Abstract: There is provided a method for tracking a group having at least two targets. The method may comprise selecting the at least two targets from a plurality of targets. The at least two targets may be selectable based upon their respective target datum thereof. Thereafter, a dual gate surrounding each respective one of the at least two targets may need to be defined, wherein a movement of each dual gate is synchronized with a movement of respective one of the at least two targets corresponding thereto. The dual gate of each respective one of the at least two targets may then be associated with each other to form the group.

Abstract: Radar method and apparatus for detecting small, slow moving targets in the presence of high background clutter that includes a balanced bridge structure to achieve a null balance with the target and background clutter. Radar return signals from background objects as well as the targets are viewed by the radar as a composite single signature return. The invention uses a phase shifter to achieve a null balance even though the background clutter is consists of many components at varying distances from the radar.

Abstract: A wideband adaptive digital beamforming technique for maintaining a high range resolution profile of a target in motion in the presence of jamming utilizes a sequence of adaptively calculated narrowband jamming cancellation weights. The adaptive weights are calculated such that the desired frequency dependent gain is maintained toward the target center. These adaptive weights tend to preserve the range profile quality and low range sidelobes. This technique also tends to eliminate signal cancellation problems as well as adaptive weight modulation effects.

Abstract: A method for improving the determination of tracking and motion analysis information obtained from a set of received data points is presented. The method comprises selecting a determined number of data points for processing, determining at least one cost analysis matrix for each information item included in the selected data points, quantifying each of the at least one cost analysis matrix with regard to a known form; and providing a presentation for each of the quantified matrices. An operator may then discard those presented matrices that provide minimal levels of information and retain those that provide significant levels of information.

Abstract: Circuit for stabilizing the spectral extent of a varying signal containing harmonically related frequency components and having particular utility in the spectral analysis of radar return for the purpose of target identification. The variable signal is written into a storage device at a fixed rate and read out with a variable time compression which is controlled by a discriminator circuit that is connected through a filter to receive one of the harmonic frequency components of the storage device output signal. Also included is signal conversion for digital storage with analog input and output signals.

Abstract: An improved radar signature evaluation apparatus for measuring and evaluating the radar signature for an aircraft, missiles, and other vehicle. The radar signature apparatus includes an instrumentation system for generating radar cross section data for the vehicle being evaluated and a computer for processing the radar cross section data and a printer for printing various plots derived from the radar cross section data.

Abstract: A system for determining the scan type of a signal, such as a radar signal, includes a scan detector, a transformer (e.g., an FFT algorithm), a correlator, and a decision block. The signal is received and processed by the scan detector. The scan detector provides an envelope signal, representing the scan type of the received signal. The envelope signal is transformed, typically from a time domain signal to a frequency domain signal, by any of several processes including a Fourier transform, a Laplace transform, an FFT, or a DFT. The transformed envelope signal is compared to several scan data sets by the correlator. Each scan data set represents a particular scan type. If the decision block determines that the comparison between the transformed envelope signal and a scan data set meets (or exceeds) a degree of similarity, the scan type of the received signal is determined to be the scan type of that scan data set.

Abstract: This invention relates to an object recognition apparatus. This apparatus comprises an antenna which emits transmission beams toward a plurality of directions; a receiving circuit which receives reflected signals of the transmission beams from predetermined directions; a distance and direction calculation circuit which calculates distance and direction to objects reflecting the transmission beams based on the transmission beams and the reflected signals; an object pattern storage unit which stores range direction patterns of reflected signals obtained in advance with respect to predetermined objects; an object recognition circuit which compares range direction patterns of the reflected signals received by the receiving circuit with respect to the predetermined directions, with the range direction patterns stored in the object pattern storage unit, and which recognize that a pair of reflected signals from two neighboring directions are signals reflected by the same object.

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: In a system for estimating the launch point of a missile, Doppler shifted signals reflected from the missile as it travels from its launch point are used in a Kalman filter to estimate the missile position, velocity and acceleration, in earth centered fixed coordinates. The coordinate system is rotated to a rotated earth fixed (REF) coordinate system in which the X-axis passes through the estimated missile launch point and the Z-axis is made parallel to the missile azimuth as represented by the missile velocity determined by the Kalman filter. The error in the downrange component of the missile launch point is then reduced to a minimum in the REF coordinate system using a square root information filter. The coordinate system is then rotated to a second rotated earth fixed coordinate system in which the X-axis passes through the updated launch point position and the Z-axis is positioned at 45 degrees from the missile azimuth.

Abstract: Circuitry and technique for improving the analysis of a signal, such as radar return, by eliminating the effects of frequency variations of the carrier and thereby stabilizing the modulation spectrum. This is accomplished by tracking the carrier frequency and using it as a reference signal for translating the carrier frequency in the radar return to zero frequency.

Abstract: A semantic attractor memory uses an evolving neural network architecture and learning rules derived from the study of human language acquisition and change to store, process and retrieve information. The architecture is based on multiple layer channels, with random connections from one layer to the next. One or more layers are devoted to processing input information. At least one processing layer is provided. One or more layers are devoted to processing outputs and feedback is provided from the outputs back to the processing layer or layers. Inputs from parallel channels are also provided to the one or more processing layers. With the exception of the feedback loop and central processing layers, the network is feedforward unless it is employed in a hybrid back-propagation configuration. The learning rules are based on non-stationary statistical processes, such as the Polya process or the processes leading to Bose-Einstein statistics, again derived from considerations of human language acquisition.

Abstract: A radar apparatus comprises a signal transmitter device that transmits a signal, a scanner that two-dimensionally scans a target object using the signal transmitted from the signal transmitter device by engaging in longitudinal oscillation and lateral oscillation, a signal receiver device that receives a reflection signal of a signal transmitted via the scanner and a control device that controls a longitudinal oscillation signal and a lateral oscillation signal used to oscillate the scanner longitudinally and laterally in correspondence to the length of time over which a scanning observation is performed through a two-dimensional scan.

Abstract: In a method for operating a rotating synthetic aperture radar system that works with pulse frequency or in FM-CW operation in order to detect, penetrate and evaluate objects that are located vertically below the helicopter carrying the ROSAR device, pixels are determined using their own specific doppler histories.

Abstract: A target recognition system and method wherein only target amplitude data, i.e., coherent A-scan data, is interrogated at each of a plurality of range resolution cells along the radar line of sight path for target recognition. Target aspect angle is ignored within the angular segmentation of the feature library without degrading classification performance. Observed signature characteristics are collected at various aspect angles and through unknown roll, pitch and yaw motions of each anticipated target and provided to a neural network as training sets. The neural network forms feature vectors for each target class which are useful for valid classification comparisons in all sea states, especially in calm and littoral waters. These feature vectors are useful for valid classification comparisons over at least 30 degrees of target aspect angle.

Abstract: The invention relates to a method for measurement of the radar target cross section of an object with both moving and fixed parts, which method comprises a first measurement with high frequency resolution, from which information can be extracted on modulations in the signal received that derive from moving parts of the object and fixed parts of the object respectively. The invention is characterized in that the method comprises a second measurement with high range resolution, and filtering of the measuring result obtained from the second measurement, which filtering is performed around a certain frequency that is obtained by means of the measuring result from the first measurement. The first measurement is preferably given a high frequency resolution in that it is performed with a narrow-band waveform, and the second measurement is suitably given a high range resolution in that it is performed with a broadband waveform.

Abstract: A method and system for real-time tracking of objects are disclosed. A region is repeatedly scanned providing a plurality of images or data sets having points corresponding to objects in the region to be tracked. Given a previously determined track for each object in the region, an M-dimensional combinatorial optimization assignment problem is formulated using the points from M−1 of the images or data sets, wherein each point is preferably used in extending at most one track. The M-dimensional problem is subsequently solved for an optimal or near-optimal assignment of the points to the tracks, extending the tracking of the objects so that a response to each object can be initiated by the system in real-time. Speed and accuracy is provided by an iterative Lagrangian Relaxation technique wherein a plurality of constraint dimensions are relaxed simultaneously to yield a reduced dimensional optimization problem whose solution is used to formulate an assignment problem of dimensionality less than M.

Abstract: A spoken word-producing detector identifies objects by comparing signatures of detected objects with stored signatures of known objects. When the signatures compare, the detector produces stored word sounds associated with the detected object identifications. An annunciator produces the words from pre-digitized human voice sounds. A screen displays the words.

Abstract: A target recognition system and method wherein only target amplitude data, i.e., coherent A-scan data, is interrogated for target recognition. Target aspect angle is ignored within the angular segmentation of the feature library without degrading classification performance. Observed signature characteristics are collected at various aspect angles and through unknown and arbitrary roll, pitch and yaw motions of each anticipated target and provided to a neural network as training sets. The neural network forms feature vectors for each target class which are useful for valid classification comparisons in all sea states, especially in calm and littoral waters. These feature vectors are useful for valid classification comparisons over at least 30 degrees of target aspect angle.

Abstract: The present invention relates to a method for classifying objects detected by a vehicle mounted radar located in front of said vehicle for transmitting a radar microwave signal and for receiving reflexes thereof from objects positioned in front of said vehicle, said melted comprising the steps of: tracking a radar reflex from an object located in front of said vehicle as the calculated distance from said vehicle to said object, as derived based upon the time of flight of said radar reflex, decreases; monitoring changes in the amplitude of said radar reflex from said object is said calculated distance from said vehicle to said object decreases; and classifying said object as an overhead object or a ground level object based upon the said changes in the radar reflex amplitude.

Abstract: A radar system (14, 20, 22) generates a plurality of data points (x, y) representative of the position of a tracked object (48), and a representation of an associated path (50, 60) is formed therefrom. At least one quality measure, and at least one heading measure, of said representation, is calculated corresponding to at least one map coordinate (44). The quality and heading measures are stored in memory as a track map. Data from other tracked objects (58) is used to update the track map (38), resulting a plurality of heading values at associated map coordinates (44) that are representative of a path (42) followed by the tracked objects (48, 58).

Abstract: A radar device operates for emitting a detection wave ahead of a vehicle, and detecting objects in response to echoes of the emitted detection wave. A reflector detecting device operates for detecting reflectors among the objects detected by the radar device. The detected reflectors are located along a road. A reflector-row extracting device operates for, in cases where there are a plurality of rows of the reflectors detected by the reflector detecting device in one side of the vehicle, extracting one from among the reflector rows. A road-shape recognizing device operates for recognizing a shape of the road on the basis of the reflector row extracted by the reflector-row extracting device.

Abstract: The invention relates to a radar station placed on the surface of the earth, and to a radar system comprising at least two such radar stations. The signal-processing equipment of the radar stations is adapted, at each point of time, to calculate probabilities of target positions and radial target velocity in relation to each individual radar station, based on the signals emitted and received by this station. These calculated values are associated over time, giving cumulative probability measures for target positions and radial velocities in relation to each individual radar station. By providing a system of at least two radar stations, it is possible to calculate the position of a target by associating target positions, such as they are perceived by the different radar stations, with each other by an association of characteristic movements of the target. This is done without having to synchronize the stations.

Abstract: An apparatus to determine the three-dimensional location of an airborne platform relative to a target area using two separate antenna assemblies positioned on the airborne platform. The first antenna assembly is adapted to transmit energy downward toward a surface location directly beneath the airborne platform, while the second antenna assembly is adapted to transmit energy forward towards the target area remote from the surface location. A single transmitter is associated with both of the antenna assemblies for transmitting signals toward the surface location and the target area. A receiver coupled to the antenna assemblies receives and detects the signals corresponding to the transmitted energy as reflected by the target area and the surface location. A radar processor is coupled to the receiver and is adapted to determine the range between the airborne platform and the surface location and determine the three-dimensional height of the target area from the detected signals.

Abstract: A weapons detector (12) and method utilizing radar. The system comprises a transmitter (27) for producing an output (14) of frequencies of a set of self-resonant frequencies of weaponry; an antenna (28) directing the transmitter output toward locations potentially having weaponry and collecting backscattered signals (15); a receiver (29) receiving the backscattered signals (15) and operating over a range of the self-resonant frequencies; and a signal processor (30) for detecting the presence of a plurality of the self-resonant frequencies in the backscattered signals (15). Accuracies of greater than 98% can be obtained at distances, preferably between 4-15 yards. The weapons detector (12) is capable of detecting metal and non-metal weapons (16) on a human body (13) in purses, briefcases and under clothing; and discerning weapons (16) from objects such as belt buckles, coins, keys, calculators, cellular phones.

Abstract: A method for procession radar signals for a radar arrangement which is moving in relation to its environment, in particular a road vehicle radar due method include analyzing a plurality of object traces formed by objects to be detected, to determining a current moving direction, and, in response to a deviation of this moving direction from the alignment of the radar arrangement, correcting the object angle determined when detecting the objects within the scope of the angular resolution of the radar arrangement on the basis of the determined deviation, and relating it to the moving direction.

Abstract: A spoken word-producing detector identifies objects by comparing signatures of detected objects with stored signatures of know objects. When the signatures compare, the detector produces stored word sounds associated with the detected object identifications. An annunciator produces the words from pre-digitized human voice sounds. A screen displays the words.

Abstract: A device to detect the presence of a target material comprising a source module and detector module. The source module includes a generator to producing a source signal corresponding to a characteristic frequency of the target material. The detection nodule detects a location of the target material wherein the detection module detects an interference signal generated between the source signal and a signal generated by target material caused by exposure to the source signal. The device uses frequencies between 10 MHz and 1.

Abstract: A method and system for real-time tracking of objects is disclosed. A region is repeatedly scanned providing a plurality of images or data sets having points corresponding to objects in the region to be tracked. Given a previously determined track for each object in the region, an M-dimensional combinatorial optimization assignment problem is formulated using the points from M−1 of the images or data sets, wherein each point is preferably used in extending at most one track. The M-dimensional problem is subsequently solved for an optimal or near-optimal assignment of the points to the tracks, extending the tracking of the objects so that a response to each object can be initiated by the system in real-time. Speed and accuracy is provided by an iterative Lagrangian Relaxation technique wherein a plurality of constraint dimensions are relaxed simultaneously to yield a reduced dimensional optimization problem whose solution is used to formulate an assignment problem of dimensionality less than M.

Abstract: A transmission wave is applied to a predetermined range in a width-wise direction of a vehicle. Objects ahead of the vehicle are recognized on the basis of reflected waves resulting from reflections of the transmission wave. Calculation is made as to a position of each of the objects and also a lane-sameness probability for each of the objects that the object and the subject vehicle are on a same lane. Object information pieces corresponding to the respective objects represent the calculated positions of the objects and the calculated lane-sameness probabilities for the objects. In cases where at least two objects become substantially equal in position, the two objects are recognized as a single object. One is selected from the two objects which relates to a calculated lane-sameness probability equal to or higher than a predetermined value. The single object takes over an object information piece corresponding to the selected object.

Abstract: A target recognition system and method wherein only target amplitude data, i.e., coherent A-scan data, is interrogated for target recognition. Target aspect angle is ignored within the angular segmentation of the feature library without degrading classification performance. Observed signature characteristics are collected at various aspect angles and through unknown and arbitrary roll, pitch and yaw motions of each anticipated target and provided to a neural network as training sets. The neural network forms feature vectors for each target class which are useful for valid classification comparisons in all sea states, especially in calm and littoral waters. These feature vectors are useful for valid classification comparisons over at least 30 degrees of target aspect angle.

Abstract: The system and method for calibrating a signal detection threshold circuit is used in a radio frequency (RF) receiver, such as a in an early warning radar (EWR) system, in which a signal detection threshold circuit rejects signals below a predetermined threshold setting and prevents noise signals from causing false alarms. The system and method include setting an initial threshold setting and receiving noise signals in one or more channels. A threshold comparison circuit rejects noise signals below the threshold setting, and a pulse repetition frequency (PRF) detection circuit detects noise pulses above the threshold setting and determines the PRF. An automatic threshold determiner and setter determines whether the PRF has reached a predetermined frequency (e.g., 400 kHz) and lowers the threshold setting until the predetermined frequency is reached. When the predetermined frequency is reached the threshold setting is stored as a noise measurement.

Abstract: The present invention is embodied in an apparatus, and related method, for detecting and recognizing an object in an image frame. The object may be, for example, a head having particular facial characteristics. The object detection process uses robust and computationally efficient techniques. The object identification and recognition process uses an image processing technique based on model graphs and bunch graphs that efficiently represent image features as jets. The jets are composed of wavelet transforms and are processed at nodes or landmark locations on an image corresponding to readily identifiable features. The system of the invention is particularly advantageous for recognizing a person over a wide variety of pose angles.

Abstract: An image processing system and method. In accordance with the inventive method, adapted for use in an illustrative image processing application, a first composite input signal is provided based on plurality of data values output from a sensor in response to a scene including a target and clutter. The composite signal is processed to provide a plurality of tap weights. The tap weights are generated by the matrix of data values which is first filtered by a wavelet transform to provide a set of coefficients. The coefficients are sparsened to provide a sparse matrix. The sparse matrix is then inverse wavelet transformed to provide the tap weights. Finally, the tap weights are applied to the composite signal to yield a clutter reduced output signal. In the illustrative implementation, the matrix is a covariance matrix. However, a method for implementing the teachings of the invention in the data domain is also disclosed.

Abstract: A vehicle follow-up control apparatus includes a distance sensor sensing an actual vehicle-to-vehicle distance from a controlled vehicle to a preceding vehicle, a vehicle speed sensor sensing an actual vehicle speed of the controlled vehicle, and a controller for calculating a desired vehicle speed to be achieved in the controlled vehicle. The desired vehicle speed is calculated in accordance with the actual vehicle-to-vehicle distance, the relative speed and a control gain which is adjusted in accordance with the relative speed.

Abstract: The present invention is in general related to tracking of multiple targets by means of measurements by various sensors. In particular the invention provides procedures for track initiation during multiple target tracking by means of measurements from passive sensors. The invention defines a quality measure for each tentative new target, by which the tentative targets are sorted and selected. The calculation of the parameters of possible targets and their covariance are preferably performed in a recursive manner. The track initiation comprises the steps of creating strobe tracks, calculating strobe track crosses, selecting a strobe track cross as a probable target and creating a target track.

Abstract: A computationally efficient method for calculating near-optimal solutions to the three-objective, linear control allocation problem is disclosed. The control allocation problem is that of distributing the effort of redundant control effectors to achieve some desired set of objectives. The problem is deemed linear if control effectiveness is affine with respect to the individual control effectors. The optimal solution is that which exploits the collective maximum capability of the effectors within their individual physical limits. Computational efficiency is measured by the number of floating-point operations required for solution. The method presented returned optimal solutions in more than 90% of the cases examined; non-optimal solutions returned by the method were typically much less than 1% different from optimal and the errors tended to become smaller than 0.01% as the number of controls was increased.

Abstract: The present invention is in general related to target type estimation in target tracking systems. The invention enables a low complexity estimation of target type, using, e.g. ESM sensor data, by the introduction of an ambiguity restoring procedure in certain likelihood calculations. The invention further enables the systematic use of target type probability information in the calculation of strobe track crosses and their associated quality which is particularly useful for deghosting purposes. Methods for utilisation of target type probability information in the processes of strobe tracking, association, track quality evaluation and multiple hypothesis tracking are also disclosed.

Abstract: Disclosed is a method and apparatus for improving airborne vehicle tracking and guidance systems by reducing boresight error induced by polarization of the RF energy impinging on the vehicle radome. The radome wall is formed with a taper which gradually increases from the base near the vehicle antenna to the tip according to a disclosed formula which accounts for frequency, incidence angle, look angle, and the dielectric constant of the radome material. This taper of the radome minimizes the crossplane boresight error component magnitude which is polarization sensitive and produces a polarization insensitive inplane boresight error component. Also disclosed is a method of electronically compensating such radomes for boresight error where the radome boresight error data accumulated during testing is digitized and processed for compensating data in the vehicle electronic system to provide compensated tracking data for the vehicle guidance system.

Abstract: A dangerous driving conditions warning system for a vehicle such as an automobile is described. The warning system captures signals from two or more devices in an automobile, such as speedometer, distance measuring device, and airbag, and conveys the signals to a decision circuit which determines whether a dangerous driving condition exists and outputs an activation signal upon detecting a dangerous condition. The activation signal is sent to and activates an indicator such as a warning light or loud audible warning. The warning indicator alerts a trailing vehicle and other vehicles near the vehicle equipped with the warning system of the existence of one of various conditions warranting caution, a reduction in speed, or a veering or turn.

Abstract: A method for tracking a target having substantially constrained movement utilizes the steps of determining constrains for movement of the target, obtaining information on movement of the target, and predicting that the target will continue to move upon a route segment after the target has begun to move thereupon. The constraints are made up of a plurality of separate alternate route segments. Predicting that the target will continue to move upon the route segment upon which it is previously moving facilitates targeting, intercept and intelligence with a substantial degree of reliability, particularly when continuing information, such as radar returns, is not available.

Abstract: A Radon transform based method that provides for target azimuth aspect estimation and target shape measurement. A Radon transform is applied to a binary (N×N pixels) target chip to extract target features that are then used to measure length, width, and diagonal features of the target. In parallel, these features are used to estimate the azimuth aspect angle, or size, of the target. The method is effective in discriminating targets from clutter. The method is also very time efficient and highly flexible in its operation because the features can automatically account for any target rotation or shift. The present invention also provides for a target acquisition system that employs the Radon transform based method for target azimuth aspect estimation.

Abstract: Provided is a radar apparatus for use on a vehicle and for detecting one target or two or more targets present in a scan range by scanning the scan range with a radar beam, which has a means for obtaining prior target data by scanning the scan range with the radar beam, a grouping means for carrying out grouping of the prior target data according to a predetermined condition to obtain group data, and a target recognition means for identifying the group data and prior target data remaining without being grouped, as detection data corresponding to respective targets and carrying out recognition of each target corresponding to each detection data. The grouping means makes provision of a plurality of predetermined conditions, selects one condition or two or more conditions according to position information of prior target data to be grouped, and carries out the grouping based on the condition(s) selected. This radar apparatus for use on the vehicle can accurately perform the grouping of point data.

Abstract: The invention relates to a method for measurement of the radar target cross section of an object with both moving and fixed parts, which method comprises a first measurement with high frequency resolution, from which information can be extracted on modulations in the signal received that derive from moving parts of the object and fixed parts of the object respectively. The invention is characterized in that the method comprises a second measurement with high range resolution, and filtering of the measuring result obtained from the second measurement, which filtering is performed around a certain frequency that is obtained by means of the measuring result from the first measurement.

Abstract: Methods of associating a first target track and one of a group of target tracks measured by a radar system, in which the first target track is compared with each of the target tracks in the group of target tracks based on movement between two selected target positions, one in each of the two target tracks. Predetermined maximum numbers of changes in target parameters such as course and speed are assumed to have been able to take place during the movement, and a target parameter for the two positions is allowed to vary while other target parameters are kept constant. A possible range for the varying parameter is determined that is consistent with movement between the two positions, and if a measured value of the varying parameter lies within the range, target tracks are associated with each other.

Abstract: A radar processing system is disclosed with an improved cluster target resolution capability. The invention provides a system and method for processing radar returns and generating first and second contiguous range/doppler cells. Within the cells, first and second dichotomous angle measurements corresponding to radar returns in the first and second contiguous range/doppler cells are derived. An adaptive threshold is then applied to the angle measurements to determine whether the first and second measurements correspond to first and second targets in the first and second range/doppler cells respectively.

Abstract: Stealthcraft are detected by illuminating backgrounds with narrow radar or sonar beams and monitoring this background illumination for the changes that result when these beams are absorbed by such targets, and are ranged by triangulation using two such beams.

Abstract: The present invention relates to a method of detecting and classifying objects using radar. The method means that a broadband radar signal comprising wavelengths that coincide with characteristic lengths of targets to be detected and classified is transmitted. Further, a returned echo signal is received and analysed, at which a signal analysis in a combined time-frequency domain is used, which comprises determining characteristic frequencies in the signal return and their mutual time relations. Finally, a comparison with the corresponding stored values of an analysis of possible targets is performed.

Abstract: In an air traffic control radar system, a processor is described for correlating primary target data received from a target with a target report and a target track, wherein the processor has a search acquisition time that is adapted to the distance of the target from the radar site. The search acquisition time is shorter for more distant targets. The processor can employ a shorter cycle time (time quantum) to establish a correlation between target data and target reports than would otherwise be possible with conventional fixed search acquisition times. The average total dwell time may be reduced while complying with the mandated maximum processing time for more difficult radar reports.

Abstract: A search radar including the improvement of apparatus for enhancing the estimation of the target angle within a search scan of the radar is disclosed. More specifically, the improvement apparatus utilizes the generated scan angles and target amplitude measurements correspondingly associated therewith to generate intermediate signals which are representative of the natural logarithm of the target amplitude measurements plus the square of the corresponding scan angle multiplied by a predetermined constant. For each search scan, the apparatus computes separately signals representative of the moments of: the scan angles, the squares of the scan angles, the products of the scan angles and corresponding intermediate signals, and the intermediate signals. In turn, the apparatus operates on the computed moment representative signals in some prespecified mathematical relationship to effect an optimum estimation for the target angle in each search scan of the radar.