CN114593893A - Method for quickly and accurately measuring distance and geographically positioning underground communication optical cable - Google Patents
Method for quickly and accurately measuring distance and geographically positioning underground communication optical cable Download PDFInfo
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- CN114593893A CN114593893A CN202210182898.3A CN202210182898A CN114593893A CN 114593893 A CN114593893 A CN 114593893A CN 202210182898 A CN202210182898 A CN 202210182898A CN 114593893 A CN114593893 A CN 114593893A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
- G01M11/30—Testing of optical devices, constituted by fibre optics or optical waveguides
- G01M11/31—Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter and a light receiver being disposed at the same side of a fibre or waveguide end-face, e.g. reflectometers
- G01M11/3109—Reflectometers detecting the back-scattered light in the time-domain, e.g. OTDR
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H9/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means
- G01H9/004—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means using fibre optic sensors
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/46—Processes or apparatus adapted for installing or repairing optical fibres or optical cables
- G02B6/56—Processes for repairing optical cables
- G02B6/562—Processes for repairing optical cables locatable, e.g. using magnetic means
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Abstract
The invention discloses a method for quickly and accurately measuring distance and geographically positioning an underground communication optical cable, which comprises the following steps of: (1) mounting an optical distance measuring device at a known location; (2) setting a plurality of vibration points on the communication optical cable; (3) vibrating one of the vibration points; (4) measuring the optical accurate length of the vibration point from a monitoring port of the optical distance measuring equipment as a calibration distance by using optical distance measuring equipment, and acquiring the calibration geographical position of the vibration point; (5) circularly executing the step (3) and the step (4) until the calibration distances of all the vibration points are measured and the calibration geographical positions of all the vibration points are collected; 6) measuring the distance from the point to be measured to the monitoring port of the optical distance measuring equipment to be the optical accurate length of the point to be measured; (7) and acquiring the calibration distances of all the vibration points and the calibration geographical positions of all the vibration points to sequentially compare the optical accurate lengths of the points to be measured so as to accurately position the geographical positions of the points to be measured. The invention is fast and accurate.
Description
Technical Field
The invention relates to the technical field of optical cable positioning, in particular to a method for quickly and accurately measuring distance and positioning geography of an underground communication optical cable.
Background
The underground power communication optical cable is an important infrastructure for effectively guaranteeing the safety and stability of power communication, and generally comprises urban pipeline optical cables, transformer substation guide optical cables, distribution network communication optical cables and the like. However, in the urban construction process, some developers do not go through related procedures in order to pursue efficiency and save cost, and directly excavate without knowing the laying condition of underground pipelines, so that the underground electric power communication optical cable is often damaged by external force caused by construction operation, and the electric power communication is seriously influenced. The electric power underground communication optical cable is usually laid in open ditches, direct burial, pipe penetrating and other modes, has the characteristics of wide distribution, invisibility and the like, has higher difficulty in daily management and maintenance work of the underground electric power communication optical cable, can only provide approximate data for the data and GIS data of the conventional production management system in the daily maintenance and rush repair work, and has limited effect. Therefore, under the condition that the production management system and the GIS system lack accurate on-site geographic spatial data and corresponding system display functions, the geographic spatial data condition is not clear for the statistics and distribution positioning of the invisible underground electric power communication optical cables, and the production management system and the GIS system become difficult points and pain points of the operation and maintenance work of the team underground electric power communication optical cables.
At present, in the processes of first-aid repair and daily maintenance, the fault point of the underground optical cable is searched by adopting an ODTR (optical distribution tomography) lighting ranging mode, and due to the fact that relevant data of a plurality of existing optical cables are lost, the ODTR cannot accurately judge and find the geographical position of a specific breakpoint after measuring the distance of the specific breakpoint. Large-scale excavation and section-by-section manual searching are required. The excavation work amount and investment are huge, and a large amount of time is consumed. The problem is always the difficult problem of the current team maintenance, which seriously affects the efficiency of the first-aid repair and daily maintenance work and increases the difficulty of the operation and maintenance work. Even the situation that the whole section of optical cable is idle and can not be used due to the fact that the buried urban underground optical cable has breakpoints and is difficult to excavate and repair due to the fact that accurate geographical positioning cannot be achieved.
Therefore, a method for quickly and accurately measuring and geographically locating a point to be measured on a communication optical cable in the field is needed.
Disclosure of Invention
The invention provides a method for quickly and accurately measuring distance and positioning geography of an underground communication optical cable, which can quickly and accurately measure the distance and position geography of a point to be measured on the communication optical cable on site.
In order to solve the problems, the method for quickly and accurately measuring the distance and positioning the geography of the underground communication optical cable comprises the following steps:
(1) mounting an optical distance measuring device at a known location;
(2) setting a plurality of vibration points on the communication optical cable;
(3) vibrating one of the vibration points;
(4) measuring the optical accurate length of the vibration point from a monitoring port of the optical distance measuring equipment as a calibration distance by using optical distance measuring equipment, and acquiring the calibration geographical position of the vibration point;
(5) circularly executing the step (3) and the step (4) until the calibration distances of all the vibration points are measured and the calibration geographical positions of all the vibration points are collected;
(6) measuring the distance from the point to be measured to the monitoring port of the optical distance measuring equipment to be the optical accurate length of the point to be measured;
(7) and (5) sequentially comparing the optical accurate lengths of the points to be measured by the calibration distances of all the vibration points obtained in the step (5) and collecting the calibrated geographical positions of all the vibration points to accurately position the geographical positions of the points to be measured.
Particularly, in the step (4), the specific method for measuring the optical accurate length from the vibration point to the monitoring port of the optical distance measuring device by the optical distance measuring device is to perform vibration distance measurement by using a distributed optical fiber vibration monitoring device.
Particularly, in the step (6), the specific method for measuring the distance from the point to be measured to the monitoring port of the optical distance measuring device is to use an OTDR lighting ranging method.
In particular, the vibration point is a vibration source for manually striking a trench of the communication cable.
In particular, the vibration point is a cable well capable of generating vibrations.
In particular, the point to be measured is an optical fiber breakpoint or an optical fiber defect point.
In particular, the specific method for collecting the calibration geographical position of the vibration point is to accurately map coordinates and accurately position the vibration point on a map.
Particularly, the geographic position of the point to be measured is displayed on a GIS map.
The beneficial effects of the invention are as follows:
1. the invention utilizes the mode of artificial vibration communication optical cable to measure and calculate the distance and combines OTDR to carry out lighting and measure the distance to be measured so as to compare the distance to be measured, thereby realizing the map fixed-point positioning of the point to be measured of the underground optical cable, utilizes the conventional OTDR equipment to light and measure the distance to be measured, and utilizes the system to judge the general geographic position of the specific breakpoint. Based on the general location, the cables near the well near the range are accurately measured by manual vibration as shown in the following figure. And comparing the optical accurate lengths of the points to be measured in sequence through the accurate distance measurement results of the manual vibration of the multiple points to accurately position the geographic positions of the points to be measured.
2. Because the accurate optical length from the manual knocking vibration point to the monitoring port of the device can be measured and obtained by the distributed optical fiber vibration monitoring device in a manual knocking vibration mode, the accurate map coordinates of the knocking vibration point can be collected and the accurate map coordinates can be accurately positioned on a map when the field vibration knocking occurs. The corresponding relation between the optical accurate length of the vibration point from the monitoring port of the equipment and the accurate position of the vibration point on the map can be established by carrying out artificial vibration measurement on the section of optical cable at a plurality of different places (distances). When the section of optical cable has a fault, the OTDR equipment with the conventional fault processing is used for lighting to measure the optical length of the fault point from the light measurement port, and then the optical length obtained by carrying out artificial vibration on the optical cable in multiple places for multiple times is compared with the optical length obtained by lighting the OTDR equipment with the conventional fault processing one by one, so that the accurate geographical position where the optical length of the fault point measured by lighting the OTDR equipment with the conventional fault processing is located can be quickly found. The system also makes historical records of the distance of the cable from the manual vibration and the geographic position of the point (i.e. the actual length of the distance the cable is lighted at the geographic position point is known). The method is convenient for faster positioning of the optical fiber breakpoint (defect) lighting, measuring and calculating of the distance positioning of the specific geographic position.
3. Vibration ranging of the well and correlation and recording of the well position with the measured optical cable distance length are also more convenient and meaningful due to the simpler and more accurate means of vibration in the well, and can be performed by a combination of vibration in the well. Once the corresponding relation between the optical fiber optical ranging length of each well where the optical cable passes and the specific map geographic position of each well is recorded through the artificial vibration measurement mode. When the optical cable breakpoint is detected through the OTDR, the distance between two wells of the breakpoint can be known through the optical fiber ranging length of each well, the distance between two wells on site is detected through the manual vibration ranging mode, and when the distance is equal to or close to the distance between the breakpoints detected through the OTDR, the place where the optical cable breakpoint is located can be judged. And realizing accurate geographical positioning.
4. According to the invention, the vibration point is accurately measured and calculated in a vibration communication optical cable mode, and the fault point is measured and calculated in combination with the fault point, so that the fault point can be accurately positioned on site, the manual searching of large-scale excavation section by section is avoided, and the searching efficiency and the maintenance speed are effectively improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic diagram of the operation of the embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.
In addition, the descriptions related to "first", "second", etc. in the present invention are only for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
In the present invention, unless otherwise explicitly stated or limited, the terms "connected", "fixed", and the like are to be understood broadly, for example, "fixed" may be fixedly connected, may be detachably connected, or may be integrated; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In addition, the technical solutions in the embodiments of the present invention may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination of technical solutions should not be considered to exist, and is not within the protection scope of the present invention.
As shown in fig. 1, a method for fast and accurate ranging and geographical positioning of an underground optical communication cable according to an embodiment of the present invention.
(1) Installing optical distance measuring equipment on the intelligent operation and maintenance system of the underground power communication optical cable; the optical distance measuring device of the present embodiment is a distributed optical fiber vibration monitoring device.
(2) 3 vibration points are set on the communication optical cable, namely a vibration point 1, a vibration point 2 and a vibration point 3.
(3) Vibrating one of the vibration points;
(4) measuring the optical accurate length of the vibration point from a monitoring port of the optical distance measuring equipment as a calibration distance by using optical distance measuring equipment, and acquiring the calibration geographical position of the vibration point; wherein vibration point 1 is on cable well a, vibration point 2 is on cable well B, and vibration point 3 is on a known geographical location by a vibration source manually striking the trench of the communication cable. The specific method for measuring the optical accurate length from the vibration point to the monitoring port of the optical distance measuring equipment by the optical distance measuring equipment is to adopt distributed optical fiber vibration monitoring equipment to carry out vibration distance measurement. The specific method for collecting the calibration geographical position of the vibration point is to accurately map coordinates and accurately position the vibration point on a map.
(5) Circularly executing the step (3) and the step (4) until the calibration distances of all the vibration points are measured and the calibration geographical positions of all the vibration points are collected;
(6) measuring the distance from the point to be measured to the monitoring port of the optical distance measuring equipment to be the optical accurate length of the point to be measured; the specific method for measuring the distance between the point to be measured and the monitoring port of the optical distance measuring equipment is to adopt an OTDR (optical time Domain reflectometer) lighting ranging method.
(7) And (5) comparing the optical accurate lengths of the points to be measured in sequence by the calibration distances of all the vibration points obtained in the step (5) and collecting the calibration geographical positions of all the vibration points to accurately position the geographical positions of the points to be measured. And displaying the geographic position of the point to be measured on the GIS map.
The embodiment of the invention has the following beneficial effects:
1. the embodiment of the invention utilizes an artificial vibration communication optical cable mode to measure and calculate the distance and combines OTDR to carry out lighting and measure the distance of the point to be measured for comparison so as to realize the map fixed-point positioning of the point to be measured of the underground optical cable, utilizes conventional OTDR equipment to light and measure the distance of the point to be measured, and utilizes the system to judge the general geographic position of a specific breakpoint. Based on the general location, the cables near the well near the range are accurately measured by manual vibration as shown in the following figure. And comparing the optical accurate lengths of the points to be measured in sequence through the accurate distance measurement results of the manual vibration of the multiple points to accurately position the geographic positions of the points to be measured.
2. Because the accurate optical length from the manual knocking vibration point to the monitoring port of the device can be measured and obtained by the distributed optical fiber vibration monitoring device in a manual knocking vibration mode, the accurate map coordinates of the knocking vibration point can be collected and the accurate map coordinates can be accurately positioned on a map when the field vibration knocking occurs. The corresponding relation between the optical accurate length of the vibration point from the monitoring port of the equipment and the accurate position of the vibration point on the map can be established by carrying out artificial vibration measurement on the section of optical cable at a plurality of different places (distances). When the fault of the optical cable occurs, the optical length of the fault point from the light measurement port is measured by lighting the OTDR equipment subjected to conventional fault treatment, and then the optical length of the fault point measured by lighting the OTDR equipment subjected to conventional fault treatment is found by carrying out multiple times of artificial vibration in multiple places of the optical cable, and the optical length of the multiple times of artificial vibration distance measurement is successively compared with the optical length measured by lighting the OTDR equipment subjected to conventional fault treatment, so that the accurate geographical position where the optical length of the fault point measured by lighting the OTDR equipment subjected to conventional fault treatment is located can be quickly found. The system also makes historical records of the distance of the cable from the manual vibration and the geographic position of the point (i.e. the actual length of the distance the cable is lighted at the geographic position point is known). The method is convenient for faster positioning of the optical fiber breakpoint (defect) lighting, measuring and calculating of the distance positioning of the specific geographic position.
3. Vibration ranging of the well and correlation and recording of the well position with the measured optical cable distance length are also more convenient and meaningful due to the simpler and more accurate manner of vibration in the well, and can be performed by a combination of vibration in the well. Once the corresponding relation between the optical fiber optical ranging length of each well where the optical cable passes and the specific map geographic position of each well is recorded through the artificial vibration measurement mode. When the optical cable breakpoint is detected through the OTDR, the distance between two wells of the breakpoint can be known through the optical fiber ranging length of each well, the distance between two wells on site is detected through the manual vibration ranging mode, and when the distance is equal to or close to the distance between the breakpoints detected through the OTDR, the place where the optical cable breakpoint is located can be judged. And realizing accurate geographical positioning.
4. According to the embodiment of the invention, the vibration point is accurately measured and calculated in a vibration communication optical cable mode, and the fault point is measured and calculated in combination with the fault point, so that the fault point can be accurately positioned on site, the manual searching of large-scale excavation section by section is avoided, and the searching efficiency and the maintenance speed are effectively improved.
According to the embodiment of the invention, the polishing distance measurement result of the ODTR is compared with the accurate distance measurement result of the artificial vibration source, so that the position of the specific optical cable breakpoint can be accurately found, and meanwhile, the technology can be applied to the accurate geographic position positioning of the hidden danger of the optical cable, the optical cable searching and other works.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity/action/object from another entity/action/object without necessarily requiring or implying any actual such relationship or order between such entities/actions/objects; the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or system in which the element is included.
The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.
Although the embodiments of the present invention have been described, various changes or modifications may be made by the patentee within the scope of the appended claims, and the scope of the present invention should be determined not to exceed the range described in the claims. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts of the present invention. It should be noted that there are no specific structures but rather a few limitations to the preferred embodiments of the present invention, and that those skilled in the art can make various changes, modifications and alterations without departing from the spirit and scope of the invention; such modifications, variations, combinations, or adaptations of the invention using its spirit and scope, as defined by the claims, may be directed to other uses and embodiments.
Claims (8)
1. A method for quickly and accurately measuring distance and geographically locating an underground communication optical cable is characterized by comprising the following steps: the method comprises the following steps:
(1) mounting an optical distance measuring device at a known location;
(2) setting a plurality of vibration points on the communication optical cable;
(3) vibrating one of the vibration points;
(4) measuring the optical accurate length of the vibration point from a monitoring port of the optical distance measuring equipment as a calibration distance by using optical distance measuring equipment, and acquiring the calibration geographical position of the vibration point;
(5) circularly executing the step (3) and the step (4) until the calibration distances of all the vibration points are measured and the calibration geographical positions of all the vibration points are collected;
(6) measuring the distance between the point to be measured and the monitoring port of the optical distance measuring equipment to be the optical accurate length of the point to be measured;
(7) and (5) sequentially comparing the optical accurate lengths of the points to be measured by the calibration distances of all the vibration points obtained in the step (5) and collecting the calibrated geographical positions of all the vibration points to accurately position the geographical positions of the points to be measured.
2. The method of claim 1, wherein the method comprises the steps of: in the step (4), the specific method for measuring the optical accurate length from the vibration point to the monitoring port of the optical distance measuring equipment by the optical distance measuring equipment is to use distributed optical fiber vibration monitoring equipment to carry out vibration distance measurement.
3. The method of claim 1, wherein the method comprises the steps of: in the step (6), the specific method for measuring the distance from the point to be measured to the monitoring port of the optical distance measuring device is to use an OTDR lighting ranging method.
4. The method of claim 1, wherein the method comprises the steps of: the vibration point is a vibration source for manually beating a pipe channel of the communication optical cable.
5. The method of claim 1, wherein the method comprises the steps of: the vibration point is a cable well capable of generating vibration.
6. The method of claim 1, wherein the method comprises the steps of: the point to be measured is an optical fiber breakpoint or an optical fiber defect point.
7. The method of claim 1, wherein the method comprises the steps of: the specific method for collecting the calibration geographical position of the vibration point is to accurately map coordinates and accurately position the vibration point on a map.
8. The method for rapid and accurate ranging and geolocation of underground communications cables according to claim 1, characterized in that: and displaying the geographic position of the point to be measured on a GIS map.
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| CN202210182898.3A CN114593893A (en) | 2022-02-27 | 2022-02-27 | Method for quickly and accurately measuring distance and geographically positioning underground communication optical cable |
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| CN202210182898.3A CN114593893A (en) | 2022-02-27 | 2022-02-27 | Method for quickly and accurately measuring distance and geographically positioning underground communication optical cable |
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