Abstract: Shortwave infrared (SWIR) hyperspectral imaging (HSI) systems comprise a supercontinuum laser source configured to illuminate objects and a receiver comprising a spectrometer configured to receive light reflected from the objects. In some cases, hyperspectral images can be created by raster scanning of the source/receiver across a scene. The supercontinuum laser source provides active illumination to allow collection of hyperspectral imagery during day (including overcast conditions) and night.

Abstract: Shortwave infrared (SWIR) hyperspectral imaging (HSI) systems comprise a supercontinuum laser source configured to illuminate objects and a receiver comprising a spectrometer configured to receive light reflected from the objects. In some cases, hyperspectral images can be created by raster scanning of the source/receiver across a scene. The supercontinuum laser source provides active illumination to allow collection of hyperspectral imagery during day (including overcast conditions) and night.

Abstract: Embodiments relate to a free space optical (FSO) terminal that transmits and receives (e.g., data-encoded) optical beams. The FSO terminal includes a fore optic (e.g., telescope) and a chromatic Risley prism pair. A receive (Rx) optical beam is received through the fore optic, and a transmit (Tx) optical beam is transmitted through the fore optic. The chromatic Risley prism pair is positioned along the optical paths of both the Rx and Tx optical beams. Since the Rx and Tx optical beams have different wavelengths and the chromatic Risley prism pair has a wavelength dependence, the chromatic Risley prism pair creates an angular separation between the Rx and Tx optical beams. A controller controls the Risley prism pair (and possibly also the wavelength of the Tx optical beam) to achieve a desired angular separation between the Rx and Tx optical beams in free space.

Abstract: Embodiments relate to a local free space optical (FSO) terminal that transmits and receives optical beams. The FSO terminal includes a fore optic and a dispersive optical component. A receive (Rx) optical beam from a remote FSO terminal is received and focused by the fore optic to a Rx spot at a focal plane of the fore optic. A transmit (Tx) optical beam with a different wavelength forms a Tx spot at the focal plane and is collimated and projected by the fore optic to the remote FSO terminal. The dispersive optical component is positioned along optical paths of both the Rx beam and the Tx beam. Among other advantages, a wavelength dependence of the dispersive optical component laterally separates the Rx spot and the Tx spot at the focal plane.

Abstract: Shortwave infrared (SWIR) hyperspectral imaging (HSI) systems comprise a supercontinuum laser source configured to illuminate objects and a receiver comprising a spectrometer configured to receive light reflected from the objects. In some cases, hyperspectral images can be created by raster scanning of the source/receiver across a scene. The supercontinuum laser source provides active illumination to allow collection of hyperspectral imagery during day (including overcast conditions) and night. Additionally, the hyperspectral imaging systems can use range-gated imaging.

Abstract: Embodiments relate to a local free space optical (FSO) terminal that transmits and receives optical beams. The FSO terminal includes a fore optic, an optical relay system, and an actuator system. The fore optic focuses a receive (Rx) beam to a Rx spot on a focal plane of the fore optic. The focal plane also includes a Tx spot formed by a transmit (Tx) optical beam, however the Rx and Tx spots are laterally separated at the focal plane. The optical relay system creates a conjugate spot for the Rx or Tx spot so that the Rx and Tx fibers may be axially separated. Due to the axial separation, the actuator system can adjust a lateral separation of the Rx and Tx fibers to account for point ahead of the local FSO communication terminal.

Abstract: A local free space optical (FSO) terminal senses an external environment that includes at least two beacons transmitted from a remote FSO terminal. The local terminal is configured to sense the beacons at a frame rate. Each beacon comprises a pulse train with pulses that are transmitted at a pulse rate. The pulse trains are temporally offset relative to each other so that pulses from at least one of the pulse trains do not fall across frame boundaries during sensing, regardless of a temporal location of the frame boundaries. In addition to detecting the at least two beacons, the local terminal is configured to identity the beacon that contains pulses that do not fall across the frame boundaries, and adjust its orientation based on the identified beacon.

Abstract: Embodiments relate to a local free space optical (FSO) terminal that transmits and receives optical beams. The FSO terminal includes a fore optic and a dispersive optical component. A receive (Rx) optical beam from a remote FSO terminal is received and focused by the fore optic to a Rx spot at a focal plane of the fore optic. A transmit (Tx) optical beam with a different wavelength forms a Tx spot at the focal plane and is collimated and projected by the fore optic to the remote FSO terminal. The dispersive optical component is positioned along optical paths of both the Rx beam and the Tx beam. Among other advantages, a wavelength dependence of the dispersive optical component laterally separates the Rx spot and the Tx spot at the focal plane.

Abstract: Embodiments relate to a local free space optical (FSO) terminal that transmits and receives optical beams. The FSO terminal includes a fore optic, an optical relay system, and an actuator system. The fore optic focuses a receive (Rx) beam to a Rx spot on a focal plane of the fore optic. The focal plane also includes a Tx spot formed by a transmit (Tx) optical beam, however the Rx and Tx spots are laterally separated at the focal plane. The optical relay system creates a conjugate spot for the Rx or Tx spot so that the Rx and Tx fibers may be axially separated. Due to the axial separation, the actuator system can adjust a lateral separation of the Rx and Tx fibers to account for point ahead of the local FSO communication terminal.

Abstract: Shortwave infrared (SWIR) hyperspectral imaging (HSI) systems comprise a supercontinuum laser source configured to illuminate objects and a receiver comprising a spectrometer configured to receive light reflected from the objects. In some cases, hyperspectral images can be created by raster scanning of the source/receiver across a scene. The supercontinuum laser source provides active illumination to allow collection of hyperspectral imagery during day (including overcast conditions) and night.

Abstract: Embodiments relate to a high power supercontinuum (SC) fiber optical source. The SC fiber optical source includes a prebroadening optical fiber that broadens the spectrum of a lower power intermediate optical signal before final amplification. The spectrum broadening creates spectral components which facilitate further spectrum broadening of amplified signal in final nonlinear stage, allowing to achive flatter and wider spectrum, and reduces nonlinear Stimulated Brillouin Scattering (SBS) that could damage SC fiber optical source components or limit the output power of the SC fiber optical source signal, thus enabling higher output power. After amplification in booster, passing at least part of broadened spectrum, the optical signal spectrum is further broadened by injecting the optical signal into a nonlinear stage to create a SC optical signal.

Abstract: Embodiments relate to a high power supercontinuum (SC) fiber optical source. The SC fiber optical source includes a prebroadening optical fiber that broadens the spectrum of a lower power intermediate optical signal before final amplification. The spectrum broadening creates spectral components which facilitate further spectrum broadening of amplified signal in final nonlinear stage, allowing to achieve flatter and wider spectrum, and reduces nonlinear Stimulated Brillouin Scattering (SBS) that could damage SC fiber optical source components or limit the output power of the SC fiber optical source signal, thus enabling higher output power. After amplification in booster, passing at least part of broadened spectrum, the optical signal spectrum is further broadened by injecting the optical signal into a nonlinear stage to create a SC optical signal.

Abstract: A mirror drive mechanism for a tilting mirror is controlled using feedback from one or more interferometric angular sensors. The wavelength of an optical beam is varied as it is fed into an interferometric angular sensor. The wavelength at which the resulting interference pattern is measured to be at a minimum intensity is determined. This wavelength is used to determine a distance quantity representative of the angular position of the mirror.

Abstract: Attenuation caused by dispersion in an optical fiber communications system is compensated. A number of low-speed channels is to be transmitted across an optical fiber. Each low-speed channel is allocated a different frequency band for transmission. The attenuation caused by dispersion is estimated for each of the frequency bands. The power of each low-speed channel is adjusted to compensate for the estimated attenuation. The power-adjusted low-speed channels are frequency division multiplexed together to produce an electrical high-speed channel suitable for transmission across the communications system.

Abstract: A true time delay beamformer for RF/microwave phased array antenna systems using multiple laser sources, optical modulators to convert the electrical signal to a modulated optical signal, standard optical fiber for creating time delays, dispersive optical fiber for creating delays, optical splitting and/or switching section, photodetectors to convert the modulated optical signal to an electrical signal, and a signal combining section. The true time delay beamformer has the capability to create multiple simultaneous RF/microwave antenna beams. One (more lasers) is used to source one (or more) wavelengths of light to the optical modulator. The signal from one (or more) antenna elements drive the optical modulator. The light from the optical modulator passes through the standard optical fibers and/or the dispersive optical fibers to create time delay variation for one optical modulator relative to another allowing for the formation of RF/microwave beams.

Abstract: A transmitter subsystem generates an optical signal which contains multiple subbands of information. The subbands have different polarizations. For example, in one approach, two or more optical transmitters generate optical signals which have different polarizations. An optical combiner optically combines the optical signals into a composite optical signal for transmission across an optical fiber. In another aspect, each optical transmitter generates an optical signal containing both a lower optical sideband and an upper optical sideband (i.e., a double sideband optical signal). An optical filter selects the upper optical sideband of one optical signal and the lower optical sideband of another optical signal to produce a composite optical signal.

Abstract: Attenuation caused by dispersion in an optical fiber communications system is compensated. A number of low-speed channels is to be transmitted across an optical fiber. Each low-speed channel is allocated a different frequency band for transmission. The attenuation caused by dispersion is estimated for each of the frequency bands. The power of each low-speed channel is adjusted to compensate for the estimated attenuation. The power-adjusted low-speed channels are frequency division multiplexed together to produce an electrical high-speed channel suitable for transmission across the communications system.

Abstract: A transmitter subsystem generates an optical signal which contains multiple subbands of information. The subbands have different polarization. For example, in one approach, two or more optical transmitters generate optical signals which have different polarization. An optical combiner optically combines the optical signals into a composite optical signal for transmission across an optical fiber. In another aspect, each optical transmitter generates an optical signal containing both a lower optical sideband and an upper optical sideband (i.e., a double sideband optical signal). An optical filter selects the upper optical sideband of one optical signal and the lower optical sideband of another optical signal to produce a composite optical signal.

Abstract: A frequency division multiplexing (FDM) node used in optical communications networks provides add-drop multiplexing (ADM) functionality between optical high-speed channels and electrical low-speed channels. The FDM node includes a high-speed system and an ADM crosspoint. The high-speed system converts between an optical high-speed channel and its constituent electrical low-speed channels through the use of frequency division multiplexing and preferably also QAM modulation. The ADM crosspoint couples incoming low-speed channels to outgoing low-speed channels, thus implementing the ADM functionality for the FDM node.

Abstract: A frequency division multiplexing (FDM) node used in optical communications networks provides add-drop multiplexing (ADM) functionality between optical high-speed channels and electrical low-speed channels. The FDM node includes a high-speed system and an ADM crosspoint. The high-speed system converts between an optical high-speed channel and its constituent electrical low-speed channels through the use of frequency division multiplexing and preferably also QAM modulation. The ADM crosspoint couples incoming low-speed channels to outgoing low-speed channels, thus implementing the ADM functionality for the FDM node.