Abstract: A synchronous counter, the inventive counter is synchronized to a clock, e.g., a master clock of an FPGA, and includes a first counter that increments in response to the master clock, a resynchronizer that receives counter bits from the first counter and, when appropriate, generates an increment signal, and a second counter, clocked by the master clock, that increments in response to the increment signal. In a preferred embodiment, the resynchronizer is an n bit AND gate (where the first counter is an n-bit counter) that ANDs at least selected ones of the counter bits and a latch, e.g., a flip-flop, that latches the output of the AND gate. Thus, small counter chains are linked together using flip-flops clocked at the master clock rate, i.e., the same rate as the counter chains, to form a counter chain of any length that will function at the master clock rate.

Abstract: A colorless dopant is provided that has a viscosities approximately the same as that of liquid crystal compositions and supports low voltage operation. The dopants have one of three structures: (1) biphenyl; (2) diphenyl-diacetylene; and (3) double tolane, and in each case, have an amino group (secondary or tertiary) attached at one end of the molecule, with at least one polar group at the other end of the molecule. Schematically, the generic structure may be illustrated as: where R1 is an alkyl having from 1 to 12 carbon atoms, R2 is hydrogen or, independently of R1, an alkyl having from 1 to 12 carbon atoms, M is a polar group, X and Y are independently hydrogen or a polar group not necessarily the same as M, and (A) is (1) a single bond (biphenyl); (2) —C≡C—C≡C— (diphenyl-diacetylene); or (3) (double tolane), where Z is hydrogen, F, or alkyl.

Abstract: A system and method for processing the output of a fiber-optic gyroscope. The inventive circuit (10) includes a photodetector (24) for detecting electromagnetic energy received from the fiber-optic gyroscope (18,20) and providing an analog input signal in response thereto. An analog-to-digital converter (42) is provided for processing the analog input signal and providing a digital signal in response thereto. A source (30) is provided for injecting a dither signal between the photodetector (24) and the analog-to-digital converter (42). In the illustrative embodiment, the source (30) supplies a triangle wave signal. The output of the photodetector (24) is supplied to the summing input of a differential amplifier (29) and the output of the source (30) supplies the differencing input to the differential amplifier (29). The output of the analog-to-digital converter (42) is provided to a digital signal processor (44) as per usual practice.

Abstract: A system (16) for tracking a missile (22) in flight, the missile (22) having an optical beacon generator (32) that outputs a modulated signal (26) having a predetermined frequency, including an optical system (50, 52, 54) for transmitting image data along an optical path (68) onto an array of detectors (55), such that each detector in the array (55) receives substantially simultaneously the image data from the optical system (50, 52, 54). The system (16) further includes means for processing (46) the image data transmitted onto the array of detectors (55) in order to locate the optical beacon (32).

Abstract: A passive Q switch. The inventive Q switch includes a first wedge of material adapted to absorb electromagnetic energy. The first wedge has a first thickness on a first end thereof and a second thickness on a second end thereof diametrically opposite the first end. The first wedge has a first surface connecting the first and second ends and a second surface connected the first and second ends. The second surface is slanted relative to the first surface. A second wedge of material is included in the inventive passive Q switch. As per the first wedge, the second wedge has a first thickness on a first end thereof and a second thickness on a second end thereof diametrically opposite the first end. The second wedge has a first surface connecting the first and second ends and a second surface connecting the first and second ends. The second surface is slanted relative to the first surface.

Abstract: A system (30) for adjusting the orientation of a spacecraft adapted for use with a satellite (10). The system (30) includes a first control circuit (32, 38, 40) for canceling any momentum of the spacecraft via a counter-rotating spacecraft bus (16, 18). A second controller (32, 42, 44, 46, 48) orients the spacecraft via the application of internal spacecraft forces. In a specific embodiment, the spacecraft bus (16, 18) serves a dual use as storage section and includes a mass (16) having a moment of inertia on the same order as the moment of inertia of the satellite (10). The satellite (10) includes a bus section (16) and a payload section (14). The mass (16) includes the bus section (16). The first control circuit (32, 38, 40) runs software to selectively spin the mass (16) to cancel the momentum of the satellite (10). The software computes an actuator control signal, via a computer (32), that drives a first actuator (38) that spins the mass (16).

Abstract: An optical system includes a nonspherical outer dome that is rotationally symmetric about a central axis, a detector system, and an optical corrector positioned in an optical path between the outer dome and the detector system. At least one light baffle is positioned in the optical path between the outer dome and the detector system and is fixed in space relative to the central axis. There are typically from one to three baffles, each affixed to either the inter surface of the outer dome or to the optical corrector. Each baffle is a frustoconical tube that is rotationally symmetric about the central axis. A set of fins may be supported on one of the baffles, with each fin extending radially outwardly from an outer surface of the baffle and parallel to the central axis. The baffles combine to reduce stray light that otherwise would enter the optical system.

Abstract: A display device for a display wavelength range includes an image source, a relay group made of optical elements transparent to the display wavelength range, and a reflective combiner in facing relation to the relay group. The relay group includes a glass optical wedge, a glass lens, and a group of plastic lenses including a diffractive optical element. The group of plastic lenses is positioned between the glass optical wedge and the glass lens. The relay group has the optical wedge having a front face in facing relation to the image source, and a back face; an aspheric lens module having a front face in facing relation to the back face of the optical wedge, and a back face; and an aspheric lens having a front face in facing relation to the back face of the aspheric lens module, a back face, and an optical axis. The aspheric lens module is tilted and decentered with respect to the optical axis of the aspheric lens.

Abstract: A method for exploding a high explosive material confined in a casing which includes the steps of generating a laser beam; directing the laser beam toward a location on a surface of the casing; and irradiating the surface location with the laser beam a sufficient length of time to explode the high explosive material.

Abstract: A shaping optic for diode light sheets. The Fresnel cylinder lens has a plurality of facets that channel multiple light sheet output from a diode stack having arbitrary pitch and diode bar number into a gaussian pump light deposition profile within a laser gain medium. In a specific embodiment, the lens is formed of fused silica or BK7 glass covered with broad angle anti-reflection coating, and the vertical extent of the facets is matched to the pitch spacing of the diode.

Abstract: A technique is described for providing a pulsed radar exciter signal, in a radar exciter including a direct digital synthesizer (DDS). The DDS is reset pulse-to-pulse to provide a pulsed DDS signal having pulse-to-pulse phase discontinuities due to the resetting of the DDS. The phase of the pulsed DDS signal can be shifted pulse-to-pulse by a phase shift that is held constant over a pulse to correct the pulse-to-pulse phasing of the DDS signal. A discrete phase modulator can provide the phase shift. The phase of the pulsed DDS signal can be shifted pulse-to-pulse by an additional phase shift which is a linear phase sequence from pulse-to-pulse, or by an additional phase shift which is a quadratic phase sequence from pulse-to-pulse to produce a ranging waveform.

Abstract: The far field pattern of a slotted planar array antenna is predicted at extreme angles using an improved prediction method. The prediction method acquires planar near field data for a slotted planar array antenna and then back-transforms the planar near field data to the aperture of the antenna corresponding to X position, Y position, amplitude and phase data for the array antenna. An interpolation process calculates the excitation coefficient (phase and amplitude) of each slot element of the antenna using the back-transformed data. The excitation coefficients are then processed using an array factor program to predict the far field pattern of the antenna.

Abstract: An antenna array system with dynamic signal routing to a set of receivers. A monopulse electronically scanned antenna (ESA) has a plurality of antenna elements divided into subarrays. ESA beam steering phase shifters are associated with the respective subarrays of antenna elements, such that the output signals from the respective antenna elements associated with the respective quadrants are phase shifted and summed to provide respective subarray signals. A monopulse network responsive to the subarray signals provides monopulse outputs to a set of receivers. A beam steering controller provides phase shift commands to the ESA phase shifters to set the phase shift associated with the respective phase shifters of the subarrays. The controller commands the ESA phase shifters to modulate the phase shift of selected quadrants.

Abstract: A gun trunnion angular-sensing mechanism (30) is operable with a gun (20) mounted for elevational rotation on a gun trunnion (22). The angular-sensing mechanism (30) includes an angular-position readout device (32) having an input shaft (34), and a pinned parallelogram linkage (46) extending between the gun trunnion (22) and the input shaft (34) of the angular-position readout device (32). The linkage (46) rotates the input shaft (34) proportionately to a rotation of the gun trunnion (22), so that the angular position of the gun trunnion (22) may be sensed.

Abstract: A scanning sensor system includes a light sensor and a scanning telescope having a first telescope subassembly and a second telescope subassembly. Each of the telescope subassemblies has a primary telescope mirror oriented to receive an incident light beam over an angular viewing range as the primary telescope mirror is rotated about a primary-mirror rotation axis, and at least one additional telescope mirror positioned to receive a reflected light beam from the primary telescope mirror. A primary mirror drive rotates the primary telescope mirrors about the primary-mirror rotation axis at a primary mirror angular instantaneous rate of rotation. A half-angle derotation mirror has a derotation-mirror axis parallel to the primary-mirror rotation axis. The half-angle derotation mirror is positioned to reflect light in the optical path when each primary telescope mirror is within the angular viewing range and to direct the reflected image along the optical path toward the sensor.

Abstract: A fin lock device (12) for a missile. The device (12) provides a mechanism for locking a missile fin (14) by grasping an edge of the fin (14) and a mechanism (32, 42) for retracting the locking mechanism (18) to release the fin (14). The fin (14) is grasped by a notch (20) therein adapted to receive the edge of the fin (14). The piston (18) is retracted by burning a pyrotechnic powder in a cavity adjacent to the piston (18) to fill the cavity with gas and create a pressure differential to force the piston (18) away from the fin.

Abstract: An impulse radar guidance system and method for use with a spinning projectile. The system and method tracks the flight of the spinning projectile using an all-weather radar or tracker. A linearly polarized asymmetric waveform is transmitted at the projectile that comprises a series of repeating pulses having a relatively strong, short, positive electric field pulse followed by a relatively weak, long, negative electric-field baseline. The projectile contains a dipole antenna having a switching diode disposed between respective halves thereof.

Abstract: A missile system includes a launcher having a built-in pulse power source and an electrical connection to a missile. The pulse power source is used to send activation and firing pulses to the missile. The pulse power source utilizes a piezoelectric crystal which produces a pulse of energy when struck by a spring-loaded hammer that is released by an operator. In one version, a first piezoelectric crystal produces a first pulse to activate the system when struck by a first hammer, and a second piezoelectric crystal produces a second pulse to fire the missile when struck by a second hammer. The energy pulses are conducted from the launcher to the missile through an inductive coupling between a primary induction coil in the launcher and a facing secondary induction coil in the missile.

Abstract: A method and apparatus for protecting a bolometer antenna imaging array from out of band electromagnetic energy is disclosed. Protective pads are disposed upon a window in an optical system forming a millimeter wave image on an array of bolometer antenna sensors. The protective pads are effectively opaque to infrared and visible emissions and are aligned to shade the bolometer portion of the bolometer antennas from infrared and visible emissions, while leaving the antenna portion of each sensor in the array exposed to intercept the millimeter wave energy incident upon them.

Abstract: A silicon-based radiation-hard cryo-CMOS CCD process suitable for fabrication of devices (100) with sub-micron feature sizes. A re-oxidized nitride/oxide (RONO) layer (49″) is preserved in the CCD area (32) while plasma etching is used to define polysilicon 1 gates (50′) in the active FET area of the device. Thereafter, a wet chemical etching process, which does not destroy the integrity of the RONO layer (49″) in the CCD area, is carried out. A channel stop (48) is formed after the field oxidation step in the active FET area to reduce the space required for minimum diode breakdown voltage between the n+ source/drain region and the p+ channel stop.