Abstract: Switching apparatus for switching on and off one or more microwave tubes. A preferred embodiment of the switching apparatus comprises a solid state magnetron switcher that switches a plurality of magnetrons on and off using a plurality of high voltage (IGBT) switches. The microwave tubes or magnetrons are driven from a single power supply. The technical approach employed in the present invention places all microwave tubes or magnetrons into low level oscillation prior to switching them into full conduction. This maintains minimal voltage across the high voltage switches while allowing only a small percentage (1-2%) of full load current to be drawn.

Abstract: A hybrid two-stage cryocooler includes a first-stage Stirling expander having a first-stage interface and a Stirling expander outlet, a thermal-energy storage device in thermal communication with first-stage interface, and a second-stage pulse tube expander with a pulse tube inlet. A gas flow path extends between the Stirling expander outlet and the pulse tube inlet, and a heat exchanger is in thermal contact with the gas flow path. The relative cooling power of the first and second stages may be controlled to increase the cooling power of the second stage relative to the first stage in response to an increased heat load to the second stage. The thermal-energy storage device acts as a thermal buffer during this period, and is later cooled when the relative cooling power is adjusted to increase the cooling power of the first stage.

Abstract: A face-cooling scheme is used with multiple nonlinear crystal formats used primarily for second harmonic generation without the need for air-path rephasing between the crystals. Birefringent crystals, e.g., MgF2, are cut and oriented such that there is no dispersion between the fundamental and second harmonic wavelengths within each crystal. The crystals are then disposed in a heat-conducting housing sandwiched by two or more nonlinear crystals and used as the face-cooling medium, thereby causing the heat generated in the nonlinear crystals by absorption at the fundamental and second harmonic wavelengths to flow longitudinally (direction of beam propagation) into the face-cooling medium. This minimizes any transverse thermal gradient in the nonlinear crystals and the attendant dephasing loss. The crystals can be dry stacked with a very small gas-filled gap, immersed in a liquid or gel, bonded with optical cement, optically contacted, or diffusion-bonded together to form a composite crystal.

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 an noise error corrected output signal. In the preferred embodiment, the error signal is scaled prior to being multiplied by the second frame. A min-mean filter is provided to remove dome shading effects from the frames of image data. In the best mode, the min-mean filter is disposed in the main path and blurred and focused outputs therefrom are weighted, averaged and stored.

Abstract: A post-correlation nulling circuit (10) derives from a narrowband jammer a replica of the baseband jammer noise which is used to adaptively cancel the jammer noise waveform in the receiver baseband after PN processing, thus allowing the adaptive antenna spatial nulling to concentrate on canceling wideband jammers.

Abstract: An explosive countermeasure device is designed to negate an electro-optical seeker system of a missile at least temporarily so that it loses lock on a target aircraft. The device has a central explosive charge with a detonator and a container surrounding the charge for holding a noble gas under pressure. When the charge is detonated, the resultant explosive shock wave will heat the gas to a temperature sufficient for it to emit a short, intense flash of light before the container disintegrates, blinding the electro-optical seeker system at least temporarily.

Abstract: Very compact, high numerical aperture, high resolution, ultra-wide field of view concentric optical apparatus. The concentric optical apparatus comprises a concentric lens and a focal surface array disposed along a focal surface of the concentric shell outer lens. The optical apparatus may further comprise an image intensifier tube optically coupled to the concentric lens by way of a curved fiber optic relay having an input surface that is concentrically disposed with respect to the concentric lens. The optical apparatus may also comprise a dewar that houses the focal surface array, and wherein the concentric lens comprises a cold stop for the focal surface array.

Abstract: A thermal birefringence compensator for a double pass laser system, which includes a polarization or conventionally outcoupled laser resonator, a gain medium and a compensator optically coupled to the gain medium. In one implementation, the compensator, which acts as an end reflector, includes a Benson prism, a first quarter waveplate with its principle axes aligned to the fold axis of the Benson prism, and a second quarter waveplate with its principle axes at 45° to the fold axis of the Benson prism. Alternatively, the compensation's prism can be a Porro prism.

Abstract: The present invention is directed to the synthesis, processing and test of improved spin-on precursor materials comprising at least one Group II metal and at least one Group IV or Group V metal, useful for making thin oxide films, useful, for example, in various electronic devices, such as ferroelectric devices. For example, barium strontium titanate spin-on precursor materials are useful for making thin films of barium strontium titanate (BST) for, e.g., ferroelectric capacitors. A method is provided for fabricating electronic devices employing such Group II-Group IV (or V) oxides as the active device, using polyether acids. The method comprises: (a) providing a substrate; (b) forming a bottom electrode on the substrate; (c) depositing a solution comprising polyether acid salts of the Group II and Group IV or Group V metal ions; (d) forming the oxide film from the solution; and (e) forming a top electrode on the oxide film.

Abstract: A beamforming system including a multiplier stage for providing a plurality of steered signal terms, each term being a product of an input signal term and a steering signal term. A filter multiplies the steered signal terms by a plurality of respective filter weights to provide a plurality of weighted products. The weighted products are summed to provide an output beam directionally responsive to the steering signal. A microprocessor provides the steering signal terms and the filter weights in response to the input signal and/or user input. In the preferred embodiment, the filter is a reconfigurable, general purpose matched filter configured to multiply a plurality of delayed representations of a respective one of the steered signal terms by a plurality of the weights to provide a plurality of intermediate weighted product terms. The filter further includes a summing circuit for accumulating the intermediate weighted product terms to provide a respective one of the plurality of weighted products.

Abstract: Metal acid salt complexes are provided comprising (1) a first metal ion consisting essentially of bismuth, and optionally, at least one second metal ion selected from the group consisting of barium, calcium, strontium, lead, titanium, tantalum, and niobium, and (2) a polyether acid. The metal acid salt complexes are prepared by combining (1) bismuth ion, and optionally, at least one second metal ion and (2) at least one of a polyether acid and a polyether acid anhydride prepared from the polyether acid. In particular, the use of a mixture of bismuth, strontium, and niobium and/or tantalum salts of the hydrophilic acid 3,6-dioxaheptanoic acid salt is described for production of ceramic thin films, such as for use in ferroelectric devices, using non-toxic solvents. As a consequence, improved electronic devices are formed from less toxic and easier handled precursors and solvents.

Abstract: A coordinate transformation apparatus (138) in an aircraft-based missile guidance and tracking system for adjusting aircraft and missile position signals for a roll angle about the line of sight in the guidance and tracking system sight unit (40) caused by roll of the aircraft subsequent to firing of the missile. The apparatus (138) incorporates analog to digital converter means (140), (144), (156), (160) and (180) to convert the analog aircraft and missile position signals to digital signals for input into a microprocessor (168). The microprocessor (168) computes the roll angle as well as a change in roll angle over time around the line of sight of the sight unit (40) and subsequently adjusts the digital signals to compensate for the computed roll angle and change in roll angle. Digital to analog converter means (182), (186) and (190) convert adjusted digital signals to analog signals and output the adjusted analog signals for computation of missile guidance signals by the system.

Abstract: Dual-cavity resonators that may be optimized for multiple functions (operating modes). The dual-cavity resonators provide a first set of operating modes that exhibits low repetition rates (5-20 Hz), high energy per pulse, and long, pulse-width, and a second set of operating modes that exhibits high repetition rates (100-2000 Hz), low energy per pulse, and short pulse-width.

Abstract: Methods including a Kalman filter tracking method for localizing a magnetic field source and which employs a linear perturbation method. The linear perturbation method linearizes an objective function in the neighborhood of the actual source enabling the source location to be computed in a single operation. Successive applications of the linear perturbation method lead to successive improvements in the localization result.

Abstract: An unproved optical bench for use in an optical system, such as a miniaturized laser transmitter, or the like. The optical bench has a housing with a plurality of V-shaped grooves formed therein. Optical elements of the optical system in which the optical bench is used are secured, such as by bonding, in the plurality of V-shaped grooves. The optical bench thus rigidly mounts the optical elements of the optical system to produce a compact and lightweight structure that is relatively insensitive to environmental extremes.

Abstract: A blur film is made of a polymeric film material transmissive to infrared energy of a selected waveband, which is affixed to a surface of a substrate transmissive to energy of the same selected infrared waveband. The blur film has a texture or a plurality of lenslets thereon, where the surface of each lenslet is a surface of revolution. In a spatial-filter wheel application, the blur film and substrate are affixed to a support, which in turn is rotatably mounted on a drive. The support is structured such that a portion of its circumference is covered by the blur film and a portion of its circumference is not covered by the blur film. The spatial-filter wheel is rotated in front of a detector to produce alternating blurred and direct images on the detector.

Abstract: An optical rotator includes a pair of waveplates which receive a polarized beam having a first state and outputs a polarized beam having a second state rotated 90° with respect to the first state. In the illustrative embodiment, the first and second waveplates are physically coupled to one another.

Abstract: A magnetic object tracking algorithm, that may be implemented as an apparatus or a method, that permits kinematic tracking of magnetized objects, or targets, using magnetic field strength measurements derived from one or more vector magnetometers. The magnetic object tracking algorithm effectively tracks a maneuvering magnetic dipole target using an extended Kalman filter directly observing (processing) real magnetic field strength data.

Abstract: A cleaning system and method utilizing sonic whistle and other agitation methods to enhance the soil removal and mass transport capacity of the liquid carbon dioxide at low process temperatures. Agitation devices disposed in or couple to a cleaning chamber, and cause the liquid carbon dioxide to ultrasonically emulsify and disperse non-miscible liquids or insoluble solids, such as remove low solubility oils and greases. Cleaning is accomplished at temperatures between −68° F. and 32° F., and the temperature of the liquid carbon dioxide is typically below 32° F.

Abstract: An improved tracking and guidance system is provided for line-of sight commanded missiles. The system includes a missile mounted laser beacon which is modulated at a predetermined frequency. An infrared sensor mounted on a tracking unit receives the incoming optical energy and provides a corresponding electrical output. The output signals are filtered to eliminate clutter and those signals outside the range of frequencies within which the laser is modulated. The filtered signals are then peak detected to determine missile azimuth and elevation within a predetermined window. Azimuth and elevation error detector circuits compare the missile azimuth and elevation to predetermined signals to generate error signals. The error signals are utilized by the missile guidance system to provide updated guidance commands.