Patent application number | Description | Published |
20110110621 | NOVEL SENSOR ARRAY CONFIGURATION FOR EXTENDING USEFUL SENSING LENGTH OF A SWEPT-WAVELENGTH INTERFEROMETRY BASED SYSTEM - An apparatus for estimating a parameter at distributed locations, the apparatus including: an optical fiber having: a first series of fiber Bragg gratings (FBGs) and configured to measure the parameter at a portion of the distributed locations; a second series of FBGs and configured to measure the parameter at another portion of the distributed locations; and an optical interrogator configured to illuminate the optical fiber and to receive light signals resulting from the illumination, the light signals including first light signals from the first series of FBGs within a first range of wavelengths, second light signals from the second series of FBGs within a second range of wavelengths, and other light signals within a third range of wavelengths, the ranges of wavelengths being distinct from each other; wherein the first light signals and the second light signals are used to estimate the parameter at the distributed locations. | 05-12-2011 |
20110181871 | COMBINED SWEPT-CARRIER AND SWEPT-MODULATION FREQUENCY OPTICAL FREQUENCY DOMAIN REFLECTOMETRY - An apparatus for estimating a parameter, the apparatus includes: an optical fiber; a component in communication with the optical fiber and configured to interact with light at a wavelength related to the parameter; and an optical interrogator in communication with the optical fiber and configured to: illuminate the optical fiber with a series of light inputs, each light input in the series having a substantially constant unique optical wavelength and swept-frequency amplitude modulation; and receive a resulting light signal associated with each light input in the series; wherein the resulting light signals associated with the series of light inputs are used to estimate the parameter. | 07-28-2011 |
20110199618 | Systems and Methods for Optically Generated Trigger Multiplication - Systems and methods for providing trigger signals in an optical interrogator, wherein multiple triggers are generated within each period of a varying reference signal, and wherein the triggers are evenly spaced according to the wavenumber of the reference signal. In one embodiment, an optical frequency domain reflectometry system provides a laser beam to a reference interferometer to produce a reference signal. This signal is passed through a 4×4 optical coupler which splits the signal into a first signal and a second signal that is 90 degrees out of phase with the first signal. These signals are converted to electrical signals, and a trigger unit generates triggers at points at which the two electrical signals have zero-crossings, and at which the magnitudes of the signals are equal. The resulting triggers remain evenly spaced within the period of the reference signals, even when the period is changed. | 08-18-2011 |
20110261361 | System and Method for Effective Isolation of an Interferometer - An interferometer has its performance enhanced by being suspended in a housing that is optionally evacuated. The frame that supports the interferometer is secured to a cover for the housing with a plurality of studs having mechanical vibration isolators. The frame comprises a support flange with a foam layer beneath the interferometer. An optics tray is disposed above the interferometer and holds the assembly to the support flange. The fibers that are connected to the interferometer enter the side of the housing and the entry is sealed off to allow the interior of the housing to be evacuated. | 10-27-2011 |
20120154168 | PHOTONIC CRYSTAL WAVEGUIDE DOWNHOLE COMMUNICATION SYSTEM AND METHOD - A downhole component includes a body portion and a photonic crystal waveguide coupled to the body portion that is configured to receive a signal from a device. | 06-21-2012 |
20120175512 | RAYLEIGH SCATTER-BASED LARGE DIAMETER WAVEGUIDE SENSOR SYSTEM - Disclosed is an apparatus for estimating a parameter in a borehole penetrating the earth. The apparatus includes a large diameter waveguide (LDW) sensor configured to be disposed in the borehole and to sense the parameter at one or more locations along the LDW sensor, the LDW sensor having an outer dimension greater than or equal to 0.25 mm and random variations of an optical property. An optical interrogator is coupled to the LDW sensor and configured to illuminate the LDW sensor with incident light at a swept frequency and to receive light from the large diameter waveguide due to Rayleigh scattering of the incident light by the random variations of the optical property along a length of the LDW sensor. The received light provides information for estimating the parameter and a location along the LDW sensor where the parameter was sensed. | 07-12-2012 |
20120176250 | SYSTEM AND METHOD FOR INTEGRATED DOWNHOLE SENSING AND OPTICAL FIBER MONITORING - A system for measuring downhole parameters is disclosed. The system includes: a carrier configured to be disposed in a borehole in an earth formation; at least one optical fiber sensor in operable communication with the carrier; a measurement assembly including an electromagnetic signal source configured to transmit a first interrogation signal into the optical fiber sensor and a detector configured to receive a reflected signal indicative of a downhole parameter in response to the interrogation signal; and a processor configured to automatically receive scattered signals from the optical fiber sensor, generate distributed scattering data indicative of a condition of the optical fiber sensor and analyze changes in the distributed scattering data to identify changes in the condition of the optical fiber sensor. | 07-12-2012 |
20120179378 | METHOD AND APPARATUS FOR MONITORING VIBRATION USING FIBER OPTIC SENSORS - A apparatus for monitoring a downhole component is disclosed. The apparatus includes: an optical fiber sensor including a plurality of sensing locations distributed along a length of the optical fiber sensor; an interrogation assembly configured to transmit an electromagnetic interrogation signal into the optical fiber sensor and receive reflected signals from each of the plurality of sensing locations; and a processing unit configured to receive the reflected signals, select a measurement location along the optical fiber sensor, select a first reflected signal associated with a first sensing location in the optical fiber sensor, the first sensing location corresponding with the measurement location, select a second reflected signal associated with a second sensing location in the optical fiber sensor, estimate a phase difference between the first signal and the second signal, and estimate a parameter of the downhole component at the measurement location based on the phase difference. | 07-12-2012 |
20120237205 | SYSTEM AND METHOD TO COMPENSATE FOR ARBITRARY OPTICAL FIBER LEAD-INS IN AN OPTICAL FREQUENCY DOMAIN REFLECTOMETRY SYSTEM - A method for estimating a parameter includes: generating an optical signal, the optical signal modulated via a modulation signal having a variable modulation frequency over a period of time; transmitting the modulated optical signal from a light source into an optical fiber, the optical fiber including at least one sensing location configured to reflect light; receiving a reflected signal including light reflected from the at least one sensing location; and demodulating the reflected signal with a reference signal, the reference signal including a time delay relative to the modulation signal based on a distance between the light source and the at least one sensing location. | 09-20-2012 |
20130094798 | Monitoring Structural Shape or Deformations with Helical-Core Optical Fiber - A method, apparatus and system for determine a parameter of a structure is disclosed. A fiber optic cable is coupled to a member. The fiber optic cable includes at least a first core helically arranged in the fiber optic cable that includes at least a first sensor and a second sensor. A first measurement related to the parameter is obtained at the first sensor, and a second measurement at the second sensor related to the parameter is obtained at the second sensor. A difference between the first and second measurements is used to determine the parameter. | 04-18-2013 |
20150083904 | OPTICAL CABLE, DOWNHOLE SYSTEM HAVING OPTICAL CABLE, AND METHOD THEREOF - An optical cable includes an outer tubing. At least one optical fiber disposed within the outer tubing. A stiffening member configured to bend with bending of the outer tubing; wherein the stiffening member shifts a neutral plane of the cable away from the at least one optical fiber. Also included is a method of increasing a bending sensitivity in an optical cable. | 03-26-2015 |