Abstract: An efficient receiver system (80) adapted for use with a pulsed radar system. The receiver system (80) includes a first circuit (82) for receiving a first signal and providing a second signal in response thereto. A second circuit (96) compares the second signal to a predetermined sequence (98) and provides a compare signal in response thereto. A third circuit (104) stores information pertaining to the second signal in response to the compare signal. A fourth circuit (92) generates receiver system instructions based on the stored information. In a specific embodiment, the second signal is a digital signal and the sequence is a digital sequence. The pulsed radar system includes a circuit for receiving and collecting data during a first dwell and for processing the data during a subsequent dwell. An inter-dwell time interval exists between the first dwell and the second dwell. The first, second, third, and/or fourth circuits (82, 96, 104, and/or 92) operate during the inter-dwell period.

Abstract: A target detecting device which measures the range to the target and genees a variable d.c. voltage that is a function of the range. The range voltage is then applied to a time delay computer, along with range rate voltage, to permit a time delay computation which is a function of both the distance to the target and the missile-target closing velocity.

Abstract: An image guided weapon system employing passive optical terminal guidance d method which provides the precision strike capability without requiring the use of a designator or the presence of an additional designator aircraft, which can operate through the weather, which allows rapid attack of multiple targets, and which does not require any aircraft to remain in the target area after a weapon has been launch. A target area is designated and an image of the target area is generated. An aimpoint within the target area is selected and GPS coordinates of the aimpoint are determined. An image template is generated using flight orientation data, the image of the target area, and GPS coordinates of aimpoint. Image processing software creates an image template which is downloaded to a weapon. The weapon's seeker generates seeker images which are compared to the image template.

Abstract: The recoverable airborne instrument platform accurately determines its present position and uses this data to execute a predetermined flight plan and ultimately guide its descent to a predetermined landing site. This is accomplished by installing the instrument package payload in the aerodynamic exterior housing of the recoverable airborne instrument platform, which has a plurality of moveable control surfaces thereon to autonomously control the altitude, attitude and flight path of the recoverable airborne instrument platform. A navigation circuit contained within the aerodynamic housing determines the geographic location of the recoverable airborne instrument platform as well as the location of at least one predetermined recovery site. The determined position data is used to dynamically calculate a flight path which allows the guidance control circuit to both execute a predetermined flight plan and controllably descend the recoverable instrument platform to a selected predetermined recovery site.

Abstract: In a process for identifying an incorrectly measuring sensor which is part of a sensor arrangement on a spacecraft, external directional vectors are measured, relative to external objects, such as the earth, the sun or selected stars, or to external field vectors, such as the earth's magnetic field. Based on actual time and space coordinates of the spacecraft, respective actual external directional vectors are calculated with respect to an inertial system of coordinates, and the angles between these vectors are determined. These angles are compared with corresponding angles which exist between the directional vectors measured by a function of the sensor arrangement relative to a spacecraft-fixed system of coordinates. Based on this comparison a sensor which may measure incorrectly can be identified reliably.

Abstract: Circuitry for adjusting the resonant frequency of an Yttrium-Iron-Garnet (YIG) filter in the first local oscillator of a receiver carried on a guided missile is shown to include the combination of a crystal oscillator which produces a pilot signal for tuning the YIG filter to a corresponding resonant frequency and a frequency adjusting arrangement for offsetting the resonant frequency of the YIG filter by a predetermined amount.

Abstract: A means for identifying a particular range and Doppler shift signal in the field of view of a moving radar antenna which determines azimuth angle to this range-Doppler signal relative to the antenna by determining the phase difference between said signal as processed through two channels each fed by antennas displaced in a horizontal direction with respect to the axis of the antenna system.

Abstract: A monopulse system generates sum (.SIGMA.), elevation difference (.DELTA..sub.EL), azimuth difference (.DELTA..sub.AZ), and double difference (.DELTA..sub..DELTA.) signals, and generates a covariance matrix. The covariance matrix is decomposed to produce at least the principal eigenvector. The location or angular direction within the main beam of a single target is determined from the real component of the quotient of elements of the principal eigenvector, by the use of a look-up table. In another embodiment of the invention, the eigenvalues are generated from the covariance matrix, and the number of significant eigenvalues determines the number of targets within the main beam. If a single target is found, its location is found as described above. If two targets are found in the main beam, the locations of the two targets are determined by a closed-form solution of quadratic equations.

Abstract: A system and method for imaging target detection includes scanning a target area to produce an image of the target area and discriminating a target by identifying image pixels of similar intensity levels, grouping contiguous pixels with similar intensity levels into regions, calculating a set of features for each region and qualifying regions as possible targets in response to the features; discriminating the background by identifying image pixels of similar intensity levels, grouping contiguous pixels of similar intensity levels into regions, calculating a set of features for each background region and qualifying background regions as terrain characteristics in response to the features and analyzing the qualified terrain characteristics and qualified target candidates to determine and prioritize targets.

Abstract: Two new homing guidance laws, designated as proportional Guidance (PROGUIDE) and Augmented Proportional Guidance (Augmented PROGUIDE), have been developed for use against non-maneuvering and maneuvering targets, respectively. These guidance laws are the solutions of linear-quadratic regulator control problems and minimize deviations from the collision triangle over the entire period of homing flight, thereby indirectly minimizing miss distance. In contrast to proportional navigation (PRONAV), these algorithms command the achievement of angular acceleration instead of linear acceleration and there is a significant advantage in doing so.

Abstract: A process and a system for selecting a pulse repetition frequency that causes clutter pulse repetition frequency lines from the negative carrier frequency and from the clutter harmonic frequencies to lay on top of clutter pulse repetition frequency lines from the positive carrier frequency. A pulsed Doppler radar receiver of the system has one or more channels each comprising of a radio frequency input section for receiving a radio frequency carrier. Following the radio frequency input section are one or more serially arranged intermediate frequency sections that terminate in a last intermediate frequency section. The last intermediate frequency section is followed by analog-to-digital conversion and down-conversion to baseband in-phase and quadrature channels. In-phase and quadrature data from the in-phase and quadrature channels is processible by a computational system to detect and track a target in the presence of clutter.

Abstract: Synthetic discriminant function automatic target recognition system augmented by LADAR combines, through the synthetic discriminant function (SDF), the active LADAR data of the potential target object with the passive infrared imagery of the target and background. In doing so, the system not only recognizes and classifies the target but also provides the range profile of the target object by analyzing the amplitude of the reflected return signal when appropriate. The live target scene imagery in passive infrared is detected, filtered and subsequently complex multiplied with pre-existing synthetic discriminant function to produce a two-dimensional cross-correlated surface. Analogous process is performed on the active LADAR range and intensity images of the live target scene with corresponding pre-existing synthetic discriminant function for the same target pose and scale as in the passive infrared correlation step.

Abstract: A system for measuring the roll angle of a rotating projectile. The system includes a transmit system mounted on the projectile. The transmit system has a linearly polarized transmit antenna system, a first transmitter coupled to the transmit antenna system for transmitting a first transmit signal at a first frequency, and a second transmitter coupled to the transmit antenna system for transmitting a second transmit signal at a second frequency. The first frequency is different from the second frequency, and the first and second transmit signals are in phase coherency. The system further includes a receiver system located remotely from the projectile. The receiver system includes a linearly polarized receive antenna system for receiving the first transmit signal and the second transmit signal. A first receiver section is provided for receiving and downconverting the first transmit signal to provide a first receiver signal.

Abstract: A land mine arming/disarming system is provided in which a satellite or other airborne vehicle may remotely arm and/or disarm land mines via signals transmitted through atmospheric free space. In such a manner, land mines are less of a health hazard when conflict situations are not present.

Abstract: A method for guiding a missile to a target. The method includes the step of providing a surface-based radar system having an electronically beam steerable antenna system adapted for continuous mechanical rotation about an axis. During a pre-terminal, semi-active missile homing guidance phase, the beam produced by the antenna system is electronically rotated by the antenna system in a direction counter to the direction of the mechanical rotation of the antenna system to thereby increase radar system illumination time on the target. Further, during the increased illumination time, the beamwidth of the surface-based radar system beam is increased. During, a subsequent terminal, active homing missile guidance phase, guiding the missile to the target with the pre-terminal, semi-active missile homing guidance phase using the surface-based radar system and establishing an angular orientation for a missile-borne antenna system at the commencement of the terminal, active missile homing guidance system phase.

Abstract: This radar with a wide instantaneous angular field and a high instantaneous angular resolution, in particular for a missile homing head, includes essentially:a transmitting antenna with a relatively wide radiation pattern, transmitting a quasi-continuous wave;a receiving antenna including a plurality of radiating elements;means for formation of beams associated with said receiving antenna, to achieve a linear combination of the signals from the various radiating elements of said receiving antenna, in order to obtain a group of simultaneous reception beams allowing the instantaneous scanning of the airspace covered by said transmitting antenna.

Abstract: Tracking means for establishing a line-of-sight between a control point to which the second craft is being guided and tracking the line-of-sight to follow the second craft and deriving a signal .sub.a representing the rate of rotation of the line-of-sight about the control point; monitoring means for deriving a signal representing the displacement e of the first craft from the line-of-sight, a signal representing the range R.sub.m between the first craft and the control point, and a signal representing the rate of change R.sub.m of the range R.sub.m, presetting means for providing a signal representing a positive quantity k; and a computer for deriving signals representing .sub.c, .sub.c, and k to satisfy the equation ##EQU1## and minimize the difference -.sub.a, k being initially set equal to k.sub.1 ; control means for deriving from the representations provided by the computer a signal representing f(e)+R.sub.m .sub.c +2R.sub.m .sub.

Abstract: A method of guiding an object by means of a radar information field, wherein a field is created comprising a beam which has a generally annular cross sectional region defining a central null in the field, controlling the beam so that the null is directed towards a destination or target, and positioning said object in or at a defined position relative to the null, said object including an antenna and receiver means responsive to the signal strength difference between the annular region of the information field and the null in order to guide the object to the destination or target.

Abstract: A launch aircraft launches a bomb at a target and uses a radar to transmit a predefined waveform at the bomb and target. The bomb incorporates a transponder that frequency shifts the transmitted waveform and illuminates the target with a shifted waveform having a null at the center of its beam pattern. The initially transmitted waveform and frequency shifted waveform are reflected from the target and are received by the radar. The received signals are processed to generate a correction signal that is a function of the offset between the null of the frequency shifted waveform and the target location. The correction signal is transmitted to the bomb and is processed therein to correct the flight path of the bomb toward the target.

Abstract: A method for calibrating the radar system includes the steps of: replacing stored statistically generated "average" error correction coefficients with error correction coefficients personal to a missile under test. More particularly, stored in the missile's memory are: (a) first personalized error correction coefficients generated in response to test signals produced internal to the missile and injected into a monopulse arithmetic unit for the missile's receiver/processor; and (b) a second set of personalized error coefficients generated in response to test signals external to the missile and injected through the missile's antenna to the receiver/processor. The missile includes a radio frequency (R.F.) energy test signal generator for performing a test during the missile's flight to determine "in-flight" personalized error correction coefficients. The test is performed in-flight by injecting the R.F.

Abstract: Tracking means for establishing a line-of-sight between a control point towards which the second craft is being guided and tracking the line-of-sight to follow the second craft and deriving a signal .theta..sub.a representing the rate of rotation of the line-of-sight about the control point; monitoring means for deriving a signal e representing the displacement of the first craft from the line-of-sight, a signal representing the range R.sub.m from the control point to the first craft and a signal representing the rate of of change R.sub.m of the range R.sub.m ; ranging means for deriving a signal representing the range R.sub.t from the control point to the second craft and a signal representing the rate of change R.sub.t of the range R.sub.t ; a computer for deriving representations of .theta..sub.c, .theta..sub.c and .theta..sub.c which satisfy the equation.sub.c =-2.theta..sub.c.sup.3 -3.theta..sub.c (R.sub.t /R.sub.t)where the difference .theta..sub.c -.theta..sub.

Abstract: The invention relates to a phased array antenna by means of which, besides normal radar transmissions, also a guidance of a number of semi-active homing missiles towards a number of targets can be effected. The main problem to be solved here is that a rear-reference signal for each missile remains present to a sufficient extent also during the periods covering normal radar transmissions. The invention solves this problem by transmitting rear-reference signals for all missiles deployed simultaneously with radar transmitter signals.

Abstract: A coherent radar receiver that has pulse-to-pulse coherence using an unlocked voltage controlled oscillator, such as a Gunn voltage controlled oscillator. The present invention is a W-band, for example, bistatic receiver that uses a scanning sum channel antenna to scan the target, a downconverter for downconverting received alternating sum and difference pulse echoes from the bistatic illuminator to provide video signals, and processing circuits for processing the downconverted the video signals to precisely locate the null position on the target. A Fourier transform circuit, magnitude detector and a peak detection and centroid circuit are used to generate a voltage frequency control output signal that is applied to the voltage controlled oscillator or local oscillator that controls its frequency. An angle estimation algorithm is used that processes the video signals to locate the null offset from the center of a scan pattern generated by the antenna.

Abstract: An arrangement for coordinating positional and angle information made on separate relatively moving platforms, such as aircraft, having independent coordinate systems, uses measurements of a common reference made on both platforms. The measurements are transmitted to a common location. Measurements made at a first time are processed to determine two of three coordinate transformation angles. After a period of time, a second set of measurements is used to determine the third coordinate transformation angle. In a particular embodiment of the invention, the direction of motion of one of the platforms is controlled to be orthogonal to a coordinate axis of the other platform. When the coordinate transformation is determined, it can be used to coordinate or align navigation instruments, weapons, or the like. In one embodiment of the invention, a missile is directed toward a target, in a situation in which the target is viewed from the missile and another moving vehicle.

Abstract: A radar system in which a frequency agile synthesizer is used to provide rapid frequency shifts and in which measures are taken to maintain phase coherency. The system is fully coherent such that all signals are derived from a common source and are capable of high pulse repetition rates in excess of 1 MHz. There are no inherent transmit duty cycle restrictions and the system is able to transmit complex phase and frequency modulated waveforms. A frequency interleaving scheme is used to resolve range ambiguities at high pulse repetition frequencies and the use of a complementary phase coding scheme allows a high range resolution processing with the transmitted waveforms.

Abstract: The disclosure relates to a low cost and highly accurate precision guided system suitable for use in conventional aircraft launched bombs. The system includes a kit mounted upon the nose of the conventional bomb which replaces the conventional fuse disposed in a fuse well, the kit including guidance electronics controlling a self-contained jet reaction device and GPS P-code receiver electronics. The bombs are readied for discharge by signals broadcast from the aircraft into the bomb bay which transfer initial GPS data and commence operation of a gas generator which powers the jet reaction device.

Abstract: A maneuver detector and processing method for use in target trackers employed in weapon guidance systems, and the like, that employs multidimensional measurements and a set of inertial coordinate systems. The maneuver detector and processing method are implemented as follows. Time-delayed target position and velocity estimates of the target are maintained in a history file. These estimates are continuously updated, in that they are transformed 24 into intermediate north, east, down (NED) range Cartesian coordinate systems by correcting for aircraft motion. For each measurement time, the histories are used to predict the position and velocity of the target in an "observation-relative" inertial coordinate system aligned with the line-of-sight to the target. The error between the prediction and observation is calculated and used with the measurement accuracies to calculate a maneuver probability.

Abstract: A radar system is provided to track radar energy reflected by a point on the target different from the centroid of a target's radar reflected energy. The radar system includes a target angle/range tracking system and a target energy monitoring/range tracking system. During a first mode of operation, the target angle/range tracking system tracks the centroid of the target's reflected energy; and, the target energy monitoring/range tracking system monitors the strength of energy reflected from points, or regions along the body of the target different from the centroid reflected energy producing region. When the signal strength to noise ratio (i.e., S/N ratio) from a reflection at one of the monitored points along the target exceeds a predetermined level indicating detection of a secondary reflector along the body of the target, a second operation mode commences.

Abstract: A radar system having a transmitter for transmitting a series of radio frequency (RF) pulses with sequential, incrementally changing carrier frequencies. A receiver receives energy from multiple scattering points of an object reflecting such transmitted RF pulses. The received energy from each one of such scattering points includes a series of radio frequency (RF) pulses corresponding to the transmitted pulses delayed in time, .tau., from the transmitted pulses an amount proportional to the range to such scattering point and shifted in frequency from the carrier frequency an amount proportional to the velocity of such scattering point. The receiver includes a heterodyning section, responsive to a range tracking error signal, .epsilon..sub.R, and a velocity tracking error signal, .DELTA..sub.VEL, for producing a series of pulsed signals for each one of the scattering points. Each one of the pulsed signals for any given scatterer sequentially changes in phase, .phi., at a rate, .DELTA..phi./.DELTA.

Abstract: A radar system includes a radar receiver that provides the amplitude and the angular position of a plurality of return signals. A computer forms a test function of amplitudes and angular positions of the plurality of return signals and compares the test function with a threshold value. Returns associated with a test function whose value is equal to or greater than the threshold value are determined to be targets, and those with lesser values are considered clutter.

Abstract: The attitude of a body 12 is determined, or refined, by illuminating it with a direct beam and one or more indirect beams which are reflected from a scattering surface SS, all of the beams being radiated from the same or adjacent sources. The directions of arrival of the beams are determined to allow the attitude to be determined or refined.

Abstract: A probe acquisition and display system is disclosed featuring one simple trol for acquiring, tracking, and instantaneously locking for a missile control radar. The system provides for fast initial target acquisition and re-acquisition in the presence of intentional or unintentional interference. A dual trace oscilloscope display is provided with radar tracking (range) gate and a probe is used to touch a target on the display by a radar operator.

Abstract: A guidance seeker for a spinning projectile defined by its angular momentum vector, comprises a lens system or a millimeter-wave antenna for receiving radiation derived from a target and forming an image of the target. The lens system has a reticle having a pattern of concentric circles nutating about the projectile angular momentum vector such that the received radiation is modulated by the target image as the image moves across the concentric circles. The millimeter-wave antenna generates concentric lobes nutating about the projectile angular momentum vector such that the received radiation is modulated by the target image as the image moves across the concentric lobes. A detector is coupled to the lens system or the antenna for receiving the modulated radiation. The detector is adapted to generate an output in response to the received modulated radiation.

Abstract: The disclosure relates to a low cost and highly accurate precision guided system suitable for use in conventional aircraft launched bombs. The system includes a kit mounted upon the nose of the conventional bomb which replaces the conventional fuse disposed in a fuse well, the kit including guidance electronics controlling a self-contained jet reaction device and GPS P-code receiver electronics. The bombs are readied for discharge by signals broadcast from the aircraft into the bomb bay which transfer initial GPS data and commence operation of a gas generator which powers the jet reaction device.

Abstract: A multi-mode seeker which comprises a stationary antenna and electronic circuitry responsive to signals received by the antenna to cause the antenna to scan a field of view determined by the signals received by the antenna. The seeker has a nose region positioned at the forward portion thereof and an adjunct sensor disposed in the nose region ahead of the antenna. The electronic circuitry includes circuitry for performing a Sum/Delta monopulse processing technique on the signals received by the antenna the Sum/Delta monopulse processing including calculating each of a standard Sum signal, Delta-Azimuth signal and Delta-Elevation signal. The seeker has a boresight axis, the center of the field of view being off boresight, in general. The seeker has a field of regard, the field of regard having plural sectors, each of the sectors having separate predefined compensation.

Abstract: A narrow band receiver is shown to include a double downconversion arrangement wherein the frequency of the second local oscillator is controlled to maintain the frequency of the second I.F. signals at a predetermined value.

Abstract: A system and method that provides for all-weather precision guidance of conventional air-to-surface weapons. The system and method employs a coherent monopulse radar disposed on a launch platform and a noncoherent passive (receive only) radar disposed on the weapon. The synthetic aperture radar generates a synthetic aperture radar monopulse map of an area around the target. The radar is used designate the location of the target, and transmit a sequence of alternating sum and simultaneous azimuth and elevation difference patterns centered on the target. The weapon includes a guidance system and seeker that is responsive to guidance commands transmitted by the synthetic aperture radar. The guidance system and seeker receives reflections of the alternating sum and combined azimuth and elevation difference pattern from the target, and the sum pulse is used by the weapon to acquire and track the azimuth and elevation difference pattern null on the target to fly an optimum trajectory to the target.

Abstract: An improved imaging system. The inventive imaging system (10) is adapted to transmit a plurality of first radar signals at millimeter wave frequencies at an area including an object along with background clutter. The return signals are processed to provide a three dimensional image for applications demanding visibility through fog, haze, smoke and other obscurants. Such applications include enhanced vision for helicopters, ships, buses, trucks, traffic observation stations for an intelligent highway or security cameras for plants and military installations. In a guidance system application, for example, the inventive system would include an electronically scanning antenna (12) to provide range and amplitude signals representative of a target area. The range and amplitude signals (18, 20) are compared to stored signals (26, 30) to create the three dimensional image. The stored signals are selected for comparison based on the dive angle of the missile (28, 32).

Abstract: An underwater maneuverable vehicle is presented which carries an explosive charge and can be used for immediate removal or destruction of various menaces to navigation and other underwater hazards. The battery powered vehicle is air dropped from a platform which carries an imaging lidar system for detection and is operated and navigationally controlled in conjunction with an imaging lidar system. In accordance with an important feature of this invention, an optical lidar downlink is used to control the submerged underwater maneuverable vehicle from an airborne platform. The downlink is pulse spaced modulated. Command signals are secure, and are decoded aboard the vehicle. Control in speed, heading and depth, as well as command detonation are available using this technique.

Abstract: A missile (20) includes a missile body (22) having a propulsion motor (26), a gimballed target seeker (32), and control fins (30) for altering the flight path of the missile (20). The missile (20) has a missile flight control unit (44) which provides an indicator of the launch status of the missile (20) as to whether the missile (20) is launched from a fixed location or from a moving vehicle. The initiation of the guidance of the missile (20) toward a target (60) by the control fins (30) and the guidance law of the missile (20) are established responsive to the launch status indicator.

Abstract: A synthetic aperture radar guidance system adapted for use in a guided missile is described wherein the frequency of the transmitted pulses changes with time with a chirp slope which varies with range. The time between pulses also changes as a function of range. The desired values of the chirp slope and the interpulse interval are computed for all values within a range of interest and stored. Furthermore, the operating parameters of the SAR are changed as the range changes. The time intervals and frequencies are selected to avoid interruption ambiguities and eclipsing. The phase and frequency of the synthesized signal are controlled to adjust for motion of a vehicle on which the SAR is mounted. The SAR is operated in several modes. In a search mode, the beam of transmitted pulses is steered across a mapping area to form a plurality of patches of the mapping area. The patches are combined into one map of the entire area. Each pixel of the map is compared with a target template until a match is provided.

Abstract: A synthetic aperture radar guidance system adapted for use in a guided missile is described wherein the frequency of the transmitted pulses changes with time with a chirp slope which varies with range. The time between pulses also changes as a function of range. The desired values of the chirp slope and the interpulse interval are computed for all values within a range of interest and stored. Furthermore, the operating parameters of the SAR are changed as the range changes. The time intervals and frequencies are selected to avoid interruption ambiguities and eclipsing. The phase and frequency of the synthesized signal are controlled to adjust for motion of a vehicle on which the SAR is mounted. The SAR is operated in several modes. In a search mode, the beam of transmitted pulses is steered across a mapping area to form a plurality of patches of the mapping area. The patches are combined into one map of the entire area. Each pixel of the map is compared with a target template until a match is provided.

Abstract: This invention comprises the use of integral pulse frequency modulation (IPFM) reaction jet controllers for multi-axis precision tracking of moving objects with flexible spacecraft, and vibration suppression. Two sets of position, rate and accelertion command profiles for multi-axis tracking are disclosed: one for a payload initially facing the zenith and the commands based on a pitch-roll sequence; the other for a payload facing the nadir and the commands based on a roll-pitch sequence. The procedure for designing an IPFM controller for tracking a given, inertial acceleration command profile is disclosed. Important elastic modes of a spacecraft are identified according to their spontaneous attitude and rate response to the minimum impulse bit of the thrusters. The stability of the control-structure interaction is shown to be governed by the ratio of the moments of inertia of the flexible to the rigid portions of the spacecraft.

Abstract: A method for guiding a vehicle (30) to a target (28) includes furnishing a first vehicle (20) having a first global positioning system (GPS) receiver (24) fixed to receive global positioning signals from a selected constellation (46) of satellites in orbit above the earth and the second vehicle (30) having a second GPS receiver (32) fixed to receive global positioning signals from the same selected constellation (46) of GPS satellites. The first vehicle (20) locates the target (28) with an onboard sensor (26) and converts the location of the target (28) to the frame of reference of the selected constellation (46) of satellites of the GPS. The first vehicle (20) communicates this target position and the available set of GPS satellites to a navigation system of the second vehicle (30).

Abstract: An automatic target acquisition and tracking system has been developed for a focal plane array seeker. The automatic target acquisition is achieved by three independent target acquisition algorithms, viz., the maximum likelihood classification, the video spatial clustering, and the target-to-interference ratio. Each algorithm operates asynchronously and provides independent target detection results. Target information is then combined hierarchically in a probabilistic fashion and prioritized. The highest priority target is handed off to a dual mode tracker consisting of a minimum absolute difference correlation tracker and a centroid tracker. The dual mode tracker subsequently provides a feedback signal to a proportional navigation system or other guidance/control system for directing the flight path of a munition.

Abstract: Method and apparatus for guiding a projectile to a target in a scene using a scene imaging sensor in which the projectile has a guidance and control system for aiming the projectile. A first tracker analyzes the scene and selects a first track point representative of a target and a first confidence value serving as a reliability measure of the first selected track point. A second tracker analyzes the scene and selects a second track point representing the target and a second confidence value which serves as a reliability measure of the second selected track point. Each of said trackers are constructed and arranged to operate independently in a manner that is substantially statistically uncorrelated with respect to each other. A joint confidence value based on track point proximity, convergence and divergence is generated from the tracker data and a composite confidence index is calculated from the first and second confidence values and the joint confidence value.

Abstract: A processor for an FM/CW sensor divides the sweep periods of the sensor into a number of subsweep intervals, measures the received power within a multiplicity of frequency windows during each of the subsweep intervals, and then performs a spectrum analysis of the power measurements in each frequency window to characterize the reflectors in the corresponding range bins of the FM/CW sensor footprint.

Abstract: An optical RF stereo systems includes multiple remote vehicles, a processing center, and optical RF link systems for transmitting RF signals from remote vehicles to the processing center and for transmitting command and control signals from the processing center to remote vehicles.

Abstract: A radar homing system in a guided missile for intercepting one of a group of targets, such as aircraft flying in formation. Offset circuitry places undesired Doppler target returns outside of the IF filter bandpass frequency of the system. The system is designed to take cognizance of the highest Doppler frequency derived from the targets.

Abstract: An optical RF stereo systems includes multiple remote vehicles, a processing center, and optical RF link systems for transmitting RF signals from remote vehicles to the processing center and for transmitting command and control signals from the processing center to remote vehicles.