General Dynamics Mission Systems, Inc.

A method for controlling a free space optical receiver including receiving an optical signal including a digital information by an optical terminal, detecting a phase and an amplitude of the optical signal, generating an optical local oscillator signal in response to the phase and amplitude, extracting an optical baseband signal in response to a superposition of the optical signal and the optical local oscillator signal, converting, by a photodiode, the optical baseband signal into a digital baseband signal, and extracting, by a digital signal processor, the digital information from the digital baseband signal.

Optical signal detectors, systems including the detectors, and methods of using the detectors and systems are provided. The optical signal detector may include an aperture for receiving an optical signal, an optical signal sensor having separate photodiodes each configured to be irradiated with portions of the optical signal directed from the aperture, detect the portions of the optical signal impinging therewith, and generate analog signals therefrom, logarithmic amplifiers each configured to receive the analog signals from a corresponding one of the photodiodes of the optical signal sensor, perform logarithmic amplification of the received analog signals, and generate logarithmic analog signals from the analog signals.

The present disclosure relates to a hybrid quantum sensor and method for detecting electromagnetic signals using the unique properties of Rydberg atoms and electrically small apertures. The sensor comprises an electrically small antenna that is non-resonant at a detection frequency that generates a concentrated electric field within a defined volume.

Signal handling capability of multi-layer printed circuit board is improved by placing anti-pad regions around dangling stub via portions and then enlarging the size of the placed anti-pad regions to reduce capacitive coupling of the via with other structures on the circuit board. Controlled enlargement of via size is based on calculation of electromagnetic coupling simulated from component placement data from the electronic circuit board design-automation tool's data store. Spectral power density calculated by three-dimensional electromagnetic field solver provides a visual indication of the signal handling improvement as the anti-pad size is increased.

The data capture system, coupled to the emergency response system, captures speech utterances from incoming callers and uses those utterances to construct embeddings representing the captured speech utterances, the embeddings collectively representing a latent vector space and being stored in a data store within computer readable media. The query system communicates with the data store and provides an interface accessible to the call center operators that alerts a call center operator—substantially while an incoming emergency call is being received—the number of times a voice print substantially matching that of the incoming caller has been heard by the emergency response system before, or other useful metadata such as dispositions of past calls with substantial matches of the caller's voice.

The receiver captures an electromagnetic transmission carrying a bauded signal, such as a transmission from an orbiting satellite, and processes it for Doppler shift analysis. The electromagnetic transmission is captured and a non-linear operation is performed to expose a cyclostationary feature of the captured transmission that will define a rate-line. This rate-line will exist at a frequency that is related to the bauded signal and Doppler shift relative to the motion of the transmitter to the receiver. The rate-line frequency is tracked in time to generate data indicative of a Doppler shift associated with the satellite and processed by an estimator fed by satellite propagator to supply positioning, navigation and timing services at the receiver output.

A method includes receiving data of an image of a circuit pattern having multiple circuit pattern slices, and providing the data to a light projector aimed toward at least one light-sensitive material over a substrate of an object. The method also includes generating a patterned light-sensitive material, including projecting at least one temporal sequence of frames from the light projector. Each frame within a single temporal sequence has an image of a different one of the circuit pattern slices and projected so that each circuit pattern slice forms a contour line on the light-sensitive material. The method includes moving the light projector, the substrate, or both after an individual frame projection so that each contour line in the same temporal sequence is formed at a different location on the at least one light-sensitive material. The patterned light-sensitive material is used to pattern a conductive material over the substrate.

The classical channel employs a transmit laser and classical modulator. The quantum channel employs a nonlinear medium and spontaneous parametric down conversion producing quantum entangled signal and idler photon pairs which are encoded. The classical and quantum channels are combined to define a propagated hybrid signal. The receiver splits the hybrid signal on basis of wavelength into classical and quantum channels. The quantum receiver employs optical parametric amplification, supplied with energy from a second harmonic generation device synchronized to the classical carrier wavelength. A photodetector and extracts a quantum message from the quantum signal.

The waveguide carrying a nonlinear crystal with reflective interface, a pump photon source and a circulator define an optical parametric amplifier which uses optical power from the pump photons to boost incoming signal and idler photons which carry the encoded signal. The nonlinear crystal performs optical parametric amplification upon the incoming optical signal in a quantum photonic process that generates additional signal and idler photons to thereby boost the intensity of the incoming signal. A photodetector is coupled for communication with the third port and operative to convert the reflected optical signal into an electrical signal defining the output of the communications receiver.

The multi-wavelength phase stabilization system employs a broadband light source producing a continuous range of wavelengths that include the plurality of discrete optical wavelengths corresponding to the wavelengths to be stabilized. An interferometric mixing system receives the broadband light and the wavelengths to be stabilized, producing a plurality of interference patterns associated with the discrete optical wavelengths. A detecting system produces plural electrical signals based on the intensity of the interference patterns and feeds a control system which produces phase lock-in control signals based on feedback from the electrical signals. A phase shifting system driven by the control system independently adjusts each of the plural discrete optical signals to a stabilized phase, such that the plural discrete optical signals are phase-stabilized to a common reference point.