Abstract: An attitude sensing apparatus for determining the attitude of a mobile unit is provided that can reliably estimate an alignment angle between a GPS antenna coordinate system and an IMU coordinate system with good accuracy regardless of the magnitude of the alignment angle. Based on observation of the difference between a GPS angular velocity and an IMU angular velocity, an alignment angle estimating section estimates an alignment angle and sensor errors. An alignment angle adder and a sensor error adder cumulatively add and update the estimated alignment angle and sensor errors, respectively. The estimated alignment angle is fed back to an inertia data converter while the estimated sensor errors are fed back to an inertia data correcting section. The apparatus repeatedly performs estimation until the estimated alignment angle gradually approaches a true alignment angle by successively feeding back estimated values to a flow of alignment angle estimation process.

Abstract: A position-adaptive radar method and device for small UAV platforms capable of detecting “leakage signals” that, for example, propagate between two buildings or “leak through” penetrable surfaces such as walls or layers of the ground. The position-adaptive radar comprises a monostatic radar receiver that measures and processes leakage signals and then “self adapts” in position to establish line-of-sight between a mini-UAV platform and an obscuration channel that propagates the leakage signal. This allows a mini-UAV platform to process signals in real-time while gathering intelligence information and locating objects-of-interest that may be embedded within an obscuration channel.

Abstract: Reducing antenna boresight error includes receiving radar pulses reflected from the ground, where pulses are emitted from the antenna of a radar system, reflected by the ground, and received by the antenna. The return pulses carry information about the ground. Measurement indices are established from radar and platform parameters, and a clutter spectrum is generated from the return pulse information. The amplitude of the clutter spectrum is measured at each of the measurement indices. Whether there is an amplitude imbalance is established in accordance with the measured amplitudes. An error estimate describing an antenna boresight error is determined if there is an amplitude imbalance.

Abstract: A radar tracking system for an anti-aircraft, missile, including angle tracking, doppler tracking and range tracking feedback loops operating on sum and difference channels. Fast fourier transform digital filters are used to provide a frequency spectrum of the sum and difference I.F. channels and detection and confirmation algorithms are employed for selecting the F.F.T. target ‘bin’. Adjacent F.F.T. bins are used to simulate a bin centered on the target frequency, shifts of the latter with target/missile acceleration causing frequency errors which are detected by a discriminator and used to control the target I.F. Confirmation of target acquisition is achieved by successive summations of the target bin power the totals being accumulated and compared with upper and lower thresholds. Confirmation and rejection results from total levels outside the thresholds while further accumulation and comparison follow the intermediate condition.

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

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

Abstract: A simple RF system tracks a missile, bullet or artillery round and determines the instantaneous attitude of the spinning projectile while in flight. The system is particularly useful in command-guided weapons systems where line-of-sight is maintained from the launch platform to the target. The system includes a first pair of linearly polarized transmit antennas spaced apart on the projectile for transmitting a signal and a harmonic of that signal. A receiver on the launch platform determines the roll angle and either the yaw or pitch angle from the received signals. To determine the remaining angle, either the receiver samples the received signals ninety degrees out of phase or a second pair of transmit antennas are mounted on the projectile, preferably ninety degrees from the first pair, for transmitting another pair of harmonic signals.

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

Abstract: The invention includes a method and apparatus for planning a mission profile in real time on board a platform or a vehicle dispensed from a platform. In general, the mission planning technique includes ascertaining a plurality of target information, including a target location, a target velocity, and a target location error. This is followed by an autonomous determination of a pattern from the ascertained target information.

Abstract: A system and method of providing situational awareness and weapon targeting is presented. The method includes determining the location of one or more enemy sites and one or more friendly sites. A “Do Not Engage” (DNE) zone is determined around each of the friendly sites and an “Allowable Engagement” (AE) zone is established around each of the enemy sites, wherein none of the AE zones overlap any of the DNE zones. An engagement plan is then determined based on the AE zones and integrity bounds on candidate munitions. The system includes a processing and communications network and a sensor element in communication with the processing and communications network. The system also includes a command control element in communication with the processing and communications network and an operating elements section in communication with the processing and communications network.

Abstract: A dual mode radar seeker comprising a wide-band passive anti-radar antenna system (3) at the rear of a radome (1), operating at relatively low radar frequencies in an amplitude comparison tracking mode, and a high-frequency (W-band) active amplitude-comparison antenna system (5) in the nose of the radome (1) and having a common boresight with the anti-radar system. The active system employs coarse phase shift steering (31, 41) of the antenna ‘beam’ for the transmit and, optionally, also, the receive ‘beam’. The high frequency and the use of phase shift steering both help to keep down the size of the active radar thus enabling it (5, 7, 9) to be positioned far forward in the nose of the radome (1) so as not to obscure the field of the anti-radar system (3).

Abstract: A method for calculating a center frequency and a bandwidth for a radar doppler filter is herein described. The center frequency and bandwidth are calculated to provide radar performance over varying terrain and aircraft altitude, pitch, and roll. The method includes receiving an antenna mounting angle, a slant range, and velocity vectors in body coordinates, calculating a range swath doppler velocity, a track and phase swath bandwidth, and a phase swath doppler velocity. The method continues by calculating a range swath center frequency based on the range swath doppler velocity, calculating a phase swath center frequency based on the phase swath doppler velocity, and calculating a level and verify swath bandwidth based upon the track and phase swath bandwidth.

Abstract: The Multiple-Antenna Jamming System (MAJS) is useful for missile-borne jamming of active protection system radars that operate in close proximity to the frequency band of the missile's radio frequency seeker. The MAJS utilizes multiple receiving and transmitting antennas to reduce shadowing effects due to the transmissive radome. It also channelizes the jamming signals into in-seeker-band and out-of-seeker band signals to synchronize the transmission of jamming signals with the emit-listen pattern of the missile seeker and to eliminate the problem of de-sensitizing the RF seeker from the jammer energy. The in-seeker-band jamming signals are transmitted only concurrently with the missile seeker emissions and any signals emanating from an enemy radar are received only during the listen mode of the missile seeker.

Abstract: A reflected energy detecting device includes a transmitter for transmitting an electromagnetic signal and a receiver for receiving a reflected electromagnetic signal. An antenna may be operatively connected with the transmitter and the receiver for radiating the electromagnetic signal and capturing the reflected electromagnetic signal and the antenna may be movable. A main controller may be provided for controlling operation of the transmitter and the receiver and the movement of the antenna and the reflected energy detecting device may further include at least one platform. The at least one platform may support a remote reflector that is dimensioned and configured to redirect the transmitted electromagnetic signal in a desired direction and a platform controller that is configured to communicate with the main controller and to maintain alignment between the remote reflector and the antenna.

Abstract: A method for calculating a center frequency and a bandwidth for a radar doppler filter is herein described. The center frequency and bandwidth are calculated to provide radar performance over varying terrain and aircraft altitude, pitch, and roll. The method includes receiving an antenna mounting angle, a slant range, and velocity vectors in body coordinates, calculating a range swath doppler velocity, a track and phase swath bandwidth, and a phase swath doppler velocity. The method continues by calculating a range swath center frequency based on the range swath doppler velocity, calculating a phase swath center frequency based on the phase swath doppler velocity, and calculating a level and verify swath bandwidth based upon the track and phase swath bandwidth.

Abstract: A method of guiding a munition to a target transmitting one or more signals is described. The method includes configuring the munition with a radio frequency receiver, an antenna for the receiver mounted such that a main beam of the antenna pattern for the antenna is offset from a line of flight axis of the munition by an angle and configuring the munition to rotate along an axis substantially similar to the line of flight axis of the munition. The method also includes configuring the munition to process signals received at the antenna, wherein heading changes of the munition, the angle of the main beam of the antenna from the line of flight axis, and the rotation of the munition result in the received signals having amplitude variations. Directional corrections are generated for the munition to direct the munition towards the target based on amplitude variations in the received signals.

Abstract: Methods and apparatus for detecting obstacles in the flight path of an air vehicle are described. The air vehicle utilizes a radar altimeter incorporating a forward looking antenna and an electronic digital elevation map to provide precision terrain aided navigation. The method comprises determining a position of the air vehicle on the digital elevation map, selecting an area of the digital elevation map in the flight path of the air vehicle, based at least in part on the determined air vehicle position, and scanning the terrain representing the selected map area with the forward looking antenna. The method also comprises combining the digital elevation map data for the selected map area with radar return data for the scanned, selected area and displaying the combined data to provide a representation of the terrain and obstacles in the forward flight path of the air vehicle.

Abstract: A technique is provided that uses a dual mode seeker (IR and LADAR) for precise target dynamics measurement, which extends stripping to a much higher altitude than ground based radar. Initial results show that this approach works to altitudes in excess of 100 km. Stripping becomes a reliable way to discriminate lighter weight decoys from reentry vehicles at altitudes and ranges consistent with planned divert capabilities for terminal phase missile defense. It is a finding of this invention that the LADAR will improve the spatial resolution by a factor of five over typical missile defense IR seekers using a common aperture. The LADAR provides a 3D angle, angle, range (AAR) image for each laser pulse which is used to extract the precise target state vectors.

Abstract: A method and apparatus for finding a relative direction of received radiation is described. The received radiation is incident upon a window system at an angle and is transmitted therethrough. The magnitude of the transmitted radiation decreases as a continuous function of increasing angle of incidence, known as Fresnel transmittance. Opposing radiation detectors then detect this transmitted radiation, thereby creating a pair of detection signals, By dividing the difference of the detection signals by the sum of the detection signals, a processor generates a beta angle error curve and finds the relative direction of the radiation. Based upon this beta angle error curve, the processor generates an appropriate error correction signal for guiding an object based upon the relative direction of the received radiation. The method and apparatus are readily applicable to guiding munitions using a laser monopulse to designate a target.

Abstract: A system and method that guides a device to an object using periodically adaptive guidance. The guidance and control system creates a reconstructed line-of-sight (LOS) vector to avoid system destabilization associated with small angle approximation during high bore sight engagements. The guidance system adaptively estimates the periodic maneuver of evasive objects with a set of harmonically balance Kalman filter banks. The Harmonically Balanced Kalman filter banks generate a set of probabilities that weight the effect of each individual Kalman filters on a resultant guidance command signal. The guidance command signal generated by the system acts perpendicular to the object LOS. The guidance and control system uses vectored proportional navigation guidance laws, optimal proportion navigation laws and periodically adaptive augmented guidance laws to generate a guidance command signal to supply to an autopilot.

Abstract: A target designation system for indicating a target to be destroyed by remotely guided ordnance comprising a receiver arranged to produce a receiver output signal in response to an incident electromagnetic signal from an attack aircraft. An auto-switch is connected to the receiver and arranged to produce a power signal in response to the receiver output signal. A transmitter is connected to the auto-switch to be activated by the power signal. When activated, the transmitter transmits a homing signal that indicates its location or the location of the target.

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: A system and method of providing situational awareness and weapon targeting is presented. The method includes determining the location of one or more enemy sites and one or more friendly sites. A “Do Not Engage” (DNE) zone is determined around each of the friendly sites and an “Allowable Engagement” (AE) zone is established around each of the enemy sites, wherein none of the AE zones overlap any of the DNE zones. An engagement plan is then determined based on the AE zones and integrity bounds on candidate munitions. The system includes a processing and communications network and a sensor element in communication with the processing and communications network. The system also includes a command control element in communication with the processing and communications network and an operating elements section in communication with the processing and communications network.

Abstract: A fuzing system for non-spinning or substantially non-spinning weapons is implemented by means of wide angle optics providing at least forward-hemisphere coverage, an array of infrared detectors and a microprocessor for image and data processing, aim-point selection, directional-warhead aiming and skewed-cone fuzing. The skewed-cone fuzing has a generatrix which is the vector sum of missile velocity, warhead velocity and the negative of target velocity.

Abstract: A guidance method for guidance systems is disclosed. The method includes forming a target track point with a target tracker. The method corrects the track point with a manual correction signal. A speed of rotation of the line of sight is determined with the target tracker. A track control system dynamic model is provided for forming an estimated value for the rotation speed of the line of sight. The estimated value for the rotation speed of the line of sight is formed from the determined speed of rotation of a line of sight corrected with a correction value generated with the dynamic model of the track control circuit based on the manual correction signal. The estimated value of the speed of rotation of the line of sight is then used for guidance.

Abstract: Applicants' Passive Radar Detector for Dualizing Missile Seeker Capability incorporates passive RF detectors into a standard active MMW seeker missile with a minimum requirement for hardware modifications. Anti-radiation homing (ARH) antennas and down conversion elements are added to the missile and coupled to existing signal-processing hardware. The added antennas intercept the air defense radar emission signals and the conversion elements convert the intercepted signals to the intermediate frequency (IF) usable by the MMW radar. The IF can then be processed by signal processor that already exists as a part of the MMW seeker.

Abstract: A method for operating a short range, air-to-air missile carried by an aircraft flown by a pilot. The missile includes a seeker operative to track a target. The method comprises providing a first indication to the pilot when the seeker is tracking a target, providing a second indication to the pilot when a rate of angular motion of the seeker falls below a given value for a predefined period.

Abstract: A target designation system for indicating a target to be destroyed by remotely guided ordnance comprising a receiver arranged to produce a receiver output signal in response to an incident electromagnetic signal from an attack aircraft. An auto-switch is connected to the receiver and arranged to produce a power signal in response to the receiver output signal. A transmitter is connected to the auto-switch to be activated by the power signal. When activated, the transmitter transmits a homing signal that indicates its location or the location of the target.

Abstract: An airborne missile launch system. The system includes a Harpoon aircraft command-launch control set (HACLCS) system, one or more Harpoon Block II missiles, and an interface controller coupled to the HACLCS system and the one or more Harpoon Block II missiles. The controller allows a user to create a missile profile mission. The controller combines the created missile profile mission with received positioning information. The missile(s) loads the combination into a navigation system of one of the Harpoon Block II missiles. The controller receives a mission-loaded signal upon completion of mission loading into one of the Harpoon Block II missiles, and converts the mission-loaded signal for interpretation by the HACLCS system.

Abstract: An electronic circuit for use in an anti-radiation missile system of the type which uses the electromagnetic transmissions of a target radar for guidance information, detects when the missile has flown into a target null and is no longer receiving energy from one of the main lobes or side lobes of the target radar transmitter. When this condition is detected, the circuit causes an attenuation in the epsilon error guidance signal to momentarily prevent guidance commands based upon the now suspect epsilon error signals from being implemented.

Abstract: A transmitted signal and a received signal are combined and the combination is expected to determine whether or not a target signal is present. Either the transmitted signal or the received signal is combined with an auxiliary signal containing a range of frequencies corresponding to an anticipated Doppler shift, so that an output of the combined transmitted and received signal will be present only if a target signal exhibiting a Doppler shift within the anticipated range is present. The auxiliary signal preferably comprises finite-duration signal portions of different types so as to provide a substantially uniform frequency response throughout the selected range.

Abstract: A target designation system for indicating a target to be destroyed by remotely guided ordnance comprising a receiver arranged to produce a receiver output signal in response to an incident electromagnetic signal from an attack aircraft. An auto-switch is connected to the receiver and arranged to produce a power signal in response to the receiver output signal. A transmitter is connected to the auto-switch to be activated by the power signal. When activated, the transmitter transmits a homing signal that indicates its location or the location of the target.

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: The present invention is directed towards a ballistic missile detection and defense system. The system of the present invention comprises a ship based interceptor or antiballistic missile, a missile launch detection system, a missile tracking system, and a ship based signal processing system capable of receiving said tracking signal calculating an intercept trajectory for an antiballistic missile to intercept a ballistic missile, and further capable of outputting an intercept trajectory program to an antiballistic missile.

Abstract: A method of maneuvering target tracing is disclosed. The present invention relates to the field of target tracking and more generally to a method of employing multiple model and variable sampling rate technique, which achieve good tracking performance for a high-g maneuvering target. The results show that the present invention can handle the missile sudden maneuver better and are accurate.

Abstract: The present invention concerns a method and an arrangement for determining the angle of roll of a launchable body (4) which rotates in its path. The launchable body (4) can consist of a rotating projectile, shell, guided missile or the like, launchable from a launching device (1). According to the invention the transmitter antenna (3) and receiver antenna (5) are each designed with their sweeping beams (6, 9) directed essentially towards each other. By detecting the time the two beams (6, 9) coincide and the signal strength received in the receiver antenna, the angle of roll of the launchable body can be determined.

Abstract: An autonomous onboard absolute position and orientation referencing system provides a means of efficaciously and economically embedding guidance and control components into the fins of supersonic, highly maneuverable small, medium-caliber and long range munitions. Embedded resonant cavities form an integral part of the referencing system. The magnitude and phase information received by the integral antennas is used to determine the munition orientation. Embedded sensors provide continuous, onboard information about the angular orientation of the munition, such as its pitch, yaw, and roll angles, as well as its absolute position relative to a ground station.

Abstract: A system for the detection and determination of the success of interception of incoming missiles, used in conjunction with a defense weapon system capable of identifying and tracking incoming missiles and interceptors. The system comprises at least one of a plurality of sensing units. Each sensing unit comprises: an optical sensor for detecting optical signals within a predetermined range; tracking means coupled to the optical sensor for tracking an intercepting missile or an incoming missile; processing means for processing optical input detected by the optical sensor and analyzing the optical input to identify an optical signature and determine detonation of interceptor or incoming missile; communicating means for communicating data between the sensing unit and the defense weapon system; and control means for controlling the tracking means, the processing means and the communicating data.

Abstract: A system for the detection and determination of the success of interception of incoming missiles, used in conjunction with a defense weapon system capable of identifying and tracking incoming missiles and interceptors. The system comprises at least one of a plurality of sensing units. Each sensing unit comprises: an optical sensor for detecting optical signals within a predetermined range; tracking means coupled to the optical sensor for tracking an intercepting missile or an incoming missile; processing means for processing optical input detected by the optical sensor and analyzing the optical input to identify an optical signature and determine detonation of interceptor or incoming missile; communicating means for communicating data between the sensing unit and the defense weapon system; and control means for controlling the tracking means, the processing means and the communicating data.

Abstract: The present invention includes a system and method for accurately locating moving targets. The system includes a targeting aircraft that has a radar system with a simultaneous SAR radar/moving target mode that generates an image and identifies moving targets in the generated image. The targeting aircraft also includes a mapping component that matches the generated image to a stored digital map, and generates moving target location information based on the matched image and map and the identified moving targets.

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: The present invention, in its various aspects and embodiments, includes a method for planning a mission profile in real time. The method comprises ascertaining a plurality of target information (including a target location, a target velocity, and a target location error) and autonomously determining a pattern from the ascertained target information.

Abstract: A missile defense system includes a tracking station for monitoring the course and/or trajectory of an incoming missile. The incoming missile course and/or trajectory information is communicated to an intercept missile, whose course and/or trajectory are calculated based on the information of the incoming missile received from the tracking system and the intercept missile location received from, for example, a GPS system. The tracking system monitors the flight of the incoming missile to determine any changes to its course and/or trajectory, and communicates these changes to the intercept missile. The intercept missile adjusts its course and/or trajectory based on the updated information received from the tracking station to provide accurate and reliable intercept of the incoming missile.

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 target designation system for indicating a target to be destroyed by remotely guided ordnance comprises a receiver arranged to produce a receiver output signal in response to an incident electromagnetic signal from an attack aircraft. A switch is connected to the receiver and arranged to produce a power ON/OFF signal in response to the receiver output signal. A transmitter is connected to the auto-switch to be selectively activated and deactivated by the power ON/OFF signal. When activated, the transmitter transmits a homing signal that indicates its location or the location of the target being illuminated by the transmitter signal.

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 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: A system and method for detecting a target. The inventive method includes the steps of receiving a complex return signal of an electromagnetic pulse having a real and an imaginary component; extracting from the imaginary component information representative of the phase component of the return signal; and utilizing the phase component to detect the target. Specifically, the phase components are those found from the complex range-Doppler map. More specific embodiments further include the steps of determining a power spectral density of the phase component of the return signal; performing a cross-correlation of power spectral density of the phase component of the return signal between different antenna-subarray (quadrant channels); and averaging the cross-correlated power spectral density of the low frequency components. In an alternative embodiment, the cross-correlation is performed on the phase component of the range-Doppler map directly.

Abstract: A radar receiver is shown wherein the frequency of a first local oscillator is changed to bring an intermediate frequency signal representative of a moving target into frequency coincidence with a signal from a reference oscillator of fixed frequency.

Abstract: The present invention includes a system and method for accurately locating moving targets. The system includes a targeting aircraft that has a radar system with a simultaneous SAR radar/moving target mode that generates an image and identifies moving targets in the generated image. The targeting aircraft also includes a mapping component that matches the generated image to a stored digital map, and generates moving target location information based on the matched image and map and the identified moving targets.