CN102098098B - System for detecting fiber faults of passive optical network - Google Patents
System for detecting fiber faults of passive optical network Download PDFInfo
- Publication number
- CN102098098B CN102098098B CN200910225448.2A CN200910225448A CN102098098B CN 102098098 B CN102098098 B CN 102098098B CN 200910225448 A CN200910225448 A CN 200910225448A CN 102098098 B CN102098098 B CN 102098098B
- Authority
- CN
- China
- Prior art keywords
- signal
- optical
- optical fiber
- otdr
- branch
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Optical Communication System (AREA)
Abstract
The invention discloses a system for detecting fiber faults of a passive optical network, which comprises optical time domain reflectometer (OTDR) equipment, a wave division multiplexing coupler, a wavelength selection coupler, a branched fiber selector and more than one wavelength selection router connected with an optical splitter; the wave division multiplexing coupler is connected with the OTDR equipment and an optical line terminal and is connected with the wavelength selection coupler through a trunk fiber; the wavelength selection coupler is connected with the optical splitter and the branched fiber selector; the branched fiber selector is connected with each wavelength selection router; and each wavelength selection router is connected with an optical network unit through a corresponding branched fiber. Any branched fiber to be detected is selected through an optical switch, thus the signals of the branched fibers with equal length are prevented from being superposed and cannot be distinguished; and the reflected signals of the OTDR of the branched fibers go around the optical splitter and return to the trunk fiber, so that the attenuation of the optical splitter, particularly the optical splitter with high splitting ratio on the reflected signals is avoided, and a detector of the OTDR is ensured to receive the reflected signals.
Description
Technical field
The present invention relates to communications field optical network system, relate in particular to a kind of system that detects fiber fault of passive optical network.
Background technology
Fast development and maturation and the cost degradation of more than ten years optical fiber communication technology recently, make that Fiber to the home becomes the more and more reality of universalness, broadband access progressively replaces existing copper cash (wired) system with optical fiber like this, and light entering and copper back has become a kind of trend.And EPON be exactly wherein the widest the soonest and a kind of broadband access technology of environmental protection, accepted and be deployed by most operator, in order to meet growing communication user and quicker and better demand for services.
EPON (PON, Passive Optical Network) is a kind of optical fiber access technology of point-to-multipoint, as shown in Figure 1.EPON comprises optical line terminal (OLT, Optical Line Terminal), optical network unit (ONU, Optical Network Unit) and Optical Distribution Network (ODN, Optical Distribution Network).Normally connect by the power splitter (abbreviation optical splitter) of Optical Distribution Network ODN the point-to-multipoint structure that multiple optical network unit ONU form by an optical line terminal OLT.
After the arrangement and deployment of a large amount of EPONs, need to consider the operation and maintenance of this network, the special detection of fibre circuit and the location of fault.In order to reduce operation and maintenance cost, operator wishes to detect with a light path checkout equipment (OTDR) at OLT place trunk and the branch optical fiber of whole EPON, if a branch optical fiber breaks down, wish, in the case of not affecting the business of other branch optical fiber, can find rapidly fault and fault is positioned and keeped in repair.
In the time that this point-to-multipoint network detects with OTDR in OLT place of office side, the signal of trunk optical fiber does not generally have problem, but the signal of branch optical fiber all will run into following two problems.
One,, when as roughly equal to the distance of optical splitter in fruit part branch optical fiber, it is the signal of which branch optical fiber on earth that OTDR can not differentiate, unless used high-resolution OTDR.But the highest resolution that now can provide is 2 meters.
If the light splitting ratio of two optical splitters is very large, when at this moment the Rayleigh reflected signal of branch optical fiber is through optical splitter, will there is very large loss, while waiting it to arrive the detector of OTDR, signal has been submerged in noise and has suffered.
For example: for 10 kilometers of ODN of 1: 32 splitting ratio, the loss of optical splitter is 3*5+3=18dB. and 10 kilometers of fibre losses are 0.35*10=3.5dB.The dynamic range of general OTDR equipment is 35 to 40dB.As the signal of OTDR arrives the then total reflection of end (disregarding reflection loss) of branch optical fiber through the detector of optical splitter arrival OTDR through optical splitter.If disregard other loss (as junction loss etc.), the at this moment full light path loss of the signal of OTDR will be 2*18+2*3.5=42dB.This has exceeded the trend of work scope of OTDR equipment, and therefore the signal of branch optical fiber has been submerged in noise.The OTDR equipment that this explanation tradition is used in office side is the fault that can not measure the branch optical fiber of the ODN of large splitting ratio.This phenomenon is more universal, and the PON to very little splitting ratio even for various reasons in the PON network of laying in reality can not see the reflected signal of branch optical fiber with common OTDR instrument.
Existing remedial measure is before all ONU, to add an optical filter, the light below all 1625nm of this filter transmission, but the light of more than reflection 1625nm OTDR, as shown in Figure 2.Adopt after optical filter, the light of port reflection can increase 6dB.Mix high-resolution OTDR equipment, can, according to whether having reverberation to determine whether branch optical fiber has fault, still still can not determine the accurate location that branch optical fiber fault occurs like this.If there is part branch optical fiber length substantially equal, it is overlapping for the light of reflection, even high-resolution OTDR equipment can not be differentiated difference wherein.Worse for the ODN (as: more than 1: 128 splitting ratio) of large splitting ratio, likely also the be nowhere near loss of optical splitter of the gain that filter brings, therefore at the OTDR of office side equipment by any information likely can not receive from branch optical fiber.
Summary of the invention
The invention provides a kind of system and method that detects fiber fault of passive optical network, in order to solve the fault that can detect and locate any branch optical fiber in office side with OTDR equipment.
A kind of system that detects fiber fault of passive optical network that the embodiment of the present invention provides, comprising: light path detects OTDR equipment, wave division multiplex coupler, wavelength selective coupler, branch optical fiber selector and an above wavelength being connected with optical splitter and selects router; Wave division multiplex coupler is connected with OTDR equipment and optical line terminal, and is connected with wavelength selective coupler by trunk optical fiber; Wavelength selective coupler is connected with optical splitter and branch optical fiber selector; Branch optical fiber selector selects router to be connected with each wavelength; Each wavelength selects router to be connected with optical network unit by corresponding branch optical fiber respectively,
OTDR equipment, for the OTDR control signal to respective branch optical fiber and OTDR detectable signal to wave division multiplex coupler emission needle, and whether reflected signal corresponding to the described OTDR detectable signal of receiving according to analysis to determine whether trunk optical fiber or respective branch optical fiber exist fault extremely;
Wave division multiplex coupler, for the downstream signal of OTDR signal and optical line terminal is imported to trunk optical fiber, described OTDR signal is for the OTDR control signal of respective branch optical fiber or OTDR detectable signal; The reflected signal of separating on trunk optical fiber is passed to OTDR equipment, and isolated upward signal is passed to optical line terminal;
Wavelength selective coupler, for isolate a part of OTDR signal from trunk optical fiber, and is passed to branch optical fiber selector; Another part OTDR signal is passed to optical splitter; The reflected signal of the branch optical fiber of receiving is led and got back on trunk optical fiber, the upward signal of the optical network unit by optical splitter is sent on trunk optical fiber simultaneously; And send the downstream signal of optical line terminal to optical splitter;
Branch optical fiber selector, in the time that described OTDR signal is OTDR control signal, controls the by-pass switch of respective branch optical fiber according to this OTDR control signal, and the reflected signal of corresponding branch optical fiber is delivered to wavelength selective coupler;
Wavelength is selected router, for the downstream signal from optical splitter is passed to branch optical fiber; From the upward signal of branch optical fiber, isolate reflected signal and pass to branch optical fiber selector, and isolated upward signal is passed to optical splitter.
Described wave division multiplex coupler is optical filter, for the OTDR signal coupling of OTDR equipment output is entered to trunk optical fiber, and passes on OTDR equipment after the reflected signal on trunk optical fiber is separated.
Described wavelength selective coupler comprises: the first optical filter, and branch coupler and the second optical filter, wherein,
The first optical filter, for isolating OTDR signal guide to branch coupler from trunk optical fiber; The reflected signal of the branch optical fiber from branch coupler is coupled back in trunk optical fiber; To be coupled back in trunk optical fiber from the upward signal of the second optical filter;
Branch coupler, for OTDR signal is shunted, by a part of OTDR signal guide to the second optical filter, by another part OTDR signal guide to branch optical fiber selector; And the reflected signal of branch optical fiber is passed to the first optical filter;
The second optical filter, for by the OTDR signal guide of receiving to optical splitter; To be directed to the first optical filter from the upward signal of optical splitter.
Described branch optical fiber selector comprises:
Optical circulator, for importing to photo-detector by OTDR signal; The reflected signal of branch optical fiber is delivered on wavelength selective coupler;
Photo-detector, for OTDR signal is converted to the signal of telecommunication, and passes to optical switch controller by this signal of telecommunication;
Optical switch controller, for according to judging from the signal of telecommunication of photo-detector, if this signal of telecommunication is the switch controlling signal of being changed by OTDR control signal, triggers optical switch and carries out the action of the by-pass switch of corresponding branch optical fiber being carried out to switch control; If this signal of telecommunication is the signal of being changed by OTDR detectable signal, do not carry out any action, in state undetermined;
Light opens the light, and for the switch controlling signal sending according to optical switch controller, the by-pass switch of corresponding branch optical fiber is carried out to switch control.
Described wavelength is selected router, comprising: the first optical circulator, the second optical circulator and optical filter, wherein,
The first optical circulator, for downstream signal being directed to the second optical circulator, is directed to optical splitter by upward signal;
Optical filter, for the reflected signal of branch optical fiber is separated from upward signal, and guiding is to branch optical fiber selector; Isolated upward signal is directed to the first optical circulator;
The second optical circulator, for downlink optical signal is directed to branch optical fiber, and is directed to optical filter by uplink optical signal.
Described branch optical fiber selector, for being while being used to indicate the instruction of respective branch optical fiber closure when OTDR control signal, generates the control signal of the by-pass switch to connecting respective branch optical fiber according to OTDR control signal, connect corresponding wavelength and select router.
Described branch optical fiber selector, for being while being used to indicate the instruction of respective branch optical fiber disconnection when OTDR control signal, generates the control signal of the by-pass switch to disconnecting respective branch optical fiber according to OTDR control signal, disconnect corresponding wavelength and select router.
Described branch optical fiber selector also comprises power module, is used to photo-detector, optical switch controller and optical switch to power.
Described optical switch controller, if the control signal that to be further used for switch controlling signal that this signal of telecommunication is corresponding be closed optical switch,, before the execution of triggering optical switch is carried out the action of switch control to the by-pass switch of corresponding branch optical fiber, instruction power module is carried out the operation of connecting optical switch power supply; If the switch controlling signal that this signal of telecommunication is corresponding is the control signal that disconnects optical switch,, after the execution of triggering optical switch is carried out the action of switch control to the by-pass switch of corresponding branch optical fiber, instruction power module is carried out the operation that disconnects optical switch power supply;
Described power module, for power to photo-detector, optical switch controller always; According to the instruction of described optical switch controller, control the power supply to optical switch.
The system of the embodiment of the present invention can monitor, detects and locate the fault of trunk and all branch optical fiber of EPON, and can select a branch optical fiber of any required detection by optical switch, so just avoid the signal overlap of branch optical fiber equal in length, can not distinguish.Allow the reflected signal of OTDR of branch optical fiber walk around optical splitter simultaneously and get back to trunk optical fiber, so just avoided the particularly optical splitter of the large splitting ratio decay to this reflected signal of optical splitter, ensured that the detector of OTDR can receive this signal.
Brief description of the drawings
Fig. 1 is the structural representation of existing EPON;
Fig. 2 is the structural representation that existing light path detects passive optical network;
Fig. 3 is the structural representation that light path of the present invention detects passive optical network;
Fig. 4 is the structural representation of wave division multiplex coupler of the present invention;
Fig. 5 is the structural representation of wavelength selective coupler of the present invention;
Fig. 6 is the structural representation of branch optical fiber selector of the present invention;
Fig. 7 is the structural representation that wavelength of the present invention is selected router.
Embodiment
Shown in Figure 3, the system of the embodiment of the present invention comprises: OTDR equipment 31, wave division multiplex coupler 32, wavelength selective coupler 33, branch optical fiber selector 34 and an above wavelength being connected with optical splitter are selected router three 5.Wherein, wave division multiplex coupler 32 is connected with OTDR equipment 31 and optical line terminal; Be connected with wavelength selective coupler 33 by trunk optical fiber; Wavelength selective coupler 33 is connected with optical splitter and branch optical fiber selector 34; Branch optical fiber selector 34 selects router three 5 to be connected with each wavelength; Each wavelength selects router three 5 to be connected with optical network unit by corresponding branch optical fiber respectively.
OTDR equipment 31, for the OTDR control signal to respective branch optical fiber and OTDR detectable signal to wave division multiplex coupler emission needle, and receive according to analysis whether the reflected signal that described OTDR detectable signal is corresponding comes to determine whether trunk optical fiber and respective branch optical fiber exist fault extremely.
Here, if being Fresnel reflection signal or Rayleigh reflected signal, reflected signal has sudden change, can determine whether trunk optical fiber or respective branch optical fiber exist fault, if continuous Rayleigh reflected signal can determine that trunk optical fiber or respective branch optical fiber do not break down.
Wave division multiplex coupler 32, for the OTDR signal of receiving and the downstream signal of optical line terminal are imported to trunk optical fiber, described OTDR signal is for the OTDR control signal of respective branch optical fiber or OTDR detectable signal; The reflected signal of separating on trunk optical fiber is passed to OTDR equipment, and isolated upward signal is passed to optical line terminal.
Wavelength selective coupler 33, for isolate a part of OTDR signal from trunk optical fiber, and is passed to branch optical fiber selector; Another part OTDR signal is passed to optical splitter; The reflected signal of the branch optical fiber of receiving is led and got back on trunk optical fiber, the upward signal of the optical network unit by optical splitter is sent on trunk optical fiber simultaneously; The downstream signal transmitting from trunk optical fiber is passed to optical splitter simultaneously.And in embodiments of the present invention, optical splitter is passed to corresponding wavelength by the downstream signal of receiving and selected router, can also be used for the upward signal of receiving to pass to wavelength selective coupler.
Branch optical fiber selector 34, in the time that described OTDR signal is OTDR control signal, controls the by-pass switch of respective branch optical fiber according to this OTDR control signal, and the reflected signal of corresponding branch optical fiber is delivered to wavelength selective coupler;
Wavelength is selected router three 5, for the downstream signal from optical splitter is passed to branch optical fiber; From the upward signal of branch optical fiber, isolate reflected signal and pass to branch optical fiber selector, and will isolate upward signal and pass to optical splitter.
Described wave division multiplex coupler 32 is positioned at OLT place of office side, and object, in the time not affecting regular traffic, imports OTDR signal and derive.Shown in Figure 4, wave division multiplex coupler can be made up of a film filter (TFF).This film filter all reflects light more than 1625nm, but to the equal transmission of the light below 1625nm.Connection between them is as follows, and P port is connected with OLT, and C port is connected with the trunk optical fiber of ODN, and R port is connected with the equipment of OTDR.This film filter imports to trunk optical fiber for the OTDR signal that OTDR equipment is exported, and the reflected signal on trunk optical fiber is passed to OTDR equipment, keeps the normal up-downgoing communication contact of OLT and ONU simultaneously.
In embodiments of the present invention, in the porch of optical splitter, a wavelength selective coupler can be set, shown in Figure 5, described wavelength selective coupler can comprise: the first optical filter 51, and branch coupler 53 and the second optical filter 52, wherein,
The first optical filter 51, it is a sideband filter, to light total reflection more than 1625nm, the light total transmissivity of other wavelength, the transmission mouth (P) of the first optical filter 51 is connected with the transmission mouth (P) of the second optical filter 52; General mouthful (C) of the first optical filter 51 is connected with trunk optical fiber, and the reflex port (R) of the first optical filter 51 is connected with branch coupler 53 interfaces.The first optical filter 51 is for isolating OTDR signal guide to branch coupler 53 from trunk optical fiber; The reflected signal of the branch optical fiber from branch coupler 53 is coupled back in trunk optical fiber; To be coupled back in trunk optical fiber from the upward signal of the second optical filter 52.
Branch coupler (Tap Coupler) 53, for OTDR signal is shunted, R mouth by a part of OTDR signal guide to the second optical filter 52, by another part OTDR signal guide to branch optical fiber selector, if OTDR signal is control signal, branch optical fiber selector can be carried out related command so, selects to be communicated with certain branch optical fiber etc. as required; And the reflected signal of branch optical fiber is passed to the first optical filter 51, the reflected signal of this branch optical fiber can be led back trunk optical fiber by branch coupler 53 and the first optical filter 51 like this.
The second optical filter 52, it is a sideband filter, it is to light total reflection more than 1625nm, the equal transmission of other light, its transmission mouth (P) is connected with the transmission mouth (P) of the first optical filter 51; Its general mouthful (C) is connected with optical splitter interface, and its reflex port (R) is connected with the main diffluence pass of branch coupler 53.The second optical filter 52 for by the OTDR signal guide of receiving to optical splitter; The first optical filter 51 will be directed to from the upward signal of optical splitter.The light that simultaneously ensures up-downgoing is unobstructed, is not diverted to the branch road of OTDR.
At the other selector that has a branch optical fiber of optical splitter of Optical Distribution Network ODN, the selector of branch optical fiber is an active device, and it can or use battery by power supplied locally.Can consider that long-range using up power if certainly disregard cost.In order to reduce as much as possible power consumption, should be in state undetermined in the time not detecting.Shown in Figure 6, branch optical fiber selector 34 comprises: light opens the light 61, optical circulator 62, photo-detector 63 and optical switch controller 64.
Light opens the light and 61 for the switch controlling signal sending according to optical switch controller, the by-pass switch of corresponding branch optical fiber is carried out to switch control, namely selects to need the branch optical fiber measured, and the reflected signal of this branch optical fiber is passed to optical circulator.
Optical circulator 62, for importing to photo-detector by described OTDR signal; The reflected signal of branch optical fiber is delivered on wavelength selective coupler.As: as described in OTDR signal can open the control signal of optical switch while being OTDR control signal, can be to select corresponding branch optical fiber be communicated with or close.
Photo-detector 63 is for OTDR signal is converted to the signal of telecommunication, and this signal of telecommunication is passed to optical switch controller.
Optical switch controller 64, judge from the signal of telecommunication of photo-detector for basis, if this signal of telecommunication is the switch controlling signal of being changed by OTDR control signal, triggers optical switch and carry out the action of the by-pass switch of corresponding branch optical fiber being carried out to switch control; If this signal of telecommunication is the signal of being changed by OTDR detectable signal, do not carry out any action, in state undetermined.
Can further include: power module, not shown in the figures meaning out, is used to photo-detector, optical switch controller and optical switch to power.
Described power module, can always be photo-detector, optical switch controller and optical switch and powers.Certainly, in order to economize on electricity, can be for photo-detector, optical switch controller are powered always, but need to, according to the instruction of described optical switch controller, control the power supply to optical switch.This needs described optical switch controller, if be further used for switch controlling signal that this signal of telecommunication is corresponding and be the control signal of the optical switch that closed pair answers,, before the execution of triggering optical switch is carried out the action of switch control to the by-pass switch of corresponding branch optical fiber, instruction power module is carried out the operation of connecting optical switch power supply; If the switch controlling signal that this signal of telecommunication is corresponding is the control signal that disconnects corresponding optical switch,, after the execution of triggering optical switch is carried out the action of switch control to the by-pass switch of corresponding branch optical fiber, instruction power module is carried out the operation that disconnects optical switch power supply.
Before each branch optical fiber of optical splitter, connect a wavelength and select router, shown in Figure 7, wavelength is selected router three 5, comprising: the first optical circulator 71, the second optical circulator 72 and optical filter 73.
The first optical circulator 71, for downstream signal is directed to the second optical circulator 72, upward signal is directed to optical splitter, that is: descending light is arrived to port 3 by port 2, arrive branch optical fiber through the second optical circulator 72, receive the up light transmitting through film filter at port one, and up light is passed to and reached optical splitter by port 2.
Optical filter 73 is sideband filters, all identical with sideband filter above, it all reflects light more than 1625nm, the equal transmission of remaining light, for the reflected signal of branch optical fiber is separated from the up signal of ONU, and guiding is to branch optical fiber selector; Isolated upward signal is directed to the first optical circulator 71;
The second optical circulator 72, for downlink optical signal is directed to branch optical fiber by port one to port 2, and arrives uplink optical signal guiding in sideband filter 73 to port 3 by port 2.
The embodiment of the present invention, by the light path detection system of above a series of fill-in light functional module compositions, can, in office side with a common OTDR equipment, detect rapidly and locate intelligently the fault of trunk optical fiber and any branch optical fiber.And can select a branch optical fiber of any required detection by optical switch, and so just avoiding the signal overlap of branch optical fiber equal in length, can not distinguish.Allow the reflected signal of OTDR of branch optical fiber walk around optical splitter simultaneously and get back to trunk optical fiber, so just avoided the particularly optical splitter of the large splitting ratio decay to this reflected signal of optical splitter, ensured that the instrument of OTDR can receive this signal.
By the system of the embodiment of the present invention, can very effectively help operator to find fast location of fault, this will shorten the time of maintenance greatly, reduces maintenance cost.When particularly certain branch optical fiber breaks down, operator can, in the time not affecting the regular traffic of other branch optical fibers, detect and fault location this optical fiber, and keep in repair rapidly.These all will reduce the operation and maintenance cost of operator greatly.
Below in conjunction with accompanying drawing and preferred embodiment, technical scheme of the present invention is at length set forth.The embodiment below exemplifying is only for description and interpretation the present invention, and do not form the restriction to technical solution of the present invention.
In order to realize the fibre system that detects intelligently EPON, first EPON is done to some transformations, increase some active and passive optical function modules.According to the requirement of Fig. 3, increased a wave division multiplex coupler at OLT place, its major function be OTDR equipment connection on trunk optical fiber, make OTDR signal can enter passive optical network, corresponding reflected signal can pass on the detector of OTDR by network.
Before optical splitter, insert wavelength selective coupler, its major function is that the index signal of OTDR is passed to branch optical fiber selector, and the reflected signal of branch optical fiber is passed back to trunk optical fiber.It ensures that normal communication and the OTDR detectable signal of uplink and downlink signals pass through simultaneously.
After optical splitter, before each branch optical fiber, insert wavelength and select router, its major function is that the reflected signal of branch optical fiber is passed on branch optical fiber selector, and the communication of up-downgoing simultaneously normally moves.
Put branch optical fiber selector on optical splitter side, its one end is connected with wavelength selective coupler, and the other end selects router to be connected with each wavelength.Its major function is the requirement according to OTDR, opens branch optical fiber selector, connects the bypass of corresponding branch optical fiber, is completed and closes this bypass.Because branch optical fiber selector is active equipment, in order to meet power saving that industry is general and the requirement of environmental protection, in the time not testing, generally in state undetermined, only have photo-detector and optical switch controller to have induction power supply, other parts are not powered; In the time that needs are tested, first OTDR control signal need to be sent activation instruction, optical switch control order restores electricity, all modules obtain normal power supply, at this moment branch optical fiber selector is in state of activation: then OTDR control signal is sent relevant instruction, optical switch control order correlation module is carried out associative operation, and at this moment branch optical fiber selector is in exectorial state; After task completes, OTDR control signal can be sent and close or instruction undetermined, and optical switch control order is closed the power supply of correlation module, and at this moment branch optical fiber selector returns to state undetermined.
Particularly, whole workflow and the state variation of branch optical fiber selector are as follows: when (1) receives electric power starting order, branch optical fiber selector is transformed into state of activation from state undetermined; (2) receive that OTDR control signal is while controlling the order of respective branch optical fiber closure, branch optical fiber selector order is carried out the optical link of relevant action connection respective branch optical fiber; (3), while receiving OTDR detectable signal, branch optical fiber selector is in carrying out test mode; (4), after being completed, it is the power supply that disconnects corresponding optical switch that branch optical fiber selector receives OTDR control signal; (5) carry out after power supply ON-and OFF-command, get back to state undetermined.
After all these modules are pressed Fig. 3 connection, the equipment of OTDR just can be tested whole passive optical network intelligently.Below whole light path testing process is described.
In the time that EPON need to detect, first in office side, the equipment of OTDR is connected on wave division multiplex coupler, then OTDR signals to branch optical fiber selector with 1625nm or above light, the C mouth of the first optical filter of this light process wavelength selective coupler is to the B of the branch mouth of branch coupler, then the optical circulator that arrives branch optical fiber selector arrives photo-detector PD, detector becomes the signal of telecommunication light signal, open optical switch according to the requirement of control signal, tell optical switch that the light path of the branch optical fiber that will detect is connected simultaneously simultaneously.Optical switch is connected the link of this branch optical fiber as requested.
OTDR, after waiting for several seconds, starts to send test light pulse.This signal enters trunk optical fiber through wave division multiplex coupler.At this moment the reflected signal of trunk optical fiber, transfers back to by trunk optical fiber on the detector of OTDR.If trunk optical fiber has any fault, OTDR can find very soon, and can locate very soon.Arrive the OTDR signal of wavelength selective coupler, arrive branch coupler from the C oral reflex of the first optical filter to R mouth, most OTDR signals are divided on the second optical filter, arrive on optical splitter by its C mouth, then enter each branch optical fiber.First it will select router through each wavelength,, through the first optical circulator and the second optical circulator, arrives each branch optical fiber, then arrives ONU through each branch optical fiber.At this moment the reflected signal of branch optical fiber, arrives wavelength through branch optical fiber and selects router, is then directed to sideband filter by the second optical circulator, through reflecting into light inlet switching branches.If this branch road is connected, this reflected signal will be introduced in wavelength selective coupler through optical switch path so, then pass through branch coupler, and sideband filter returns to trunk optical fiber.Clearly this signal has been walked around optical splitter, arrives the detector of OTDR through the transmission of trunk optical fiber.If this branch road is not connected, this signal will stop its stroke so.So can only measure a branch optical fiber at every turn.
After measurement finishes, OTDR launches shutdown signal again, arrives branch optical fiber selector by wavelength selective coupler, and optical switch controller cuts out optical switch according to the instruction of signal.Whole branch optical fiber selector is by the state undetermined in low energy consumption.
Refer now to and see the communication between OLT and ONU in testing process.See Fig. 3.First be descending optical link, OLT sends descending light, through the transmission of wave division multiplex coupler, see Fig. 4, arrive wavelength selective coupler through trunk optical fiber, see Fig. 5, then see through the first optical filter and the second optical filter and arrive optical splitter, arrive each wavelength through the light splitting of optical splitter and select router, see Fig. 7, arrive each branch optical fiber through the first optical circulator and the second optical circulator, then arrive corresponding ONU by branch optical fiber.Up optical link is the up light being sent by ONU, arrive wavelength through branch optical fiber and select router, see Fig. 7, first it arrives sideband filter by the second optical circulator, see through sideband filter and arrive the first optical circulator, arrive optical splitter through the first optical circulator, arrive wavelength selective coupler through optical splitter, see Fig. 5, see through the second optical filter and the first optical filter and arrive trunk optical fiber, arrive wave division multiplex coupler through trunk optical fiber, see Fig. 4, see through coupler and arrive OLT place.In whole transmitting procedure, the signal of OTDR and reflected signal do not have any interference to descending and up optical link.
Detect in the process from starting to closing at whole light path, the communication between OLT and the ONU of EPON remains unimpeded, and namely their business is not interrupted.If there is a branch optical fiber to break down, detect and fault location with OTDR in office side, and in follow-up reparation and recovery normal operating conditions process, not perception to some extent of the user of other branch optical fibers.This will greatly reduce the cost of maintenance of operator.
Obviously, those skilled in the art can carry out various changes and modification and not depart from the spirit and scope of the present invention the present invention.Like this, if these amendments of the present invention and within modification belongs to the scope of the claims in the present invention and equivalent technologies thereof, the present invention is also intended to comprise these changes and modification interior.
Claims (9)
1. a system that detects fiber fault of passive optical network, is characterized in that, comprising: light path detects OTDR equipment, wave division multiplex coupler, wavelength selective coupler, branch optical fiber selector and an above wavelength being connected with optical splitter and selects router; Wave division multiplex coupler is connected with OTDR equipment and optical line terminal, and is connected with wavelength selective coupler by trunk optical fiber; Wavelength selective coupler is connected with optical splitter and branch optical fiber selector; Branch optical fiber selector selects router to be connected with each wavelength; Each wavelength selects router to be connected with optical network unit by corresponding branch optical fiber respectively,
OTDR equipment, for the OTDR control signal to respective branch optical fiber and OTDR detectable signal to wave division multiplex coupler emission needle, and whether reflected signal corresponding to the described OTDR detectable signal of receiving according to analysis to determine whether trunk optical fiber or respective branch optical fiber exist fault extremely;
Wave division multiplex coupler, for the downstream signal of OTDR signal and optical line terminal is imported to trunk optical fiber, described OTDR signal is for the OTDR control signal of respective branch optical fiber or OTDR detectable signal; The reflected signal of separating on trunk optical fiber is passed to OTDR equipment, and isolated upward signal is passed to optical line terminal;
Wavelength selective coupler, for isolate a part of OTDR signal from trunk optical fiber, and is passed to branch optical fiber selector; Another part OTDR signal is passed to optical splitter; The reflected signal of the branch optical fiber of receiving is led and got back on trunk optical fiber, the upward signal of the optical network unit by optical splitter is sent on trunk optical fiber simultaneously; And send the downstream signal of optical line terminal to optical splitter;
Branch optical fiber selector, in the time that described OTDR signal is OTDR control signal, controls the by-pass switch of respective branch optical fiber according to this OTDR control signal, and the reflected signal of corresponding branch optical fiber is delivered to wavelength selective coupler;
Wavelength is selected router, for the downstream signal from optical splitter is passed to branch optical fiber; From the upward signal of branch optical fiber, isolate reflected signal and pass to branch optical fiber selector, and isolated upward signal is passed to optical splitter;
Described branch optical fiber selector comprises:
Optical circulator, for importing to photo-detector by OTDR signal; The reflected signal of branch optical fiber is delivered on wavelength selective coupler;
Photo-detector, for OTDR signal is converted to the signal of telecommunication, and passes to optical switch controller by this signal of telecommunication;
Optical switch controller, for according to judging from the signal of telecommunication of photo-detector, if this signal of telecommunication is the switch controlling signal of being changed by OTDR control signal, triggers optical switch and carries out the action of the by-pass switch of corresponding branch optical fiber being carried out to switch control; If this signal of telecommunication is the signal of being changed by OTDR detectable signal, do not carry out any action, in state undetermined;
Light opens the light, and for the switch controlling signal sending according to optical switch controller, the by-pass switch of corresponding branch optical fiber is carried out to switch control.
2. system according to claim 1, is characterized in that, described wave division multiplex coupler is optical filter, for the OTDR signal coupling of OTDR equipment output is entered to trunk optical fiber, and passes on OTDR equipment after the reflected signal on trunk optical fiber is separated.
3. system according to claim 1, is characterized in that, described wavelength selective coupler comprises: the first optical filter, and branch coupler and the second optical filter, wherein,
The first optical filter, for isolating OTDR signal guide to branch coupler from trunk optical fiber; The reflected signal of the branch optical fiber from branch coupler is coupled back in trunk optical fiber; To be coupled back in trunk optical fiber from the upward signal of the second optical filter;
Branch coupler, for OTDR signal is shunted, by a part of OTDR signal guide to the second optical filter, by another part OTDR signal guide to branch optical fiber selector; And the reflected signal of branch optical fiber is passed to the first optical filter;
The second optical filter, for by the OTDR signal guide of receiving to optical splitter; To be directed to the first optical filter from the upward signal of optical splitter.
4. system according to claim 1, is characterized in that, described wavelength is selected router, comprising: the first optical circulator, the second optical circulator and optical filter, wherein,
The first optical circulator, for downstream signal being directed to the second optical circulator, is directed to optical splitter by upward signal;
Optical filter, for the reflected signal of branch optical fiber is separated from upward signal, and guiding is to branch optical fiber selector; Isolated upward signal is directed to the first optical circulator;
The second optical circulator, for downlink optical signal is directed to branch optical fiber, and is directed to optical filter by uplink optical signal.
5. system according to claim 1, it is characterized in that, described branch optical fiber selector, for when OTDR control signal be while being used to indicate the instruction of respective branch optical fiber closure, generate the control signal of the by-pass switch to connecting respective branch optical fiber according to OTDR control signal, connect corresponding wavelength and select router.
6. system according to claim 1, it is characterized in that, described branch optical fiber selector, for being while being used to indicate the instruction of respective branch optical fiber disconnection when OTDR control signal, generate the control signal of the by-pass switch to disconnecting respective branch optical fiber according to OTDR control signal, disconnect corresponding wavelength and select router.
7. system according to claim 1, is characterized in that, described branch optical fiber selector also comprises power module, is used to photo-detector, optical switch controller and optical switch to power.
8. system according to claim 7, it is characterized in that, described optical switch controller, if the control signal that to be further used for switch controlling signal that this signal of telecommunication is corresponding be closed optical switch, trigger before optical switch carries out the by-pass switch of corresponding branch optical fiber is carried out to the action of switch control, instruction power module is carried out the operation of connecting optical switch power supply; If the switch controlling signal that this signal of telecommunication is corresponding is to disconnect the control signal of optical switch, trigger after optical switch carries out the by-pass switch of corresponding branch optical fiber is carried out to the action of switch control, instruction power module is carried out the operation that disconnects optical switch power supply;
Described power module, for power to photo-detector, optical switch controller always; According to the instruction of described optical switch controller, control the power supply to optical switch.
9. system according to claim 1, is characterized in that, the operating state of described branch optical fiber selector comprises: state of activation, on-state, test mode, closed condition and state undetermined.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910225448.2A CN102098098B (en) | 2009-12-14 | 2009-12-14 | System for detecting fiber faults of passive optical network |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200910225448.2A CN102098098B (en) | 2009-12-14 | 2009-12-14 | System for detecting fiber faults of passive optical network |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102098098A CN102098098A (en) | 2011-06-15 |
| CN102098098B true CN102098098B (en) | 2014-09-10 |
Family
ID=44130983
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200910225448.2A Active CN102098098B (en) | 2009-12-14 | 2009-12-14 | System for detecting fiber faults of passive optical network |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102098098B (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101924590B (en) * | 2010-08-25 | 2016-04-13 | 中兴通讯股份有限公司 | The detection system of fiber fault of passive optical network and method |
| CN101984561B (en) * | 2010-11-15 | 2014-09-10 | 中兴通讯股份有限公司 | System and method for detecting optical fiber faults of passive optical network |
| WO2013055105A1 (en) * | 2011-10-11 | 2013-04-18 | Ls Cable Ltd. | Optical line monitoring system and method |
| CN102523041B (en) * | 2011-12-31 | 2015-05-20 | 中国电子科技集团公司第四十一研究所 | Off-line and on-line test integrated multi-wavelength optical path component |
| CN104009796B (en) * | 2013-02-25 | 2017-04-05 | 中兴通讯股份有限公司 | A kind of fiber fault of passive optical network detection method and system |
| CN104038280A (en) * | 2013-03-04 | 2014-09-10 | 中兴通讯股份有限公司 | Fiber fault detection system and method of passive optical network |
| CN104518825B (en) * | 2013-09-26 | 2018-10-09 | 上海诺基亚贝尔股份有限公司 | The intelligent splitter element that a kind of branch optical fiber for PON monitors |
| CN104683025B (en) * | 2013-12-02 | 2019-03-15 | 中国移动通信集团公司 | A method of detection Optical Distribution Network |
| WO2016090634A1 (en) * | 2014-12-12 | 2016-06-16 | 华为技术有限公司 | Passive optical network device |
| WO2016172886A1 (en) * | 2015-04-29 | 2016-11-03 | 华为技术有限公司 | Optical splitter, signal transmission method, and passive optical network |
| EP3357179A1 (en) * | 2015-09-30 | 2018-08-08 | Telefonaktiebolaget LM Ericsson (publ) | A network architecture, an optical communication network and use of an md-wss |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101304283A (en) * | 2008-07-04 | 2008-11-12 | 电子科技大学 | Method and device for fault localization and safety prevention detection using passive optical network |
-
2009
- 2009-12-14 CN CN200910225448.2A patent/CN102098098B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101304283A (en) * | 2008-07-04 | 2008-11-12 | 电子科技大学 | Method and device for fault localization and safety prevention detection using passive optical network |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102098098A (en) | 2011-06-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102098098B (en) | System for detecting fiber faults of passive optical network | |
| CN101984561B (en) | System and method for detecting optical fiber faults of passive optical network | |
| CN101924590B (en) | The detection system of fiber fault of passive optical network and method | |
| CN101924962B (en) | System and method thereof for detecting fiber faults | |
| EP2034635B1 (en) | A method for locating fiber event point and an optical network and network equipment thereof | |
| CN102208941B (en) | Fiber failure detection system, method, optical switch and passive optical network system | |
| CN101442691B (en) | Optical cable monitoring system based on passive optical network system | |
| CN102571199B (en) | A kind of fiber failure detection method and device | |
| CN102714545B (en) | Optical transceiver module, passive optical network system, optical fiber detection method and system | |
| CN102104423A (en) | Fault detection method and system for multi-branch PON (Passive Optical Network) | |
| CN102142893A (en) | Reflectance anomaly detection method, system and device for optical distribution network | |
| WO2012097554A1 (en) | Optical line terminal, passive optical network system and optical signal transmission method | |
| CN102201861B (en) | Based on the long fault detection system apart from EPON and method | |
| CN101232328A (en) | Method for locating case point of branch optical fiber, optical network and network appliance | |
| CN102932056A (en) | Method and device for detecting optical signal performance and diagnosing fiber link fault | |
| CN104601228A (en) | System and method for positioning PON network optical fiber link failures | |
| CN103905112A (en) | Method, device and system for fault detection of passive optical network | |
| CN110266374A (en) | It is a kind of can high precision monitor TDM-PON second level branch trouble device and method | |
| CN107078793B (en) | A kind of fiber fault diagnosis method, apparatus and system | |
| CN107070544A (en) | Optical assembly, detecting devices and decision method using the optical assembly | |
| CN101567724B (en) | Network situation detection system and method | |
| US8014670B2 (en) | Method and apparatus for testing and monitoring data communications in the presence of a coupler in an optical communications network | |
| CN104009794A (en) | Method and apparatus for detecting fault in optical fiber of passive optical network | |
| CN102928740B (en) | Intelligent collection type fault diagnosis and In-Line Temperature Measure System | |
| CN102281100B (en) | Long method and the device realizing light path detection in EPON |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |