CN207283565U - A kind of cascaded optical fiber phase compensator and fibre-optic transmission system (FOTS) - Google Patents
A kind of cascaded optical fiber phase compensator and fibre-optic transmission system (FOTS) Download PDFInfo
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- CN207283565U CN207283565U CN201721168838.7U CN201721168838U CN207283565U CN 207283565 U CN207283565 U CN 207283565U CN 201721168838 U CN201721168838 U CN 201721168838U CN 207283565 U CN207283565 U CN 207283565U
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- optical fiber
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Abstract
The utility model is a kind of cascaded optical fiber phase compensator and fibre-optic transmission system (FOTS), and the first wavelength division multiplexer of this compensator demultiplex point gained single longitudinal mode laser signal is a branch of to be sent into fibre optic interferometer as light source through optoisolator by optical fiber splitter beam splitting.Fibre optic interferometer test side connects fibre optic phase modulator through feedback control circuit, and first and second wavelength division multiplexer reflection end is connected, and business optical signal is sent into the second wavelength division multiplexer and single longitudinal mode laser again multiplex；Multiplex signal accesses this grade of Transmission Fibers after fibre optic phase modulator phase compensation.The Transmission Fibers of fibre-optic transmission system (FOTS) are divided into the multistage of every section≤25km, originating terminal fiber phase compensator is the fiber phase compensator containing single longitudinal mode laser, second segment plays every section of Transmission Fibers head end and adds a cascaded optical fiber phase compensator, reaches receiving terminal demultiplex and divides fiber termination box.Each cascade fiber phase compensator eliminates each section of phase drift, greatly reduces steady phase fibre-optic transmission system (FOTS) cost respectively without single longitudinal mode laser.
Description
Technical field
It the utility model is related to the stabilized fiber phase transmission equipment of optical fiber transmission radio frequency coherent signal, and in particular to one kind cascade
Fiber phase compensator and fibre-optic transmission system (FOTS).
Background technology
Fiber phase compensator is a kind of stabilized fiber phase transmission equipment applied to optical fiber transmission radio frequency coherent signal.It is existing
Transmitting terminal fiber phase compensator host include single longitudinal mode laser, fibre optic interferometer, feedback control circuit, wavelength-division multiplex
Device, the fibre optic phase modulator based on PZT, the demultiplex that the Transmission Fibers other end is formed for solution wavelength division multiplexer and fiber reflector
Divide fiber termination box.The equipment at Transmission Fibers both ends completes the fiber phase jitter compensation of Transmission Fibers jointly, and service signal exists
Transparent transmission in Transmission Fibers.
Since single longitudinal mode laser coherence length limits, the compensation range of existing fiber phase compensator is limited.At present
Single fiber phase compensator can only compensate the phase drift of maximum 25km length transmissions optical fiber.For the longer light of transmission range
Fibre, then need multiple fiber phase compensators to carry out segmented compensation.The prime cost of fiber phase compensator is that single longitudinal mode swashs
Light device, each fiber phase compensator are required to one single longitudinal mode laser of configuration so that when long-distance optical fiber transmits, for steady
The use cost of the fiber phase compensator of phase is higher.
Utility model content
In order to overcome long distance transmission optical fiber to carry out steady phase using multiple fiber phase compensators, cause use cost high
Shortcoming, the utility model provide a kind of cascaded optical fiber phase compensator, it uses upper level single longitudinal mode laser signal, itself is unworthy of
Single longitudinal mode laser is put, on each section of node of long distance transmission optical fiber, mutually cascade, the first wavelength division multiplexer is by the conjunction of access
Ripple signal solution wavelength-division, gained single longitudinal mode laser signal output to optical fiber splitter beam splitting are a branch of to be reflected by fiber reflector through light
Fine splitter and the first wavelength division multiplexer return to upper level Transmission Fibers；Another beam is sent into fibre optic interferometer through optoisolator.Light
The measuring arm of fine interferometer connects the transmission end of the second wavelength division multiplexer, and the test side of fibre optic interferometer connects through feedback control circuit
Fibre optic phase modulator is connect, the reflection end of first and second wavelength division multiplexer is connected, upper obtained by the first wavelength division multiplexer demultiplex point
The business optical signal of level-one is sent into the second wavelength division multiplexer and single longitudinal mode laser signal again multiplex；The public affairs of second wavelength division multiplexer
Outgoing traffic signal and the multiplex signal of single longitudinal mode laser signal is held to be accessed after fibre optic phase modulator carries out phase compensation altogether
This grade of Transmission Fibers.Each cascade fiber phase compensator eliminates each section of phase drift respectively, greatly reduces stabilized fiber and passes on from one to another
The equipment cost of defeated system.
The another object of the utility model is to provide the optical fiber transmission using the utility model cascaded optical fiber phase compensator
Transmission Fibers when Transmission Fibers are more than 25km, are divided into multistage of every segment length less than or equal to 25km by system, originating terminal
First fiber phase compensator is the common fiber phase compensator containing single longitudinal mode laser, is opened from second segment Transmission Fibers
The every section of Transmission Fibers head end that begins adds the cascaded optical fiber phase compensator an of the utility model, the tail end of final stage Transmission Fibers
Connection demultiplex divides fiber termination box.
A kind of cascaded optical fiber phase compensator provided by the utility model includes wavelength division multiplexer, optical fiber splitter, optical fiber
Speculum, fibre optic interferometer, fibre optic phase modulator and feedback control circuit.
First wavelength division multiplexer of the utility model has three ports, is respectively common port, transmission end, reflection end, its is saturating
End centre wavelength and single longitudinal mode laser consistent wavelength are penetrated, and does not include service signal wavelength in its transmission bandwidth；Upper level transmits
The common port of the first wavelength division multiplexer of intelligent acess is sent into the multiplex signal of single longitudinal mode laser signal and business optical signal；Multiplex is believed
Number by the first wavelength division multiplexer demultiplex point, gained single longitudinal mode laser signal is output to optical fiber splitter input terminal by its transmission end；
Optical fiber splitter is split single longitudinal mode laser signal to be exported by its straight-through end and coupled end respectively, and optical fiber splitter is led directly to
End connection fiber reflector, the part single longitudinal mode laser signal of fiber reflector reflection beam splitting is through optical fiber splitter and the first wavelength-division
Multiplexer returns to upper level Transmission Fibers；Input terminal of the coupled end of optical fiber splitter through optoisolator connection fibre optic interferometer,
It send another part single longitudinal mode laser signal of beam splitting as this grade of lasing light emitter optical signal into fibre optic interferometer.Fibre optic interferometer
Measuring arm connects the transmission end of the second wavelength division multiplexer, and the test side of fibre optic interferometer connects fiber phase through feedback control circuit
Modulator, the reflection end of the second wavelength division multiplexer are connected with the reflection end of the first wavelength division multiplexer, the first wavelength division multiplexer demultiplex
The business optical signal of upper level obtained by point is sent into the second wavelength division multiplexer and single longitudinal mode laser signal again multiplex；Second wavelength-division
The common port outgoing traffic signal of multiplexer accesses this level with the multiplex signal of single longitudinal mode laser signal through fibre optic phase modulator
Transmission Fibers.
The fibre optic interferometer includes the Michelson's interferometer based on 2 × 2 fiber couplers or 3 × 3 fiber couplers
With the interferometer fiber reflector as reference arm.
The feedback control circuit includes Photoelectric Detection module, phase drift identification module and phase compensation feedback control mould
Block.The optical signal that fibre optic interferometer exports is converted to electric signal by the Photoelectric Detection module of feedback control circuit, is sent into phase drift
Move phase drift of the identification module detection single longitudinal mode laser in Transmission Fibers transmitting procedure, phase compensation feedback control module root
The control voltage of fibre optic phase modulator is measured according to phase drift, incoming fiber optic phase-modulator controls it to single longitudinal mode laser
Signal carries out phase compensation.
The splitting ratio of the optical fiber splitter is (1/99) to (50/50), wherein big splitting ratio output termination fiber reflection
Mirror, small splitting ratio output termination optoisolator.
The optoisolator is used for the optical signal for isolating the output of local fiber interferometer, is allowed to that upper level transmission cannot be returned
Optical fiber.When the luminous power for inputting optoisolator is smaller can not meet fibre optic interferometer testing requirements, the optoisolator is replaced
For the image intensifer with isolator, the image intensifer operation wavelength covers single longitudinal mode laser signal wavelength.
The fibre optic phase modulator be one group or two groups based on Optical Fiber Winding emission type piezoelectric ceramics fiber phase
Modulator, or one group based on Optical Fiber Winding in the device of emission type piezoelectric ceramics and one group of continuously adjustable optical fiber delay line structure
Into fibre optic phase modulator.
Fibre-optic transmission system (FOTS) using the utility model cascaded optical fiber phase compensator is as follows, when the originating terminal of Transmission Fibers
During with the distance of receiving terminal more than 25km, Transmission Fibers are divided into n sections, and n >=2, the length of every section of Transmission Fibers is less than or equal to
25km；The fiber phase compensator that the head end of first segment Transmission Fibers, i.e. originating terminal are connect contains single longitudinal mode laser for common
Fiber phase compensator, since second segment Transmission Fibers, every section of Transmission Fibers head end connects the cascade an of the utility model
Fiber phase compensator, through n sections of Transmission Fibers and n-1 the utility model cascaded optical fiber phase compensator, final stage transmission
The demultiplex of optical fiber tail-end connection receiving terminal divides fiber termination box.The demultiplex divides fiber termination box to include receiving terminal wavelength division multiplexer and receiving terminal
Fiber reflector.The Transmission Fibers of the common port connection final stage of receiving terminal wavelength division multiplexer, the optical signal solution wavelength-division of reception
For business optical signal and single longitudinal mode laser signal, the business light that the reflection end output phase of receiving terminal wavelength division multiplexer is stablized is believed
Number.
Compared with prior art, the beneficial effect of a kind of cascaded optical fiber phase compensator of the utility model and fibre-optic transmission system (FOTS)
Fruit is：Long distance transmission optical fiber need to be only segmented using multiple cascaded optical fiber phase compensators, this cascaded optical fiber phase compensator is not
Containing single longitudinal mode laser, the cost of one platform is only the existing fiber phase compensator cost with single longitudinal mode laser
20% or so, the cost of fiber optic transmission system long haul is greatly lowered.
Brief description of the drawings
Fig. 1 is this cascaded optical fiber phase compensator example structure schematic diagram；
Fig. 2 is the fibre-optic transmission system (FOTS) example structure schematic diagram using this cascaded optical fiber phase compensator embodiment.
Embodiment
Cascaded optical fiber phase compensator embodiment
This cascaded optical fiber phase compensator embodiment is respectively public affairs as shown in Figure 1, the first wavelength division multiplexer has three ports
Common end, transmission end, reflection end, its transmission end centre wavelength and single longitudinal mode laser consistent wavelength, and do not include in its transmission bandwidth
Service signal wavelength；The common port that upper level Transmission Fibers access the first wavelength division multiplexer is sent into single longitudinal mode laser signal and business
The multiplex signal of optical signal；Multiplex signal is by the first wavelength division multiplexer demultiplex point, and gained single longitudinal mode laser signal is by its transmission end
It is output to optical fiber splitter input terminal；Optical fiber splitter is split single longitudinal mode laser signal respectively by its straight-through end and coupling
End output, the straight-through end connection fiber reflector of optical fiber splitter, the part single longitudinal mode laser letter of fiber reflector reflection beam splitting
Number return to upper level Transmission Fibers through optical fiber splitter and the first wavelength division multiplexer；The coupled end of optical fiber splitter is through optoisolator
The input terminal of fibre optic interferometer is connected, is sent into another part single longitudinal mode laser signal of beam splitting as this grade of lasing light emitter optical signal
Fibre optic interferometer.The measuring arm of fibre optic interferometer connects the transmission end of the second wavelength division multiplexer, the test side warp of fibre optic interferometer
Feedback control circuit connects the reflection end of fibre optic phase modulator, the reflection end of the second wavelength division multiplexer and the first wavelength division multiplexer
Connection, the business optical signal of the upper level of the first wavelength division multiplexer demultiplex point gained are sent into the second wavelength division multiplexer and are swashed with single longitudinal mode
Optical signal multiplex again；The common port outgoing traffic signal of second wavelength division multiplexer is passed through with the multiplex signal of single longitudinal mode laser signal
Fibre optic phase modulator accesses this grade of Transmission Fibers.
This example fibre optic interferometer is for the Michelson's interferometer based on 3 × 3 fiber couplers and as the interference with reference to arm
Instrument fiber reflector.
This example feedback control circuit includes Photoelectric Detection module, phase drift identification module and phase compensation feedback control mould
Block.The output optical signal of fibre optic interferometer is converted to electric signal by the Photoelectric Detection module of feedback control circuit, is sent into phase drift
Move phase drift of the identification module detection single longitudinal mode laser in Transmission Fibers transmitting procedure, phase compensation feedback control module root
The control voltage of fibre optic phase modulator is measured according to phase drift, incoming fiber optic phase-modulator controls it to single longitudinal mode laser
Signal carries out phase compensation.
The splitting ratio of this example optical fiber splitter is 1/99, wherein big splitting ratio output termination fiber reflector, small splitting ratio
Output termination optoisolator.
This example fibre optic phase modulator be two groups based on Optical Fiber Winding emission type piezoelectric ceramics fibre optic phase modulator.
When the luminous power for inputting optoisolator is smaller can not meet fibre optic interferometer testing requirements, this example optoisolator can
Replace with the image intensifer with isolator, image intensifer operation wavelength covering single longitudinal mode laser signal wavelength.
Using the fibre-optic transmission system (FOTS) embodiment of cascaded optical fiber phase compensator
This fibre-optic transmission system (FOTS) embodiment is passed as shown in Fig. 2, this example uses above-mentioned cascaded optical fiber phase compensator embodiment
When to lose the originating terminal of fibre and the distance of receiving terminal be 100km, this example Transmission Fibers are divided into 4 sections, the length of every section of Transmission Fibers
For 25km, the fiber phase compensator that the head end of first segment Transmission Fibers, i.e. originating terminal are connect contains single longitudinal mode laser for common
The fiber phase compensator of device, business optical signal SinEnter first after incoming fiber optic phase compensator, with single longitudinal mode laser multiplex
Section Transmission Fibers, since second segment Transmission Fibers, every section of Transmission Fibers head end connects the cascaded optical fiber phase an of the utility model
Position compensator, successively through first order cascaded optical fiber phase compensator, second segment Transmission Fibers, second level cascaded optical fiber phase compensation
Device, the 3rd section of Transmission Fibers, third level cascaded optical fiber phase compensator, the 4th section of Transmission Fibers, the 4th section of Transmission Fibers tail end
The demultiplex of connection receiving terminal divides fiber termination box.This example demultiplex divides fiber termination box to include receiving terminal wavelength division multiplexer and receiving terminal fiber reflection
Mirror.The common port of receiving terminal wavelength division multiplexer connects the 4th section of Transmission Fibers, and the optical signal demultiplex of reception is divided into business light letter
Number and single longitudinal mode laser signal, the business optical signal S that the reflection end output phase of receiving terminal wavelength division multiplexer is stablizedout。
Above-described embodiment, is only further described the purpose of this utility model, technical solution and beneficial effect
Specific case, the utility model are not limited to this.All any modifications made within the scope of disclosure of the utility model,
Equivalent substitution, improvement etc., are all contained within the scope of protection of the utility model.
Claims (8)
1. a kind of cascaded optical fiber phase compensator, including wavelength division multiplexer, optical fiber splitter, fiber reflector, fibre optic interferometer,
Fibre optic phase modulator and feedback control circuit；It is characterized in that：
First wavelength division multiplexer has three ports, is respectively common port, transmission end, reflection end, its transmission end centre wavelength and list
Longitudinal mode laser consistent wavelength, and do not include service signal wavelength in its transmission bandwidth；Upper level Transmission Fibers access the first wavelength-division
The common port of multiplexer is sent into the multiplex signal of single longitudinal mode laser signal and business optical signal；Multiplex signal is by the first wavelength-division multiplex
Device solution wavelength-division, gained single longitudinal mode laser signal are output to optical fiber splitter input terminal by its transmission end；Optical fiber splitter is to Dan Zong
Mould laser signal is split to be exported by its straight-through end and coupled end respectively, the straight-through end connection fiber reflection of optical fiber splitter
Mirror, the part single longitudinal mode laser signal of fiber reflector reflection beam splitting return to upper one through optical fiber splitter and the first wavelength division multiplexer
Level Transmission Fibers；Input terminal of the coupled end of optical fiber splitter through optoisolator connection fibre optic interferometer, by another portion of beam splitting
Single longitudinal mode laser signal is divided to be sent into fibre optic interferometer as this grade of lasing light emitter optical signal；The measuring arm connection second of fibre optic interferometer
The transmission end of wavelength division multiplexer, the test side of fibre optic interferometer connect fibre optic phase modulator, the second ripple through feedback control circuit
The reflection end of division multiplexer is connected with the reflection end of the first wavelength division multiplexer, the upper level of the first wavelength division multiplexer demultiplex point gained
Business optical signal be sent into the second wavelength division multiplexer and single longitudinal mode laser signal multiplex again；The common port of second wavelength division multiplexer
Outgoing traffic signal and the multiplex signal of single longitudinal mode laser signal access this grade of Transmission Fibers through fibre optic phase modulator.
2. cascaded optical fiber phase compensator according to claim 1, it is characterised in that：
The fibre optic interferometer includes Michelson's interferometer and work based on 2 × 2 fiber couplers or 3 × 3 fiber couplers
For the interferometer fiber reflector of reference arm.
3. cascaded optical fiber phase compensator according to claim 1, it is characterised in that：
The feedback control circuit includes Photoelectric Detection module, phase drift identification module and phase compensation feedback control module；
The output optical signal of fibre optic interferometer is converted to electric signal by the Photoelectric Detection module of feedback control circuit, is sent into phase drift and is known
Phase drift of the other module detection single longitudinal mode laser in Transmission Fibers transmitting procedure, phase compensation feedback control module is according to phase
Position drift value obtains the control voltage of fibre optic phase modulator, and incoming fiber optic phase-modulator controls it to single longitudinal mode laser signal
Carry out phase compensation.
4. cascaded optical fiber phase compensator according to claim 1, it is characterised in that：
The splitting ratio of the optical fiber splitter is (1/99) to (50/50), wherein big splitting ratio output termination fiber reflector, small
Splitting ratio output termination optoisolator.
5. cascaded optical fiber phase compensator according to claim 1, it is characterised in that：
When the luminous power for inputting optoisolator is smaller can not meet fibre optic interferometer testing requirements, the optoisolator replaces with
Image intensifer with isolator, the image intensifer operation wavelength cover single longitudinal mode laser signal wavelength.
6. cascaded optical fiber phase compensator according to claim 1, it is characterised in that：
The fibre optic phase modulator is one group or two groups and is modulated based on fiber phase of the Optical Fiber Winding in emission type piezoelectric ceramics
Device, or one group formed based on Optical Fiber Winding in the device of emission type piezoelectric ceramics and one group of continuously adjustable optical fiber delay line
Fibre optic phase modulator.
7. using the fibre-optic transmission system (FOTS) of the cascaded optical fiber phase compensator any one of claim 1 to 6, its feature exists
In：
When the originating terminal of Transmission Fibers and the distance of receiving terminal are more than 25km, Transmission Fibers are divided into n sections, n >=2, every section of transmission light
Fine length is less than or equal to 25km；The fiber phase compensator that the head end of first segment Transmission Fibers, i.e. originating terminal are connect is general
The logical fiber phase compensator containing single longitudinal mode laser, since second segment Transmission Fibers, every section of Transmission Fibers head end connects one
A cascaded optical fiber phase compensator, through n sections of Transmission Fibers and the n-1 cascaded optical fiber phase compensators, final stage
The demultiplex of Transmission Fibers tail end connection receiving terminal divides fiber termination box.
8. the fibre-optic transmission system (FOTS) of cascaded optical fiber phase compensator according to claim 7, it is characterised in that：
The demultiplex divides fiber termination box to include receiving terminal wavelength division multiplexer and receiving terminal fiber reflector；Receiving terminal wavelength division multiplexer
Common port connects the Transmission Fibers of afterbody, and the optical signal demultiplex of reception is divided into business optical signal and single longitudinal mode laser signal,
The business optical signal of the reflection end output of receiving terminal wavelength division multiplexer.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721168838.7U CN207283565U (en) | 2017-09-12 | 2017-09-12 | A kind of cascaded optical fiber phase compensator and fibre-optic transmission system (FOTS) |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721168838.7U CN207283565U (en) | 2017-09-12 | 2017-09-12 | A kind of cascaded optical fiber phase compensator and fibre-optic transmission system (FOTS) |
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| Publication Number | Publication Date |
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| CN207283565U true CN207283565U (en) | 2018-04-27 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201721168838.7U Withdrawn - After Issue CN207283565U (en) | 2017-09-12 | 2017-09-12 | A kind of cascaded optical fiber phase compensator and fibre-optic transmission system (FOTS) |
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| CN (1) | CN207283565U (en) |
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- 2017-09-12 CN CN201721168838.7U patent/CN207283565U/en not_active Withdrawn - After Issue
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Granted publication date: 20180427 Effective date of abandoning: 20230523 |