Abstract: A method for processing radar return data to determine a physical angle, in aircraft body coordinates to a target, is disclosed. The radar return data includes a phase difference between radar return data received at an ambiguous radar channel and a left radar channel, a phase difference between radar return data received at a right radar channel and an ambiguous radar channel, and a phase difference between radar return data received at a right radar channel and a left radar channel. The method includes adjusting a phase bias for the three phase differences, resolving phase ambiguities between the three phase differences to provide a signal, and filtering the signal to provide a physical angle to the target in aircraft body coordinates.

Abstract: A system employs null angle measurements developed in response to the detection of radiation, such as jamming, along with the positions at which the null angles are measured, to determine the location of the radiation source through reverse triangulation.

Abstract: An algorithm for improved tracking of Air Traffic Control Radar Beacon System transponders is disclosed. The algorithm can be combined with a system that includes an interrogator which transmits an interrogation signal to an associated vehicle transponder at a first frequency, preferably 1030 MHZ in accordance with FAA regulations, and a receiver array which receives the transponder reply signal transmitted by the transponder at a second frequency, preferably 1090 MHZ in accordance with FAA regulations. An angle of arrival processor calculates an angle of the received reply signal, and a position processor calculates the vehicle position based on at least the received angle data.

Abstract: Emitter target range and heading are estimated from bearing measurements enhancing bearings-only estimator convergence to a target track, and permitting optimization of an observer position relative to the target at the end of the total bearing measurement period. One or more estimates of the target range, speed and heading made from bearing measurements before an observer maneuver are used to determine the most appropriate observer maneuver giving complete bearings-only target-motion-analysis observability. A set of parameters characterizing a set of potential emitter signal sources is generated based on measured emitter characteristics. A most probable set of emitter platforms is identified and the emitter operating mode and corresponding platform set are associated with a kinematic regime set. A specific speed or discrete set of speeds best adapted to a set of all possible platform missions, emitter speed as a continuous function of emitter range, and emitter range are all determined.

Abstract: A system for identification and tracking of microwave responsive tags, the system comprising, a microwave responsive tag having a passive modulating element to uniquely backscatter directed microwave beams, a microwave base station for directing microwave beams in room sized areas, and a tag tracking system receiving input from the microwave base station, the tag tracking system storing state records of position and informational content of the microwave tag.

Abstract: A radar device (2) includes plural transmission antennas and plural reception antennas. The reception antennas constitute a reception-side antenna portion (20) and are arranged at an interval of d. The transmission antennas constitute a transmission-side antenna portion (18) and are arranged at an interval of d′=d×(n−1). The path length at which the electric wave is reflected from a target is identical between channels A9 and B1, and seventeen kinds of channels (A1 to A8, A9 or B1, B2 to B9) which are different in path length by every fixed distance are achieved. The data of the channels (A1 to A9 and B1 to B9) using different transmission antennas are respectively collected in different measuring cycles, and an error based on the time difference between the measuring cycles is corrected on the basis of a correction value calculated from the data of the channels A9, B1.

Abstract: A plurality of roadside wireless devices are provided on a roadside of an entry of a toll area. A first roadside wireless device, which communicates with a vehicle-mounted device over wireless communication, sends unique information obtained from the vehicle-mounted device to a second roadside wireless device located, downstream to the first roadside wireless device, along a moving direction of the vehicle. The second roadside wireless device checks if unique information on the vehicle-mounted device obtained from the vehicle-mounted device matches the unique information on vehicle-mounted device notified from the first roadside wireless device to judge if the moving direction is a direction of entry into a toll area and charges the vehicle-mounted device for toll only when it is judged that the moving direction is the direction of entry into the toll area.

Abstract: Methods and apparatus are disclosed for measuring position and motion of a “marker” antenna (14), disposed on a subject (12) at a physical location to be tracked. Relative distance of the marker antenna (14) from receiving antennas (18) is measured by phase differences of its microwave signals (40) at the receiving antennas (18) for at least two successive marker positions. Alternatively, actual distances (104, 106) are calculated by choosing a source position (102) and iterating the distances (104, 106) until the calculated phase differences match those measured. Four to six receiving antennas (18) are positioned at edges of a volume (16) where activity is conducted. Each received signal (40) is amplified and down-converted in a mixer (44). A single reference oscillator (46) feeds all the mixers (42) to preserve phase relationships of the received signals. Received signals (40) are digitized and presented to a multi-channel digital tuner (50).

Abstract: A bistatic radar system (100), method and computer program (178) are provided for mapping of oceanic surface conditions. Generally, the system (100) includes at least one transmitter (102) and at least one receiver (106) located separate from one another, and each having a local oscillator locked to a Global Positioning System (GPS) signal received by a GPS synchronization circuit (134) to provide the necessary coherency between the transmitted and received signals. Preferably, the present invention enables an existing backscatter radar systems to be quickly and inexpensively upgraded to a bistatic radar system (100) through the addition of a transmitter (102) and/or receiver (106) separate from the backscatter radar system, the GPS circuit (134), and use of the computer program (178) and method of the present invention.

Abstract: In a method for detecting target objects and determining their direction, range, speed and the like for a radar device, the invention provides that at least three transmitting and receiving devices for radar beams are arranged in such a manner that their beam fields (a, b, c, d, e) form the dectection area of the radar device, and the at least three transmitting and receiving devices are activated and deactivated successively in such a manner that at least two adjacent transmitting and recieving devices are activated simultaneously.

Abstract: Apparatus for and methods of obtaining positional information about one or more objects in a detection field are disclosed. An array including a transmitting element and a plurality of receiving elements is provided. In one aspect a truncated cross-correlation function is applied to determine the interval between signals received by a plurality of the receiving elements, thereby to determine an angular position of an object. In another aspect a warning zone is defined and it is determined whether an object is within the warning zone. Also disclosed are techniques for stretching received signals, and techniques for obtaining positional information relating to an object using non-Doppler radar. Various implementations, modifications and applications of the techniques described are disclosed. Typical applications of the techniques described are with vehicles.

Abstract: A method for tracking a target vehicle through a curve in a roadway is disclosed. The method includes measuring an azimuth angle between the target vehicle and a host vehicle, calculating a relative velocity between the target vehicle and the host vehicle, developing a theoretical relationship, wherein the relationship is a function of the measured azimuth angle and the measured relative velocity, and comparing the developed theoretical relationship with measured relationship between the azimuth angle and the relative velocity. Further, the target vehicle is determined to be in the same lane or path of the host vehicle by evaluating how well the developed theoretical relationship fits the with the measured azimuth angle and calculated relative velocity. Therefore, the present invention determines the path of a target vehicle without relying on inaccurate conventional methods based on the yaw rate of the host vehicle.

Abstract: A method for testing a radar system utilizing flight test radar data is described. The method includes time synchronizing measured radar data with a GPS based time marker, storing at least a portion of the time synchronized radar data, storing the GPS data, processing the stored GPS data to correspond with a physical position of an antenna which received the radar data, providing a radar model, and comparing the processed radar model data to the stored radar data.

Abstract: A method of determining a target location from a vehicle is described. The method includes identifying the target utilizing a video system, determining an angular location vector to the target with respect to the vehicle, determining a position of the vehicle utilizing a digital terrain elevation map and precision radar altimeter, calculating a location where the angular location vector would intersect with the digital terrain elevation map, and generating a target position based on vehicle position and the location of the intersection of the angular location vector and digital terrain elevation map.

Abstract: A pulse radar system capable of mapping multiple targets essentially simultaneously using a single radar antenna. By alternately transmitting radar pulses toward multiple targets positioned at different angles relative to the antenna and alternately receiving return signals from the multiple targets as the radar antenna is switched between multiple beam positions, a time-interleaved radar operation is achieved which enables multiples targets to be mapped, and thus tracked, at the same time. A different radio frequency is preferably employed for each target so as to avoid interference and ambiguous returns. Using the teachings of the present invention, between two and twenty radar maps, and possibly more, can be generated simultaneously in approximately the same amount of time required to map a single target using conventional systems of the prior art.

Abstract: A system and method for detecting and tracking a target object, including the calculation of the target object's altitude, is disclosed. During the processing of signals received by a receiver, the system selectively calculates the altitude of the target object from signals modified by an interference effect pattern formed by the signals broadcast by a transmitter, or from the calculation of geometric shapes associated with three or more transmitters and determining the intersection point of those shapes.

Abstract: A method for determining a location of an emitter in a monitored area includes the step of providing an array representative of the monitored area, the array including a plurality of elements. Next, at least one first curve and at least one second curve is provided in the array. The first and second curves are representative of possible locations of the emitter in the monitored area. Then, possible emitter locations are identified at intersections of the first and second curves. The intersections are identified by determining locations in the array where an element having an assigned attribute corresponding to a first curve has a predetermined number of adjacent elements having an assigned attribute corresponding to a second curve.

Abstract: A method to determine a target azimuth with a radar. The radar sends out a wave of N-pulse bursts. The method includes in one burst: splitting up a N-pulse burst into two half bursts, of a front burst and a rear burst; filtering the front and rear bursts to associate an azimuth value &thgr;1 and an amplitude value A1 with the front burst, and an azimuth value &thgr;2 and an amplitude value A2 with the rear burst; and obtaining the target azimuth Az at a value corresponding to a maximum of a Gaussian curve passing through points having components (&thgr;1, A1) and (&thgr;2, A2).

Abstract: A phase processor is disclosed which is configured to receive processed radar return data from a left radar channel, a right radar channel, and an ambiguous radar channel. The phase processor comprises a plurality of phase detectors each with an input and a reference input. The phase detectors are configured to determine a phase difference between radar return data received at the input and radar return data received at the reference input.

Abstract: For interferometric and/or tomographic remote sensing by means of synthetic aperture radar (SAR) one to N receiver satellites and/or transmitter satellites and/or transceiver satellites with a horizontal across-track shift the same or differing in amplitude form a configuration of satellites orbiting at the same altitude and same velocity. Furthermore, a horizontal along-track separation, constant irrespective of the orbital position, is adjustable between the individual receiver satellites. In this arrangement one or more receiver satellites orbiting at the same altitude and with the same velocity are provided with a horizontal across-track shift varying over the orbit such that the maximum of the horizontal across-track shift occurs over a different orbital position for each satellite, the maxima of the horizontal across-track shifts are positioned so that the baselines are optimized for across-track interferometry.

Abstract: A system for reducing multi-path reflections from adjacent metal objects which cause distortion in an IFSAR includes a reflective cone extending between the top of the IFSAR and the skin of its aircraft, and a reflective shroud surrounding the IFSAR. Each of these components may be coated with radar absorbing material.

Abstract: A radar system and technique provide the capability to detect a target of interest and maintain the detection in the presence of multiple mainlobe and sidelobe jamming interference. The system and technique utilize digital beamforming to form sub-arrays for canceling jamming interference. Jamming is adaptively suppressed in the sub-arrays prior to using conventional deterministic methods to form the sum, &Sgr;, and difference, &Dgr;, beams for monopulse processing. The system and technique provide the ability to detect a target of interest, provide an undistorted monopulse ratio, m, and maintain target angle estimation, in the presence of multiple mainlobe and multiple sidelobe jammers.

Abstract: A system and method (32) for measuring line-of-sight angular rates for all-weather precision guidance of distributed projectiles (16) and a guidance system (10) based thereon. In accordance with the novel method (32) for measuring line-of-sight angular rates, first the range rates of the target (14) relative to at least two projectiles (16) is determined, as well as the position and velocity of each projectile (16). Then, the line-of-sight angular rate of the target (14) relative to at least one projectile (16) is computed from the range rates, positions, and velocities. In the illustrative embodiment, the range rate of the target (14) relative to a projectile (16) is determined based on a monostatic target Doppler measurement, a monostatic projectile Doppler measurement, a bistatic Doppler measurement of the target (14) by the projectile (16), and the carrier frequency of a data link (26) between the projectile and the shipboard system.

Abstract: A method for processing radar return data to determine a physical angle, in aircraft body coordinates to a target, is disclosed. The radar return data includes a phase difference between radar return data received at an ambiguous radar channel and a left radar channel, a phase difference between radar return data received at a right radar channel and an ambiguous radar channel, and a phase difference between radar return data received at a right radar channel and a left radar channel. The method includes adjusting a phase bias for the three phase differences, resolving phase ambiguities between the three phase differences to provide a signal, and filtering the signal to provide a physical angle to the target in aircraft body coordinates.

Abstract: An inexpensive, small, low-power consumption, wide-band, high resolution spectrum analyzer is provided as a listening device for throw-away applications such as surveillance that involve deployment of large numbers of battery-powered spectrum analyzer modules to detect a signal source such as two-way radio traffic. Power requirements are minimized by the utilization of only one chirp generator to elongate battery life while providing a high resolution result. In order to minimize power drain the spectrum analyzer includes a single compound-chirp Fourier Transform generator. The compound chirp generator is used in one embodiment with a surface acoustic wave, SAW, dispersive delay line in conjunction with a surface electromagnetic wave, SEW dispensive delay line.

Abstract: A series of police doppler single mode radars and a multimode police doppler radar, all with direction sensing capability are disclosed. A quadrature front end which mixes received RF with a local oscillator to generate two channels of doppler signals, one channel being shifted by an integer multiple of 90 degrees in phase relative to the other by shifting either the RF or the local oscillator signal being fed to one mixer but not the other. The two doppler signals are digitized and the samples are processed by a digital signal processor programmed to find one or more selected target speeds. Single modes disclosed are: stationary strongest target; stationary, fastest target; stationary, strongest and fastest targets; moving, strongest, opposite lane; moving, strongest, same lane; moving, fastest, opposite lane; moving, fastest and strongest, opposite lane; moving, fastest, same lane; moving fastest and strongest, same lane.

Abstract: The invention concerns a method and apparatus for cascaded processing of signals in a phased array antenna system in which a plurality of antenna elements are configured as a plurality of sub-arrays. A weighting factor is applied to each of the antenna elements to form a plurality of sub-array beams, each pointed in a selected direction. For each sub-array, an output from each the antenna elements in the sub-array can be combined to produce a sub-array output signal. The sub-array output signals are selectively weighted and combined in a fully adaptive process. Subsequently, the system can estimate an angle-of-arrival direction for a signal-of-interest (“SOI”) and at least one signal-not-of-interest (“SNOI”). Based on this estimating step, the system calculates a new set of weighting factors for controlling one or more of the sub-array beams to improve the signal-to-noise plus interference ratio obtained for the SOI in the array output signal.

Abstract: A system and method for imaging objects obscured by a covering layer of snow. The system preferably utilizes a continuous-wave radar generating short-wavelength radio-frequency (RF) signal beam-scanned over angular displacements following a scanning pattern toward a target area. Reflections of the:RF signal from objects buried beneath the snow are registered by an array of RF detectors whose signal magnitudes are summed arid correlated with scan direction to generate a signal providing spatial object information, Which by way of example, is visually displayed. The radio-frequency beam may be scanned over the scene electronically or by either mechanically or electromechanically modulating antenna direction or the orientation of a beam deflector. The system is capable of generating multiple image frames per second, high-resolution imaging, registration of objects to a depth exceeding two meters, and can be implemented at low cost without complex signal processing hardware.

Abstract: In a method and apparatus for controlling the distance of a vehicle to a vehicle traveling ahead, in which the distance and the relative velocity of the vehicle traveling ahead are measured and the distance, in a distance control mode, is controlled by accelerating or decelerating the vehicle to a preestablished setpoint distance, wherein the deceleration permitted by the distance control process is limited and, in situations in which the setpoint distance cannot be maintained at this limited deceleration, the transition is made from the distance control process to a process limiting the distance to a minimum distance which is smaller than the setpoint distance, and the vehicle, after reaching the minimum distance, is further decelerated, so that the distance once again increases to the setpoint distance.

Abstract: The relative movement of a receiver and transmitter in a communications system is used to advantage by electronically synthesizing a larger apparent antenna aperture, thereby increasing signal-to-noise ratio. The approach may be used regardless of whether the transmitter is fixed and the user or vehicle is moving, or the user or vehicle is fixed and the transmitter is moving. According to the method, the apparent angle between the receiver and transmitter is determined relative to the direction of movement and used to produce time-delayed replicas of the received signaling stream which are coherently added to synthesize the increased apparent receiver antenna aperture. Since only the receiver is modified according to the invention, existing transmitters and infrastructures can be used without modification. Significant cost potentials can be realized via economy of scale, due to relatively simple FFT processing.

Abstract: The presentation is a low-cost, two-way communication system and method for aid in locating an object, such as a container or a package and reporting the contents of the object to a site remote from the location of the object. In one embodiment, the system includes two modules. A remote module includes a directional antenna array mounted on the top of the module (i.e., in a remote site), a processor including a direction-finding software, and a display for pointing the direction of the container's location relative to the remote site.

Abstract: Methods and systems for determining the direction to a transponder are disclosed. The methods and systems include transmitting a first signal to an area where communications with a transponder is desired; producing a second signal desired from the first signal; receiving the second signal via a first and second antenna forming a difference signal from the second signal received via the first and second antennas; forming a third signal by adding the second signal received via the first antenna and the second signal received via the third antenna; delaying the difference signal; and comparing a fist polarity of the delayed difference signal with a second polarity of the third signal.

Abstract: An obstacle recognition system for automotive vehicles is provided which is designed to recognize targets such as preceding vehicles to be tracked by a radar by grouping data elements derived through a scan of a frontal detection range using laser pulses. The system determines the radius of a curve in a road on which a system vehicle is traveling and shifts one of the data elements from which the grouping operation is to be initiated as a function of the radius of the curve, thereby enabling the recognition of the targets without decreasing the control reliability even when the system vehicle is turning the curve.

Abstract: A radar apparatus of the present invention is provided with a reception array antenna having a plurality of antenna elements, a first bearing detector for detecting a bearing of a target by carrying out signal processing on individual element signals received on an element-by-element basis through the respective antenna elements, and a second bearing detector for detecting a bearing of a target by carrying out signal processing different from that of the first bearing detector, on the individual element signals received through the respective antenna elements. Since the radar apparatus is provided with the two detectors of the first bearing detector and second bearing detector as means for acquiring the target bearing, both or either one of the results of detection by the two detectors can be selectively utilized as occasion demands.

Abstract: Methods and systems for determining the direction to a transponder are disclosed. The methods and systems include transmitting a first signal to an area where communications with a transponder is desired; producing a second signal desired from the first signal; receiving the second signal via a first and second antenna forming a difference signal from the second signal received via the first and second antennas; forming a third signal by adding the second signal received via the first antenna and the second signal received via the third antenna; delaying the difference signal; and comparing a fist polarity of the delayed difference signal with a second polarity of the third signal.

Abstract: A method and system for are provided for detecting one or more radar targets of interest in the presence of jamming signals. A plurality of sub-arrays are formed from an antenna array. Sub-array beams are adaptively formed so as to point one or more nulls in one or more respective directions corresponding to one or more jammers. A super-resolution technique is applied to determine a count of the one or more radar targets and to determine the corresponding direction of arrival.

Abstract: Disclosed is a method to determine target azimuth by the use of a radar, especially of the ASR type. The radar sends out a wave of detections by N-pulse bursts. The method comprises at least the following steps in one burst: a step in which the burst is split up into two half bursts, one front burst and one rear burst; a step for the filtering of the half burst to associate an azimuth value &thgr;1 and an amplitude value A1 with the front burst, and an azimuth value &thgr;2 and an amplitude value A2 with the rear burst; a step to obtain the target azimuth Az at a value corresponding to the maximum of a Gaussian curve passing through the points having components (&thgr;1, A1), (&thgr;2, A2). The invention can be applied especially to surveillance radars used, for example, in air traffic management applications.

Abstract: A method for determining the velocity of features such as wind. The method preferably includes producing sensor signals and projecting the sensor signals sequentially along lines lying on the surface of a cone. The sensor signals may be in the form of lidar, radar or sonar for example. As the sensor signals are transmitted, the signals contact objects and are backscattered. The backscattered sensor signals are received to determine the location of objects as they pass through the transmission path. The speed and direction the object is moving may be calculated using the backscattered data. The data may be plotted in a two dimensional array with a scan angle on one axis and a scan time on the other axis. The prominent curves that appear in the plot may be analyzed to determine the speed and direction the object is traveling.

Abstract: A multi-channel radar apparatuses optimizes the number of channels used for detecting a body in terms of position detection precision and processing time reduction. The multi-channel apparatus detects the position of the body that produces reflecting waves by calculating, for example, the center of gravity using only the received signals of monostatic channels (B1, B3, and B5) when the level of the received signals is high and using the received signals of the monostatic channels (B1, B3, and B5), as well as the received signals of bistatic channels (B2 and B4) when the level of the received signals is low.

Abstract: A system identifies a number of targets within a main beam of an antenna array that transmits the main beam and receives echo returns from the main beam. A covariance matrix is generated using the echo returns. The presence of at least one target within a single range cell is detected. A plurality of consecutive pulses are transmitted in a direction of the single range cell within a sufficiently short period that the at least one target remains within the single range cell while the plurality of consecutive pulses are transmitted. An echo signal is sampled from each of the plurality of pulses. An updated covariance matrix is estimated each time the echo signal is sampled. An eigenvalue decomposition is updated each time the covariance matrix is updated. The number of targets in the single range cell is estimated, based on the updated eigenvalue decomposition.

Abstract: A protective device for a person, specifically for a person participating a sport, having at least one sensor device for detecting obstacles in the vicinity of the person to be protected; an evaluation device having a microcontroller for a situation evaluation with respect to the surroundings of the person to be protected; a triggering device for activating a protective application; and a protective application, which can be integrated in the equipment of the person to be protected.

Abstract: A system and method for mitigating co-channel interference is disclosed. A radar system detects targets from received signals at an antenna array. The received signals include direct signals and target signals transmitted from remote transmitters. An antenna array receives the signals. A signal processing system is coupled to the antenna array to perform processing operations on the received signals. The processing system includes a primary cancellation component and a secondary cancellation component. A primary illuminator signal is cancelled from the received signals by the primary cancellation component. An adaptive beam former obtains a secondary illuminator signal from the received signals. A reference regenerator regenerates the secondary illuminator signal. An adaptive cancellation filter removes noise from the secondary illuminator signal. The secondary cancellation component mitigates co-channel interference by canceling the secondary illuminator signal from the received signals.

Abstract: A method and apparatus for measuring the parameters of atmospheric turbulent flows utilizes the Doppler shifted frequencies of received radar signals backscattered from sound generated aerodynamically by atmospheric turbulent flows. Doppler frequency bandwidths of the received backscattered signals are used to estimate the atmospheric flow turbulence and the mean frequency within a bandwidth is processed to estimate its radial flow velocity. Total flow velocity and the flow velocity angle with respect to the antenna boresight of the atmospheric turbulent flow may be estimated by estimating the radial flow velocity at two radial positions and processing these radial velocities. Processing of the Doppler data is initiated when the total signal power within the Doppler frequency band exceeds a predetermined power level.

Abstract: When a question signal of a transmitting frequency band &Dgr;F1 output from a radar device is received in search and rescue radar trans-ponder (SART) of a wreck ship, a response signal is sent from the SART to the radar device. In the radar device, the response signal and an echo of the question signal are received as a reception signal, intensity of components of the reception signal placed in almost the same frequency band as the transmitting frequency band &Dgr;F1 of the question signal is suppressed to produce a filtered response signal, and components of the filtered response signal placed in a receiving frequency band &Dgr;F2, which does not overlap with the transmitting frequency band &Dgr;F1 of the question signal, are extracted from the filtered response signal as an image signal.

Abstract: Methods and systems for determining the direction to a transponder are disclosed. The methods and systems include transmitting a first signal to an area where communications with a transponder is desired; producing a second signal desired from the first signal; receiving the second signal via a first and second antenna forming a difference signal from the second signal received via the first and second antennas; forming a third signal by adding the second signal received via the first antenna and the second signal received via the third antenna; delaying the difference signal; and comparing a fist polarity of the delayed difference signal with a second polarity of the third signal.

Abstract: A method is described for detecting moving and/or stationary objects in the path of a vehicle, where the distance and velocity of the reflecting object are determined by using a radar sensor, where the frequency of the signal transmitted is modulated in the shape of a ramp according to a multi-ramp method, and some ramps have a lower slope in the frequency curve. The higher spectral components of the mixed signals from the ramps having the lower slope, which are to be assigned to a distance range of the reflecting object which is greater than the distance range belonging to the ramps having the greater slope, are used to determine the distance, speed and angle of objects.

Abstract: A radio direction finding system for a low signal quality transmission signal performs a Fast Fourier Transform (FFT) on an entire received RF band into a number of FFT bins, each serving as an IF filter. The contents of each FFT bin are demodulated to decode a frequency signature from the encoded RF signal. A signal-to-noise ratio comparator receives the FFT baseband samples and determines the signal level from the known frequency signature. The FFT baseband buffer with the greatest SNR corresponding to a particular FFT frequency bin is outputted as a direction finding metric.

Abstract: The bistatic radar system uses a scanning beam antenna located at the transmitter to transmit a focused beam of high frequency energy into a predefined space, with the transmitted beam comprising a series of pulses. The transmitter also includes apparatus for determining pulse origination data comprising: pulse origination time and direction of propagation for each of the pulses in the transmitted beam emanating from the antenna, where the antenna is scanned in a predetermined scan pattern in at least an azimuthal direction. The bistatic radar system also includes at least one receiver, located at a site remote from the transmitter and includes apparatus for generating pulse component receipt data indicative of receipt of components of the pulses that are contained in the transmitted beam that are reflected from scatterers in the predefined space.

Abstract: The bistatic radar network uses an incoherent transmitter for determining the presence, locus, motion, and characteristics of scatterers in a predefined space. The incoherent transmitter generates pulses of high frequency energy that vary in frequency and/or phase. The bistatic radar network having an incoherent transmitter uses a scanning beam antenna located at the transmitter to transmit a focused beam of high frequency energy into a predefined space, with the transmitted beam comprising a series of pulses, each pulse in the series of pulses having a varying frequency, phase, pulse origination time and direction of propagation as it is emanated from said antenna. The transmitter also includes apparatus for determining pulse origination data comprising: frequency, phase, pulse origination time and direction of propagation, for each of the pulses in the transmitted beam emanating from the antenna, where the antenna is scanned in a predetermined scan pattern in at least an azimuthal direction.

Abstract: This FM-CW radar apparatus comprises a transmitter section, a receiver section, and a signal processing section. The transmitter section transmits a frequency-modulated continuous wave as a transmitted wave. The receiver section receives a radio wave resulting from reflection of the transmitted wave at a target, as a received wave, by a receiving antenna comprising an array of antenna elements, generates a beat signal which is a difference of the transmitted wave and the received wave in each of channels of the respective antenna elements, and converts this beat signal to a digital beat signal by A/D conversion. The signal processing section executes a digital beamforming operation with the digital beat signals and detects the target from the result of the operation.