Abstract: Nyquist folding receivers (NYFRs) are disclosed that use three or more non-modulated sampling clock signals with different frequencies to produce multiple projections in a sampled output. Using these three or more different sampling clock signals, multiple Nyquist zones are aliased together while still allowing signals from different Nyquist zones to be separated and identified in later processing based upon the sampling provided by the different sampling clock signals. NYFR sampling receivers are also disclosed that simultaneously produce multiple separate and different parallel channels from an input signal, with each different channel having a different sampling clock sampling rate from the other channels so as to generate a respective folding pattern that is different from the folding pattern generated by the respective RF sampling rate of each of the other simultaneous and parallel channels.

Abstract: A fusion night vision system has a plurality of hinged joints that allow an operator to adjust the distance between the left eye piece and the right eyepiece while allowing a row of pixels from a display to be maintained viewable through the right eye piece parallel with an imaginary line formed by an optical axis of the left eye piece with an optical axis of the right eye piece.

Abstract: A mainlobe detection process can include a number of tests that are performed to define when the monopulse antenna system will transition from open loop scanning to closed loop scanning and then to tracking. A hybrid tracking technique is also provided which adaptively discovers and corrects for phase alignment error. Magnitude-only tracking can be performed initially to locate the nulls in the azimuth and elevation ratios and to identify the magnitudes of these ratios at these nulls. Phase tracking can be then performed. During phase tracking, phase corrections can be repeatedly applied to the azimuth and elevation difference channels to correct any phase error that may exist. During this process, the magnitudes of the ratios can be used to determine how the phase corrections should be adjusted. Once the hybrid tracking process is complete, the monopulse antenna system is properly phase-aligned and phase tracking will be correctly employed.

Abstract: Methods and systems are disclosed to operate an aircraft with modified (e.g., improved) flight performance characteristics, such as increased or maximized aircraft takeoff weight and/or longer allowable mission time for the aircraft. In one example, the aircraft may be enabled to operate with increased aircraft engine performance (e.g., such as engine power) without increasing engine temperature above the maximum allowable operating temperature limits for the engine. In a further example, available engine power may be determined during a pre-flight sequence, and utilized by an aircraft without exceeding published or manufacturer specified engine temperature limits.

Abstract: A dual-spectrum photocathode capable of emitting photo-electrons into a first vacuum space includes a first photodetector array formed using a first optoelectronic material that generates photo-electrons responsive to incident electromagnetic energy in a first spectral band. The dual-spectrum photocathode also includes a second photodetector array formed using a second optoelectronic material that generates photo-electrons responsive to incident electromagnetic energy in a second spectral band that is different from the first spectral band. The first spectral band may include the visible electromagnetic spectrum between 390 nanometers and 700 nanometers and the second spectral band may include the short-wave infrared (SWIR) electromagnetic spectrum above 900 nanometers.

Abstract: Image intensifiers may include a photocathode that emits photoelectrons in proportion to the rate photons impact the photocathode. The photoelectrons are multiplied using a microchannel plate that includes a plurality of microchannels. Photoelectrons are scattered by the microchannel plate when the photoelectrons strike the surface of the microchannel plate rather than enter one of the microchannels. Electron scatter within an image intensifier results in a halo or bloom around bright or luminous objects. Halo or bloom may be minimized by reducing the electron scatter within the image intensifier. Deposition of an anti-scattering layer on the surface of the microchannel plate within the image intensifier can absorb photoelectrons that fail to enter a microchannel and may thus reduce the incidence of halo or bloom.

Abstract: A power electronics unit for driving an electric machine excited by permanent magnets and including a rotor and a stator having at least one stator winding, comprising at least one power switch designed to drive the stator winding, and an overvoltage protection device to protect the power switch from overvoltage. The overvoltage protection device comprises a phase voltage detecting device associated with the power switch as well as a short-circuit switching circuit which, when a predetermined phase voltage threshold value of the phase voltage detected by the phase voltage detection device is reached or exceeded, is adapted to be activated for short-circuiting the stator winding associated with the power switch. The short-circuit switching circuit comprises the power switch designed to drive the stator winding.

Abstract: Embodiments include different multi-port ring combiners which are configured to act as multi-output signal routers. One type of multi-port ring combiner includes input ports that are driven by pairs of outphasing signals. The multi-port ring combiner also includes multiple channels that are independently routed to a first output, to a second output, or to a third output, according to a phase relationship of the multi-port ring combiner. The multi-port ring combiner enables an outphasing signal combination which provides output port selection. The multi-port ring combiner may be a 4-port ring combiner, a 5-port ring combiner or a 6-port ring combiner.

Abstract: A mainlobe detection process can include a number of tests that are performed to define when the monopulse antenna system will transition from open loop scanning to closed loop scanning and then to tracking. A hybrid tracking technique is also provided which adaptively discovers and corrects for phase alignment error. Magnitude-only tracking can be performed initially to locate the nulls in the azimuth and elevation ratios and to identify the magnitudes of these ratios at these nulls. Phase tracking can be then performed. During phase tracking, phase corrections can be repeatedly applied to the azimuth and elevation difference channels to correct any phase error that may exist. During this process, the magnitudes of the ratios can be used to determine how the phase corrections should be adjusted. Once the hybrid tracking process is complete, the monopulse antenna system is properly phase-aligned and phase tracking will be correctly employed.

Abstract: The disclosure relates to an emissive display configured to operate in a day mode and a night mode. The emissive display comprises a day pixel configured to operate in the day mode. The emissive display also comprises a night pixel configured to operate in the night mode, wherein the night pixel is not operational in the day mode. The emissive display also comprises a common pixel configured to operate in both the day mode and the night mode. The emissive display also comprises a detector configured to selectively change an operating mode of the display between the day mode and the night mode based on a detected indication.

Abstract: A monopulse antenna system can include a monopulse detector assembly (MDA) that is configured to steer a monopulse antenna based on the magnitude of an elevation ratio or azimuth ratio independently of the phase of the ratio. To prevent the direction of the monopulse antenna from being changed too frequently, the MDA can employ ratio bins to determine when the direction of the monopulse antenna should be reversed. Also, the MDA may enforce a hold period during which a change in the direction of the monopulse antenna will not be performed. The MDA can employ one or more mapping equations to generate a steering signal as a function of the magnitude of the ratio. The mapping equations can be selectively employed based on whether tracking is being performed at or near the ratio null.

Abstract: A monopulse tracker includes multiple dual-axis monopulse antenna systems that are angled with respect to one another. The orientations of the monopulse antenna systems create a much larger field of view for the monopulse tracker to eliminate the need to steer the monopulse tracker. The monopulse tracker can be configured to estimate a position of an object based on tracking information received from more than one monopulse antenna system therefore increasing the accuracy of the estimated position. The multiple monopulse antenna systems can be arranged in a low-profile housing to facilitate use of the monopulse tracker on aircraft.

Abstract: A battery-powered system comprising: 1) a housing adapted to contain electro-mechanical machines; and 2) an apparatus disposed within the housing. The apparatus comprises: i) a battery configured as an annular cylinder having an inner diameter, an outer diameter, and a length; and ii) a cylindrical device disposed within a cavity formed by the annular cylinder of the battery. An outer diameter of the cylindrical device is substantially the same as the inner diameter of the battery and the cylindrical device has a length substantially equal to the length of the battery. The cylindrical device may be a fluid reservoir or a second battery.

Abstract: A fusion night vision system has a plurality of hinged joints that allow an operator to adjust the distance between the left eye piece and the right eyepiece while allowing a row of pixels from a display to be maintained viewable through the right eye piece parallel with an imaginary line formed by an optical axis of the left eye piece with an optical axis of the right eye piece.

Abstract: A permutation apparatus can receive a data block of ordered data elements in parallel data segments that are Pin number of data elements wide. The permutation apparatus can perform a parallel-to-parallel conversion and one or more reorder operations on the data elements and output the data block in parallel data segments that are Pout number of data elements wide and in which at least some of the data elements are reordered. The Pin-parallel-data segments can be clocked into the permutation apparatus on successive cycles of a clock, and the Pout-parallel-data segments can be clocked out of the permutation apparatus on cycles of the same clock.

Abstract: Systems, methods, and non-transitory computer-readable media taught herein process a subset of a three-dimensional array of voxels to form an image of a region of interest in an object. Images thus formed are clear, comprehensible, and contextual. The systems, methods, and non-transitory computer-readable media taught herein select the subset of voxels that represent the region of interest along a direction perpendicular to a view direction defined by the region of interest. The subset of voxels represents one or more portions of a plurality of image slices of the object.

Abstract: A fault-tolerant display system includes a TFT panel, a first driver couplet including a first gate driver and a first source driver, and a second driver couplet including a second gate driver and a second source driver. The first gate driver and the second gate driver feed into the LCD panel from opposite directions and the first source driver and the second source driver feed into the LCD panel from opposite directions. The first driver couplet and the second driver couplet each have their own independent power supplies, independent from one another. In this way, individual pixels of the LCD panel are driven simultaneously by two pairs of source drivers and gate drivers, such that if one of the driver pairs fails due to some fault, the other driver pair can continue to drive the LCD panel without loss of information despite the failure of the one driver pair.

Abstract: A mainlobe detection process can include a number of tests that are performed to define when the monopulse antenna system will transition from open loop scanning to closed loop scanning and then to tracking. A hybrid tracking technique is also provided which adaptively discovers and corrects for phase alignment error. Magnitude-only tracking can be performed initially to locate the nulls in the azimuth and elevation ratios and to identify the magnitudes of these ratios at these nulls. Phase tracking can be then performed. During phase tracking, phase corrections can be repeatedly applied to the azimuth and elevation difference channels to correct any phase error that may exist. During this process, the magnitudes of the ratios can be used to determine how the phase corrections should be adjusted. Once the hybrid tracking process is complete, the monopulse antenna system is properly phase-aligned and phase tracking will be correctly employed.

Abstract: An enhanced vision system includes an image intensifier that includes a phosphor screen. The phosphor screen includes a thin-film phosphor layer deposited, patterned, transferred, or otherwise disposed on the substrate using a thin-film deposition technique. A conductive layer is deposited across at least a portion of the phosphor layer. The relatively smooth morphology of the phosphor layer beneficially permits the use of a relatively thin conductive layer. The use of a relatively thin conductive layer advantageously reduces the operating voltage between an electron multiplier and the phosphor screen. A secondary electron emitter may be disposed across at least a portion of the conductive layer.

Abstract: An antenna array can be quickly and efficiently designed to meet specified performance criteria. A system can be configured to receive various performance criteria as inputs, and from these inputs, identify how elements of an antenna array should be arranged so that the antenna array will meet the performance criteria. An iterative process can be performed to identify at least one arrangement of elements that will best meet the performance criteria while also complying with specified structural constraints.