Abstract: A gapless Vivaldi notch/meander line antenna is provided having a top plate with a Vivaldi notch, a cavity and a rearwardly-extending notch, with the top plate having integral side plates and a meander line bridging the rearwardly-extending notch at its distal end.

Abstract: A technique is provided that uses a dual mode seeker (IR and LADAR) for precise target dynamics measurement, which extends stripping to a much higher altitude than ground based radar. Initial results show that this approach works to altitudes in excess of 100 km. Stripping becomes a reliable way to discriminate lighter weight decoys from reentry vehicles at altitudes and ranges consistent with planned divert capabilities for terminal phase missile defense. It is a finding of this invention that the LADAR will improve the spatial resolution by a factor of five over typical missile defense IR seekers using a common aperture. The LADAR provides a 3D angle, angle, range (AAR) image for each laser pulse which is used to extract the precise target state vectors.

Abstract: A single dual mode monolithic focal plane array having an active sensor and a passive sensing capability is switched from one mode to the other by switching the bias across the cells of the array from a passive IR mode to an active LADAR mode, with the monolithic dual mode focal plane array having applications in missile target seekers and laser target designators. The switching is accomplished by increasing the gain of the array by as much as 30 times that associated with IR detection when laser return pulses are expected. Thus, there need be no mechanical changes to the array to afford both passive IR sensing and an active LADAR pulse detector. Nor need there be two different focal plane arrays, one for IR and one for laser radiation, which leads to boresighted alignment problems.

Abstract: An apparatus and method for detecting gases, gasified agents or other analytes. The apparatus includes a solid body having a first surface area and a second surface area. A first, preferably polymeric, coating is superimposed on the first surface area of the solid body. A second, preferably polymeric, coating is superimposed on the second surface area of this solid body. The first coating and the second coating are different materials which adsorb different agents at different rates. A wave propagating transducer is positioned adjacent the solid body to propagate a first wavefront adjacent the first surface area of the solid body. This wave propagating transducer also propagates a second wavefront adjacent the second surface area of the solid body. These first and second wavefronts interfere to produce an interference pattern which is unique to the particular agent which is adsorbed by the first and second coatings.

Abstract: A system is provided for nulling out or eliminating alignment errors in an optical system by moving a lens to capture and center a collimated beam laterally-shifted by thermal excursions, thus to couteract the boresight error caused by the thermally-induced lateral shifting. As a result, alignment error the thermal coefficient of expansion characteristics of the optical elements and their mounting systems caused by lateral off-sets is corrected by moving a lens or lens system in response to thermal changes in a direction which moves the lens so that the collimated light impinging on the lens is made to come in on the optical axis of the lens.

Abstract: For those optical waveguides that require the deposition of a thick film and a high-temperature anneal to create an appropriate waveguide medium, wafer warping, bowing or dishing is reduced or eliminated by depositing a film of the same thickness on the backside of the wafer so as to relieve film stress during the deposition and annealing process. In one embodiment the waveguide medium is silicon oxynitride, although other depositable thick films may be utilized in place of the silicon oxynitride.

Abstract: The combination of a Vivaldi notch and a meander line loaded antenna for ultra wide bandwidth is provided with dual polarity by providing orthogonally oriented Vivaldi notched structures coupled to each other at the edges thereof. Mode selection is provided by selectively switching between linear and circular polarization modes through selective input coupling techniques. Each side of the dual polarity Vivaldi notch/MLA plates includes a bifurcated plate with one end of the bifurcated plate having exponentially curved Vivaldi notch surfaces ahead of a cavity opened at the rear end to the bifurcated notch. The side plates for the top plate structure are themselves Vivaldi notch structure, with their side plates being the ajoining top or bottom plate. In each case, internally carried meander lines connect the adjacent together.

Abstract: A system is presented that provides real-time performance for iterative multi-user detectors, such as Turbo MUDs, which are used to separate simultaneous transmissions on the same frequency, by permitting the MUD to use a less computationally intense, fast-processing algorithm and to correct for errors caused by the fast processing. In order to reduce the errors, a voting system is coupled to the output of the multi-user detector within the iterative system. The voting system provides confidence values on a bit-by-bit basis for the estimates made by the multi-user detector, with the confidence values then being utilized as soft inputs to a bank of conventional single-user decoders.

Abstract: Combined Vivaldi notch and meander line loaded antennas are concatenated in an array to provide an ultra wideband antenna having a decreased low frequency cut-off due to the concatenation. In the concatenation process, plates of adjacent antennas are shared so that one plate is used for both of the adjacent antennas. In a preferred embodiment, the side plates and the top and bottom plates are identically configured.

Abstract: In a dual mode target designation system involving the use of a passive IR detector for developing rough target locations and a ladar or laser range finder for refining target position, a closed loop system is provided for correcting the boresight error of the laser so that it matches that of the IR detector. In one embodiment this is accomplished by first selecting a target detected by the IR detector, executing a laser scan in which the laser beam is moved in a reach pattern until a return from the selected target is detected, developing an error vector between the reported laser target position and the reported IR detector target position and repositioning the line of sight of the laser using the error vector to minimize the co-boresighting error. The result is that the boresight correction resulting from illuminating the first target reduces laser scan time for each subsequent target to permit rapid and accurate target position acquisition.

Abstract: A wideband meander line loaded antenna is configured to be flush mounted to a conductive surface serving as a ground plane by embedding the meander line components within a conductive cavity surrounded at its top edge by the ground plane. The antenna thus looks out of a cavity recessed in the surface. By permitting flush mounting the meander line antenna, not only can the antenna dimensions be minimized due to the use of the meander line loaded antenna configuration, but in aircraft applications no part of the antenna exists above the skin of the aircraft, thereby to minimize turbulent flow. Moreover, when adapted to wireless handsets or laptop computers, the depth or thickness of the unit need not be increased when providing a wideband antenna, thus to minimize the overall dimensions of the device.

Abstract: A nested cavity embedded loop mode antenna is provided with an ultra wide band response by nesting individual embedded cavity meander line loaded antenna modules, with the meander lines coupled to a ground plane plate either capacitively or directly so as to provide as much as a 27:1 ratio of high frequency to low frequency cutoff. The nested meander line structure is exceptionally compact and eliminates the problem of a null in the antenna radiation pattern perpendicular to the face of the antenna, thus to provide a loop type antenna pattern at all frequencics across which the antenna is to be operated. The use of the nested meander line configuration provides a flush mount for the antenna having a footprint associated with the larger of the meander line cavities and thus the lowest frequency of operation, the nesting precluding the necessity of providing separate side-by-side meander line loaded antennas which would increase the real estate required.

Abstract: A method for manufacturing sidewall contacts for a chalcogenide memory device is disclosed. A first conductive layer is initially deposited on top of a first oxide layer. The first conductive layer is then patterned and etched using well-known processes. Next, a second oxide layer is deposited on top of the first conductive layer and the first oxide layer. An opening is then etched into at least the first oxide layer such that a portion of the first conductive layer is exposed within the opening. The exposed portion of the first conductive layer is then removed from the opening such that the first conductive layer is flush with an inner surface or sidewall of the opening. After depositing a chalcogenide layer on top of the second oxide layer, filling the opening with chalcogenide, a second conductive layer is deposited on top of the chalcogenide layer.

Abstract: A cavity-backed wideband slimline flat panel antenna array for providing a steerable beam includes an array of slot antennas, each of which fed by its own individual dipole radiator, with the wide bandwidth being due to the matching impedances of the slot antenna and dipole radiator across the entire frequency band. In one embodiment, an upstanding printed circuit balun feed is connected to each dipole. The dipole elements are located to either side of a slot, and are arrayed on the underneath side of a dielectric layer under the substrate into which the slots are formed, with the dipole elements directly fed by individual upstanding printed circuit baluns which are arrayed beneath the individual slots antennas. The use of the dipole elements, in addition to providing a wider operational bandwidth, also permits feeding each of the slots without having to use striplines which would have to cross each other and therefore not work.

Abstract: A system for calibrating airborne direction finding antenna arrays eliminates the problem of trying to maintain a constant depression angle when flying an airplane directly over a calibration antenna to collect deep depression angle data. The deep depression angle data necessary for calibration is provided by data from a scale model of the aircraft having a direction-finding array which simulates the actual direction-finding array on the aircraft. In order to collect deep depression angle data, the model is pivoted through 360° while maintaining a controlled depression angle. Thus, it is unnecessary for calibration to actually fly a plane to attempt to obtain deep depression angle measurements. In the subject system, only a single depression set of data is required from the aircraft. Thus, with the exception of baseline shallow depression angle data from this plane, the calibration data comes strictly from the scale model, which is much more easily obtained.

Abstract: A grounding device for water vehicles. The device includes an elongated electrical conductive section. The device also includes an elongated rope for increasing water resistance positioned in an adjacent relation to the elongated electrical conductive section. The device is of particular usefulness in grounding RF transmitters on high speed water vehicles having electrically insulative hulls.

Abstract: A modified V-groove structure in a double clad laser system permits multiple emitter side pumping of a fiber laser. In one embodiment, a stack of at least five emitters have individual outputs coupled into the inner cladding, with as many sources as desired coupled to the fiber to raise the cumulative pumping power to in excess of 2-KW, thus to achieve a 1-KW fiber laser.

Abstract: A method for deflecting a projectile from an initial trajectory. Such a projectile has a first surface area and a second surface area and moves through a gaseous atmosphere with a surrounding plasma sheath. This method includes the step of directing electromagnetic radiation toward the projectile, wherein the electromagnetic radiation has a wavelength which is absorbed by the plasma sheath but is not substantially absorbed by the gaseous atmosphere.

Abstract: An apparatus for reducing switching regulator noise from outputs of multiple switching regulators is disclosed. The apparatus includes an operational amplifier, an capacitor, a resistor and a pair of diodes. The switching regulators are connected in series to provide a positive output rail and a negative output rail. The output of the operational amplifier in connected to an inverting input of the operational amplifier and a positive sensing input of one of the switching regulators. The non-inverting input of the operation amplifier is connected to the positive output rail of one of the switching regulator via the capacitor. The resistor is connected between a positive voltage output of one of the switching regulators and the capacitors. The pair of diodes is connected between the positive voltage output of one of the switching regulators and the negative output rail of the switching regulators.

Abstract: A decoy deployment and retrieval system includes an extensible boom and corresponding cradle or saddle for use in the retrieval of the towed decoy such that, upon retrieval, the extensible boom with its decoy captured in the cradle is retracted into a chamber so that the decoy can be deployed over and over again. In one embodiment, the decoy is both towed by, and controlled over, a fiber optic line in which a load cell is used to detect tension on the line to prevent damage, and a fiber optic rotary joint is utilized along with high voltage slip rings to permit electrical and optical coupling without backlash, fouling or damage to the line.