Abstract: A controlled stochastic resonance circuit applies stochastic resonance to bias a nonlinear device with a control signal having a selected amplitude, frequency, and phase to enhance or suppress the response of the device to a periodic signal embedded in noise.

Abstract: An interactive overlay for displaying 3-D data of the present invention provides a method for analyzing 3-D data by superimposing an adjustable, semi-transparent bounding surface on a display of the 3-D data. The bounding surface makes visually apparent nulls on the 3-D data surface that fall below the selected value of the bounding surface. The bounding surface also provides a visual reference for estimating relative magnitudes.

Abstract: A masked signal transceiver of the present invention comprises a transmitter for transmitting a combined signal of a primary communications signal and an attenuated secondary communications signal occupying substantially the same frequency band concurrently. A receiver receives the combined signal and demodulates the primary communications signal to extract the primary communications signal information. An adaptive locally optimum processor separates the secondary communications signal from the combined signal. The secondary communications signal is then demodulated to extract the secondary communications signal information.

Abstract: A continuously variable beam combiner combines multiple input beams of different wavelengths into a single output beam in which the power of each input beam may be varied continuously.

Abstract: An optically controlled frequency selective surface (FSS) includes an electrically conductive layer having an array of radio frequency scattering elements such as slots formed in an electrically conductive layer or loops mounted to a substrate. Photonically controlled elements, such as photo-diodes, photo-transistors, and other photo-electronic devices, are connected across each of the scattering elements. Electromagnetic characteristics of the FSS, including resonant frequency, impedance, and the pass/stop band, may be modulated by controlling the degree of illumination of the photonically controlled elements.

Abstract: A signal quality measurement device of the present invention comprises a deviation function for determining a measured deviation value from envelope amplitude samples of a communications signal and a table function of deviation values versus signal-to-noise ratios computed from a statistical model of atmospheric noise for finding a signal-to-noise ratio that corresponds to the measured deviation value.

Abstract: The present invention provides a system for determining the deployed length of a flexible tension element such as cable which is wrapped in a pack and fed through a funnel. The element may be sensed using different types of sensors such as optical, acoustical or magnetic sensors. A sensor is mounted in a funnel flush with the inside funnel surface. As wraps of the flexible tension element are deployed, or pulled off from the pack, individual wraps of the flexible tension element pass across the face of a detector as the flexible tension element is displaced in a generally circular pattern around the inside of the funnel. Signal processing circuitry produces a signal indicating the presence of the flexible tension element within a predetermined distance of the sensor.

Abstract: A method for steering a beam of an antenna array minimizes a least squares approximation of an error function of a desired radiation pattern relative to an antenna array pattern calculated from a known radiation pattern for each antenna element.

Abstract: The invention integrates an amplifier directly into an electromechanical transducer assembly. In one embodiment of this invention, power from a power supply is supplied to what can be described as an electromechanical amplifier that includes bridge circuits that directly drive the transducer elements. Each transducer element can include its own co-located switching network, such as, for example, a bridge circuit, that can be used with other system components to control when and for how long a voltage of equal magnitude and of either a positive or negative polarity is selectively directed to the element to expand or contract it in relation to a signal desired to be acoustically transmitted. Besides permitting an output of two voltages of equal magnitude and opposite polarity, the bridge circuit also permits an output that is “open” and one that allows a dissipation of transducer element charge.

Abstract: A method for making electrical contacts and junctions in silicon carbide that concurrently incorporates and activates dopants from a gaseous ambient. The low temperature processing of the present invention prevents the formation of crystalline defects during annealing and preserves the quantitative chemical properties of the silicon carbide. Improved activation of dopants incorporated in a silicon carbide sample is provided for making the electrical contacts and junctions.

Abstract: A target detection device of the electromagnetic transmitter-receiver reaction type comprising a radio frequency oscillator which is integral with its radiating system and detector. It incorporates a pulse modulator which drives the oscillator to periods of high power transmission and a signal processing system to reject unwanted data and to effect detonation of the warhead at the optimum point on its trajectory.

Abstract: A liquid crystal array and associated drive circuitry are monolithically formed on a silicon-on-sapphire structure, and are fabricated by a method comprising the steps of: a) forming an epitaxial silicon layer on a sapphire substrate to create a silicon-on-sapphire structure; b) ion implanting the epitaxial silicon layer; c) annealing the silicon-on sapphire structure; d) oxidizing the epitaxial silicon layer to form a silicon dioxide layer from a portion of the epitaxial silicon layer so that a thinned epitaxial silicon layer remains; e) removing the silicon dioxide layer to expose the thinned epitaxial silicon layer; f) fabricating an array of pixels from the thinned epitaxial silicon layer wherein each of the pixels includes a liquid crystal capacitor; and g) fabricating integrated circuitry from the thinned epitaxial silicon layer which is operably coupled to modulate the pixels.

Abstract: A system for controlling the deglycerolization of red blood cells includes a cell sorter having multiple fluid channels each having a unique cross-sectional area for directing a fluid mixture consisting essentially of a saline solution and a plasma solution having glycerized red blood cell products through one or more of the fluid channels based on the sizes of the red blood cell products. An optical energy source illuminates the fluid mixture in the cell sorter, whereupon an optical detector generates a data signal in response to receiving light signals that propagate through the fluid mixture. A processor generates a control signal in response to receiving the data signal that is used by a servo-controlled device to control the ratio of the saline and plasma solutions in the fluid mixture so that the red blood cell products substantially flow only through one or more of the fluid channels having particular cross-sectional areas.

Abstract: A low friction surface is provided to hose-shaped acoustic envelopes for towed sonar arrays. The low friction surface permits multiple envelopes that are in intimate, parallel contact or that are crossed-over one another, to slide easily relative to one another, enhancing their deployment. The low friction surface is accomplished by blending particles of a low friction material with a base material. The mixture is heat extruded into pellets and the pellets are heat extruded into a hose of desired size. The exterior surface of the resulting hose is then subject to axially aligned abrasion to both expose the particles close to the exterior surface of the hose, and to create axially aligned micro-grooves in this surface. The micro-grooves allow water to enter and lubricate the boundary that is present, which is typically either another hose surface or the metal or other surface of an array deployment vehicle.

Abstract: A volumetric display comprises complementary segments made of a transparent material. An optical scattering layer is formed on a surface between adjoining segments. The segments are joined to form a display volume that may be rotated to cause the scattering layer to sweep out the entire display volume each revolution. A scanning beam may be used to illuminate points on the scattering layer at selected rotation angles to create a three-dimensional image.

Abstract: A method is presented for crystallizing a thin film on a substrate by generating a beam of pulsed optical energy, countouring the intensity profile of the beam, and illuminating the thin film with the beam to crystallize the thin film into a single crystal lattice structure.

Abstract: Processors which process baseband received signal sample amplitudes and ones which process baseband received sample phases are combined in a single general processor which cancels a greater variety of interference than any of the individual processors incorporated into it. This processor combines a wide-range of processors, for example, processors which filter baseband in-phase/quadrature sample amplitudes and phases. This general processor performs against any interferer as well as, or better than, the best of the processors it includes. The general processor assesses individual processor outputs and weights these so that those processors with the best interference suppressed outputs are utilized to form an interference suppressed output.

Abstract: A system is described which generates a wavelength stabilized output from a superluminescent diode. The system may be implemented whereby a superluminescent diode injects an optical signal into a conically tapered optical fiber fused to an optical fiber polarization independent wavelength division multiplexing (PINC WDM) coupler. The PINC WDM coupler transforms the optical signal into an optical signal which is wavelength stabilized with respect to temperature.

Abstract: A target detecting device which measures the range to the target and genees a variable d.c. voltage that is a function of the range. The range voltage is then applied to a time delay computer, along with range rate voltage, to permit a time delay computation which is a function of both the distance to the target and the missile-target closing velocity.

Abstract: A method for the fabrication of active semiconductor and high-temperature perconducting devices on the same substrate to form a monolithically integrated semiconductor-superconductor (MISS) structure is disclosed. A common insulating substrate, preferably sapphire or yttria-stabilized zirconia, is used for deposition of semiconductor and high-temperature superconductor substructures. Both substructures are capable of operation at a common temperature of at least 77 K. The separate semiconductor and superconductive regions may be electrically interconnected by normal metals, refractory metal silicides, or superconductors. Circuits and devices formed in the resulting MISS structures display operating characteristics which are equivalent to those of circuits and devices prepared on separate substrates.