Abstract: An accurate target detection system. The system includes a sensor (22) that receives electromagnetic signals and provides electrical signals in response thereto. A non-uniformity correction circuit (28, 38, 52) corrects non-uniformities in the sensor (22) based on the electrical signals and provides calibrated electrical signals in response thereto. A third circuit (30, 32, 34, 38, 42, 44, 52) determines if a target signal is present within the calibrated electrical signals and provides a target detection signal in response thereto. A fourth circuit (38, 40, 48) selectively activates or deactivates the non-uniformity correction circuit (28, 38, 52) based on the target detection signal. In a specific embodiment, the sensor (22) is an array of electromagnetic energy detectors (22), each detector providing an electrical detector output signal.

Abstract: A high power TM01 mode radio frequency antenna. The inventive antenna comprises a conical horn for receiving an electromagnetic input signal and radiating an output signal in response thereto. An inner window is disposed within the conical horn. An outer window is mounted at an output aperture of the conical horn in alignment with the inner window. The antenna has a gradual taper from a waveguide input to the aperture over a cone angle of 45 degrees. The outer window is mounted at the aperture in concentric alignment with the inner window. For an optimal compact design, the inner and outer windows are of polycarbonate construction.

Abstract: A system and method adapted for use with a focal plane array of electromagnetic energy detectors to receive first and second frames of image data from electromagnetic energy received from at least a portion of a scene. The first frame is a focused frame and the second frame is a blurred frame. In a feed-forward path the system compares the first frame to the second frame and provides an error signal in response thereto. In a main path, the system multiplies at least a portion of the second frame of image data with the error signal to provide a noise error corrected output signal. In the preferred embodiment, a wavelet filter is used to remove dome shading effects from the frames of image data. In the best mode, the wavelet filter is disposed in the main path and blurred and focused outputs therefrom are weighted, averaged and stored.

Abstract: A system (10) for determining the range between a missile (14) and a target (18) adapted for use with a semi-active missile system. The system (10) includes a first circuit (12) for generating a periodic signal (24) that is periodically frequency modulated. A second circuit (16) determines a closing rate at which the missile 14 is approaching the target 18 via the periodic signal 24. A third circuit (16) determines a value containing information corresponding to the range and the closing rate via the periodic signal. A fourth circuit (16) determines the range from the closing rate and the value. In a specific embodiment, the first circuit (12) includes an illumination system (12). The illumination system (12) includes a periodically modulated carrier signal generator (32) that generates the periodic signal (24). The periodically modulated carrier signal generator (32) includes a frequency source, a frequency modulator, and an illumination system computer.

Abstract: A programmable optical system that dynamically corrects or induces aberrations into the optical path of a missile seeker. The system is dynamic in that the amount and type of aberration may be changed while the missile is in flight. The dynamic correction is accomplished by means of deformations applied to a low-mass mirror or mirrors in the optical path of the missile seeker. The missile includes an aspheric dome, and the optical system is dynamically compensated for aberrations introduced by the dome as the seeker system is moved through the field of regard.

Abstract: A radiator (10) comprising one or more centered longitudinal shunt slots (12) disposed in a rectangular waveguide (11) that are fed by corresponding offset ridge resonant irises (14). The offset ridge resonant irises that are centered on each respective slot. When multiple slots and offset ridge resonant irises are employed, adjacent irises are oriented opposite to one another.

Abstract: A system using a scanning mirror for scanning the field of view of an optical objective. The scanning mirror is mounted for rotation about an axis transverse to the major plane of the mirror and for pivotal oscillation about an axis lying substantially within the major plane of the mirror. The combined effect of rotation and pivotal movement is to scan the field of view of an optical objective. The scanning angle and other significant characteristics of the scan pattern may be changed as desired by means external to the system, producing, for example, a rosette, spiral, or circular scanned pattern with or without dimensional changes in the total scanned field of view. Such a scanning system may be embodied in seeker systems used for the guidance of radiation-seeking missiles operating in single or multiple regions of the electromagnetic spectrum.

Abstract: A missile includes a fuselage with a roll axis and a nod axis perpendicular to the roll axis, and a conformal window mounted to a forward-facing end of the fuselage. There is a sensor system with a field of regard through the window and a line of sight, and a sensor system pointing mechanism affixed to the airframe and upon which the sensor system is supported. The sensor system pointing mechanism includes a gimbal structure having a first degree of rotational freedom about the roll axis and a second degree of rotational freedom about the nod axis, and a linear translational mechanism connected to the sensor system. The linear translational mechanism is operable to translate the sensor system away from the window with increasing angular deviation of the line of sight of the sensor system from the roll axis. Preferably, the translational mechanism is a slider-crank mechanism.

Abstract: An algorithmic technique which allows antenna arrays that are used for interferometric direction finding to have elements with arbitrary orientation. This technique allows the phase errors associated with non-identical element orientation to be estimated, without explicit knowledge of either the polarimetrics of the array elements or the polarimetrics of the source. It relies upon the fact that there exists a single number which describes the polarimetric interaction, and that this number can be estimated and then utilized to remove the phase component due to polarimetric interaction. This technique makes it feasible to incorporate direction finding arrays into articles that could benefit from such arrays, but because of size or shape constraints, were previously not able to do so.

Abstract: A missile guidance system with a fixed body missile seeker having an adjustable look angle. The missile seeker has a fixed camera whose look angle is adjustable to keep a moving target within the field of view of the camera. The target is tracked by a tracker to generate target angle and line of sight rate signals. The target angle signal is input to pointing angle adjustment apparatus which adjusts the look angle of the camera. The pointing angle adjustment apparatus may comprise a stepper motor that controls the angular position of a gimbal on which the camera is mounted. Alternatively, the pointing angle adjustment apparatus may comprise one or more stepper motors that control an adjustable zoom lens or a plurality of optical wedges, respectively. A body angular rate output signal of a body-fixed inertial measurement system is summed with the line of sight rate signals from the tracker to determine the inertial line of sight rate of the moving target.

Abstract: A compact high-performance antenna. The antenna includes a waveguide (16) for providing or receiving electromagnetic energy. A feed circuit (18, 106, 108, 110) provides or receives the electromagnetic energy to or from the waveguide (16). A radiating circuit (112, 114) provides or receives the electromagnetic energy to or from the feed circuit (18). One or more notches (120) in the feed circuit (108, 110) compensate for insertion phase errors in the electromagnetic energy. One or more tabs (18) in the radiating circuit (112, 114) compensate for radiation phase errors in the electromagnetic energy. In a specific embodiment, the antenna is a dipole antenna and includes an array of dipole cards. The radiating circuit (112, 114) includes first (112) and second (114) radiating circuits included in each of the dipole cards (14). The first (112) and second (114) radiating circuits include a plurality of quarter-wave stripline transformers (24).

Abstract: An optical system includes a window made of a curved piece of a transparent material having an inner surface and an outer surface. The inner surface has a nominal inner surface shape defined by a first conicoidal relationship, and the outer surface has a nominal general aspheric surface shape. The optical system also typically includes a sensor and an optical train on the side of the inner surface of the window. The accuracy of the shape of the inner surface is tested by directing a coherent light beam through a remote focus of the inner surface, reflecting the light beam from the inner surface toward an adjacent focus of the inner surface, reflecting the light beam from a spherical reflector at the adjacent focus of the inner surface and back toward the inner surface, reflecting the light beam from the inner surface back toward the remote focus, and interferometrically comparing the reflected beam arriving at the remote focus with a reference beam.

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: Disclosed is a common aperture dual polarization antenna array (30). This common aperture dual polarization antenna array (30) includes an antenna aperture (36) and a plurality of centered slot arrays (32) positioned within the antenna aperture (36). A plurality of notch dipole arrays (34) are positioned within the antenna aperture (36) and positioned substantially orthogonal to the plurality of centered slot arrays (32). A first feed guide (46) is coupled to the plurality of centered slot arrays (32) and a second feed guide (56) is coupled to the plurality of notch dipole arrays (34).

Abstract: A microwave source system includes a magnetron source having an antenna, and an output dome covering the antenna. The output dome is formed as a ceramic substrate having an inner surface and an outer surface, and a conductive layer of a high thermal conductivity material overlying and contacting the inner surface and/or the outer surface. The ceramic substrate is preferably fused quartz, and the conductive layer is preferably polycrystalline synthetic diamond.

Abstract: A Cassegrain antenna system includes a flat dielectric plate radome having a thickness of one-half wavelength at a frequency of operation. The plate has an electrically conductive grid disposed on an inside surface thereof to permit perpendicularly polarized energy rays to pass there-through. A parabolic twist reflector is spaced from the radome, and includes a dielectric substrate having a thickness equivalent to one-quarter wavelength at a frequency of operation and having formed on an interior surface thereof an array of conductive strips oriented by 45 degrees relative to the incident ray polarization. A conductive ground layer is formed on an exterior surface of the substrate, wherein radiation reflected by the ground layer and passing through the dielectric substrate is shifted by 180 degrees in phase and is rotated in polarization when combined with energy reflected from the conductive strip array by 90 degrees relative to radiation incident on the twist reflector.

Abstract: A self destruct mechanism for an airborne projectile is provided. The projectile includes a navigation system which provides an absolute global position of the projectile. The position is compared with positions stored in memory. If the position of the projectile is determined to be acceptable, operation of the projectile continues. If the position of the projectile is unacceptable, an electronic control system initiates a self-destruct signal for the projectile.

Abstract: An optically-aided, inertially guided missile. The inventive missile includes a receiver for accepting guidance commands from a source located on an independent frame of reference relative to the missile and providing a first signal in response thereto. A filter is mounted on the missile for processing the first signal and providing a second signal in response thereto. The filter outputs commands to a navigation system which provides missile guidance commands in a conventional manner. In the illustrative implementation, the filter is a Kalman filter configured to eliminate the effects of gunner jitter and optical guidance system noise thereby significantly improving missile terminal performance at long ranges. In the illustrative implementation, the navigation system includes an inertial sensor assembly. The navigation system outputs a signal representative of missile-to-target cross track position and velocity in response to outputs from the sensor assembly and the filter.

Abstract: A neural network controller for a pulsed rocket motor tactical missile. The missile includes a fuselage or body, with a propulsion system. The pulsed propulsion system has a need for a logical control of the application of propulsion energy throughout the missile's flight. The controller is trained to provide optimal initiation of individual rocket motor thrust pulses based on tactical information available at various points/times in the missile's flight. The controller training is through use of training cases, in which the network learns to output a specific target value(s) when specific values are input. When trained with a large sample of training cases selected from the multidimensional population of interest, the neural network effectively learns the correlations between inputs and outputs and can predict input/output relationships not previously seen in any training case.

Abstract: A high-power wideband transformer (40). The transformer (40) includes a first input terminal (42) connected in parallel to one or more conductor paths (50 and 52) and to a first output conductor (48). A second input terminal (44) is connected in parallel to the one or more conductor paths (50 and 52) and to a second output conductor (54). An inductive device (56, 60, 64, 58, 62, and 66) effects electrical coupling between the one or more conductor paths (50 and 52) and the first output conductor (48) and between the one or more conductor paths (50 and 52) and the second output conductor (54) sufficient to implement a desired transformer ratio from input of the transformer (40) to output of the transformer (40) via approximately colinear wires (56, 60, and 64). In a first illustrative embodiment, the co-linear wires (56, 60, and 64) are parallel wires placed sufficiently close to effect the electrical coupling. The transformer 40 effects a nine-to-one transformer ratio.