Abstract: A resonator fiber optic gyroscope (RFOG) is disclosed that reduces rotation rate error instability. In one embodiment, the RFOG comprises a resonator optical ring cavity, a first light source in optical communication with the ring cavity and configured to generate a clockwise optical signal, and a second light source in optical communication with the ring cavity and configured to generate a counter-clockwise optical signal. The RFOG also includes a first optical component in optical communication with the first light source and the ring cavity. The first optical component is configured to prevent the clockwise optical signal from being back-reflected to the first light source. A second optical component is in optical communication with the second light source and the ring cavity. The second optical component is configured to prevent the counter-clockwise optical signal from being back-reflected to the second light source.

Abstract: A method of forming a semiconductor structure is provided. One method comprises forming a device region between a substrate and a bond pad. Patterning a conductor between the bond pad and the device region with gaps. Filling the gaps with insulation material that is harder than the conductor to form pillars of relatively hard material that extend through the conductor and forming an insulation layer of the insulation material between the conductor and the bond pad.

Abstract: A method and system for compressing coefficients of a digital filter is provided. In one approach, the method comprises providing a digital filter having a plurality of consecutive filter coefficients including a first filter coefficient, determining consecutive difference values between each of the consecutive filter coefficients, and storing the first filter coefficient and the consecutive difference values in a memory. The consecutive filter coefficients are generated by retrieving the first filter coefficient, and adding a first difference value to the first filter coefficient to generate a consecutive second filter coefficient. The first difference value corresponds to a difference between the first filter coefficient and the second filter coefficient. A consecutive next difference value is then added to the second filter coefficient to generate a consecutive next filter coefficient.

Abstract: An optical component is provided. The optical component includes an optical-path portion including an arm-connecting portion and a lower portion, a first arm extending from a first end of the arm-connecting portion, and a second arm extending from a second end of the arm-connecting portion. The first arm has at least one resting feature and the second arm has at least one resting feature. The optical-path portion has an input surface. When the resting features of the first arm and the second arm are positioned on a top surface at short edges of a trench in a trench system, the optical-path portion is vertically aligned in the trench.

Abstract: A method for operating a communications bus between a first computer and a second computer is provided. The method comprising monitoring a receiver bus coupled to the first computer for activity and confirming that the communications are determinant. The communications are confirmed by receiving a control label on the receiver bus and acknowledging to the second computer through a transmitter bus coupled to the first computer that communications are determinant. The method also comprises enabling the second computer to access data accessible by the first computer when the reliability of communications is confirmed.

Abstract: Systems and methods for improved digital RF transport in a DAS are provided. In one embodiment, a transceiver comprises: a receive path circuit including an RF reception interface coupled to an ADC, the ADC receiving a down-converted analog RF spectrum from the RF reception interface and producing a digitized RF spectrum at an input sampling rate; a logic device receiving the digitized RF spectrum and producing a first set of baseband data samples at a first sampling rate, corresponding to a first spectral region of the analog RF spectrum and a second set of baseband data samples at a second sampling rate, corresponding to a second spectral region of the analog RF spectrum. The logic device maps the first set and second sets of baseband data samples to a respective first set and second set of timeslots of a serial data stream transport frame.

Abstract: Systems and methods for potted shock isolation are provided. In once embodiment a shock isolation system comprises an isolator comprising an outer ring for mounting to an external housing, and an inner ring connected to the outer ring via an isolating element; and an inertial sensing assembly comprising: at least one circuit board secured to the inner ring of the isolator, the at least one circuit board further comprising a triad of gyroscopes and a triad of accelerometers; and a low durometer highly dampened supporting material encapsulating a first surface of the at least one circuit board.

Abstract: A gyroscope system comprises a gyroscope block having a plurality of cavities and a plurality of passages that define a path; a plurality of mirrors each located in one of the plurality of cavities; at least one mirror drive coupled to one of the plurality of mirrors and configured to change a position of the respective mirror, wherein the path's length is changed by the change in the position of the respective mirror; a dither system coupled to the gyroscope block and configured to induce an angular rotation of the gyroscope block; and a controller configured to provide a dither signal indicative of a dither frequency to the dither system and a path length control (PLC) signal indicative of a PLC frequency to the at least one mirror drive. The controller is configured to calculate the PLC frequency as a function of the dither frequency.

Abstract: Systems and methods of carrier frequency acquisition or recovery in a receiver. The receiver is able to achieve carrier acquisition when a frequency offset is large (e.g., near a decision boundary). The receiver includes a demodulator, an equalizer, and a carrier recovery module. The carrier recovery module includes a decision device and phase detector, a phase error differentiator, a frequency direction confidence module, and a frequency and phase combiner module. The carrier recovery module calculates a phase error differential between a phase error at a first time and a phase error at a second time. Based on the phase error differential, the frequency direction confidence module generates a frequency offset confidence number. The frequency offset confidence number provides an indication of the direction of a frequency offset and a degree of certainty related to a detected direction (e.g., positive or negative) of the frequency offset.

Abstract: Systems and methods for radar altimeter antenna performance monitoring via reflected power measurements are provided. In one embodiment, a single antenna radar altimeter comprises: an antenna; a circulator coupled to the antenna; a transmitter coupled to the circulator; a receiver coupled to the circulator; wherein the circulator provides coupling of the transmitter and the receiver to the antenna while providing isolation between the transmitter and the receiver; a reflected power monitor positioned between the circulator and receiver; and a processor coupled to the reflected power monitor via a first analog-to-digital converter, the processor configured to compute and track reflected power measurement statistics from data generated by the reflected power monitor and provide a performance output indicating when one or more of the reflected power measurement statistics exceed a predetermined deviation threshold.

Abstract: System and methods of increasing reliability of determined location information by using two integration filters are provided. An exemplary embodiment integrates inertial navigation system information and global navigation satellite system (GNSS) information in a real time Kalman filter; determines a real time location of the aircraft with the real time Kalman filter based upon the INS information and the GNSS information; delays the GNSS information by an interval; integrates the INS information and the delayed GNSS information in a delay Kalman filter; determines a predictive location of the aircraft with the delay Kalman filter based upon the INS information, the delayed GNSS information, and the interval; and in response to an inaccuracy of the real time location determined from the real time Kalman filter, selects the predictive location determined from the delay Kalman filter as a new real time location of the aircraft.

Abstract: A method and system for redundancy management is provided for a distributed and recoverable digital control system. The method uses unique redundancy management techniques to achieve recovery and restoration of redundant elements to full operation in an asynchronous environment. The system includes a first computing unit comprising a pair of redundant computational lanes for generating redundant control commands. One or more internal monitors detect data errors in the control commands, and provide a recovery trigger to the first computing unit. A second redundant computing unit provides the same features as the first computing unit. A first actuator control unit is configured to provide blending and monitoring of the control commands from the first and second computing units, and to provide a recovery trigger to each of the first and second computing units. A second actuator control unit provides the same features as the first actuator control unit.

Abstract: Systems and methods for reducing rotation sensing errors in a resonator fiber optic gyroscope. An example method propagates a primary light wave through a resonator having an optical fiber and a plurality of optical surfaces for directing the light wave exiting a first end of the optical fiber back into an opposite end of the optical fiber. The optical fiber is wound onto a piezo-electric transducer (PZT) tube. A sinusoidal voltage is applied to the PZT tube to modulate a length of a fiber cavity within the optical fiber. The amplitude and frequency of the fiber cavity length modulation is selected to produce a relative phase modulation between the primary light wave and a double-back reflected light wave, such that the rotation sensing errors resulting from double backscatter of light is at a frequency above a frequency band of interest. This allows the associated error to be filtered out of the rotation rate signal.

Abstract: System and methods for managing I/O throughput for large scale computing systems are provided. In one embodiment, an operating system for a computer system having a processor, a memory and at least one data storage device is provided. The operating system comprises: an operating system kernel; at least one filesystem controlling access to the at least one data storage device; and a toolkit module installed within the operating system kernel. The toolkit module monitors input/output (I/O) calls communicated via a datapath between at least one software application being executed on the processor and the filesystem. The toolkit module inserts one or more tools into the datapath, the one or more tools each executing a predefined function based on observation of a first set of the I/O calls being communicated in the datapath.

Abstract: A power generation system that comprises a first power generator; a first turbine operable to drive the first power generator; a vaporizer operable to vaporize a working fluid, wherein the vaporized working fluid turns the first turbine; and a condenser operable to condense the vaporized working fluid exiting the first turbine, wherein the condenser is coupled to the vaporizer such that the condensed working fluid is vaporized in the vaporizer. The power generation system also comprises a second power generator; a second turbine operable to burn a fuel to drive the second power generator; a switch to selectively operate the second turbine independently of the first turbine; and a heat exchanger coupled to the second turbine to receive flue gas from the second turbine when operated, wherein heat is transferred in the heat exchanger from the flue gas to the vaporized working fluid after the vaporized working fluid exits the vaporizer and prior to the vaporized working fluid entering the first turbine.

Abstract: A method of communicating among vehicles in a convoy or otherwise in close proximity is provided. The method includes initiating an internet protocol layer on a wireless hub of a first vehicle. The first vehicle also synchronizes with at least a one other vehicle having a wireless hub. A voice signal is received at the first vehicle. The voice signal is then converted into packets. Finally, the packets are sent from the wireless hub of the first vehicle to the wireless hub of the at least one other vehicle using a networking protocol.

Abstract: A rotational bar code is presented. The rotational bar code includes a structure at least a portion of which includes a cylindrical surface having at least one of an outward-facing surface and an inward-facing surface, and a plurality of vertically-oriented symbols horizontally abutted in a non-periodic unique pattern on one of the outward-facing surface or the inward-facing surface. The surfaces are radially disposed about a rotational axis of the cylindrical surface. The vertically-oriented symbols are unique for at least a predefined segment of an arc of the cylindrical surface. An angular orientation of the cylindrical surface is identifiable based on the plurality of vertically-oriented symbols.

Abstract: A system comprises at least one inertial sensor operable to provide inertial sensor data during a trip; a processing unit coupled to the at least one inertial sensor, the processing unit operable to calculate navigation data based on the inertial sensor data and to estimate error in the inertial sensor data, wherein the processing unit is further operable to adjust subsequent inertial sensor data received during the trip from the at least one inertial sensor in order to compensate for the estimated error; and a memory coupled to the navigation unit and operable to store data between power cycles; wherein the processing unit is further operable to calculate a current trip error estimate from a plurality of error estimates during the trip and to estimate a repeatability error component based on the current trip error estimate and previous trip error estimates stored in the memory; wherein the repeatability error component is stored in the memory, the processing unit being further operable to update inertial sen

Abstract: A communication module is provided. The module includes at least one transceiver, a filter, a power amplifier, an enclosure, an internal interface and an external interface. The power amplifier is in communication with the at least one transceiver and filter. Moreover, the at least one transceiver, filter and power amplifier are tuned and calibrated to work with each other. The enclosure is configured to physically retain the at least one transceiver, filter and power amplifier. The internal interface is configured to interface connections between the at least one transceiver and the power amplifier and the external interface configured to provided external connections to the module. In addition, the external interface is coupled to the internal interface.

Abstract: An Interferometric Fiber Optic Gyro (IFOG) device for high accuracy sensing. An example IFOG includes an integrated optics chip (IOC) and a modulation component that modulates one or more light signals passing thru the IOC according to a bias-modulation waveform. A glitch pattern experienced at front-end components of the IFOG includes frequency content that has approximately zero amplitude at predefined sense harmonics. Frequency content of the bias-modulation waveform is below a predefined threshold value at the predefined sense harmonics.