Abstract: Methods, apparatus, and computer readable storage medium for authenticating assertions of a source are disclosed. In one aspect, a method for authenticating an assertion of a source in an environment of distributed control include receiving a notification of the assertion; determining an entity responsible for maintaining an authenticated list of assertions by the source based on a first trusted public record, determining an assertion authenticator for the entity based on a second trusted public record, determining one or more assertions of the source from the assertion authenticator, and authenticating the assertion based on the determined one or more assertions.

Abstract: Radiation is directed at an object, and radiation scattered by the object is sensed. An angular distribution of scatter in the sensed scattered radiation relative to a path of the radiation directed at the object is determined, and the angular distribution is evaluated. One or more atomic numbers, or effective atomic numbers, of materials composing the object is determined based on evaluating the angular distribution.

Abstract: Frontside-illuminated barrier infrared photodetector devices and methods of fabrication are disclosed. In one embodiment, a frontside-illuminated barrier infrared photodetector includes a transparent carrier substrate, and a plurality of pixels. Each pixel of the plurality of pixels includes an absorber layer, a barrier layer on the absorber layer, a collector layer on the barrier layer, and a backside electrical contact coupled to the absorber layer. Each pixel has a frontside and a backside. The absorber layer and the barrier layer are non-continuous across the plurality of pixels, and the barrier layer of each pixel is closer to a scene than the absorber layer of each pixel. A plurality of frontside common electrical contacts is coupled to the frontside of the plurality of pixels, wherein the frontside of the plurality of pixels and the plurality of frontside common electrical contacts are bonded to the transparent carrier substrate.

Abstract: An NVIS-compatible backlight assembly for an LCD display comprising a short-wavelength (blue) light source positioned in a first layer and a photoluminescent layer positioned adjacent the first layer for transforming blue monochrome emission from the blue light source into tri-color light for use as a full-color light source, while minimizing radiance in NVIS-sensitive regions.

Abstract: A system and method for imaging objects with a sparse detector array that includes fewer detectors than conventional x-ray scanning systems. The sparse detector array is positioned to receive x-ray radiation from the at least one x-ray source after passing through an inspection area. The sparse detector array includes a plurality of rows of detector elements, wherein at least some of the plurality of rows are separated by gaps such that the at least some of the plurality of rows are non-contiguous. An iterative reconstruction process is used to determine a volumetric image of the object from the radiation measurements recorded by the detectors in the sparse detector array.

Abstract: A system and method for enabling transmission of a stepped-frequency radar signal can involve a first antenna and a second antenna. The system can also involve receiving circuitry configured to receive detected reflections from the antennas and to generate data including information associated with frequency and phase shifts. The system can further involve a processor configured to receive the generated data from the receiving circuitry and to analyze the generated data to determine information associated with a moving object located at a side of a wall opposite to the system by differentiating reflections of the transmitted signal detected with the first antenna from reflections of the transmitted signal detected with the second antenna.

Abstract: A transmit antenna or antennas can be configured to transmit a composite orbital angular momentum (OAM) radio frequency (RF) beam comprising a plurality of individual OAM RF signals each having a different OAM mode. An array of antennas for receiving and resolving the composite OAM beam into the individual OAM signals can be located entirely within a relatively small sector of a far field pattern of the composite OAM beam. A processing module connected to the antennas of the receive array can resolve the composite OAM beam into its individual OAM signals using angular resolution. The transmit antenna can transmit the individual OAM signals—and thus the composite OAM beam—as full OAM signals or partial-beam OAM signals.

Abstract: An imaging system exposes an object within a region to a beam of penetrating radiation. The beam of penetrating radiation is sensed on a side opposite the region from a source of the beam. An attenuation of the beam caused by passing the beam through the object is determined, the attenuation is compared to a threshold attenuation. If the attenuation exceeds the threshold attenuation, a parameter of the imaging system is adjusted based on the determined attenuation.

Abstract: A cluster of communications platforms can comprise a master platform and support platforms. The master platform can partition a data block into data partitions and transmit the data partitions via a short range transmitter to the support platforms. Each support platform can include a high power storage device for powering long range burst transmissions of a subset of the data partitions to a distant receiver. Burst transmissions of data partitions by the same support platform can be separated by a charging time period that allows a high power storage device in the support platform to charge from a relatively low average power Pa a relatively high power burst PB that is sufficient to transmit one of the data partitions to a distant receiver.

Abstract: A handheld communications device is created with a touch sensitive display, a secure computing component, and a non-secure computing component. The secure component may comprise a secure CPU executing a secure operating system. The non-secure component may comprise a separate non-secure CPU executing a separate non-secure operating system. The touch sensitive display on the handheld communications device is divided into a secure portion and a non-secure portion such that information displayed in the secure portion is provided by the secure operating system, and information displayed in the non-secure portion is provided by the non-secure operating system. Similarly, data entered through the secure portion of the display is provided to the secure operating system, and data entered through the non-secure portion of the display is provided to the non-secure operating system.

Abstract: A radio signal transmission technique includes selecting a sample rate from a plurality of predefined sample rates so that the radio signal is contained entirely within a Nyquist zone corresponding to the sample rate. A digitized signal is converted to an analog signal, spectrally enhanced, and passed through a selected one of a plurality of selectable bandpass filters to form the radio signal.

Abstract: The perceived sample rate at which a DAC can operate can be increased by allowing multiple DACs to process different portions of a digital signal in parallel. In this way, the outputs of multiple DACs can be combined into a single analog signal to achieve the desired speeds and resolutions of the analog output. This parallel processing can be implemented using a time-interleaving technique or a sub-band reconstruction technique. Pre-distortion can be applied to the digital input signal to compensate for degradation detected in the analog output signal. By applying pre-distortion, waveforms having high sampling rates can be efficiently generated.

Abstract: A drive unit for an aircraft ground wheel associated with a brake unit for braking the ground wheel includes: a driving motor drivingly coupleable to the ground wheel; and a cooling system including at least a drive cooling unit configured to generate a drive cooling air stream for cooling the drive unit and a brake cooling unit configured to generate a brake cooling air stream by sucking in air from the brake unit. A method of controlling such drive unit in which the cooling system is driven by the driving motor of the drive unit includes: decoupling the driving motor from the ground wheel and increasing the rotational speed of the driving motor to increase the amount of generated drive cooling air, when an operating condition of the ground wheel and/or of the drive unit is switched from a propulsion mode to a non-propulsion mode.

Abstract: A novel magnetron achieves increased power output at high frequencies by replacing a typical resonant cavity with a slow-wave waveguide structure. Waveguides built into the anode body sustain oscillations having phase change coefficients of 2*pi*n radians per section, where n is a positive integer. The magnetron is capable of supporting RF oscillations at frequency harmonics of the fundamental frequency, permitting it to operate at frequencies double or quadruple that of a similarly sized conventional magnetron.

Abstract: A return-to-zero control signal for controlling a modulator can be generated from two separate streams. A first data stream can include a pulse for each logical one that appears in an input data stream, while a second data stream can include a pulse for each logical zero that appears in the input data stream. The first and second data streams can be combined in a manner that yields the return-to-zero control signal. The first and second data streams can be generated in digital circuitry, such as an FPGA, to minimize the analog path for generating the return-to-zero control signal.

Abstract: A thermal absorption structure of a radiation thermal detector element may include an optically transitioning material configured such that optical conductivity of the thermal absorption structure is temperature sensitive and such that the detector element absorbs radiation less efficiently as its temperature increases, thus reducing its ultimate maximum temperature.

Abstract: A cluster of communications platforms can comprise a master platform and support platforms. The master platform can partition a data block into data partitions and transmit the data partitions via a short range transmitter to the support platforms. Each support platform can include a high power storage device for powering long range burst transmissions of a subset of the data partitions to a distant receiver. Burst transmissions of data partitions by the same support platform can be separated by a charging time period that allows a high power storage device in the support platform to charge from a relatively low average power Pa a relatively high power burst PB that is sufficient to transmit one of the data partitions to a distant receiver.

Abstract: An improved Horizontal Situation Indicator (HSI) module for use with an aircraft, wherein the HSI module is adapted for accepting Bank Angle Commands or waypoint data from the GPS flight module and for using the same to determine a heading error. The HSI module is further adapted for outputting the heading error to the Flight Director module where it can be used to create a Roll Command for output to the Auto-Pilot, whereby the Auto-Pilot can be commanded to follow a turn using the HSI and the Flight Director without requiring an additional module be added to the aircraft to create the heading error for use by the Flight Director. The waypoint data can be of the “flyover” type or the “flyby” type.

Abstract: The invention relates to a method of producing a rotor (10) of an electric machine, the rotor (10) comprising a rotor body (14) adapted to be rotated about a rotor axis (A) as well as at least one rotor component (16) to be mounted to the rotor body (14), said method comprising the steps of: arranging the rotor component (16) on the rotor body (14) and winding a wire-like structure (20) around an outer circumference (12) of the rotor body having the rotor component (16) arranged thereon so as to form a bandage (18), with the wire-like structure (20) during winding thereof being held under an adjustable bias.

Abstract: A radio frequency (RF) horn can include an interior surface with an inner geometry comprising irregular, aperiodic corrugations and/or undulations. The pattern of the inner geometry can excite higher order modes simultaneously in two RF signals each at a different frequency that combine with fundamental modes of the signals to produce substantially Gaussian profiles of the two signals at the output aperture of the horn. Even though the signals are at different frequencies, the illumination pattern of both signals on a reflector antenna at which the horn is directed can be substantially the same.