Abstract: An adaptive cascaded electronic protection processing system for global navigation satellite system (GNSS) threat mitigation is provided. The system includes a precorrelation characterization component configured to provide at least one parameter characterizing a plurality of received signals. A correlator is configured to provide a plurality of correlation results, each representing one of the plurality of received signals. A spatial weight contribution component is configured to determine an optimal set of digital beam-forming weights via an optimization process according to the at least one parameter. A postcorrelation characterization component is configured to determine at least one constraint on the optimization process according to the plurality of correlation results.

Abstract: One embodiment of the invention includes a magnetometer system. The system includes a sensor cell comprising alkali metal particles and a probe laser configured to provide a probe beam through the sensor cell. The system also includes a detection system configured to implement nuclear magnetic resonance (NMR) detection of a vector magnitude of an external magnetic field in a first of three orthogonal axes based on characteristics of the probe beam passing through the sensor cell and to implement electron paramagnetic resonance (EPR) detection of a vector magnitude of the external magnetic field in a second and a third of the three orthogonal axes based on the characteristics of the probe beam passing through the sensor cell. The system further includes a controller configured to calculate a scalar magnitude of the external magnetic field based on the magnitude of the external magnetic field in each of the three orthogonal axes.

Abstract: An adaptive cascaded electronic protection processing system for global navigation satellite system (GNSS) threat mitigation is provided. The system includes a precorrelation characterization component configured to provide at least one parameter characterizing a plurality of received signals. A correlator is configured to provide a plurality of correlation results, each representing one of the plurality of received signals. A spatial weight contribution component is configured to determine an optimal set of digital beam-forming weights via an optimization process according to the at least one parameter. A postcorrelation characterization component is configured to determine at least one constraint on the optimization process according to the plurality of correlation results.

Abstract: One embodiment of the invention includes a magnetometer system. The system includes a sensor cell comprising alkali metal particles and a probe laser configured to provide a probe beam through the sensor cell. The system also includes a detection system configured to implement nuclear magnetic resonance (NMR) detection of a vector magnitude of an external magnetic field in a first of three orthogonal axes based on characteristics of the probe beam passing through the sensor cell and to implement electron paramagnetic resonance (EPR) detection of a vector magnitude of the external magnetic field in a second and a third of the three orthogonal axes based on the characteristics of the probe beam passing through the sensor cell. The system further includes a controller configured to calculate a scalar magnitude of the external magnetic field based on the magnitude of the external magnetic field in each of the three orthogonal axes.

Abstract: One embodiment of the invention includes an accelerometer sensor system. The system includes a sensor comprising a proofmass and electrodes and being configured to generate acceleration feedback signals based on control signals applied to the electrodes in response to an input acceleration. The system also includes an acceleration component configured to measure the input acceleration based on the acceleration feedback signals. The system further includes an acceleration controller configured to generate the control signals to define a first scale-factor range associated with the sensor and to define a second scale-factor range associated with the sensor. The control system includes a calibration component configured to calibrate the accelerometer sensor system with respect to range-dependent bias error based on a difference between the measured input acceleration at each of the first scale-factor range and the second scale-factor range.

Abstract: One embodiment of the invention includes an accelerometer sensor system. The system includes a sensor comprising a proofmass and electrodes and being configured to generate acceleration feedback signals based on control signals applied to the electrodes in response to an input acceleration. The system also includes an acceleration component configured to measure the input acceleration based on the acceleration feedback signals. The system further includes an acceleration controller configured to generate the control signals to define a first scale-factor range associated with the sensor and to define a second scale-factor range associated with the sensor. The control system includes a calibration component configured to calibrate the accelerometer sensor system with respect to range-dependent bias error based on a difference between the measured input acceleration at each of the first scale-factor range and the second scale-factor range.

Abstract: A fiber optic gyroscope (FOG) is provided. The FOG comprises a depolarizer that receives light from a light source, a multifunction integrated optic chip (MIOC) and a sensing coil coupled to outputs of the MIOC. The FOG also includes a polarizer coupled between an output of the depolarizer and an input of the MIOC. The polarizer mitigates polarization non-reciprocity (PNR) bias error and enhances the polarization extinction ratio (PER) of the FOG.

Abstract: A system is provided for the continuous reduction, in real time, of bias in a force rebalanced accelerometers having a proof mass coupled to an accelerometer housing by a flexure suspension. The system comprises a closed loop, force rebalance servo that provides control voltage to the proof mass to null an electrical pickoff signal that indicates the motion of the proof mass with respect to the accelerometer housing, wherein a time varying disturbance signal is injected into the force rebalance servo that results in the generation of a time varying voltage in the output of the force rebalance servo that corresponds to a magnitude of the net positive spring of the combined flexure suspension and electrostatic springs acting on the proofmass. The system also comprises a negative electrostatic spring servo that applies a negative electrostatic spring DC voltage to each of a pair of negative electrostatic forcer electrodes.

Abstract: One embodiment includes a sensor system. The system includes a cell system comprising a pump laser configured to generate a pump beam to polarize alkali metal particles enclosed within a sensor cell. The system also includes a detection system comprising a probe laser configured to generate a probe beam. The detection system can also be configured to calculate at least one measurable parameter based on characteristics of the probe beam passing through the sensor cell resulting from precession of the polarized alkali metal particles in response to an applied magnetic field. The system further includes an AC Stark shift control system configured to frequency-modulate the pump beam and to control a center frequency of a frequency-modulated pump beam based on the characteristics of the probe beam passing through the sensor cell to substantially stabilize and mitigate the effects of AC Stark shift on the at least one measurable parameter.

Abstract: Systems and methods are provided for a correlator system. The system includes a plurality of numerically controlled oscillators and a multiplier configured to receive an input stream representing a received signal. A carrier multiplexer is configured to select between respective outputs of at least two of the plurality of numerically controlled oscillators and provide the selected output to the multiplier. A code generator is configured to provide a replica code. A delay component is configured to provide a delayed code from the replica code. A code multiplexer is configured to selectively provide each of the delayed code and the replica code to the multiplier.

Abstract: In one embodiment, a system includes a motion detector to determine a motion event or a no motion event for an inertial system. The determination of the events is based upon comparing at least one motion parameter in the inertial system to at least one predetermined threshold. An azimuth update controller (AUC) periodically requests motion detection events from the motion detector and corrects heading information to a previous positional state in the inertial system in response to receipt of the no motion event.

Abstract: One embodiment of the invention includes a material detection system. The system includes a sensor system configured to collect radiation from a region of interest. The collected radiation can include a plurality of frequency bands. The system also includes a processing unit configured to detect a material of interest. The material of interest can be a concealed dielectric material, and the processing unit can be configured to decompose the collected radiation into natural resonance signals to analyze the natural resonance signals to detect an anomaly corresponding to the concealed dielectric material based on wave characteristics of the natural resonance signals. The processing unit could also include processing layers associated with the plurality of frequency bands for detecting and identifying the material of interest based on wave characteristics associated with each of the plurality of frequency bands of the collected radiation.

Abstract: One embodiment of the invention includes an atom beam gyroscope system. The system includes an atom beam system that generates an atom beam comprising alkali metal atoms along a length of a detection region orthogonal to a sensitive axis. The system also includes a detection system comprising a detection laser and photodetector. The detection laser can generate an optical detection beam that illuminates the detection region to pump the alkali metal atoms. The photodetector can measure an optical absorption of the optical detection beam by the alkali metal atoms in the atom beam and to generate an intensity signal associated with the measured optical absorption. The system further includes a gyroscope sensor configured to calculate rotation of the atom beam gyroscope system about the sensitive axis based on a magnitude of the intensity signal due to a Doppler-shift in energy of the alkali metal atoms in the atom beam.

Abstract: A system includes a light source that generates a coherent output signal. A light stabilizer comprising an optical fiber can be configured to pass one axis of propagation of the coherent output signal from the light source to a Bragg grating to generate a stabilized pump output signal for the system.

Abstract: One embodiment of the invention includes an atomic sensing system. The system includes an atomic sensing device configured to generate an output signal along an output axis in response to a plurality of control parameters. The system also includes a signal generator configured to apply a reference signal to a cross-axis that is approximately orthogonal to the output axis. The system also includes a phase measurement system configured to demodulate the output signal relative to the reference signal to measure a relative phase alignment between the output axis and a physical axis of the atomic sensing device based on the reference signal.

Abstract: One embodiment includes an adaptive sample quantization system. The adaptive sample quantization system includes an antenna to receive a radio frequency (RF) signal having data encoded therein, and analog antenna electronics configured to convert the RF signal to an analog electrical signal. The system also includes an analog-to-digital converter (ADC) directly coupled to the antenna and configured to generate a plurality of consecutive digital samples of the RF signal. The system further includes a quantizer to determine a mode based on the plurality of consecutive digital samples and to select at least one threshold based on the determined mode. The quantizer can further compare each digital sample with the at least one threshold to generate a corresponding one of a plurality of output samples having a reduced number of bits relative to the respective digital sample to substantially mitigate potential interference and facilitate extraction of the data.

Abstract: In one embodiment, a system includes a motion detector to determine a motion event or a no motion event for an inertial system. The determination of the events is based upon comparing at least one motion parameter in the inertial system to at least one predetermined threshold. An azimuth update controller (AUC) periodically requests motion detection events from the motion detector and corrects heading information to a previous positional state in the inertial system in response to receipt of the no motion event.

Abstract: One embodiment of the invention includes a material detection and/or identification system. The system includes an electromagnetic (EM) sensor system configured to collect EM radiation from a region of interest. The collected EM radiation could comprise orthogonally-polarized EM radiation. The system also includes a processing unit configured to detect and identify a material of interest in the region of interest. As an example, the processing unit could measure reflectivity data associated with a material of interest based on the collected EM radiation and calculate a refractive index of a material of interest based on the measured reflectivity data, such that the material of interest is identified based on the refractive index. The processing unit can also be configured to calculate a surface roughness associated with the material, such that the refractive index can be calculated based on the surface roughness associated with the material.

Abstract: An aspect of the present invention relates to system and method for substantially obstructing magnetic flux. One aspect of the present invention provides an apparatus for substantially obstructing at least one magnetic flux path between an ambient space and a protected volume. The apparatus includes an inner shield, substantially enclosing the protected volume. The inner shield has at least one inner shield aperture extending therethrough to allow external access to the protected volume. An outer shield substantially encloses the inner shield. The outer shield has at least one outer shield aperture extending therethrough to allow internal access from the ambient space. The apparatus is configured to impede magnetic flux between at least one inner shield aperture and at least one outer shield aperture.

Abstract: A method for registering a radar system. The method includes obtaining first values for a location of a target relative to the radar system using radar system initiated signals, obtaining geo-referenced location data for and from the target, obtaining second values for the location of the target relative to the radar system using the geo-referenced location data, computing location registration bias errors for the radar system using the first and second values, and registering the radar system using the computed location registration bias errors.