Abstract: Access by decentralized client computers to private information pertaining to a subject stored in a decentralized database is selectively controlled to facilitate an access-control transaction. The private information is embedded with one or more access-control objects containing an independently-verifiable digital representation of consent by the subject and associated computer instructions to control access to the private information based on consent of the subject. The one or more access-control objects are used to determine whether to selectively authorize access to the private information and then embed with the private information a digital representation of the access-control transaction traceable to the consent of the subject.

Abstract: Decentralized database technology is applied to decentralized artificial intelligence (AI) information enabling collaborative AI techniques to enhance the performance of AI models and gain new insights with larger and/or better curated data sets. AI information from multiple independent sources is linked together and synthesized to render the AI information searchable, discoverable, accessible, and traceable, while also ensuring that information remains under its source's control over its lifetime, e.g., controlling the conditions under which other entities may access which pieces of AI information at a particular time.

Abstract: A high-speed interrogation system is provided for interferometric sensors, one example of which is an EFPI sensor, that operates based on spectral interference. The system uses a two mode operation that includes a lower speed, accurate absolute measurement mode and a higher speed, relative measurement mode. The system achieves greater overall measurement accuracy and speed than known sensor interrogation approaches.

Abstract: An optical frequency domain reflectometry (OFDR) measurement is produced from an OFDR apparatus that includes a tunable laser source coupled to a sensing interferometer and a monitor interferometer. The sensing interferometer is also coupled to a waveguide, e.g., an optical sensing fiber. Sensor interferometric data obtained by the OFDR measurement is processed in the spectral domain (e.g., frequency) with one or more parameters to compensate for the optical dispersion associated with the sensing interferometer data. A Fourier Transform of the dispersion-compensated sensing interferometric data in the spectral domain is performed to provide a dispersion-compensated OFDR measurement information in the temporal (e.g., time) domain.

Abstract: A high-speed interrogation system is provided for interferometric sensors, one example of which is an EFPI sensor, that operates based on spectral interference. The system uses a two mode operation that includes a lower speed, accurate absolute measurement mode and a higher speed, relative measurement mode. The system achieves greater overall measurement accuracy and speed than known sensor interrogation approaches.

Abstract: An optical fiber includes primary optical core(s) having a first set of properties and secondary optical core(s) having a second set of properties. The primary set of properties includes a first temperature response, and the secondary set of properties includes a second temperature response sufficiently different from the first temperature response to allow a sensing apparatus when coupled to the optical fiber to distinguish between temperature and strain on the optical fiber. A method and apparatus interrogate an optical fiber having one or more primary optical cores with a first temperature response and one or more secondary optical cores with a second temperature response. Interferometric measurement data associated with each primary and secondary optical core are detected when the optical fiber is placed into a sensing position.

Abstract: Systems and methods for determining the shape and/or position of an object are described. A fiber optic shape sensor (FOSS) may be used in combination with one or more inertial measurement units (IMUs) to mutually cross-correct for errors in the sensors' measurements of position and/or orientation. The IMU(s) may be attached to the FOSS's optical fiber, such that each IMU measures the orientation of a corresponding portion of the optical fiber. The position and shape of the optical fiber can then be determined based on the measurements obtained from the IMU(s) and the measurements obtained from the FOSS. For example, the FOSS measurements and the IMU measurements can be provided to a state estimation unit (e.g., a Kalman filter), which can estimate the position and/or shape of the optical fiber based on those measurements. In some embodiments, the estimates of position are used for navigation of tethered mobile devices.

Abstract: An optical sensing fiber includes multiple reference reflectors spaced along a length of the fiber. Each of the multiple reference reflectors producing a reference scattering event having a known scattering profile including an elevated amplitude relative to scattering detected for neighboring segments of the optical fiber. Each of the segments is a length of contiguous fiber that is useable to initialize and perform a distributed Optical Frequency Domain Reflectometry (OFDR) sensing operation. An OFDR interrogation system is disclosed that measures a parameter using the optical sensing fiber.

Abstract: A high-speed interrogation system is provided for interferometric sensors, one example of which is an EFPI sensor, that operates based on spectral interference. The system uses a two mode operation that includes a lower speed, accurate absolute measurement mode and a higher speed, relative measurement mode. The system achieves greater overall measurement accuracy and speed than known sensor interrogation approaches.

Abstract: An optical fiber includes primary optical core(s) having a first set of properties and secondary optical core(s) having a second set of properties. The primary set of properties includes a first temperature response, and the secondary set of properties includes a second temperature response sufficiently different from the first temperature response to allow a sensing apparatus when coupled to the optical fiber to distinguish between temperature and strain on the optical fiber. A method and apparatus interrogate an optical fiber having one or more primary optical cores with a first temperature response and one or more secondary optical cores with a second temperature response. Interferometric measurement data associated with each primary and secondary optical core are detected when the optical fiber is placed into a sensing position.

Abstract: An optical frequency domain reflectometry (OFDR) measurement is produced from an OFDR apparatus that includes a tunable laser source coupled to a sensing interferometer and a monitor interferometer. The sensing interferometer is also coupled to a waveguide, e.g., an optical sensing fiber. Sensor interferometric data obtained by the OFDR measurement is processed in the spectral domain (e.g., frequency) with one or more parameters to compensate for the optical dispersion associated with the sensing interferometer data. A Fourier Transform of the dispersion-compensated sensing interferometric data in the spectral domain is performed to provide a dispersion-compensated OFDR measurement information in the temporal (e.g., time) domain.

Abstract: An optical frequency domain reflectometry (OFDR) measurement is produced from an OFDR apparatus that includes a tunable laser source coupled to a sensing interferometer and a monitor interferometer. The sensing interferometer is also coupled to a waveguide, e.g., an optical sensing fiber. Sensor interferometric data obtained by the OFDR measurement is processed in the spectral domain (e.g., frequency) with one or more parameters to compensate for the optical dispersion associated with the sensing interferometer data. A Fourier Transform of the dispersion-compensated sensing interferometric data in the spectral domain is performed to provide a dispersion-compensated OFDR measurement information in the temporal (e.g., time) domain.

Abstract: An optical sensing fiber includes multiple reference reflectors spaced along a length of the fiber. Each of the multiple reference reflectors producing a reference scattering event having a known scattering profile including an elevated amplitude relative to scattering detected for neighboring segments of the optical fiber. Each of the segments is a length of contiguous fiber that is useable to initialize and perform a distributed Optical Frequency Domain Reflectometry (OFDR) sensing operation. An OFDR interrogation system is disclosed that measures a parameter using the optical sensing fiber.

Abstract: A high-speed interrogation system is provided for interferometric sensors, one example of which is an EFPI sensor, that operates based on spectral interference. The system uses a two mode operation that includes a lower speed, accurate absolute measurement mode and a higher speed, relative measurement mode. The system achieves greater overall measurement accuracy and speed than known sensor interrogation approaches.

Abstract: Optical frequency domain reflectometry (OFDR) circuitry to perform tasks on an optical fiber to generate calibration or correction data for calibrating or correcting a reference OFDR data set. A segmented technique is used which permits precise and accurate determination of the correction data for even initial and long fiber lengths. Correction information for each segment is stitched together to generate the correction data for the fiber.

Abstract: Systems and methods for determining the shape and/or position of an object are described. A fiber optic shape sensor (FOSS) may be used in combination with one or more inertial measurement units (IMUs) to mutually cross-correct for errors in the sensors' measurements of position and/or orientation. The IMU(s) may be attached to the FOSS's optical fiber, such that each IMU measures the orientation of a corresponding portion of the optical fiber. The position and shape of the optical fiber can then be determined based on the measurements obtained from the IMU(s) and the measurements obtained from the FOSS. For example, the FOSS measurements and the IMU measurements can be provided to a state estimation unit (e.g., a Kalman filter), which can estimate the position and/or shape of the optical fiber based on those measurements. In some embodiments, the estimates of position are used for navigation of tethered mobile devices.

Abstract: Optical frequency domain reflectometry (OFDR) circuitry to perform tasks on an optical fiber to generate calibration or correction data for calibrating or correcting a reference OFDR data set. A segmented technique is used which permits precise and accurate determination of the correction data for even initial and long fiber lengths. Correction information for each segment is stitched together to generate the correction data for the fiber.

Abstract: An optical frequency domain reflectometry (OFDR) measurement is produced from an OFDR apparatus that includes a tunable laser source coupled to a sensing interferometer and a monitor interferometer. The sensing interferometer is also coupled to a waveguide, e.g., an optical sensing fiber. Sensor interferometric data obtained by the OFDR measurement is processed in the spectral domain (e.g., frequency) with one or more parameters to compensate for the optical dispersion associated with the sensing interferometer data. A Fourier Transform of the dispersion-compensated sensing interferometric data in the spectral domain is performed to provide a dispersion-compensated OFDR measurement information in the temporal (e.g., time) domain.

Abstract: A multi-function optical tool may be used for example for built-in fault detection and transceiver source characterization in local optical communication networks. A single device provides swept-heterodyne optical spectrum analysis (SHOSA) and optical frequency-domain reflectometry (OFDR) in an efficient, low-cost package by utilizing a common interrogation laser source, common optical components, and common, low-bandwidth acquisition hardware. The technology provides significant cost, space, and labor savings for network maintainers and technicians.

Abstract: A multi-function optical tool may be used for example for built-in fault detection and transceiver source characterization in local optical communication networks. A single device provides swept-heterodyne optical spectrum analysis (SHOSA) and optical frequency-domain reflectometry (OFDR) in an efficient, low-cost package by utilizing a common interrogation laser source, common optical components, and common, low-bandwidth acquisition hardware. The technology provides significant cost, space, and labor savings for network maintainers and technicians.