Abstract: A system and method for combining and radiating electromagnetic energy. The invention includes a novel antenna comprising a first dielectric substrate having opposite first and second surfaces, a patch of conducting material disposed on the first surface, a ground plane of conducting material disposed on the second surface, and at least three input ports, each input coupled to the patch at a feed point. The feed points are positioned to minimize the total power reflected from each input port. In an illustrative embodiment, the feed points are equally distributed around a circle having the same center as the patch and having a radius chosen to minimize the reflections at each input. In accordance with the novel method of the present invention, the outputs of multiple sources are combined in the antenna itself, by coupling the sources directly to the antenna.

Abstract: A winged vehicle includes an elongated fuselage, and a wing mechanism affixed to the fuselage. The wing mechanism has a wing-support-body track affixed to and extending lengthwise along the fuselage, a translating wing-support body engaged to and translatable along the wing-support-body track, and exactly two deployable cantilevered wings. Each deployable cantilevered wing has a wing pivot mounted to the translating wing-support body so that the deployable cantilevered wing is pivotable about the translating wing-support body. The two deployable cantilevered wings are each pivotable between a stowed position and a deployed position. An actuation mechanism is operable to controllably move the translating wing-support body along the wing-support-body track and to controllably move the two deployable cantilevered wings between the stowed position and the deployed position.

Abstract: An infrared imaging system uses an uncooled elliptical surface section between reflective surfaces to allow a detector to perceive a cold interior of a vacuum chamber rather than a warmer surface of a structure or housing. In this way, background infrared radiation from within the system may be minimized.

Abstract: A gas-expansion cooler assembly has an expansion structure with an expansion orifice and an expansion reservoir in fluid-flow communication with an expansion-orifice outlet. A heat exchanger has a heat-exchanger inlet, and a heat-exchanger outlet in fluid-flow communication with the expansion-orifice inlet. The heat exchanger includes at least two heat-exchanger plates stacked in a facing relationship along an assembly axis. Each heat-exchanger plate includes an in-plane channel lying substantially in a plane perpendicular to the assembly axis. The in-plane channels of the adjacent heat-exchanger plates are in fluid-flow communication with each other and with the expansion-orifice inlet to form a continuous high-pressure fluid-flow path from the heat-exchanger inlet to the expansion-orifice inlet. The heat exchanger further includes an axial channel extending parallel to the assembly axis.

Abstract: An oscillator. In the illustrative embodiment, the oscillator includes an ortho-mode feed; a reflective amplifier array adapted to be illuminated by the feed with an input wavefront with a first polarization and to return thereto an amplified wavefront with a second polarization orthogonal to the first wavefront; and a partially reflective plate disposed between the feed and the amplifier. The inventive oscillator provides a Fabry-Perot cavity between the feed and the plate. In the illustrative embodiment, the plate is a polarized plate. The plate may have surfaces with dissimilar polarizations and/or curvatures. The amplifier may be phase locked by an ortho-mode converter or other arrangement.

Abstract: In some pseudo-orthogonal waveform embodiments, a radar system transmits pseudo-orthogonal waveforms and performs multiple correlations on a combined single receiver channel signal. In some quadratic polyphase waveform embodiments, a radar system may simultaneously transmit frequency separated versions of a single quadratic polyphase waveform on a plurality of transmit antennas, combine the return signal from each antenna into a combined time-domain signal, and perform a Fourier transformation on the combined time-domain signal to locate a target. The radar system may identify a target, such as sniper's bullet, incoming projectile, rocket-propelled grenade (RPG) or a mortar shell. In some embodiments, the system may estimate the target's trajectory to intercept the target. In some embodiments, the system may estimate the target's trajectory and may further extrapolate the target's trajectory to locate the target's source, such as the sniper.

Abstract: A system includes a dome window and an optical system having a central optical path that passes through the dome window. The optical system includes a refractive optical element having an axis of symmetry which passes through the optical element and which is tilted relative to the central optical path at a location where the central optical path and the axis of symmetry intersect within the optical element.

Abstract: On-chip multispectral imaging and data management is provided in the form of an Adaptive Focal Plane Array (AFPA) that is capable of spectral tunability at the pixel level. Layers of photonic crystals are registered with pixels of a broadband focal plane array. Spectral tuning is accomplished by switching the photonic crystal layers on/off and/or by changing their material structure to tune their photonic band gaps and provide a passband for incident photons. The photonic crystal layers are preferably segmented to independently address different regions or “cells” of pixels down to a pixel-by-pixel resolution. The AFPA may simultaneously sense different regions of a scene at different spectral wavelengths, spatial resolutions and sensitivities.

Abstract: An ultra-wideband receiver system includes an intelligent-preselector stage to up-convert received signals to signals within a first IF frequency-range with stepped first oscillation signals, a first down-converting stage to down-convert the signals within the first IF frequency-range to signals within a second IF frequency-range with a fixed second oscillation signal, and a second down-converting stage to down-convert the signals within the second IF frequency-range to signals within a third IF frequency-range with stepped third oscillation signals. The center frequency of the first IF frequency-range may be at least 30% to 35% higher than a highest frequency in the receive-frequency range to provide an image frequency far from (e.g., more than twice) the highest frequency in the receive-frequency range. The receiver may also include a synthesizer to generate the first, second and third oscillation signals with half-integer frequency dividers based on a master reference signal.

Abstract: An area-protection system uses an active-array antenna to generate a high-power millimeter-wave wavefront to deter an intruder within a protected area. One or more reflectors may be positioned within the protected area to help retain energy of the wavefront within the area. The area-protection system may include an intrusion-detection subsystem to detect presence of the intruder within the protected area and to generate a detection signal. The active-array antenna may generate the high-power millimeter-wave wavefront in response to the detection signal. In some embodiments, the intrusion-detection subsystem may detect the presence of a tag worn by the intruder, and may instruct the array antenna to refrain from generating the wavefront when tag is authenticated. In some embodiments, an illuminator may be used detect intruder movement based on return signals. In some embodiments, the array antenna includes semiconductor wafers arranged together on a substantially flat surface.

Abstract: A directed-energy system includes a plurality of non-coherent microwave sources and a plurality of antennas. Each antenna may be coupled to a corresponding one or more of the sources to radiate energy from the sources and cumulatively generate high-energy pulses based on statistical combining of the energy radiated from the antennas. The pulses may statistically occur at an average rate approximately equal to a frequency spread between the sources divided by twice a number of sources comprising the plurality. In some embodiments, the sources may separately generate horizontally and vertically polarized energy to separately generate high-energy pulses from the statistical combining of the horizontally and vertically polarized energy. In some embodiments, the frequency spread between the sources may be controlled to change the average rate at which the pulses statistically occur. In some embodiments, the frequency spread between the sources may be controlled to change a pulse-width of the pulses.

Abstract: An electromagnetic coil gun system includes a launcher having a barrel with a longitudinal bore therethrough, and a plurality of longitudinally extending electrical excitation coils arranged circumferentially around the bore of the barrel so that a magnetic field produced by an electrical current in each electrical excitation coil penetrates into the bore. Each electrical excitation coil is independently activated by the electrical current passed therethrough. There is a projectile sized to be received within the bore of the barrel and having a circumferential armature at a tail end thereof, and a nose end.

Abstract: An edge detection system and method implement a recursive polar algorithm process to generate an edge image from an input image. The edge detection system may include a polar filter to recursively perform low-pass filtering along edge contours of a gradient pixel grid and generate a gradient image output. An edge thinner may be included to find gradient field peaks along a direction of gradient vectors of the gradient image output and generate thinned gradient pixels. An edge path segmenter may group the thinned gradient pixels into edge segments, and a segment classifier may determine whether the edge segments are edge paths or clutter. The edge detection system and method may improve automated image processing in medical diagnostics, reconnaissance, missile guidance, hazard or threat warning systems, security systems, access control systems (e.g., face recognition), navigation, geographic mapping, manufacturing quality inspection, robot vision, and search and rescue.

Abstract: Systems and methods of tracking a beam-aspect target are provided. In embodiments, a target is tracked with a Kalman filter while detections are received. After a detection is missed, the Kalman filter may be concurrently propagated with a blind-zone particle filter until a probability that the target is in a blind zone exceeds a threshold. When the probability exceeds the threshold, the Kalman filter may refrain from further propagating. After a gated detection is received, the blind-zone particle filter and an unrestricted-zone particle filter may be concurrently propagated while a probability that the target is in an unrestricted zone exceeds a threshold. The system may return to tracking with the Kalman filter when a covariance of the unrestricted-zone particle filter falls below a predetermined covariance.

Abstract: An optical system includes a window having a nonspherically curved outer surface and a curved inner surface, and a transmission optical corrector adjacent to the curved inner surface of the window. The transmission optical corrector has a selectively nonuniform passive transmission optical property, such as a spatially varying index of refraction of the transmission optical corrector or a spatially varying diffractive property of the transmission optical corrector. The optical system further has an optical train positioned such that the transmission optical corrector lies between the curved window and the optical train. A sensor is disposed to receive the optical ray passing sequentially through the window, the transmission optical corrector, and the optical train.

Abstract: A control system includes a rate-damping loop that uses a calculated angle-of attack error to non-linearly scale a rate-feedback signal so that at lower angle-of attack (AOA) error values, an acceleration feedback term plays a greater role in pitch compensation, while at greater angle-of-attack error values, a rate-feedback term plays a greater role in the pitch compensation. In some embodiments, a control system and method of controlling an angle-of-attack of a moving body are provided. A signal representing an angle-of-attack error is non-linearly combined with a signal representing a rate-of-change of an estimated angle-of-attack to generate a non-linear rate-damping signal. The non-linear rate-damping signal is subtracted from the signal representing the angle-of-attack error to generate a signal to control one or more elements of the moving body.

Abstract: A non-traditional, non-uniformity compensation processor. In the illustrative embodiment, the feedforward adaptive non-uniformity compensation processor includes a multiplier which receives a video image and generates a compensated video image by multiplying the video signal by one of a noise reducing constant or one. The inventive processor further includes a shunting multiplication processor which supplies a selected one of the noise reducing constant or one to the multiplier in response to the presence of one of fixed pattern noise (FPN) and temporal noise (TN) in adjacent frames of the video image. In an illustrative embodiment, the inventive system cones the output of an FPA to generate a coned output signal. The system isolates the FPN in the coned output signal and feedforward processes the coned output signal on a pixel-by-pixel basis to generate a FPN-reduced output signal.

Abstract: A bias-line bypassing structure comprises a plurality of bias-line bypass circuits forming a periodic structure at least partially around each of a plurality of amplification units to reduce RF current flow between the amplification units and a grid-bias network. Each bias-line bypass circuit may comprise thin-film capacitors, inductive wire bridges, and thin-film resistors connected to ground vias. The thin-film capacitors may have differing values selected to resonate with an associated one of the inductive wire bridges and an associated one of the thin-film resistors to shunt RF current flow over a range of RF frequencies. In some embodiments, the inductive wire bridges may comprise inductive wire-bridge fuses to provide an open circuit in case an associated one the thin-film capacitors shorts to ground. The bias-line bypass circuits may be positioned along a bias street of the grid-bias network and spaced apart by less than a quarter-wavelength of an effective propagation constant of the bias line.

Abstract: A position encoder uses a track encoded with a pattern of bit-widths in accordance with a sequence. The sequence may be any sequence having unique subsequences, and may be a pseudo-random noise (PRN) sequence such that each N-bit subsequence occurs only once on the track. Sensors detect transitions between the bits and bit-widths as the track moves with respect to the sensors to provide in-phase and quadrature-phase pick-off signals. The pickoff signals are summed and absolute value thresholded. The absolute value thresholded sum signal is sampled when the quadrature pairs are in the “00” or “11” quadrants, and latched when the sum signal goes high to distinguish between wide and narrow bit widths. The latch is shifted into a shift data register for use in determining the position of the encoder track. In the case of a PRN sequence having a length of 2N bits, the position may be an absolute position when the number of valid bits in the shift data register is at least N.

Abstract: A plurality of sensor vehicles collect imaging data from an assigned location of a target region having targets and non-targets. The imaging data may be combined based on its location and the combined data is matched to a threat object map to identify the actual targets from the non-targets. In some embodiments, the sensor vehicles may be redirected to collect velocity and/or range information on the identified targets.