CN100558013C - A kind of monitoring device of fiber optic network and method - Google Patents
A kind of monitoring device of fiber optic network and method Download PDFInfo
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- CN100558013C CN100558013C CNB2005100678788A CN200510067878A CN100558013C CN 100558013 C CN100558013 C CN 100558013C CN B2005100678788 A CNB2005100678788 A CN B2005100678788A CN 200510067878 A CN200510067878 A CN 200510067878A CN 100558013 C CN100558013 C CN 100558013C
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Abstract
The present invention relates to a kind of monitoring device and method of fiber optic network, each branch's light path front end setting at fiber optic network can be filtered the optical filter of different corresponding wavelength, and import successively in each branch's light path by the light signal of the corresponding wavelength that each is different, analyze the light signal that each branch's light path is reflected then, the individual states of each the branch's light path on the fiber optic network with branch's light path can be differentiated, be used to solve when carrying out the optical fiber quality monitoring on the fiber optic network problem of multiple-limb light path phase mutual interference.
Description
Technical field
The present invention relates to a kind of fiber optic network, particularly a kind of monitoring device and method of fiber optic network of the individual states of judging branch's light path.
Background technology
Present EPON (Passive Optical Network, a PON) the most popular technology in the optical access network (OpticalAccess Network) beyond doubt, but, still can't break through for the monitoring technique of optical fiber quality.Directly use traditional optical time domain reflectometer (Optical Time-Domain Reflectometry at present, OTDR, be convenient expression, below represent) with abbreviation, can cause the problem that is difficult to differentiate between indivedual branches light paths (Branch), especially differentiate in branch's light path of close length, be subject to the influence of OTDR blind area (DeadZone), still can't solve at present.This is because the light pulse that OTDR was used for monitoring can enter in the optic fibre light path of each branch, same, light wave by each light path institute reflected back also will be received by optical time domain reflectometer simultaneously, so different branches light path but all can contribute to some extent to the optical receiver of OTDR apart from the reverberation of OTDR same distance, and then be superimposed upon on the track (Trace) of OTDR, causing wherein, one road optical fiber has incident (Event) to take place, especially when two optical path lengths were close, using the traditional monitoring technology can't tell this incident was to betide on which branch's light path.
Please refer to shown in Figure 1, a kind of fiber optic network framework with multiple-limb light path similar to EPON, wherein locate to use the optical splitter 10 of a 1:2 for 3.07 kilometers at the distance head end, and re-use a 1:8 optical splitter 20 apart from 2.08 kilometers places of this optical splitter, output a to d connects branch's light path of 0.42,1.54,1.67 and 2.45 kilometer respectively, and output e to h does not then connect.Front end at this network uses a traditional OTDR to measure the optical fiber state of this network, as shown in Figure 2, show that OTDR measures the path profile of being exported, path 2 presents the loss of 1:2 optical splitter 10,4 losses that present 1:8 optical splitter 20 in path, the tail end of output a to d light path also are presented on respectively on the path 5,6,7 and 8 of OTDR track.Can see all branched optical cable line states all is superimposed upon on the same path profile, though situations all on the fiber optic network all can show, if but generation problem on branch's light path therein, can only compare by track traditionally with original no problem, cause that track changes after this position because name a person for a particular job, and this change will terminate in branch's light path terminal point of generation problem in situation.Present for the optical fiber status monitoring of branch's light path traditionally for utilizing the method, as U.S. Patent number 5187362.
But, on the close light path of these two length, OTDR track as path 6 and 7 these two places, blind spots limit influence because of OTDR, distinguish that both slightly have any problem, if optical path length increases and must use the more OTDR input of long pulse, the blind area will increase, and then can't tell 1.54 and 1.67 kilometers two light paths.When one of them the generation incident in this two light path, using conventional method to monitor the incident of can't distinguishing is to occur on which light path.In addition, use traditional approach to monitor, show on the same OTDR track, so still can't measure the characteristic of optical fiber on indivedual light paths because the reverberation of all light paths will superpose, as loss etc., therefore need the new monitoring technology of exploitation to differentiate and the problem of distinguishing ability to solve.
Summary of the invention
The invention provides a kind of monitoring device and method of fiber optic network, can break through the characteristic of traditional optical time domain reflectometer and restriction physically, can use at fiber optic network with branch's light path, be used for distinguishing the optical fiber state of indivedual branches light path, to solve the existing in prior technology problem substantially.
To achieve these goals, the invention provides a kind of monitoring device of fiber optic network, be applied to have on the fiber optic network of optical fiber of a plurality of branches light path, described fiber optic network has the optical network terminal that comprises optical line terminal and a plurality of Optical Network Terminal, and optical line terminal is connected respectively to each Optical Network Terminal by the optical fiber with a plurality of branches light path, the monitoring device of fiber optic network includes a plurality of optical filters and an adjustable optical time-domain reflectomer (Tunable OTDR), these optical filters are arranged at aforementioned branches light path front end respectively, and each optical filter can filter the light signal of different corresponding wavelength, the adjustable optical time-domain reflectomer then is connected in before the crosspoint of branch's light path of optical fiber, has the light signal of each corresponding optical filter wavelength to each branch's light path in order to export successively, and the light signal that reflected of each branch's light path that receives each batch, for analyzing each batch light signal and judging the situation of each branch's light path, when judging not have damage corresponding to the luminous power curve of the reflected light signal of one of them described corresponding wavelength, and the luminous power curve of the reflected light signal of all the other described corresponding wavelength judges that damage is arranged, and judges then that branch's light path corresponding to the optical filter of one of them described corresponding wavelength diminishes to ruin.
The monitoring device of described fiber optic network also comprises an optical splitter, is arranged on before the described branch light path, in order to described branch light path is imported in described light signal beam split.
The monitoring device of described fiber optic network also comprises a light receiving unit and an optical transmission unit, is arranged at described optical network terminal, respectively in order to receive and to transmit described light signal.
The monitoring device of described fiber optic network also includes a planar optical waveguide, is arranged on before the described branch light path, in order to handle the light signal that described light receiving unit and described optical transmission unit receive and transmit.
The monitoring device of described fiber optic network also comprises an optical coupler, in order to described optical line terminal and described adjustable optical time-domain reflectomer are connected in described optical fiber.
Described optical coupler is that coupler is used in a wavelength-division more.
Described adjustable optical time-domain reflectomer inside is provided with an adjustable laser light source.
In addition, the present invention also provides a kind of monitoring method of fiber optic network, be applied to have on the fiber optic network of optical fiber of a plurality of branches light path, described fiber optic network has the optical network terminal that comprises optical line terminal and a plurality of Optical Network Terminal, and optical line terminal is connected respectively to each Optical Network Terminal by the optical fiber with a plurality of branches light path, the method includes the following step: an optical filter is set in each aforementioned each branch's light path front end, these optical filters can filter the light signal of different corresponding wavelength respectively, the adjustable optical time-domain reflectomer import successively have each corresponding wavelength light signal to each branch's light path, and make each light signal be subjected to different optical filter filtrations respectively, then, the adjustable optical time-domain reflectomer receives the light signal that the light signal of different corresponding wavelength is reflected by each branch's light path in regular turn, then, analyze the light signal of aforementioned reflection, judge the situation of each described branch light path, when judging not have damage corresponding to the luminous power curve of the reflected light signal of one of them described corresponding wavelength, and the luminous power curve of the reflected light signal of all the other described corresponding wavelength judges that damage is arranged, and judges then that branch's light path corresponding to the optical filter of one of them described corresponding wavelength diminishes to ruin.
The monitoring method of described fiber optic network also comprises:
The step of monitoring for a plurality of EPONs is utilized computer control light changeover module to automatically switch and is monitored the path simultaneously, and monitors the optical fiber situation of fiber optic network by the adjustable optical time-domain reflectomer.
Describe the present invention below in conjunction with the drawings and specific embodiments, but not as a limitation of the invention.
Description of drawings
Fig. 1 is the fiber optic network Organization Chart with multiple-limb of prior art;
Fig. 2 measures the path profile of being exported for the OTDR of prior art;
Fig. 3 is the schematic diagram of monitoring device of the fiber optic network of first embodiment of the invention;
Fig. 4 A is the luminous power curve chart that the optical time domain reflectometer of the first embodiment of the present invention under normal condition measured the light signal that is received;
Fig. 4 B is the luminous power curve chart that the optical time domain reflectometer of the first embodiment of the present invention when incident takes place measured the light signal received, and wherein the wavelength of the light signal of exporting with adjustable optical filter adjustment optical time domain reflectometer is the corresponding wavelength of respective path A, C, D;
Fig. 4 C is the luminous power curve chart that the optical time domain reflectometer of the first embodiment of the present invention when incident takes place measures the light signal received, and wherein the wavelength of the light signal of exporting with adjustable optical filter adjustment optical time domain reflectometer is the corresponding wavelength of respective path B;
Fig. 5 is the schematic diagram of monitoring device of the fiber optic network of the second embodiment of the present invention; And
Fig. 6 is the schematic diagram of the monitoring device of the fiber optic network that the third embodiment of the present invention provided.
Wherein, Reference numeral is as follows:
2～8,21～26 paths
10,20 optical splitters
A～h output
30,40,60,70 fiber optic networks
31,45 optical fiber
32,46,64,71 branch's light paths
33,41 optical line terminals
34,42 Optical Network Terminal
35,51 optical filters
36,50,62 adjustable optical time-domain reflectomers
37,49 optical splitters
38 adjustable optical filters
39 optical time domain reflectometers
43 light receiving units
44 optical transmission units
47 planar optical waveguides
48 couplers
61 computers
63 smooth changeover modules
Embodiment
The monitoring method of fiber optic network provided by the present invention, be mainly used on the fiber optic network of optical fiber with a plurality of branches light path, as EPON, this fiber optic network can have the optical network terminal that includes optical line terminal (OLT) and a plurality of Optical Network Terminal (ONT), and optical line terminal is connected respectively to each Optical Network Terminal by the optical fiber with a plurality of branches light path, be arranged on each branch's light path front end of fiber optic network by the optical filter that can filter different corresponding wavelength, and utilize successively that input has the light signal of each corresponding wavelength in each branch's light path, making each light signal be subjected to different optical filters respectively filters, the light signal that in regular turn each branch's light path is reflected again receives, then, analyze the light signal of these reflections, can judge the situation of each branch's light path on the optical fiber.
Then, see also Fig. 3, the monitoring device of the disclosed a kind of fiber optic network of one embodiment of the invention, it is applied in the fiber optic network 30 of the optical fiber 31 with a plurality of branches light path 32, this fiber optic network 30 has the optical network terminal that includes optical line terminal 33 (OLT) and a plurality of Optical Network Terminal (ONT) 34, and optical line terminal 33 is connected respectively to each Optical Network Terminal 34 by the optical fiber 31 with a plurality of branches light path 32, the monitoring device of fiber optic network comprises a plurality of optical filters 35 and adjustable optical time-domain reflectomer 36 (Tunable OTDR), each optical filter 35 can filter the light signal of different corresponding wavelength respectively, at this, one optical splitter 37 can be arranged on before each branch's light path 32, in order to the light signal beam split is imported in each branch's light path 32, optical filter 35 then is separately positioned on after the optical splitter 37, be each branch's light path 32 front end of fiber optic network 30,36 of adjustable optical time-domain reflectomers are connected before the crosspoint of each branch's light path 32 of optical fiber 31, has the light signal of each corresponding wavelength in each branch's light path 32 in order to export successively, and the light signal that reflected of the aforementioned branches light path 32 that receives each batch, with the situation that is used to analyze each batch light signal and judges each branch's light path.And this adjustable optical time-domain reflectomer 36 can be realized by the inner adjustable laser light source that uses of optical time domain reflectometer, or can form by adjustable optical filter (TunableOptical Filter) 38 and optical time domain reflectometer (OTDR) 39, adjustable optical filter 38 is installed in the output of optical time domain reflectometer 39, adjust the wavelength of output light signal by adjustable optical filter 38, make the wavelength of the light signal that last optical time domain reflectometer 39 exported meet aforementioned lights filter 35 filtrable corresponding wavelength, the light signal that makes the optical filter 35 that meets corresponding wavelength stop optical time domain reflectometers 39 to be exported passes through.
In the monitoring device of fiber optic network of the present invention, before different branches light path 32, add the optical filter 35 that can filter different corresponding wavelength, and each optical filter 35 filtrable wave bands are in the wave band of the light signal that meets optical time domain reflectometer 39 outputs.Because the light signal that optical time domain reflectometer 39 is exported is a wide spectrum light source, present embodiment can use narrower adjustable optical filter 38 and a plurality of optical filter 35 to be applied in the monitoring device of this fiber optic network, adjust adjustable optical filter 38, make the wavelength of the light signal that optical time domain reflectometer 39 exported, the optical filter 35 filtrable corresponding wavelength of corresponding indivedual branches light path 32, then can make the light signal of optical time domain reflectometer 39 can't be by adding branch's light path 32 of this corresponding wavelength optical filter 35, but other 32 of branch's light path that add non-corresponding wavelength optical filter 35 can be passed through.
Realize this method as using the adjustable optical time-domain reflectomer 36 that uses the adjustable laser light source in inside, then can adjust the wavelength of light signal of the output of this adjustable optical time-domain reflectomer 36 equally, the optical filter 35 filtrable corresponding wavelength of corresponding indivedual branches light path 32, then can make the light signal of optical time domain reflectometer 39 can't be by adding branch's light path 32 of this corresponding wavelength optical filter 35, but other 32 of branch's light path that add non-corresponding wavelength optical filter 35 can be passed through.
For example, on one fen EPON of four, respectively in path A, B, C, the D use can be filtered corresponding wavelength and is respectively 1610,1615,1620 and the optical filter of the light signal of 1625nm wavelength, wherein the length of B and C is close, shown in Fig. 4 A, this is under the normal condition, utilize optical time domain reflectometer to measure the luminous power curve chart (being the trajectory diagram of optical time domain reflectometer) of the light signal that is received, a visible optical splitter and path A among the figure, B, C, the curve chart that the D terminal causes changes, respectively be path 21,22,23,24,25, when the adjustable optical filter is adjusted to 1615nm, the light signal that optical time domain reflectometer sends can't pass through path B, but path A, C, D can pass through.Shown in Fig. 4 B and Fig. 4 C, the luminous power curve chart that has shown the light signal that the optical time domain reflectometer measurement of present embodiment when incident takes place received, this moment is if there is an incident (Event) to take place on the B of path, on optical time domain reflectometer, can't present, yet the wavelength of adjusting light signal when the adjustable optical filter corresponds to path A, C, the corresponding wavelength 1610 of D, 1620, during 1625nm, the light signal of optical time domain reflectometer all can pass through path B, optical time domain reflectometer will present this incident to be taken place and occurrence positions 26 (shown in Fig. 4 B), add when the adjustable optical filter is adjusted corresponding wavelength in the light signal of respective path B, the optical time domain reflectometer performance is as good as shape (as Fig. 4 C), can the problem of analyzing be to betide on the B of path.
In addition, as shown in Figure 5, show the monitoring device of the fiber optic network that the second embodiment of the present invention provides, can be applicable to the real-time monitoring of EPON, be to carry out the transmission and the reception of light signal with optical transmission unit 44 by being respectively equipped with light receiving unit 43 with a plurality of Optical Network Terminal 42 at optical line terminal 41 as the fiber optic network 40 of EPON, and in optical line terminal 41 and a plurality of Optical Network Terminal 42, a planar optical waveguide 47 is set, received and the light signal that transmits to handle by light receiving unit 43 and optical transmission unit 44, and before a plurality of branches light path 46 of optical fiber 45, more utilize a wavelength-division to use (Wavelength Division Multiplexing more; WDM) coupler 48, connect optical line terminal 41 and adjustable optical time-domain reflectomer 50 by optical fiber 45, the light signal of different spectral composition can be introduced in each branch's light path 46, present embodiment also is arranged at a plurality of optical filters 51 each branch's light path 46 front end, be after the optical splitter 49, and owing to use the light signal of 1.3,1.49 and 1.5 mum wavelengths in this fiber optic network 40, present embodiment proposes to use adjustable optical time-domain reflectomer 50 light signals of 1.6 mum wavelengths, make when utilizing fiber optic network 40 to carry out transfer of data, can carry out the monitoring of real-time.
As shown in Figure 6, the monitoring device of the fiber optic network that the third embodiment of the present invention provided, can be applicable to the monitoring results of while for a plurality of EPONs, utilize computer 61 control light changeover modules (Optical Switch) 63 to automatically switch and monitor the path, and the optical fiber situation by adjustable optical time-domain reflectomer 62 monitoring fiber optic networks 60 or 70, wherein 64,71 are respectively fiber optic network 60, branch's light path of 70, in like manner, also can connect many group fiber optic networks, switching by the monitoring path, utilize single monitoring device can monitor the situation of each branch's light path on these fiber optic networks, improve the service efficiency of monitoring device.
Comprehensively above-mentioned, monitoring device and method according to fiber optic network provided by the present invention, fiber optic network at optical fiber with branch's light path, can clearly monitor out the situation of different branches light path, and solve when any two above branch optical path lengths are close, the problem of utilizing conventional method to differentiate fully, and, the present invention is except monitoring at the fiber optic network of non real-time (non-on-line), also can develop the optical fiber Condition Monitoring Technology of real-time (on-line) fiber optic network, even can develop the optical fiber condition monitoring system that a plurality of fiber optic networks.
Certainly; the present invention also can have other various embodiments; under the situation that does not deviate from spirit of the present invention and essence thereof; those of ordinary skill in the art work as can make various corresponding changes and distortion according to the present invention, but these corresponding changes and distortion all should belong to the protection range of the appended claim of the present invention.
Claims (10)
1, a kind of monitoring device of fiber optic network, be applied to have on the fiber optic network of optical fiber of a plurality of branches light path, described fiber optic network has the optical network terminal that comprises optical line terminal and a plurality of Optical Network Terminal, and optical line terminal is connected respectively to each Optical Network Terminal by the optical fiber with a plurality of branches light path, it is characterized in that the monitoring device of described fiber optic network comprises:
A plurality of optical filters be arranged at described branch light path front end respectively, and each described optical filter can filter the light signal of different corresponding wavelength;
One adjustable optical time-domain reflectomer, be connected in before the crosspoint of described branch light path of described optical fiber, arrive described branch light path in order to export light signal successively with each described corresponding wavelength, and the light signal that reflected of the described branch light path that receives each batch, with the situation that is used to analyze each batch light signal and judge each described branch light path, when judging not have damage corresponding to the luminous power curve of the reflected light signal of one of them described corresponding wavelength, and the luminous power curve of the reflected light signal of all the other described corresponding wavelength judges that damage is arranged, and judges then that branch's light path corresponding to the optical filter of one of them described corresponding wavelength diminishes to ruin.
2, the monitoring device of fiber optic network according to claim 1, it is characterized in that, described adjustable optical time-domain reflectomer comprises an adjustable optical filter and an optical time domain reflectometer, described optical time domain reflectometer is in order to export described light signal, described adjustable optical filter is arranged on after the described optical time domain reflectometer, in order to export behind the wavelength of adjusting described light signal.
3, the monitoring device of fiber optic network according to claim 1 is characterized in that, also comprises an optical splitter, is arranged on before the described branch light path, in order to described branch light path is imported in described light signal beam split.
4, the monitoring device of fiber optic network according to claim 1 is characterized in that, also comprises a light receiving unit and an optical transmission unit, is arranged at described optical network terminal, respectively in order to receive and to transmit described light signal.
5, the monitoring device of fiber optic network according to claim 4 is characterized in that, also includes a planar optical waveguide, is arranged on before the described branch light path, in order to handle the light signal that described light receiving unit and described optical transmission unit receive and transmit.
6, the monitoring device of fiber optic network according to claim 1 is characterized in that, also comprises an optical coupler, in order to described optical line terminal and described adjustable optical time-domain reflectomer are connected in described optical fiber.
7, the monitoring device of fiber optic network according to claim 6 is characterized in that, described optical coupler is that coupler is used in a wavelength-division more.
8, the monitoring device of fiber optic network according to claim 1 is characterized in that, described adjustable optical time-domain reflectomer inside is provided with an adjustable laser light source.
9, a kind of monitoring method of fiber optic network, be applied to have on the fiber optic network of optical fiber of a plurality of branches light path, described fiber optic network has the optical network terminal that comprises optical line terminal and a plurality of Optical Network Terminal, and optical line terminal is connected respectively to each Optical Network Terminal by the optical fiber with a plurality of branches light path, it is characterized in that described method includes the following step:
One optical filter is set in each described branch light path front end, described optical filter can filter the light signal of different corresponding wavelength respectively;
The adjustable optical time-domain reflectomer is imported light signal with described each corresponding wavelength successively to described branch light path, and makes described light signal be subjected to each different described optical filters respectively to filter;
The adjustable optical time-domain reflectomer receives the light signal that the light signal of described different corresponding wavelength is reflected by described branch light path in regular turn;
Analyze the light signal of described reflection; And
Judge the situation of each described branch light path, when judging not have damage corresponding to the luminous power curve of the reflected light signal of one of them described corresponding wavelength, and the luminous power curve of the reflected light signal of all the other described corresponding wavelength judges that damage is arranged, and judges then that branch's light path corresponding to the optical filter of one of them described corresponding wavelength diminishes to ruin.
10, the monitoring method of fiber optic network according to claim 9 is characterized in that, also comprises:
The step of monitoring for a plurality of EPONs is utilized computer control light changeover module to automatically switch and is monitored the path simultaneously, and monitors the optical fiber situation of fiber optic network by the adjustable optical time-domain reflectomer.
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| CNB2005100678788A CN100558013C (en) | 2005-04-29 | 2005-04-29 | A kind of monitoring device of fiber optic network and method |
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| CNB2005100678788A CN100558013C (en) | 2005-04-29 | 2005-04-29 | A kind of monitoring device of fiber optic network and method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| US11470117B2 (en) * | 2020-05-18 | 2022-10-11 | Nec Corporation | Physical layer security in network sensing architecture |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102067483A (en) * | 2008-04-21 | 2011-05-18 | 奥普林克通信公司 | Fiber network monitoring |
| US8594496B2 (en) * | 2009-11-13 | 2013-11-26 | Futurewei Technologies, Inc. | Tunable coherent optical time division reflectometry |
| CN102118658B (en) * | 2009-12-31 | 2014-02-19 | 华为技术有限公司 | Method and device for port identification of light splitter |
| CN102244538B (en) * | 2010-05-10 | 2015-06-17 | 华为技术有限公司 | System and method for detecting sub-optical fibers, ODN (optical distribution network) and optical splitter |
| CN102244539B (en) * | 2010-05-11 | 2014-09-17 | 华为技术有限公司 | Method and system for detecting branch optical fibers, PON (passive optical network) and optical splitter |
| CN102244541A (en) * | 2010-05-13 | 2011-11-16 | 华为技术有限公司 | Detection method, system and device for P2MP (point to multi-point) optical network |
| CN102195707B (en) * | 2011-03-24 | 2014-07-09 | 无锡路通视信网络股份有限公司 | Cascade type automatic monitoring system of optical cable |
| CN103166699A (en) * | 2011-12-16 | 2013-06-19 | 中国电信股份有限公司 | Method and system for positioning fault of optical fiber behind optical splitter in passive optical network (PON) |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US11470117B2 (en) * | 2020-05-18 | 2022-10-11 | Nec Corporation | Physical layer security in network sensing architecture |
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