor vehicle and the radial visual range of the second radar beam (beam II) is oriented in an substantially vertical manner in relation to the direction of travel such that the visual range of the radar beams (I and II) at least partially overlap and cover, substantially, the monitoring region. At least the first radar beam (beam I) can be actuated in a CW modulation mode and in a FMCW modulation mode. The blind spot sensor is used in vehicles, for example for assisting in lane changing.
    Type: Grant
    Filed: April 18, 2005
    Date of Patent: March 17, 2009
    Assignee: Continental Automotive GmbH
    Inventors: Martin Brandt, Matthias Töns
  • Patent number: 7498968
    Abstract: High resolution SAR images of a target scene at near video rates can be produced by using overlapped, but nevertheless, full-size synthetic apertures. The SAR images, which respectively correspond to the apertures, can be analyzed in sequence to permit detection of movement in the target scene.
    Type: Grant
    Filed: February 13, 2007
    Date of Patent: March 3, 2009
    Assignee: Sandia Corporation
    Inventors: Timothy P. Bielek, Douglas G. Thompson, Bruce C. Walker
  • Publication number: 20090040096
    Abstract: Apparatus and method for real-time determination of radar cross sections is disclosed using interleaved gridding. Radar cross section calculations are amenable to an implementation on parallel processors wherein the shooting window is subdivided into smaller areal units that are assigned to the parallel processors in an alternating fashion, such that the calculations performed by a single processor are not localized to a single area of the shooting window. As further disclosed, the shooting and bouncing ray technique for calculating radar cross sections is implemented using the apparatus and method disclosed herein.
    Type: Application
    Filed: August 9, 2007
    Publication date: February 12, 2009
    Inventors: Chul J. Lee, Sean T. Price
  • Publication number: 20090009380
    Abstract: The invention relates to a radar system which comprises: (a) at least two transmitting units for simultaneously, and in synchronization transmitting electromagnetic radiation in distinct frequencies f1, f2, f3 . . . towards a space of interest; and (b) at least one receiving unit tuned to a frequency of nf1+mf2+qf3 . . . , wherein n, m, q . . . being integers not equal to zero, for receiving a non-linear response of said radiation from objects located within the said space of interest, and wherein the system is characterized in that said transmitted pulses are narrow pulses having duration in the range of between about 1 nanoseconds and about 100 nanoseconds.
    Type: Application
    Filed: January 16, 2008
    Publication date: January 8, 2009
    Applicant: Rafael-Armament Development Authority Ltd.
    Inventors: Itzhak Schnitzer, Avner Rosenberg, Alon Deutsch
  • Publication number: 20090002224
    Abstract: A synthetic aperture radar acquires an image of one or more objects and identifies them as targets. The objects are located in the proximity of clutter within the image such of trees, or a tree line. The radar acquires a SAR image having pixels descriptive of the clutter and the object(s). Regions having object pixels are identified within the synthetic aperture image using an object identification (algorithm), where the object identification (algorithm) utilizes one or more historically known target characteristics and one or more measured characteristic to obtain an output. Boundaries are identified for the one or more objects within the output using an object isolation, such as, for example, a Watershed transform. Clutter pixels are identified external to the one or more objects. The clutter pixels are suppressed from the synthetic aperture image thereby generating a clutter reduced image containing the one or more objects.
    Type: Application
    Filed: September 22, 2005
    Publication date: January 1, 2009
    Inventors: Nader Khatib, Albert Ezekiel
  • Patent number: 7460056
    Abstract: The invention discloses a radar system (100) for the detection of low RCS-objects (110, 140, 150, 160, 190) such as forest fires, said system comprising a first plurality of stations (120) for transmitting radar energy, said stations having mechanically fixed antennas (220), and a second plurality of receive stations (130) for receiving reflections of radar energy transmitted from the transmit stations, said stations having mechanically fixed antennas (220). The antennas (220) of said transmit and receive stations have a main beam (221) which is essentially parallel to the ground, and at least a sub-set of the receive stations is equipped with means for recording a first and a second received signal, and means for subtracting one of said signals from the other of said signals. Said transmit and receive stations are arranged to function within the frequency range of 10-100 MHz.
    Type: Grant
    Filed: November 30, 2004
    Date of Patent: December 2, 2008
    Assignee: Telefonaktiebolaget L M Ericsso (Publ)
    Inventors: Conrado Rivas, Patrik Rivas, Anders Hook
  • Patent number: 7450068
    Abstract: A system and method for using a phased array antenna to concurrently receive an RF signal transmitted by a remote transmitter, to determine the angular location of the remote transmitter using the transmitted signal, and to use that angular location to direct a transmit antenna to transmit information in the direction of the transmitter is disclosed.
    Type: Grant
    Filed: November 20, 2006
    Date of Patent: November 11, 2008
    Assignee: The Boeing Company
    Inventors: Ming Chen, Mark A. Curry, Kenneth G. Voyce
  • Patent number: 7450052
    Abstract: Method and apparatus for detecting objects. In one embodiment, a person entering a secured zone is illuminated with low-power polarized radio waves. Differently polarized waves which are reflected back from the person are collected. Concealed weapons are detected by measuring various parameters of the reflected signals and then calculating various selected differences between them. These differences create patterns when plotted as a function of time. Preferably a trained neural network pattern recognition program is then used to evaluate these patterns and autonomously render a decision on the presence of a weapon. An interrupted continuous wave system may be employed. Multiple units may be used to detect various azimuthal angles and to improve accuracy.
    Type: Grant
    Filed: May 12, 2006
    Date of Patent: November 11, 2008
    Assignee: The MacAleese Companies, Inc.
    Inventors: Jerry Hausner, Jonathan M. West
  • Patent number: 7414570
    Abstract: An adaptive broadcast radar system for tracking targets is disclosed. The radar system includes a transmitter having sub-apertures and a receiver having sub-apertures. The transmitter sub-apertures generate and code a signal waveform. The signal waveform is coded with data about the transmitter, including the degrees of freedom. The receiver receives signals that may include direct path signals and scattered signals correlating to the signal waveforms from the transmitter. The receiver includes a signal processor that regenerates a transmit beam for the coded data, delay, and doppler information from the received signals. The signal processor data quads encapsulates the information.
    Type: Grant
    Filed: May 23, 2006
    Date of Patent: August 19, 2008
    Assignee: Lockheed Martin Corporation
    Inventor: Robert D. Budic
  • Patent number: 7411543
    Abstract: A sensor suite determines location and velocity information relating to a missile threat, which is converted to missile or rocket state estimates. The state estimates are transformed into time-invariant dynamic parameters, unique for each missile type. Estimated rocket dynamic parameters are computed for each target type being considered, and compared with a reference set of rocket parameters representing different target types. The estimated rocket parameters are compared with the reference parameters in a maximum-likelihood sense, and combined using fuzzy logic to identify the rocket type and the likelihood. The identified rocket type and likelihood is used to aid in determining the future location of the missile so countermeasure can be applied.
    Type: Grant
    Filed: August 13, 2004
    Date of Patent: August 12, 2008
    Assignee: Lockheed Martin Corporation
    Inventor: Jeffrey B. Boka
  • Patent number: 7411539
    Abstract: A method for passively detecting the presence of radar signal emitters, in which an ESM unit receives radar signals with a number of antennas, each antenna covering a sector of the surrounding terrain. In order to conserve bandwidth, a technique is used, in which receiving channel is slit into a number of sub-bands. Each sub-band is converted to an IF channel. The individual IF channels are combined into a common IF channel in an adder. This process is repeated once more in order to bring the signals down to baseband, where they are digitized and processed to find the direction to and the identity of the emitter source. A number of ESM units are connected to a control center. In the control center the position of the radar emitter is determined by triangulation. In addition, the identity of the emitter is determined by comparison with known emitter signatures stored in a database.
    Type: Grant
    Filed: November 3, 2003
    Date of Patent: August 12, 2008
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventor: Per Atle Valand
  • Publication number: 20080169967
    Abstract: Method and apparatus to track a contact using a sensor in a two-dimensional radar system, determine a closest point of approach (CPA) for the contact, determine a time to closest point of approach (TCPA) for the contact, and estimate an altitude for the contact from the closest point of approach (CPA) and a cross line of sight distance during the time to closest point of approach (TCPA).
    Type: Application
    Filed: October 30, 2006
    Publication date: July 17, 2008
    Inventors: Thomas E. Wood, Robert S. Ager, Richard B. Fleury, Gregory D. Heuer
  • Publication number: 20080129581
    Abstract: The system and method for standoff detection of human carried explosives (HCE) automatically detects HCE (112) up to a range of (200) meters and within seconds alerts an operator to HCE (112) threats. The system (100) has radar only, or both radar and video sensors, a multi-sensor processor (102), an operator console (120), handheld displays (122), and a wideband wireless communications link. The processor (102) receives radar and video feeds and automatically tracks and detects all humans (110) in the field of view. Track data continuously cues the narrow beam radar (118) to a subject of interest (110), (112) the radar (106), (108) repeatedly interrogating cued objects (110), (112), producing a multi-polarity radar range profile for each interrogation event. Range profiles and associated features are automatically fused over time until sufficient evidence is accrued to support a threat/non-threat declaration hypothesis.
    Type: Application
    Filed: October 11, 2005
    Publication date: June 5, 2008
    Inventors: Robert J. Douglass, John D. Gorman, Thomas J. Burns
  • Patent number: 7382312
    Abstract: Disclosed is a Syntactic Landmine Detector. The syntactic landmine detector processes a received signal from a ground penetrating RADAR which contains at least one spatial sequence, the spatial sequence containing relative spatial information locating impedance discontinuities. The spatial sequence is then associated with at least one physical characteristic of a landmine.
    Type: Grant
    Filed: October 12, 2005
    Date of Patent: June 3, 2008
    Assignee: George Mason Intellectual Properties, Inc.
    Inventor: Kenneth J. Hintz
  • Patent number: 7375675
    Abstract: A method and apparatus are disclosed that enable an over-the-horizon-radar (OTHR) system to detect and track multiple target classes simultaneously, where target classes are defined by the speed and acceleration of the tracked objects. The OTHR is tasked in a staring mode, with a bandwidth and waveform repetition frequency that enable detection of Doppler shifts from all target types, with sufficient clutter reduction and range resolution. The backscattered echoes are buffered for each target class and processed independently. The output of an automatic tracking algorithm then preferentially plots target progress on a single digital map for all target classes.
    Type: Grant
    Filed: March 30, 2005
    Date of Patent: May 20, 2008
    Assignee: SRI International
    Inventor: James R. Barnum
  • Patent number: 7375679
    Abstract: This invention relates to state estimation after processing time-delayed measurements with unknown biases that may vary arbitrarily in time within known physical bounds. These biased measurements are obtained from systems characterized by state variables and by multidimensional parameters, for which the latter are also unknown and may vary arbitrarily in time within known physical bounds. If a measurement is time-late, apply the measurements to an out-of-sequence filter using a mean square optimization criterion that accounts for all sources of uncertainty and delay time, to produce estimates of the true states of the system. If the measurement is not time-late, apply the measurements to an in-sequence filter using a mean square optimization criterion that accounts for all sources of uncertainty to produce estimates of the true states of the system. The estimates are applied to one of (a) making a decision, (b) operating a control system, and (c) controlling a process.
    Type: Grant
    Filed: August 16, 2005
    Date of Patent: May 20, 2008
    Assignee: Lockheed Martin Corporation
    Inventors: Purusottam Mookerjee, Frank J. Reifler
  • Publication number: 20080111730
    Abstract: Various embodiments are described herein for a track quality based multi-target tracker and an associated method. The method includes associating a measurement with a track, generating measurement association statistics for the track, generating and updating a track quality value for a track based on a measurement-to-track association likelihood, and updating track lists based on the track quality value and the measurement association statistics of the tracks in these lists. The tracker includes structure for carrying out this method.
    Type: Application
    Filed: June 1, 2007
    Publication date: May 15, 2008
    Inventors: Zhen Ding, Abhijit Sinha, Thia Kirubarajan, Mohamad Farooq
  • Publication number: 20080088498
    Abstract: A target detecting apparatus mounted on a vehicle has an electronically agile radar detecting a beat signal indicating a difference in frequency between transmission and reception signals and producing a time series of N reception data from the beat signal, a determining unit determining search areas placed at different ranges of distance from the vehicle while considering a running state of the vehicle and determining a data length for each search area, an extracting unit extracting (N?M+1) time series of short time data, respectively, having the data length corresponding to M reception data from the N reception data for each search area, a producing unit producing phase information from the short time data for each search area, and a detecting unit determining a target distance and a target bearing from the phase information and detecting a target from the target distance and the target bearing.
    Type: Application
    Filed: October 5, 2007
    Publication date: April 17, 2008
    Applicant: DENSO Corporation
    Inventors: Koichiro Suzuki, Chiharu Yamano, Kazuma Natsume
  • Patent number: 7352321
    Abstract: An entity is subjected to an interrogating signal, and the reflection from the entity is repeatedly sampled to obtain a first set of values each dependent on the intensity of the reflected signal. A logarithmic transformation is applied to the sample values to obtain a second set of values. A set of descriptor values is derived, the set comprising at least a first descriptor value (L) representing the difference between the mean and the median of the second set of values, and a second descriptor value (D) representing the mean of the absolute value of the deviation between each second set value and an average of the second set of values.
    Type: Grant
    Filed: September 22, 2005
    Date of Patent: April 1, 2008
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Wieslaw Jerzy Szajnowski, Miroslaw Bober
  • Patent number: 7345621
    Abstract: A real-time signal processing engine robustly detects, localizes, tracks and classifies ground targets based on radar signals from a multistatic radar system. The system differentiates between different targets based on an optimized cost function, which can include the total returned normalized pulse energy. The local transmitters/receivers can communicate with each other via the transmitted radar signals.
    Type: Grant
    Filed: February 26, 2007
    Date of Patent: March 18, 2008
    Assignee: BBN Technologies Corp.
    Inventors: John M. Bourdelais, Ernest Scott Stickles, William Ray Wright, David Earl Norris, Michael Anthony Tiberio, Gary Dana Butler
  • Patent number: 7339516
    Abstract: A method to present easily understood images that represent targets that are detected through walls or other opaque barriers is disclosed. This method is particularly well suited for sense-through-the-wall radar systems. One of the main challenges of evolving STTW systems is that the practitioners of the technology are generally presented with complicated images to represent the gain adjusted amplitude of signals that are detected by the radar. Interpretation of images from prior art, which can be in the form of the radar speckle, target blob, wiggle plot, and horizontal amplitude intensity displays, shown in FIGS. 1 through 3, requires high levels of skill, focus, and time. Naturally, the foregoing places military and law-enforcement customers of the technology at considerable risk during hostile missions. This invention discloses a method that converts a typical radar signal into an image that is easily understood by a practitioner of STTW technology.
    Type: Grant
    Filed: November 14, 2005
    Date of Patent: March 4, 2008
    Assignee: RealTronics Corporation
    Inventors: Scott Randall Thompson, Bernt Askild Askildsen
  • Patent number: 7333047
    Abstract: An ultra wideband radar system for detecting objects where at least one of the radar system or the object is moving. The radar may be scanned in at least one dimension, which may include angle or range. The system includes a scan combiner that combines scan information in accordance with a trajectory characteristic of a moving object and/or of a moving platform on which the radar resides. Scans may be combined by integration or filtering. A fast calculation method is described wherein the scans are combined into subsets and subsets are shifted in accordance with the trajectory characteristics before further combination. The scan information is combined in accordance with trajectory characteristics to enhance the object signal to noise. Further features are described wherein the scan information is combined according to a family of candidate trajectories and/or object positions.
    Type: Grant
    Filed: October 22, 2005
    Date of Patent: February 19, 2008
    Assignee: Time Domain Corporation
    Inventors: Larry W. Fullerton, James Richards
  • Patent number: 7327307
    Abstract: An adaptive waveform radar system transmits a selected waveform of a family of related waveforms and either phase shifts or bit shifts the radar return signal for correlating with the other waveforms of the family. In some embodiments, phase shifting may be performed to null an unwanted target or clutter, while bit shifting may be performed to enhance a desired target, although the scope of the invention is not limited in this respect. In some embodiments, the bits of the return signal may be either phase shifted or bit shifted to match a bit of each one of the other waveforms of the family prior to correlation.
    Type: Grant
    Filed: July 7, 2005
    Date of Patent: February 5, 2008
    Assignee: Raytheon Company
    Inventors: Vinh Adams, Wesley Dwelly
  • Publication number: 20080012749
    Abstract: A standoff radiation detection and identification system is capable of detecting radiation from remote locations, such as at distances of 100 feet or more. The system can verify radiation associated with vehicles or vessels prior to them entering sensitive areas. The ability to detect radiation at standoff distances enables the interception of the vehicle or vessel for further analysis. The system combines standoff radiation detection with interceptors that can be deployed for further close range analysis of a source of radiation.
    Type: Application
    Filed: January 16, 2007
    Publication date: January 17, 2008
    Applicant: Innovative American Technology, Inc.
    Inventor: David L. FRANK
  • Patent number: 7317416
    Abstract: A system for identifying an individual, including an imaging radar for receiving radar data pertaining to at least a portion of a skeleton of at least one individual, an imaging module for generating at least one skeletal image of the at least one individual based on the radar data, at least one database including a plurality of skeletal data pertaining to a plurality of individuals, an identification module for comparing the at least one skeletal image with the plurality of skeletal data to determine a match.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: January 8, 2008
    Inventors: Leonard Flom, Ophir Almog
  • Publication number: 20070285303
    Abstract: A system and method is presented for detecting and classifying slow-moving and hovering helicopters from a missile's took-down Doppler radar that is compatible with the existing base of Doppler radars. This approach uses definable attributes of a helicopter rotor assembly and its extended Doppler rotor return to differentiate “rotor samples” from other samples (steps 123, 125), extract features such as bandwidth, activity, angle, and shape from the rotor samples (step 127), and classify a potential target as a helicopter or other based on the extracted rotor features and the known attributes of the helicopter rotor assembly (step 129). A target report including a classification target, range, range-rate, and angle of the extended rotor return is suitably passed to a tracking processor (step 121).
    Type: Application
    Filed: June 12, 2006
    Publication date: December 13, 2007
    Inventors: Bernard P. Radza, Joseph Henning, Sunny Ali, John Mincer, Randal Walters
  • Patent number: 7301495
    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).
    Type: Grant
    Filed: January 11, 2006
    Date of Patent: November 27, 2007
    Assignee: Raytheon Company
    Inventors: Theagenis John Abatzoglou, Leo H. Hui, Kwang M. Cho
  • Patent number: 7298314
    Abstract: A system and method for electromagnetic position determination utilizing a calibration process. For calibration, a transmitter is positioned at multiple locations in an area of interest and multiple receivers receive and record signal characteristics from the transmitter to generate a calibration data set. The unknown position of a transmitter may be determined by receiving signals from the transmitter by multiple receivers. A locator data set is generated based on the comparison between two received signal characteristics determined for each receiver. The locator data set is compared with the calibration data set to determine the unknown position. In one embodiment, the signal comparisons are the differences between electric and magnetic field phase. Further embodiments utilize signal amplitude differences. A reciprocal method utilizing a single receiver and multiple transmitter locations is disclosed.
    Type: Grant
    Filed: October 4, 2004
    Date of Patent: November 20, 2007
    Assignee: Q-Track Corporation
    Inventors: Hans Gregory Schantz, David Wesley Langford
  • Patent number: 7295149
    Abstract: A target missile identifier compares radar cross-section (RCS) information about the missile with a set including at least one template of RCS to make determination(s) of at least one of (a) the missile type (solid/liquid propellant), (b) missile main engine cutoff, andor (c) staging state of a multistage missile.
    Type: Grant
    Filed: October 19, 2005
    Date of Patent: November 13, 2007
    Assignee: Lockheed Martin Corporation
    Inventor: David E. Wolf
  • Patent number: 7289060
    Abstract: A radar classifies an unknown target illuminated with a large bandwidth pulse. The large bandwidth pulse may be algorithmically synthesized. The target reflects the large bandwidth pulse to form a return. The return is digitized into digital samples at range bin intervals. A computer extracts unknown range and amplitude pairs descriptive of the unknown target from the digital samples. Some range and amplitude pairs are located within one range bin interval. Principle scatterers are extracted from the unknown range and amplitude pairs using Modified Forward backward linear Prediction to form an unknown feature vector for the target. A plurality of pre-stored, known feature vectors containing known range and amplitude pairs are retrieved from the computer. The known range and amplitude pairs are descriptive of known targets, and are grouped in clusters having least dispersion for each of the known targets.
    Type: Grant
    Filed: May 24, 2006
    Date of Patent: October 30, 2007
    Assignee: Raytheon Company
    Inventors: Theagenis J. Abatzoglou, Raquel E. Maderazo, Jessica E. Swanson, Frederick A. Dominski
  • Patent number: 7277047
    Abstract: This invention relates to sate estimation after processing measurements with unknown biases that may vary arbitrarily in time within known physical bounds. These biased measurements are obtained from systems characterized by state variables and by multidimensional parameters, for which the latter are also known and may vary arbitrarily in time within known physical bounds. The measurements are processed by a filter using a mean square optimization criterion that accounts for random and biased measurement errors, as well as parameters excursions, to produce estimates of the true states of the system. The estimates are applied to one of (a) making a decision, (b) operating a control system, and (c) controlling a process.
    Type: Grant
    Filed: February 6, 2006
    Date of Patent: October 2, 2007
    Assignee: Lockheed Martin Corporation
    Inventors: Purusottam Mookerjee, Frank J. Reifler
  • Patent number: 7277045
    Abstract: A method for obtaining target parameters within an adaptive broadcast radar system. In one embodiment, the method includes: coding information about a signal waveform generated by a transmitter having sub-apertures; receiving a signal at a receiver having sub-apertures corresponding to the sub-apertures of the transmitter, wherein the received signal correlates to the signal waveform; decoding information about the signal waveform from the received signal; and, determining a data quad from the decoded information, wherein the data quad includes degrees of freedom associated with the transmitter.
    Type: Grant
    Filed: May 23, 2006
    Date of Patent: October 2, 2007
    Assignee: Lockheed Martin Corporation
    Inventor: Robert D. Budic
  • Publication number: 20070205937
    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.
    Type: Application
    Filed: March 3, 2006
    Publication date: September 6, 2007
    Applicant: REALTRONICS CORPORATION
    Inventors: Scott Randall Thompson, Bernt A Askildsen, Anthony Gervasi
  • Patent number: 7259714
    Abstract: A method of detecting radar returns and measuring their parameters with or without clutter present and no clutter cancellation employed which includes transmitting at least one pulse; processing the returns surpassing a threshold detected in one range azimuth bin and by processing and separating out the returns based on their different range and azimuth. Another method includes transmission of many pulses and has minimum of one channel return surpassing detected threshold, which is detected in one range Doppler bin. The method also includes processing and thereby separating out the returns based on their different radial velocity and or azimuth and comparing the returns to a database of expected returns and adaptively processing returns that do not correspond to the expected returns. The method identifies the non-corresponding returns as indicative of at least one of clutter, land sea interface, clutter discretes and antenna sidelobe returns each without utilizing clutter cancellation.
    Type: Grant
    Filed: May 1, 2006
    Date of Patent: August 21, 2007
    Inventor: Thomas J. Cataldo
  • Patent number: 7248206
    Abstract: Unknown alignment biases of sensors of a tracking system are estimated by an iterative Kalman filter method. Current measurements are corrected for known alignment errors and previously estimated alignment biases. The filter time reference is updated to produce estimated target state derivative vectors. A Jacobian of the state dynamics equation is determined, which provides for observability into the sensor alignment bias through gravitational and coriolis forces. The target state transition matrix and the target error covariance matrix are propagated. When a new measurement becomes available, the Kalman gain matrix is determined, the state vector and covariance measurements are updated, and sensor alignment biases are estimated. The state vector, covariance measurements, and estimated sensor alignment biases are transformed to an estimated stable space frame for use in tracking the target and updating the next iteration.
    Type: Grant
    Filed: June 10, 2005
    Date of Patent: July 24, 2007
    Assignee: Lockheed Martin Corporation
    Inventors: Jeffrey B. Boka, Peter J. Mavroudakis, Naresh R. Patel
  • Patent number: 7248207
    Abstract: Systems and methods for detecting targets using pulse-compressed radar signals are disclosed. In one application, relatively small targets that are masked by the time-sidelobes of a larger target's return signal can be detected. The methods include a signal expansion type algorithm that is used to process the pulse-compressed return signal. Specifically, a generalized Fourier expansion expression having a summation of PSF terms is used to expand the pulse-compressed signal. Each term represents a respective target and includes a point spread function and a complex coefficient. The signal expansion procedure can be used to determine a set of optimum complex coefficients, with one coefficient for each range bin. Doppler frequency can be used together with range to optimize the complex coefficients. Next, targets are detected by analyzing each range bin to determine whether the corresponding complex coefficient has an absolute magnitude greater than a pre-determined threshold.
    Type: Grant
    Filed: March 29, 2005
    Date of Patent: July 24, 2007
    Assignee: Information Systems Laboratories, Inc.
    Inventor: Katsumi Ohnishi
  • Patent number: 7236121
    Abstract: An interceptor-based sensor clusters tracks of objects to generate track clusters based on an uncertainty associated with each track, and generates feature vectors for a cluster under test using the relative placement and the population of other track clusters. The feature vectors may include one or more of a cluster count feature vector (N), a cluster population density feature vector (P), a cluster proximity feature vector (r), a cluster-weighted centroid feature vector (L) and a cluster scattering feature vector (?). The interceptor-based sensor generates belief functions (?) from corresponding feature vectors of clusters of tracks generated from a ground-based sensor and the interceptor-based sensor. The interceptor-based sensor may also associate the tracks with a cluster having a track of interest identified by a ground-based sensor based on the belief functions and may select one of the tracks for intercept of a corresponding object within the threat object cloud.
    Type: Grant
    Filed: June 13, 2005
    Date of Patent: June 26, 2007
    Assignee: Raytheon Company
    Inventor: Timothy E. Caber
  • Patent number: 7221307
    Abstract: An active or passive sensor observes a region, and generates evidence of the type of target or object viewed. The evidence is processed to determine the prior probability that the object is of a particular type. The prior probability so determined is thresholded to produce an indication of the presence of multiple targets or objects in a range bin, suggestive of shadowing of a target.
    Type: Grant
    Filed: July 8, 2004
    Date of Patent: May 22, 2007
    Assignee: Lockheed Martin Corporation
    Inventor: Mark A. Friesel
  • Patent number: 7218270
    Abstract: A-Track is a tracking process that is driven by automatic target recognition techniques (ATR), mobility analysis using digital maps and exploitation of other constraining information. It is structured as an optimization problem amenable to the formalism from classical relaxation labeling algorithm. The novel combination of techniques in A-Track provides a new approach to the temporal problem of establishing and extending target tracks through a sliding time window involving a sequence of multiple data frames. A data frame is a collection of sensor reports taken from one scan of a predetermined surveillance area that is being systematically and repeatedly scanned over time. The relative time differences between reports within a frame are generally much smaller than the time difference between different frames. A-Track is especially designed to handle cases having relatively large time intervals between frames that cause problems for conventional tracking algorithms based on predictive models.
    Type: Grant
    Filed: September 17, 2004
    Date of Patent: May 15, 2007
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventor: Louis A. Tamburino
  • Patent number: 7218274
    Abstract: System and method for detection and tracking of targets, which in a preferred embodiment is based on the use of fractional Fourier transformation of time-domain signals to compute projections of the auto and cross ambiguity functions along arbitrary line segments. The efficient computational algorithms of the preferred embodiment are used to detect the position and estimate the velocity of signals, such as those encountered by active or passive sensor systems. Various applications of the proposed algorithm in the analysis of time-frequency domain signals are also disclosed.
    Type: Grant
    Filed: October 21, 2003
    Date of Patent: May 15, 2007
    Inventors: Orhan Arikan, Ahmet Kemal Ozdemir
  • Patent number: 7205927
    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.
    Type: Grant
    Filed: June 3, 2005
    Date of Patent: April 17, 2007
    Assignee: Raytheon Company
    Inventors: Kapriel V. Krikorian, Dwight J. Mellema, Michael Y. Pines
  • Patent number: 7199750
    Abstract: A real-time signal processing engine robustly detects, localizes, tracks and classifies ground targets based on radar signals from a multistatic radar system. The system differentiates between different targets based on an optimized cost function, which can include the total returned normalized pulse energy. The local transmitters/receivers can communicate with each other via the transmitted radar signals.
    Type: Grant
    Filed: April 22, 2005
    Date of Patent: April 3, 2007
    Assignee: BBN Technologies Corp.
    Inventors: John Michael Bourdelais, Ernest Scott Stickels, William Ray Wright, David Earl Norris, Michael Anthony Tiberio, Gary Dana Butler
  • Patent number: 7193557
    Abstract: Tracking objects by receiving a dataframe from a detection sensor device, the dataframe containing a timestamp and data corresponding to each detected object, generating new observation nodes for each detected object, propagating group track state parameters to obtain posterior observable positions and projecting them onto the received dataframe, generating gates for the posterior observable positions and projecting them onto the received dataframe, determining feasible track node and feasible observation node assignments based on the proximity of the new observation nodes to the gates, updating track node state parameters and corresponding scores, performing a multi-frame resolution algorithm to resolve group track nodes into subtrack nodes, determining a set of feasible composite assignments for composite sets of track nodes and observation nodes, updating track node state parameters and corresponding scores, and determining a selected set of joint assignments based on the feasible composite assignments and
    Type: Grant
    Filed: April 29, 2004
    Date of Patent: March 20, 2007
    Assignee: Lockheed Martin Corporation
    Inventors: Michael A Kovacich, Thomas R Casaletto
  • Patent number: 7193555
    Abstract: A method for receiving at least one signal emitted by at least one emitter includes defining a first dwell associated with a first signal. The first dwell has a frequency range that overlaps at least a portion of a frequency range of a second signal. The method also includes detecting the second signal responsive to the first dwell if the first dwell satisfies at least one criterion for detecting the second signal. The method further includes rejecting the second signal responsive to a characteristic of the second signal if the first dwell fails to satisfy the at least one criterion.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: March 20, 2007
    Assignee: Lockheed Martin Corporation
    Inventor: Anthony J. Gounalis
  • Patent number: 7183964
    Abstract: A frequency-stepped radar may be used to detect buried landmines by sequentially inducing vibrations of different frequencies in the landmine. A sensor detects signals associated with the vibrations, and a processor processes the signals to detect the landmine.
    Type: Grant
    Filed: August 7, 2006
    Date of Patent: February 27, 2007
    Assignee: L-3 Communications CyTerra Corporation
    Inventors: William Steinway, Waymond Scott
  • Patent number: 7180442
    Abstract: A method of identifying an unknown target comprising creating a density function of cepstral coefficients for a known target; receiving a signal from the unknown target; transforming the signal from a time spectrum to a frequency spectrum using a Fourier transform; transforming the frequency spectrum to a cepstrum; creating a density function of cepstral coefficients for the unknown target; and comparing the density function of the unknown target with the density function of the known target.
    Type: Grant
    Filed: May 3, 2006
    Date of Patent: February 20, 2007
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Thach N. Nguyen
  • Patent number: 7176826
    Abstract: A system and method is provided for detecting emitter signals and for determining a scan strategy for a receiver system that receives such emitter signals. A rule-based system is provided for determining how emitters should be detected by a detection system. Rules may be used to prioritize certain emitters with respect to other emitters. The rules may also specify parameters for emitter modes, such as probability of intercept, turn-on range, detect-by range, tolerance, tolerance direction, scan periods, and other parameters. The rules may be used to compute the revisit time for the receiver. Multiple sets of rules may be created and a scan strategy may be computed based upon the selected rule set.
    Type: Grant
    Filed: December 28, 2005
    Date of Patent: February 13, 2007
    Assignee: Lockheed Martin Corporation
    Inventor: Anthony J. Gounalis
  • Patent number: 7167127
    Abstract: The invention is process for tracking a moving targeted vehicle from a remote sensor platform comprising the steps of 1) tracking the targeted vehicle and periodically recording its radar signature until its identity becomes ambiguous, 2) tracking the target after it has left its ambiguous state and periodically recording its radar signature; and 3) comparing the recorded radar signatures prior to the targeted vehicle becoming ambiguous to the recorded radar signature taken after the targeted vehicle has left its ambiguous state and determining that the targeted vehicle now tracked is the same as the targeted vehicle being tracked prior to becoming ambiguous.
    Type: Grant
    Filed: November 8, 2004
    Date of Patent: January 23, 2007
    Assignee: Northrop Grumman Corporation
    Inventors: Noel Collins, Rick Bottone, Donald R. McMillan
  • Patent number: 7142150
    Abstract: A method and system for detecting an object uses a composite evidence grid based on dual frequency sensing. A source transmits a laser transmission in a first zone. A detector receives a reflection of the laser transmission from an object in the first zone to determine laser observed data associated with points on the object. A transmitter transmits a radar transmission in a second zone that overlaps with the first zone. A receiver receives a reflection of the radar transmission from an object in the second zone to determine radar observed data associated with points on the object. The laser observed data is processed to form a laser occupancy grid for the first zone and the radar observed data is processed to form a radar occupancy grid for the second zone. An evaluator evaluates the radar occupancy grid and the laser occupancy grid to produce a composite evidence grid for at least an overlapping region defined by the first zone and the second zone.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: November 28, 2006
    Assignee: Deere & Company
    Inventor: Robert George Thackray
  • Patent number: 7132977
    Abstract: A design methodology for jointly optimizing the transmit waveform and receiver filter for multiple target identification is presented in presence of transmit signal dependent clutter like interference and noise. The methodology is applied and illustrated for various multiple ‘target ID’ problems in presence of transmit signal dependent clutter like interference and noise. The resulting correct target classification is significantly better than that achieved by a conventional chirp or any other transmit waveform. Unlike the classical radar case, the choice of transmit pulse shape can be critically important for the detection of extended targets in presence of additive channel noise and signal-dependent clutter.
    Type: Grant
    Filed: March 1, 2006
    Date of Patent: November 7, 2006
    Inventor: S. Unnikrishna Pillai