Abstract: Bistatic radar compatible for investigating the employment of a high-altitude UAV working in tandem with a group of low-altitude UAVs. The bistatic radar is divided into a position-adaptive bistatic mode and a close-range monostatic mode. In position-adaptive (robotic) bistatic mode, each low-altitude UAV estimates a new parameter denoted as the differential path length to adaptively implement self-adjustments in position. This approach provides each UAV with the potential for looking down the “throat” of an obscuration channel. In the event that a particular low-altitude UAV detects an obscuration channel, the low-altitude UAV will transfer to a close-range monostatic mode in an effort to interrogate the obscuration channel for targets.

Abstract: A hand-held dual frequency satellite communication antenna of circular polarization-capable characteristics is disclosed. The antenna system is based on Yagi/Udi spaced elements, including tuned trap-enabled dual frequency elements, disposed in orthogonal planes of a hand-receivable antenna boom element. The antenna system is fabricated from low cost readily obtainable materials and in a manner permitting easy disassembly and packaging for carriage to an isolated location of usage. Configuration of the disclosed antenna system for transmission and reception in two different popular amateur radio satellite communication bands is included. Antenna system field pattern characteristics and actual element lengths are included in the disclosure.

Abstract: A moving platform to moving target relative locating apparatus using long baseline interferometer algorithm measurements and signal time difference of arrival data to operate the algorithm. Signal delays measuring in a few picoseconds are used in plural interferometer algorithms to determine straight-line vector paths between moving platform and moving target. Self-calibration of the picosecond time difference of arrival signal paths is provided. Use of the invention to passively locate a moving target in azimuth elevation and range from a moving aircraft using either aircraft-mounted or aircraft-tethered radio frequency signal antennas and a single pulse of received data is also included.

Abstract: A method and device for visually detecting crack length of a temperature sensitive paint coated test structure during excitation of the test structure. The method and device of the invention capitalizes on surface temperature changes of the test structure as structural fatigue increases. Test structure surface temperature changes are realized in corresponding fluorescence intensity changes in the temperature sensitive paint and recorded with a CCD camera. Improvements over conventional structural fatigue systems include the ability to detect fatigue during flight testing, to record fatigue without stopping the electrodynamic excitation and the ability to detect crack onset and crack length resulting in more accurate cycles-to-fatigue analysis.

Abstract: A micromechanical electrical systems (MEMS) metallic micromachined multiple ported electrical switch receivable on the die of an integrated circuit and within the integrated circuit package for controlling radio frequency signal paths among a plurality of switch-enabled different path choices. The switch provides desirably small signal losses in both the switch open and switch closed conditions. The switch is primarily of the single pole multiple throw mechanical type with possible use as a single input pole, multiple output poles device and provision for grounding open nodes in the interest of limiting capacitance coupling across the switch in its open condition. Cantilever beam switch element suspension is included along with normally open and normally closed switch embodiments, electrostatic switch actuation and signal coupling through the closed switch by way of increased inter electrode capacitance coupling. Switch operation from direct current to a frequency above ten gigahertz is accommodated.

Abstract: An improved global positioning system satellite signal acquisition method and device. The method and device of the invention reduces the number of operations in the block correlation used in determining Doppler frequency and time of the received GPS C/A and P(Y) codes. Reducing the number of operations in block correlation increases acquisition speed and reduces energy requirements, aspects conducive to commercial and military hand held GPS receivers.

Abstract: A subterranean course-defining laser instrument and a system for initial calibration or setup of this instrument to provide accurate definition of a sub surface course for a pipeline or the like. Instrument setup is made in response to an above-ground course definition marker such as a surveyor's stake or surveyor's rod. A double mirror pseudo periscope arrangement is used to enable optical signal communication from the subterranean location of the laser instrument to the above ground marker with each of the mirrors being of a curved and error-minimizing nature. Details regarding two major components of the apparatus and quantitative consideration of achieved error budget are included.

Abstract: A cavity ring-down spectroscopy device and method suitable for materials with low and high absorption coefficients. An optical signal introduced into an optical cavity resonates through a length of fiber amplifier coupled to the optical cavity. The optical signal resonates through a fiber amplifier active section resulting in a gain compensating for optical losses. The gain obtained by use of the fiber amplifier is then modulated between two predetermined levels. By virtue of employing an optical fiber, the cavity ring down spectroscopy device and method is insensitive to misalignment and therefore iminently capable of portability.

Abstract: A dynamic programming network integrating sensor management, sensor fusion, and an application in a seamless structure in which these functions are mutually dependent and develop autonomously and concomitantly with experience. The dynamic programming network autonomously divides these functions into multiple subtasks that it can assign to the processors of a fine-grained parallel computer. As the number of processors available for these subtasks increases the network may attain its objective more efficiently. This architecture confers the greatest advantage in feature-rich applications such as identification of targets in synthetic aperture radar, visual, and infrared images. The design can be extended, however, to such diverse and general applications as control problems and machine intelligence.

Abstract: A solid state laser device made from a nonlinear optic quaternary alloy of Silver, Gallium, Selenium and Tellurium semiconductor material or Silver, Gallium, Sulfur and Tellurium semiconductor material. The Tellurium component in each alloy provides quaternary alloying anion modification of an underlying ternary semiconductor crystal and achieves tuning of the birefringence and tuning of the wavelength passband of the semiconductor material. The tuned quaternary alloy enables beam walkoff-free noncritical phase match operation of the laser device including use of a phase match angle supporting optimum use of the material's nonlinear properties, maximized useful length of the material crystal, room temperature wavelength changing operation, significantly increased second order nonlinear susceptibility, a factor of ten reduction in the walk-off angle and photon energy conversion efficiencies several times those usually achieved.

Abstract: Formation of for example yttria stabilized zirconia films of significant 001 orientation on a variety of substrates including amorphous material and room temperature limited material is disclosed. The yttria stabilized zirconia film formation is achieved using pulsed laser ablation of a polycrystalline yttria stabilized zirconia target source while the substrate is electrically biased, disposed at a selected angle and maintained at substantially room temperature in the presence of an argon atmosphere. The film formation uses low bias voltage, requires no ion beam apparatus and employs low temperatures sufficient only to enable process stabilization. Film formation is accomplished in a step sequence wherein each step responds to temporal and spatial component segregations occurring in a laser-ablated ion plume.

Abstract: A weaker signal receiving system inclusive of stronger nearby-sourced interference signal cancellation capability. Stronger interference signal cancellation is accomplished by actively canceling or subtracting from the received signal an intermediate signal in which the weaker signal has been attenuated but the stronger signal remains. Attenuation of the weaker signal in this intermediate signal is accomplished in a feedback loop arrangement by an amplitude-responsive signal processing element embodied from for example a ferrite material such as yttrium iron garnet disposed in a physical wave propagating and wave amplitude sensitive film. The cancellation or subtracting is accomplished using received signals and without need for a direct output sample of the stronger signal at its source. Military aircraft use of the disclosed system in the microwave and other spectral regions with transmission mode as opposed to reflection mode signal amplitude discrimination by the ferrite device is included.

Abstract: A system for communicating hardened, buried target arrival-related data from an airborne warhead device to a remote mission analysis location is disclosed. The communicated information especially relates to impact deceleration events encountered by a hardened target penetration warhead, events arising from the warhead impacting with the earth and then with one or more layers of hardening material such as concrete disposed in or adjacent a subterranean target. Verification of warhead detonation may also be included in the communicated data. The system includes ultra high radio frequency communication from the subterranean warhead to a repeater apparatus disposed at or above the point of warhead earth impact followed by conventional signal relaying of the collected warhead experience data from the repeater to a remote mission analysis facility.

Abstract: A switch modulated low duty cycle low energy mass limited radio frequency beacon system for locating spent, un-exploded or experimental munitions projectiles in a large open-air test range or within a dirt backstop. The disclosed locator beacon is mounted on a rear portion of a projectile before launch and includes a protective (and antenna length-shortening) resin dielectric material housing in which locator beacon circuit components are contained and immunized against high G forces by a combination of component supporting, energy deflecting and energy absorbing protective arrangements.

Abstract: An electronic warfare radio receiver of the monobit type wherein the signal processing circuitry, including a bandpass filter array, analog to digital converter circuit and Fourier transformation circuit, are located in a plurality of parallel-disposed but isolated receiver channels. The parallel disposed receiver channels limit interference between received signals and enable the customary processing of two simultaneous input signals of differing signal strength in each receiver channel; this increases the number of simultaneous input signals processable by a factor equaling the number of receiver channels used. Single chip embodiment of the receiver is disclosed thereby tending to compensate for the added complexity of the channelized processing. Signals falling in digital filter overlap regions are addressed by the invention.

Abstract: A laser energy window arrangement especially usable in a tactical aircraft having night vision equipment-aided cockpit visual information input requirements. The laser energy window arrangement enables use of laser apparatus directed external to the aircraft for target designation or other purposes while minimizing the amount of energy from such laser returning spuriously inside the cockpit where it inherently acts a noise signal for night vision equipment. The laser energy window limits the portion of the aircraft windshield or canopy exposed to laser radiation and its effects to a relatively small area, an obscurable area generating significantly reduced amounts of spurious return energy in comparison with use of the laser directly through an unlimited windshield, canopy, or other type of transparency.

Abstract: An efficient neural network computing technique capable of synthesizing two sets of output signal data from a single input signal data set. The method and device of the invention involves a unique integration of autoassociative and heteroassociative neural network mappings, the autoassociative neural network mapping enabling a quality metric for assessing the generalization or prediction accuracy of the heteroassociative neural network mapping.

Abstract: A ruggedized ultra high radio frequency antenna disposable at the rear of a hardened target penetrator warhead is provided. The antenna is usable for communicating signals from a transmitter in a deployed target penetrator warhead to a local repeater where retransmission to a more remote location can occur. The antenna includes a length-shortening and penetration abuse-resistant dielectric embedding material also supporting the subterranean signal communication to the local repeater function. Antenna radiating element fabrication from porous material such as screen wire and use of the dielectric material in a manner providing large G force tolerance and external dielectric variations are included.

Abstract: A micromechanical electrical systems (MEMS) metallic micromachined electrical switch usable on the die of an integrated circuit and inside the integrated circuit package for controlling radio frequency signal paths while incurring desirably small signal losses. The switch is of the single pole single throw mechanical type with provision for grounding one open-switch position node in the interest of limiting capacitance coupling across the switch in its open condition. Cantilever beam switch element suspension is included along with normally open and normally closed switch embodiments, electrostatic switch actuation and signal coupling through the closed switch by way of capacitance coupling. Low loss radio frequency operation above one gigahertz in frequency is provided.

Abstract: Multi-dimensional, non-linked method and apparatus for producing a simulated feeling of force on a preselected location on a human operator in a synthesized environment accomplished by generating a first, constant, stationary electromagnetic field and a second, varying electromagnetic field local to the human operator. The variance of the second electromagnetic field is controlled by electrical currents which are responsive to parameters describing the position and orientation of said preselected location on the human operator and such variance results in attraction and repulsion of the first and second electromagnetic fields emulating a feeling of force on the human subject.