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公开(公告)号:US20170082465A1
公开(公告)日:2017-03-23
申请号:US15277347
申请日:2016-09-27
Applicant: Silixa Ltd.
Inventor: Mahmoud Farhadiroushan , Tom Richard Parker , Sergey Shatalin
CPC classification number: G01H9/004 , E21B47/0002 , E21B47/101 , G01D5/35303 , G01D5/35306 , G01D5/35325 , G01D5/35335 , G01D5/35358 , G01D5/35364 , G01D5/35377 , G01D5/35383 , G01F1/66 , G01F1/661 , G01M11/331 , G01V1/40
Abstract: An interferometer apparatus for an optical fibre system and method of use is described. The interferometer comprises an optical coupler and optical fibres which define first and second optical paths. Light propagating in the first and second optical paths is reflected back to the optical coupler to generate an interference signal. First, second and third interference signal components are directed towards respective first, second and third photodetectors. The third photodetector is connected to the coupler via a non-reciprocal optical device and is configured to measure the intensity of the third interference signal component directed back towards the input fibre. Methods of use in applications to monitoring acoustic perturbations and a calibration method are described.
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公开(公告)号:US20150192436A1
公开(公告)日:2015-07-09
申请号:US14662940
申请日:2015-03-19
Applicant: Silixa Ltd.
Inventor: Mahmoud Farhadiroushan , Tom Richard Parker , Sergey Shatalin
CPC classification number: G01H9/004 , E21B47/0002 , E21B47/101 , G01D5/35303 , G01D5/35306 , G01D5/35325 , G01D5/35335 , G01D5/35358 , G01D5/35364 , G01D5/35377 , G01D5/35383 , G01F1/66 , G01F1/661 , G01M11/331 , G01V1/40
Abstract: An interferometer apparatus for an optical fibre system and method of use is described. The interferometer comprises an optical coupler and optical fibres which define first and second optical paths. Light propagating in the first and second optical paths is reflected back to the optical coupler to generate an interference signal. First, second and third interference signal components are directed towards respective first, second and third photodetectors. The third photodetector is connected to the coupler via a non-reciprocal optical device and is configured to measure the intensity of the third interference signal component directed back towards the input fibre. Methods of use in applications to monitoring acoustic perturbations and a calibration method are described.
Abstract translation: 描述了一种用于光纤系统的干涉仪装置及其使用方法。 干涉仪包括光耦合器和限定第一和第二光路的光纤。 在第一和第二光路中传播的光被反射回到光耦合器以产生干涉信号。 首先,第二和第三干扰信号分量指向相应的第一,第二和第三光电探测器。 第三光电检测器通过不可逆的光学装置连接到耦合器,并且被配置成测量指向输入光纤的第三干涉信号分量的强度。 描述了用于监测声学扰动的应用的方法和校准方法。
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公开(公告)号:US20210325238A1
公开(公告)日:2021-10-21
申请号:US17364595
申请日:2021-06-30
Applicant: Silixa Ltd.
Inventor: Mahmoud Farhadiroushan , Tom Richard Parker , Sergey Shatalin
IPC: G01H9/00 , G01D5/353 , E21B47/002 , E21B47/107 , G01M11/00 , G01F1/66 , G01V1/40
Abstract: The present invention provides novel apparatus and methods for fast quantitative measurement of perturbation of optical fields transmitted, reflected and/or scattered along a length of an optical fibre. The present invention can be used for point sensors as well as distributed sensors or the combination of both. In particular this technique can be applied to distributed sensors while extending dramatically the speed and sensitivity to allow the detection of acoustic perturbations anywhere along a length of an optical fibre while achieving fine spatial resolution. The present invention offers unique advantages in a broad range of acoustic sensing and imaging applications. Typical uses are for monitoring oil and gas wells such as for distributed flow metering and/or imaging, seismic imaging, monitoring long cables and pipelines, imaging within large vessel as well as for security applications.
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公开(公告)号:US20210278255A1
公开(公告)日:2021-09-09
申请号:US17328014
申请日:2021-05-24
Applicant: Silixa Ltd. , Chevron U.S.A. Inc.
Inventor: Sergey Shatalin , Julian Dajczgewand , Mahmoud Farhadiroushan , Tom Parker
Abstract: Embodiments of the invention provide an improved optical fiber distributed acoustic sensor system that makes use of an optical fiber having reflector portions distributed along its length in at least a first portion. In particular, in order to increase the spatial resolution of the sensor system to the maximum, the reflector portions are positioned along the fiber separated by a distance that is equivalent to twice the distance an optical pulse travels along the fiber in a single sampling period of the data acquisition opto-electronics within the sensor system. As such, no oversampling of the reflections of the optical pulses from the reflector portions is undertaken, which means that it is important that the sampling points for data acquisition in the sensor system are aligned with the reflections that arrive at the sensor system from along the sensing fiber. In order to ensure such alignment, adaptive delay componentry may be used to adaptively align the reflected optical signals (or their electrical analogues) with the sampling points. Alternatively, control over the sampling points can also be undertaken to re-synchronise the sampling points with the returning reflections. In addition, in order to allow higher speed sampling to be undertaken, reflection equalisation componentry may also be used to reduce the dynamic range of the returning reflections.
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公开(公告)号:US20190323863A1
公开(公告)日:2019-10-24
申请号:US16474747
申请日:2018-01-05
Applicant: Silixa Ltd. , Chevron U.S.A. Inc.
Inventor: Sergey Shatalin , Julian Dajczgewand , Mahmoud Farhadiroushan , Tom Parker
Abstract: An improved optical fiber distributed acoustic sensor system uses an optical fiber having reflector portions distributed along its length in at least a first portion. The reflector portions are positioned along the fiber separated by a distance that is equivalent to twice the distance an optical pulse travels along the fiber in a single sampling period of the data acquisition opto-electronics within the sensor system. No oversampling of the reflections of the optical pulses from the reflector portions is undertaken. The sampling points for data acquisition in the sensor system are aligned with the reflections that arrive at the sensor system from along the sensing fiber. Adaptive delay componentry adaptively aligns the reflected optical signals (or their electrical analogues) with the sampling points. Control over the sampling points can re-synchronise the sampling points with the returning reflections. Reflection equalisation componentry may reduce the dynamic range of the returning reflections.
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公开(公告)号:US10451462B2
公开(公告)日:2019-10-22
申请号:US15962196
申请日:2018-04-25
Applicant: SILIXA LTD. , CHEVRON USA INC.
Inventor: Mahmoud Farhadiroushan , Daniel Finfer , Veronique Mahue , Tom Parker , Sergey Shatalin , Dmitry Strusevich
Abstract: Embodiments of the present invention provide a cable for optical fiber sensing applications formed from fiber wound around a cable core. A protective layer is then preferably placed over the top of the wound fiber, to protect the fiber, and to help keep it in place on the cable core. The cable core is preferably of a diameter to allow bend-insensitive fiber to be wound thereon with low bending losses. The effect of winding the fiber onto the cable core means that the longitudinal sensing resolution of the resulting cable is higher than simple straight fiber, when the cable is used with an optical fiber sensing system such as a DAS or DTS system. The achieved resolution for the resulting cable is a function of the fiber winding diameter and pitch, with a larger diameter and reduced winding pitch giving a higher longitudinal sensing resolution.
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公开(公告)号:US10393573B2
公开(公告)日:2019-08-27
申请号:US15368954
申请日:2016-12-05
Applicant: Silixa Ltd.
Inventor: Mahmoud Farhadiroushan , Tom Richard Parker , Sergey Shatalin
Abstract: The present invention provides novel apparatus and methods for fast quantitative measurement of perturbation of optical fields transmitted, reflected and/or scattered along a length of an optical fiber. The present invention can be used for point sensors as well as distributed sensors or the combination of both. In particular this technique can be applied to distributed sensors while extending dramatically the speed and sensitivity to allow the detection of acoustic perturbations anywhere along a length of an optical fiber while achieving fine spatial resolution. The present invention offers unique advantages in a broad range of acoustic sensing and imaging applications. Typical uses are for monitoring oil and gas wells such as for distributed flow metering and/or imaging, seismic imaging, monitoring long cables and pipelines, imaging within large vessel as well as for security applications.
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公开(公告)号:US20170082484A1
公开(公告)日:2017-03-23
申请号:US15368954
申请日:2016-12-05
Applicant: Silixa Ltd.
Inventor: Mahmoud Farhadiroushan , Tom Richard Parker , Sergey Shatalin
CPC classification number: G01H9/004 , E21B47/0002 , E21B47/101 , G01D5/35303 , G01D5/35306 , G01D5/35325 , G01D5/35335 , G01D5/35358 , G01D5/35364 , G01D5/35377 , G01D5/35383 , G01F1/66 , G01F1/661 , G01M11/331 , G01V1/40
Abstract: The present invention provides novel apparatus and methods for fast quantitative measurement of perturbation of optical fields transmitted, reflected and/or scattered along a length of an optical fibre. The present invention can be used for point sensors as well as distributed sensors or the combination of both. in particular this technique can be applied to distributed sensors while extending dramatically the speed and sensitivity to allow the detection of acoustic perturbations anywhere along a length of an optical fibre while achieving fine spatial resolution. The present invention offers unique advantages in a broad range of acoustic sensing and imaging applications. Typical uses are for monitoring oil and gas wells such as for distributed flow metering and/or imaging, seismic imaging, monitoring long cables and pipelines, imaging within large vessel as well as for security applications.
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公开(公告)号:US20230314189A1
公开(公告)日:2023-10-05
申请号:US18209569
申请日:2023-06-14
Applicant: Silixa Ltd.
Inventor: Mahmoud Farhadiroushan , Tom Parker , Sergey Shatalin
CPC classification number: G01D5/3537 , G01H9/004 , G01D5/35306 , G01D5/35374 , E21B47/135
Abstract: An optical fiber distributed acoustic sensor system makes use of a specially designed optical fiber to improve overall sensitivity of the system by a factor in excess of 10. This is achieved by inserting into the fiber weak broadband reflectors periodically along the fiber. The reflectors reflect a small proportion of the light from the DAS incident thereon back along the fiber, typically in the region of 0.001% to 0.1%. To allow for temperate compensation to ensure that the same reflectivity is obtained if the temperature changes, the reflection bandwidth is relatively broadband. The reflectors are formed from a series of fiber Bragg gratings, each with a different center reflecting frequency, the reflecting frequencies and bandwidths of the gratings being selected to provide the broadband reflection. The reflectors are spaced at the desired spatial resolution of the optical fiber DAS.
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公开(公告)号:US11719560B2
公开(公告)日:2023-08-08
申请号:US16934189
申请日:2020-07-21
Applicant: Silixa Ltd.
Inventor: Mahmoud Farhadiroushan , Tom Parker , Sergey Shatalin
IPC: G01D5/353 , G01H9/00 , E21B47/135 , G01V8/16
CPC classification number: G01D5/3537 , G01D5/35306 , G01D5/35374 , G01H9/004 , E21B47/135 , G01V8/16
Abstract: An optical fiber distributed acoustic sensor system makes use of a specially designed optical fiber to improve overall sensitivity of the system by a factor in excess of 10. This is achieved by inserting into the fiber weak broadband reflectors periodically along the fiber. The reflectors reflect a small proportion of the light from the DAS incident thereon back along the fiber, typically in the region of 0.001% to 0.1%. To allow for temperate compensation to ensure that the same reflectivity is obtained if the temperature changes, the reflection bandwidth is relatively broadband. The reflectors are formed from a series of fiber Bragg gratings, each with a different center reflecting frequency, the reflecting frequencies and bandwidths of the gratings being selected to provide the broadband reflection. The reflectors are spaced at the desired spatial resolution of the optical fiber DAS.
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