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: A radar detection technique in a WLAN device can include a short pulse detection technique and a long pulse detection technique that can be performed using multiple receive chains. Short pulse detection is particularly effective when the incoming signal includes one or a limited number of main pulses and some residual pulses. In contrast, long pulse detection is particularly effective when the incoming signal is longer, thereby allowing various characteristics of the incoming signal to be accurately measured.

Abstract: A method of adapting weather radar thresholds is disclosed. The method comprises generating a location from a location sensor, retrieving information representative of a weather type from a database, based on the location, and adjusting, automatically, the threshold for a radar display based on the information.

Abstract: A transmit-receive FM-CW radar apparatus according to one mode of the invention comprises: a mixer for downconverting an IF signal; a switch provided on the input side of the mixer; and a switch controller for controlling the switch on and off in different modes and selecting the IF signal in the different modes for supply to said mixer. A transmit-receive FM-CW radar apparatus according to another mode of the invention comprises: a mixer for downconverting an IF signal; a switch for turning on and off a local signal to be supplied to the mixer; and a switch controller for controlling the switch on and off in different modes and selecting the local signal in the different modes for supply to the mixer.

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: A system in accordance with the present invention determines signal attenuation for an electronic support measure receiver. The system includes a detection module for receiving electromagnetic signals from a surrounding environment and a processing module for chronologically segregating the electromagnetic signals into a plurality of dwells. The processing module controls the processing of the plurality of dwells. The processing module determines an analysis dwell from the plurality of dwells. The processing module computes a coarse attenuation for the analysis dwell. The processing module further computes a fine attenuation from the coarse attenuation and an offset table value.

Abstract: A method for processing a received, modulated pulse (i.e. waveform) that requires predictive deconvolution to resolve a scatterer from noise and other scatterers includes receiving a return signal; obtaining L+(2M?1)(N?1) samples y of the return signal, where y(l)={tilde over (x)}T(l) s+v(l); applying RMMSE estimation to each successive N samples to obtain initial impulse response estimates [{circumflex over (x)}1{?(M?1)(N?1)}, . . . , {circumflex over (x)}1{?1}, {circumflex over (x)}1 {0}, . . . , {circumflex over (x)}1{L?1}, . . . , {circumflex over (x)}1{L}, {circumflex over (x)}1{?1 +(M?1)(N?1)}]; computing power estimates {circumflex over (?)}1(l)=|{circumflex over (x)}1(l)|? for l=?(M?1)(N?1), . . . , L?1+(M?1)(N?1) and 0<??2; computing MMSE filters according to w(l)=?(l) (C(l)+R)?1s, where ?(l)=E[|x(l)|?] is the power of x(l), for 0<??2, and R=E[v(l) vH(l)] is the noise covariance matrix; applying the MMSE filters to y to obtain [{circumflex over (x)}2{?(M?2)(N?1)}, . . .

Abstract: A radio frequency device has an antenna for capturing an incoming signal for processing by the device or for radiating an outgoing signal from the device and a signal processor having one or more synchronous oscillators responsive to an input signal for providing an amplified output signal without using much power. An application is a radio frequency (RF) transponder (tag) for receiving an RF signal from an interrogator includes a tag antenna for receiving the RF signal from the interrogator and a receiver section connected to the tag antenna wherein the receiver consumes a significantly lower amount of power than conventional receiver technologies by using one or more synchronous oscillators.

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.

Abstract: A unit is described that is configured to control detonation of a munition such that the munition is detonated at a desired altitude. The unit includes a radar transmitter, a radar receiver that includes a radar range gate, and a sequencer. The sequencer is configured to receive a detonation altitude and set the range gate based on the received detonation altitude. The unit is also configured to output a detonation signal when radar return pulses received by the receiver aligned with gate delay pulses from the range gate.

Abstract: A method and apparatus comprising four co-planar metallic plates, two for transmission and two for reception, in which each pair of co-planer metallic plates of overall length L are disposed either in direct contact with the earth or are elevated a distance Z above the earth to form a capacitor comprising the metallic plates and the earth if Z=0 or if Z>0, the metallic plates, the air space and the earth. A short voltage or current pulse is applied to this capacitor via a transformer in which the magnetic flux current is adjusted to provide a pulse of the desired frequency composition in the air-earth propagation medium. This results in a frequency controlled pulse of electromagnetic radiation into the targeted subterranean geology at frequencies <500 KHZ.

Abstract: A system and method are described that use impulse radio technology to enhance the capabilities of a robot. In one embodiment, a system, a robot and a method are provided that use the communication capabilities of impulse radio technology to help a control station better control the actions of the robot. In another embodiment, a system, a robot and a method are provided that use the communication, position and/or radar capabilities of impulse radio technology to help a control station better control the actions of a robot in order to, for example, monitor and control the environment within a building.

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. In one embodiment, the scan strategy may be computed to operate in a manner cognizant of on-board active jammers, optimizing the jammer band and intercept band performance. The additional inputs for this task are a jammer band assignment table, and a blanking assignment table. The capability to generate “dry” (no jam) and “wet” (jamming) scan strategies for an emitter set is provided, with separate intercept rules for each.

Abstract: A radar transmits electromagnetic energy in pulse repetition intervals and receives reflections from objects in range gates including Doppler filters. The radar approves desirable ambiguous echoes and suppresses ambiguous echoes of no interest or that interfere with the radar's display. The radar frequency varies according to a staggered or wobbling pattern. The ambiguous echoes produce one pulse in the range gates within a predetermined number of periods. The Doppler filter works with an impulse function response that includes a small number of samples. The Doppler filter, during the predetermined number of periods, gives rise to independent samples from reflectors within the radar's unambiguous range. When the independent samples exceed the small number of samples, the radar approves the ambiguous echo. Otherwise, it is suppressed. In this way, ambiguous echoes are prevented from interfering with the reception or display of echoes. The suppression of asynchronous interferences can be made easier.

Abstract: In a police radar detector, a sweep signal defines at least one first sweep signal and at least one second sweep signal with the at least one second sweep signal being seamlessly inserted into the first sweep signal so that the first sweep signal is interrupted during the second sweep signal and restored after completion of the second sweep signal so that the first sweep signal can be continued. The frequencies swept by the at least one second sweep signal are thus overswept. By assigning the frequencies swept during the at least one first sweep to the radar bands of interest and the frequencies swept during the at least one second sweep to the frequencies used in the POP mode of operation by police radar, the short bursts of energy used in the POP mode can be detected.

Abstract: A system and method for calibrating a vehicular traffic surveillance Doppler radar are disclosed. In one embodiment, a modulation circuit portion generates double-modulated FM signals. An antenna circuit portion transmits the double-modulated FM signals to a target and receives reflected double-modulated FM signals therefrom. A calibration circuit portion responds to the reflected double-modulated FM signals by sending a calibration signal to the modulation circuit. The calibration signal is indicative of a relationship between a first range measurement derived from phase angle measurements associated with the reflected double-modulated FM signals and a second range measurement derived from speed and time measurements associated with the reflected double-modulated FM signals.

Abstract: A target determination apparatus includes a reception unit, a judgment unit, and a determination unit. The reception unit receives a reflection wave from a target. The judgment unit judges as to whether or not a fluctuation state of reception intensity of the reflection wave with time corresponds to a distinction state occurring when the target is a predetermined type, on the basis of information concerning the reception intensity of the reflection wave. The determination unit determines type of the target on the basis of judgment result of the judgment unit.

Abstract: Systems and methods of tracking a beam-aspect target are provided. In embodiments, a target is tracked with a Kalman filter while detections are received. After a detection is missed, the Kalman filter may be concurrently propagated with a blind-zone particle filter until a probability that the target is in a blind zone exceeds a threshold. When the probability exceeds the threshold, the Kalman filter may refrain from further propagating. After a gated detection is received, the blind-zone particle filter and an unrestricted-zone particle filter may be concurrently propagated while a probability that the target is in an unrestricted zone exceeds a threshold. The system may return to tracking with the Kalman filter when a covariance of the unrestricted-zone particle filter falls below a predetermined covariance.

Abstract: Applicants' ATR system is weather-agile because it is comprised of a primary target sensing means that is capable of surveilling the target scene in foul or fair weather, and a secondary target sensing means that is also capable of sensing targets in various weather. The primary and secondary sensing means communicate through a control center so that ultimately, among several weapons available, the most strategically located and equipped weapon is activated for the destruction of a selected target, given the weather. The control center accomplishes the communication by receiving the sensed target signature from the primary sensing means, processing the signature using database already resident in the center and transmitting the processed target signature to the weapon possessing the greatest potential for successfully destroying the target.

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.

Abstract: A plurality of sensor vehicles collect imaging data from an assigned location of a target region having targets and non-targets. The imaging data may be combined based on its location and the combined data is matched to a threat object map to identify the actual targets from the non-targets. In some embodiments, the sensor vehicles may be redirected to collect velocity and/or range information on the identified targets.

Abstract: A time domain communications system wherein a broadband of time-spaced signals, essentially monocycle-like signals, are derived from applying stepped-in-amplitude signals to a broadband antenna, in this case, a reverse bicone antenna. When received, the thus transmitted signals are multiplied by a D.C. replica of each transmitted signal, and thereafter, they are, successively, short time and long time integrated to achieve detection.

Abstract: Analysis of electromagnetic (or acoustic) multipath propagation inventively confines the assessment of multipath propagation to a “surface interactive region” (“SIR”), intermediate the target and transmitter and/or the target and receiver. The down range time of the propagation, translatable to range distance, is related to error associated with such restriction. A SIR scope is selected commensurately with acceptable error. Jointly disclosed (practicable therewith or thereapart) is inventive focus upon the transmitter-to-target propagation (transmitted propagation reaching target via both direct pathway and forward scattered pathway) and the target-to-receiver propagation (re-transmitted propagation reaching receiver via both direct pathway and forward scattered pathway). Transmitter-to-target propagation is calculated using conventional multipath modeling technique.

Abstract: The invention is a system and method for verifying the radar signature of a pair of aircraft. The system includes a radar transmitter and receivers located in the leading and trailing edge of the wing at the wing tip of the aircraft such that when flying the aircraft in formation with one aircraft behind the other aircraft, each aircraft can illuminate the other and verify the radar signature of the other.

Abstract: An arrangement for reducing the effect of vibration-induced changes in phase of the first local oscillator in a tracking receiver wherein final detection is accomplished by a synchronous detector in a phase lock loop incorporating a voltage-controlled oscillator is shown to include a differentiator providing a control signal whenever a vibration-induced change occurs, such control signal being applied to cause the time taken for the voltage-controlled oscillator to regain proper phase is reduced to a minimum.

Abstract: An apparatus for and method of employing synthetic aperture radar (SAR) images to automatically classify a target comprising emitting and collecting SAR signals at a plurality of squint angles, forming a plurality of SAR images of the target from the collected signals, the plurality of SAR images substantially having tilt angle diversity, automatically classifying the target from each of the plurality of SAR images, and generating a most probable target classification from the classifications of the plurality of SAR images.

Abstract: Target detection in the presence of non stationary clutter is improved by a radar receiver on a moving platform for detecting a target using a plurality of short coherent arrays and a plurality of long coherent arrays synthesized from the short coherent arrays overlapping the target. The target is obscured by slow scale clutter and fast scale clutter in the vicinity of the target.

Abstract: A millimeter wave pulsed radar system includes a radar synthesizer having a voltage controlled oscillator/phase locked loop (VCO/PLL) circuit, direct digital synthesizer (DDS) circuit and quadrature modulator circuit that are operative to generate an intermediate frequency local oscillator signal (IF/LO signal). A radar transceiver is operative with the radar synthesizer for receiving the IF/LO signal. A transmitter section has a frequency multiplier that multiplies the IF/LO signal up to a millimeter wave (MMW) radar signal and a receiver section and includes a direct conversion mixer that receives a MMW radar signal and the IF/LO signal to produce I/Q baseband signals that are later digitized and processed.

Abstract: A method, an arrangement and a radar level gauging system for preventing interference, which radar level gauging system comprises at least two radar level gauges arranged to measure a filling level of a product kept in a container. Microwave pulses are transmitted towards the surface of said product and microwave pulses reflected by said surface are received by said at least two radar level gauges. Information is provided with said microwave pulses and said information is used for controlling the measurement pulses of said at least two radar level gauges.

Abstract: The present invention is directed to a system and method for Doppler track correlation for debris tracking in PCL radar applications. The disclosed embodiments describe the systems and methods used in the detection of debris pieces and the association of the Doppler signals from the debris pieces across multiple illumination channels. The present invention also provides computation of debris state vectors and the projection of trajectories to determine debris impact points.

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. However, it is possible that the scan strategy is not realizable because of capacity constraints within the receiver system itself. One embodiment of the invention provides a method for detecting and correcting such a situation.

Abstract: A short-range radar system includes short-range radar sensor means and means (41) for HF-impulse generator for the sensor means. The means for HF-impulse generation are embodied for emitting impulses with adjustable pulse duration (51, 53).

Abstract: A radar detection process includes computing a derivative of an FFT output signal to detect an object within a specified detection zone. In one embodiment, a zero crossing in the second derivative of the FFT output signal indicates the presence of an object. The range of the object is determined as a function of the frequency at which the zero crossing occurs. Also described is a detection table containing indicators of the presence or absence of an object within a respective radar beam and processing cycle. At least two such indicators are combined in order to detect the presence of an object within the detection zone and with changing range gates in each of the antenna beams the coverage of the detection zone can be varied.

Abstract: A mechanism for combining signals of multiple radars to achieve increased range, radar sensitivity and angle accuracy is provided. A first signal beam is radiated from an antenna of a first radar in the direction of a target. A second signal beam is radiated from an antenna of a second radar in the direction of the same target. The echo signals from the first signal beam and the second signal beam are received at both radars. The echo signals received at the first radar are processed to produce first radar processed echo signals and the echoes signals received at the second radar are processed to produce second radar processed echo signals. The first and second radar processed echo signals are combined to form an aggregate value.

Abstract: A see-through-the-wall (STTW) imaging system uses a plurality of geographically separated positioning transmitters to transmit non-interfering positioning signals. An imaging unit generates a synthetic aperture image of a target by compensating for complex movement of the imaging unit using the positioning signals. The imaging unit includes forward and aft positioning antennas to receive at least three of the positioning signals, an imaging antenna to receive radar return signals from the target, and a signal processor to compensate the return signals for position and orientation of the imaging antenna using the positioning signals. The signal processor may construct the synthetic aperture image of a target from the compensated return signals as the imaging unit is moved with respect to the target. The signal processor may determine the position and the orientation of the imaging unit by measuring a relative phase of the positioning signals.

Abstract: The system and method for standoff detection of human carried explosives (HCE) is a portable system that automatically detects HCE up to a range of 200 meters and within seconds alerts an operator to HCE threats. The system has radar only, or both radar and video sensors, a multi-sensor processor, an operator console, handheld displays, and a wideband wireless communications link. The processor receives radar and video feeds and automatically tracks and detects all humans in the field of view. Track data continuously cues the narrow beam radar to a subject of interest, the radar repeatedly interrogating cued objects, 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. Once a determination is made, the system alerts operators through a handheld display and mitigates the threat if desired.

Abstract: A security inspection system uses microwave radiation to image targets on a human subject or other item. The system includes an array of antenna elements that are programmable with a respective phase delay to direct a beam of microwave illumination toward a target on the human subject or item. The antenna elements are further capable of receiving reflected microwave illumination reflected from the target. 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 human subject or item. Multiple beams can be directed towards the human subject or item to obtain corresponding pixel values for use by the processor in constructing the image.

Abstract: A method of controlling a switching element in a switching regulator power supply of a radar. The method of controlling the switching element comprises only switching the switching element during predetermined time intervals, the predetermined time intervals advantageously being sample intervals of a pulse repetition interval of the radar. Thereby by having knowledge of the time intervals the switching element is switching, being able to remove or diminish any influence the switching can have on the quality of received signals and subsequent processing of these signals.

Abstract: A radar and laser detection device for mounting upon a motorcycle is described which provides increased concealment, security, safety, ease of use and functionality specific to the needs of motorcycle drivers. A method of semi-permanently mounting the device is described which requires no permanent alterations to the vehicle while providing improved visibility of alarm signals, a simple display technique, and controls which do not require the operator to remove his/her hands from the vehicle handlebars.

Abstract: A method of tracking a moving object in an image created by use of a synthetic aperture includes identifying a plurality of receive phase centers for an image collector, obtaining a synthetic aperture image using the plurality of receive phase centers, and reading a signature of the moving object based on the synthetic aperture image, where the reading of the signature includes identifying, in the synthetic aperture image, as a function of image collection time, a presence of the moving object. The reading of the signature may also include identifying a changing position of the moving object, and may include associating a plurality of range difference values with respective ones of the plurality of phase centers. A signature of a scatterer may be formed using only its associated ?R-versus-time profile. The presence of a mover in the image may be determined by filtering the image to detect all or part of a signature, or by using one or more signatures to train a neural network to observe the mover directly.

Abstract: A method for processing a received, modulated pulse (i.e. waveform) that requires predictive deconvolution to resolve a scatterer from noise and other scatterers includes receiving a return signal; obtaining L+(2M?1)(N?1) samples y of the return signal, where y(l)={tilde over (x)}T(l)s+v(l); applying RMMSE estimation to each successive N samples to obtain initial impulse response estimates [{circumflex over (x)}1{?(M?1)(N?1)}, . . . , {circumflex over (x)}1{?1}, {circumflex over (x)}1{0}, . . . , {circumflex over (x)}1{L?1}, {circumflex over (x)}1{L}, . . . , {circumflex over (x)}1{L?1+(M?1)(N?1)}]; computing power estimates {circumflex over (?)}1(l)=|{circumflex over (x)}1(l)|2 for l=?(M?1)(N?1), . . . , L?1+(M?1)(N?1); computing MMSE filters according to w(l)=?(l)(C(l)+R)?1s, where ?(l)=|x(l)|2 is the power of x(l), and R=E[v(l)vH(l)] is the noise covariance matrix; applying the MMSE filters to y to obtain [{circumflex over (x)}2{?(M?2)(N?1)}, . . . , {circumflex over (x)}2{?1}, {circumflex over (x)}2{0}, .

Abstract: A time domain communications system wherein a broadband of time-spaced signals, essentially monocycle-like signals, are derived from applying stepped-in-amplitude signals to a broadband antenna, in this case, a reverse bicone antenna. When received, the thus transmitted signals are multiplied by a D.C. replica of each transmitted signal, and thereafter, they are, successively, short time and long time integrated to achieve detection.

Abstract: A method and system for adaptively reducing, in a displacement signal having a value indicative of a measured angular displacement between an antenna boresight and an apparent line of sight to a target, a noise signal having a value indicative of an angular error induced by a shift in the target radar centroid so as to provide an output signal having a value indicative of an estimate of a true angular displacement signal between the antenna boresight and a true line of sight to the target.

Abstract: The invention concerns a passive radar receiver for a received orthogonal frequency division multiplex-type signal consisting of symbol frames each emitted on coded orthogonal carriers. After formatting the received signals into digital symbols (S1 S1), a filtering circuit (2) eliminates by subtraction or using a covariance matrix, in the symbol signal at least unwanted signals with null Doppler effect so as to apply a filtered signal (X?) including essentially signals backscattered by mobile targets to a Doppler-distance correlator (4).

Abstract: A synthetic aperture radar (SAR) compensates for ionospheric distortions based upon measurement of the group delay, particularly when operating in the VHF/UHF band. The SAR is based upon a multi-input multi-output (MIMO) technique for estimating the effective ionospheric conditions, which is referred to as the group delay approach. The group delay approach is divided into a 1-dimensional (range) approach and a 2-dimensional (range and cross-range) approach. The group delay measures the effective or observed TEC, which is used to reduce the ionospheric distortion.

Abstract: A synthetic aperture radar (SAR) for a moveable platform includes an antenna, a radar transmitter and radar receiver cooperating with the antenna. A radar processor is connected to the radar transmitter and radar receiver to account for the Faraday rotation introduced by propagation through the ionosphere by estimating an individual ionospheric distortion for each received echo pulse based upon a measured Faraday rotation, and reducing the ionospheric distortion for each received echo pulse based upon the estimated individual ionospheric distortion associated therewith for providing a compensated echo pulse.

Abstract: The present invention includes an application of a dynamic logic algorithm to detect slow moving targets. Show moving targets are going to be moving in the range from 0-5 mph. This could encompass troop movements and vehicles or convoys under rough terrain.

Abstract: A video amplifier for a radar receiver includes a temperature compensating attenuator. The attenuator includes a temperature sensitive device, such as a thermistor, arranged in a voltage divider network and is coupled in cascade between two filter stages. Each of the filter stages has a bandpass characteristic in order to filter low-frequency leakage signals and provide sensitivity control based on frequency and thus range, while also filtering high frequency signals to reduce aliasing.

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. Data is provided that specifies one or more emitters or emitter types desired for detection. An algorithm evaluates the cost, in terms of receiver resources, of using one or more different detecting methods to create a receiver scan strategy for the desired emitters or emitter types.

Abstract: A radar detector for alerting an operator of a motor vehicle to an incoming police radar signal. This radar detector includes a microprocessor; a circuit coupled to the microprocessor for detecting the incoming police radar signal; and a global positioning system receiver coupled to the microprocessor. Upon detection of an incoming radar signal, the radar detector can utilize the position, velocity, and/or heading data from the global positioning system receiver to determine whether to generate an alert.