CN106785833A - A kind of erbium-doped fiber amplifier of power limiting gain controllable - Google Patents
A kind of erbium-doped fiber amplifier of power limiting gain controllable Download PDFInfo
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- CN106785833A CN106785833A CN201611110860.6A CN201611110860A CN106785833A CN 106785833 A CN106785833 A CN 106785833A CN 201611110860 A CN201611110860 A CN 201611110860A CN 106785833 A CN106785833 A CN 106785833A
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- Prior art keywords
- doped fiber
- multiplexer
- isolator
- erbium
- optical splitter
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/06—Construction or shape of active medium
- H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
- H01S3/067—Fibre lasers
- H01S3/06754—Fibre amplifiers
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/06—Construction or shape of active medium
- H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
- H01S3/067—Fibre lasers
- H01S3/06754—Fibre amplifiers
- H01S3/06758—Tandem amplifiers
Abstract
The present invention discloses a kind of erbium-doped fiber amplifier of power limiting gain controllable, including the first isolator, the first optical splitter, the first multiplexer, the first Er-doped fiber, the second multiplexer, the second Er-doped fiber, the second isolator, the second optical splitter, controller, the first photodetector and the second photodetector, the present invention solves big and gain flatness difference the technical problem of noise coefficient in the prior art.
Description
Technical field
The present invention relates to technical field of photo communication, more particularly to a kind of Erbium-doped fiber amplifier of power limiting gain controllable
Device.
Background technology
The general principle of erbium-doped fiber amplifier be using the Er3+ ions in Er-doped fiber under the exciting of pump light shape
Into population inversion, stimulated radiation light amplification is realized under the induction of flashlight.Pumping source is generally using 980nm's and 1480nm
Laser.The metastable state and ground state of Er3+ ions have certain width, make the enlarge-effect of EDFA and have a wavelength range, its
Representative value is in 1530-1570nm.
However, when Er3+ ions are in metastable state, in addition to it there is stimulated radiation and excited absorption, also to produce spontaneous
Radiation, i.e. Er3+ the ions stop of short duration in metastable state do not have had a chance to be interacted with photon, will spontaneously from metastable state
Transit to ground state and launch the photon of 1550nm wave bands, this photon is different from flashlight, it constitutes the noise of EDFA.In reality
In the system of border, due to spontaneous radiation and the presence of optical noise, flashlight is not only propagated and amplified to erbium-doped fiber amplifier, while
Also spontaneous radiation is exaggerated, this non-signal light propagated in a fiber and amplify is called ASE light.
Although the power very little of ASE, the frequency that it is covered is very wide, can consume the pump power of a part, Er Qieyou
Two directions of propagation (forward and reverse) are so that the multiplication factor of influence signal.Especially the ASE light of reverse transfer is by anti-
To amplification after, pass to quite big during the input of erbium-doped fiber amplifier, and flashlight now is then very weak, this
Sample will directly result in the deterioration of noise coefficient and signal gain.
With continuing to develop for the communication technology, the communication of broadband and high speed is increasingly subject to the extensive concern of society.Especially
The huge potential broadband that the DWDM (dense wave division multipurpose) of optical communication field brings, broadband transmission extremely people attract attention.From er-doped light
Since fiber amplifier commercialization, it certainly plays vital effect in all optical communication.It mixes 1.55um wave bands
Doped fiber amplifier (EDFA) can effectively compensate for fiber transmission attenuation and shunt loss.However, because EDFA exists in itself
The gain spreading characteristic of gain unevenness and uniform saturation, this power difference is gradually accumulated along transmission path, can be made
Into some signal power high concentrations, cause fiber nonlinear effect (such as：Self-phase modulation SPM, Cross-phase Modulation XPM
Deng), and some channel powers are too small, beyond receiver sensitivity scope.Therefore, the unbalanced eventually serious evil of channel power
The performance of change system.The unbalanced phenomenon of interchannel power occurs in signal amplification process.
In order to solve this problem, there has been proposed the technical side that various utilization erbium-doped fiber amplifiers realize power limiting
Case, makes the different signal of power identical by power output after amplification.Wherein, Oliver C.Graydon etc. propose a kind of insertion
The mechanism of differential loss realizes power limiting, relatively simple for structure.But, the program is using the fiber turns for being coiled into certain diameter
To realize the differential loss to pump light and flashlight, reliability is poor.
Traditional unistage type erbium-doped fiber amplifier light path：Flashlight and pump light are coupled into er-doped light by coupler
Fibre, the length of Er-doped fiber is typically issued to maximization by theoretical modeling in given pumping efficiency.Because Er-doped fiber is put
Stimulated radiation and spontaneous radiation are there is simultaneously in big device, spontaneous radiation is constantly amplified during propagation, to output
Obvious noise can be turned into during end, so as to influence the signal to noise ratio of output signal.
The content of the invention
It is an object of the invention to provide a kind of erbium-doped fiber amplifier of power limiting gain controllable, solve in the prior art
Big and gain flatness difference the technical problem of noise coefficient；
The technical scheme that the present invention solves above-mentioned technical problem is as follows：
A kind of erbium-doped fiber amplifier of power limiting gain controllable, including the first isolator, the first optical splitter, first answer
With device, the first Er-doped fiber, the second multiplexer, the second Er-doped fiber, the second isolator, the second optical splitter, controller, the first light
Detector and the second photodetector；
The input optical signal enters the first Er-doped fiber by the first isolator, the first optical splitter and the first multiplexer,
The output end of input first optical splitter of termination of first photodetector；
The input of the controller connects the first photo-detector and the second photo-detector, the output of the controller respectively
Hold the input that the first multiplexer is connected through pump laser；
The output end of first Er-doped fiber connects the second multiplexer, the output end connection second of second multiplexer
Er-doped fiber；
Second Er-doped fiber is sequentially connected second isolator and the second optical splitter.
On the basis of above-mentioned technical proposal, the present invention can also do following improvement：
Further, it also includes differential loss ring, and the differential loss ring is arranged on the first Er-doped fiber, the second er-doped light
Between fibre, and differential loss ring is in parallel with the second multiplexer.
Further, the differential loss ring includes adjustable attenuator and the 3rd isolator, the adjustable attenuator and the 3rd
Isolator is connected, and adjustable attenuator is connected with the controller,
Further, it also includes back-ray detection device, and the back-ray detection device connects the second optical splitter, controller respectively.
Beneficial effects of the present invention：
1. the present invention is separated using the Er-doped fiber of two sections of cascade optimizations by isolator, it is allowed to which flashlight is logical from forward direction
Cross, and the ASE noises of backpropagation cannot be by leading portion optical fiber, so that reversely ASE noises will not consume pump laser
Power and influence signal improve signal gain amplifier in the amplification of leading portion.
2. the present invention is not amplified due to reverse ASE noises in first paragraph Er-doped fiber, can reduce the first order
Noise coefficient, because in multilevel system, the total noise coefficient of system is mainly to be influenceed by first order noise coefficient, so can
To reduce total noise coefficient.
3. the present invention, by changing the loss of adjustable attenuator, can be adjusted using adjustable attenuator is placed in circuit
The average reversion level of Er-doped fiber, further changes the gain tilt in EDFA gain spectrals；
4. the present invention is turned using the first photo-detector, the second photo-detector collection signal input, power output by A/D
Signal is converted into data signal, via controller treatment, control pump laser output, to reach fine setting pump by parallel operation by analog quantity
The pump power of Pu laser；
5. the present invention does light echo detection using back-ray detection device from output end, and the optical fiber behind output end once occurs disconnected
Road, local erbium-doped fiber amplifier can detect stronger back wave, so that microprocessor judgement and time disconnected pumping swash
Light device, it is to avoid injure other optical devices and alarm.
Brief description of the drawings
In order to illustrate more clearly of the specific embodiment of the invention or technical scheme of the prior art, below will be to specific
The accompanying drawing to be used needed for implementation method or description of the prior art is briefly described, it should be apparent that, in describing below
Accompanying drawing is some embodiments of the present invention, for those of ordinary skill in the art, before creative work is not paid
Put, other accompanying drawings can also be obtained according to these accompanying drawings.
Fig. 1 is a kind of structure of the erbium-doped fiber amplifier of the power limiting gain controllable described in the specific embodiment of the invention
Schematic diagram；
Fig. 2 is a kind of pumping of the erbium-doped fiber amplifier of the power limiting gain controllable described in the specific embodiment of the invention
Light and signal light power strangulation curve.
In accompanying drawing, the list of parts representated by each label is as follows：
1st, the first isolator；2nd, the first optical splitter；3rd, the first multiplexer；4th, the first Er-doped fiber；5th, the second multiplexer；6、
Second Er-doped fiber；7th, the second isolator；8th, the second optical splitter；9th, controller；10th, the first photodetector；11st, the second light detection
Device；12nd, pump laser；13rd, differential loss ring；14th, adjustable attenuator；15th, the 3rd isolator；16th, back-ray detection device；17、
First port；18th, second port；19th, the 3rd port；20th, the 4th port.
Specific embodiment
Principle of the invention and feature are described below in conjunction with accompanying drawing, example is served only for explaining the present invention, and
It is non-for limiting the scope of the present invention.
Technical scheme is clearly and completely described below in conjunction with accompanying drawing, it is clear that described implementation
Example is a part of embodiment of the invention, rather than whole embodiments.Based on the embodiment in the present invention, ordinary skill
The every other embodiment that personnel are obtained under the premise of creative work is not made, belongs to the scope of protection of the invention.
In the description of the invention, it is necessary to illustrate, term " first " and " second " are only used for describing purpose, and can not
It is interpreted as indicating or implying relative importance.
In the description of the invention, it is necessary to illustrate, unless otherwise clearly defined and limited, term " installation ", " phase
Company ", " connection " should be interpreted broadly, for example, it may be being fixedly connected, or being detachably connected, or be integrally connected；Can
Being to mechanically connect, or electrically connect；Can be joined directly together, it is also possible to be indirectly connected to by intermediary, Ke Yishi
Two connections of element internal.For the ordinary skill in the art, with concrete condition above-mentioned term can be understood at this
Concrete meaning in invention.
Embodiment：
A kind of erbium-doped fiber amplifier of power limiting gain controllable, including the first isolator 1, the first optical splitter 2, first
Multiplexer 3, the first Er-doped fiber 4, the second multiplexer 5, the second Er-doped fiber 6, the second isolator 7, the second optical splitter 8, control
Device 9, the first photodetector 10 and the second photodetector 11；
The input optical signal enters the first er-doped light by the first isolator 1, the first optical splitter 2 and the first multiplexer 3
Fine 4, the output end of input first optical splitter 2 of termination of first photodetector 10；
The input of the controller 9 connects the first photo-detector 10 and the second photo-detector 11, the controller 9 respectively
Output end through pump laser 12 connect the first multiplexer 3 input；
The output end of first Er-doped fiber 4 connects the second multiplexer 5, the output end connection of second multiplexer 5
Second Er-doped fiber 6；
Second Er-doped fiber 6 is sequentially connected the optical splitter 8 of second isolator 7 and second.
Wherein, it also includes differential loss ring 13, and the differential loss ring 13 is arranged on the first Er-doped fiber 4, second mixes
Between erbium optical fiber 6, and differential loss ring 13 is in parallel with the second multiplexer 5.
Further, the differential loss ring 13 includes the isolator 15 of adjustable attenuator 14 and the 3rd, the adjustable attenuator
14 and the 3rd isolator 15 connect, and adjustable attenuator 14 is connected with the controller 15,
Wherein, it also includes back-ray detection device 16, and the back-ray detection device 16 connects the second optical splitter 8, controller respectively
9。
Operation principle of the invention：
Optical signal is by after first paragraph Er-doped fiber 4, the 3rd end being coupled to from the first port 17 of differential loss ring 13
Mouthfuls 19, by after optoisolator 6 and variable attenuator 7, and it is coupled to the 4th port 20 from second port 18 and enters back into second segment
In Er-doped fiber 6.And the direct first port 17 from differential loss ring 13 of residual pump light exported from first paragraph Er-doped fiber 4
The 4th port 20 is coupled to, almost without added losses；
The electric signal of the light of the first photodetector 10, the second photodetector 11 and back-ray detection device 16 detection all sends into control
Device 9, the controller 9 controls the work of pump laser 12 accordingly, the laser power of pump laser 12 by the first multiplexer 3 with
First paragraph Er-doped fiber 4 is input into after signal optical coupling.
Wherein the major function of controller 9 includes photo-detector collecting unit, pump laser power driver element, microprocessor
Device (MCU) and control keyboard and display, the function of its gain control are implemented as follows：First photo-detector 10 and the second light are visited
Survey device 11 and gather the instant laser power of input, output signal respectively, and export corresponding electric signal to controller 9；
(1) the first photo-detector 10 and the second photo-detector 11 are gathered photo-detector collecting unit the luminous intensity electricity of input
Signal is converted into data signal by analog quantity；
(2) processed through Micro-processor MCV, be calculated the gain of real-time signal.
(3) the instant gain of signal is compared with default target gain, controller 9 goes out pump according to certain step size computation
The increase or reduction amount of the Injection Current of Pu laser 12, analog signal output to pump is converted into by D/A converter by this result
Pu laser 12, to reach the power of fine setting pump laser；
(4) the real-time signal gain after adjustment is measured according to the method in the step of (1)-(3), Step d is repeated, until pumping
The instant gain of signal of laser 12 reaches target gain.
According to theoretical it is experimentally confirmed that Fig. 2 gives pump light and signal light power under structure shown in Fig. 1 that simulation is calculated
Strangulation curve.Characteristic when solid line and dotted line represent input as -20dB and 0dB respectively.It can be seen that, by first paragraph er-doped light
After fine 4, two signals are amplified, but -20dB signal gains are more much smaller than the gain that 0dB is obtained.Continue through difference
Enter after second segment Er-doped fiber 6 after the decay identical dB numerical value of different consumptive loop 5, be input into the signal for -20dB in residual pump
Continue to be amplified under the light stimulus of Pu, and be input into as the signal second segment Er-doped fiber 6 of 0dB slightly has absorption to it.As a result, two
Input signal of different sizes merges on same power points in the output end of second segment Er-doped fiber 6.From -20dB to 0dB
Between any size signal corresponding power change curve should between this two curves, therefore, -20dB to 0dB 20dB
Power limiting is realized in dynamic range.
Finally it should be noted that：Various embodiments above is merely illustrative of the technical solution of the present invention, rather than its limitations；To the greatest extent
Pipe has been described in detail with reference to foregoing embodiments to the present invention, it will be understood by those within the art that：Its according to
The technical scheme described in foregoing embodiments can so be modified, or which part or all technical characteristic are entered
Row equivalent；And these modifications or replacement, the essence of appropriate technical solution is departed from various embodiments of the present invention technology
The scope of scheme.
Claims (4)
1. a kind of erbium-doped fiber amplifier of power limiting gain controllable, it is characterised in that：Including the first isolator, the first light splitting
Device, the first multiplexer, the first Er-doped fiber, the second multiplexer, the second Er-doped fiber, the second isolator, the second optical splitter, control
Device, the first photodetector and the second photodetector；
The input optical signal enters the first Er-doped fiber by the first isolator, the first optical splitter and the first multiplexer, described
The output end of input first optical splitter of termination of the first photodetector；
The input of the controller connects the first photo-detector and the second photo-detector, the output end warp of the controller respectively
Pump laser connects the input of the first multiplexer；
The output end of first Er-doped fiber connects the second multiplexer, and the output end of second multiplexer connects the second er-doped
Optical fiber；
Second Er-doped fiber is sequentially connected second isolator and the second optical splitter.
2. the erbium-doped fiber amplifier of a kind of power limiting gain controllable according to claim 1, it is characterised in that：It is also
Including differential loss ring, the differential loss ring is arranged between the first Er-doped fiber, the second Er-doped fiber, and differential loss ring
It is in parallel with the second multiplexer.
3. the erbium-doped fiber amplifier of a kind of power limiting gain controllable according to claim 2, it is characterised in that described
Differential loss ring includes adjustable attenuator and the 3rd isolator, and the adjustable attenuator and the 3rd isolator are connected, and adjustable declines
Subtract device to be connected with the controller.
4. the erbium-doped fiber amplifier of a kind of power limiting gain controllable according to claim 3, it is characterised in that it is also
Including back-ray detection device, the back-ray detection device connects the second optical splitter, controller respectively.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201611110860.6A CN106785833B (en) | 2016-12-06 | 2016-12-06 | A kind of erbium-doped fiber amplifier of power limiting gain controllable |
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| CN201611110860.6A CN106785833B (en) | 2016-12-06 | 2016-12-06 | A kind of erbium-doped fiber amplifier of power limiting gain controllable |
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| CN106785833B CN106785833B (en) | 2019-04-23 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109038189A (en) * | 2018-07-27 | 2018-12-18 | 武汉光迅科技股份有限公司 | A kind of double 980 pump lasers in EDFA are to pump configuration |
| CN114156722A (en) * | 2021-12-15 | 2022-03-08 | 无锡市德科立光电子技术股份有限公司 | VOA control method in variable gain erbium-doped fiber amplifier |
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| US5764406A (en) * | 1996-10-01 | 1998-06-09 | Corning Incorporated | Hydrid optical amplifier having improved dynamic gain tilt |
| CN1469180A (en) * | 2002-07-18 | 2004-01-21 | 华为技术有限公司 | Low-noise variable-gain optical amplifier |
| CN101217319A (en) * | 2008-01-10 | 2008-07-09 | 复旦大学 | A gain controllable two-segment erbium-doped optical fiber amplifier |
| CN105656561A (en) * | 2016-03-21 | 2016-06-08 | 吉林大学 | Double-ring feedback gain flattening erbium-doped optical fiber amplifier |
-
2016
- 2016-12-06 CN CN201611110860.6A patent/CN106785833B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5764406A (en) * | 1996-10-01 | 1998-06-09 | Corning Incorporated | Hydrid optical amplifier having improved dynamic gain tilt |
| CN1469180A (en) * | 2002-07-18 | 2004-01-21 | 华为技术有限公司 | Low-noise variable-gain optical amplifier |
| CN101217319A (en) * | 2008-01-10 | 2008-07-09 | 复旦大学 | A gain controllable two-segment erbium-doped optical fiber amplifier |
| CN105656561A (en) * | 2016-03-21 | 2016-06-08 | 吉林大学 | Double-ring feedback gain flattening erbium-doped optical fiber amplifier |
Non-Patent Citations (1)
| Title |
|---|
| OLIVER C.GRAYDON ET AL: "Erbium-doped-fiber optical limiting amplifiers", 《JOURNAL OF LIGHTWAVE TECHNOLOGY》 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109038189A (en) * | 2018-07-27 | 2018-12-18 | 武汉光迅科技股份有限公司 | A kind of double 980 pump lasers in EDFA are to pump configuration |
| CN109038189B (en) * | 2018-07-27 | 2019-12-31 | 武汉光迅科技股份有限公司 | Double 980 pump laser pair pump structure for EDFA |
| WO2020019661A1 (en) * | 2018-07-27 | 2020-01-30 | 武汉光迅科技股份有限公司 | Opposing pump structure for twin 980-nm pump lasers in edfa |
| CN114156722A (en) * | 2021-12-15 | 2022-03-08 | 无锡市德科立光电子技术股份有限公司 | VOA control method in variable gain erbium-doped fiber amplifier |
| CN114156722B (en) * | 2021-12-15 | 2023-12-22 | 无锡市德科立光电子技术股份有限公司 | Control method of VOA in variable gain erbium-doped fiber amplifier |
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Denomination of invention: An erbium-doped fiber amplifier with controllable power clamp gain Effective date of registration: 20201126 Granted publication date: 20190423 Pledgee: Jiangsu Credit Financing Guarantee Co.,Ltd. Pledgor: JIANGSU HIMARK HI-TECH Co.,Ltd. Registration number: Y2020980008539 |
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