CN1556438A - Gain dsplacement type thulium aduterated optical fiber amplifier using spontaneous radiation light source as auxiliary pumping - Google Patents
Gain dsplacement type thulium aduterated optical fiber amplifier using spontaneous radiation light source as auxiliary pumping Download PDFInfo
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- CN1556438A CN1556438A CNA2003101116844A CN200310111684A CN1556438A CN 1556438 A CN1556438 A CN 1556438A CN A2003101116844 A CNA2003101116844 A CN A2003101116844A CN 200310111684 A CN200310111684 A CN 200310111684A CN 1556438 A CN1556438 A CN 1556438A
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- pumping
- band
- pump
- fiber amplifier
- auxiliary
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- 238000005086 pumping Methods 0.000 title claims abstract description 85
- 230000002269 spontaneous effect Effects 0.000 title claims abstract description 7
- 229910052775 Thulium Inorganic materials 0.000 title claims description 11
- FRNOGLGSGLTDKL-UHFFFAOYSA-N thulium atom Chemical compound [Tm] FRNOGLGSGLTDKL-UHFFFAOYSA-N 0.000 title claims description 10
- 230000005855 radiation Effects 0.000 title claims description 7
- 239000013307 optical fiber Substances 0.000 title abstract description 8
- 239000000835 fiber Substances 0.000 claims abstract description 25
- 238000010168 coupling process Methods 0.000 claims description 8
- 238000005859 coupling reaction Methods 0.000 claims description 8
- 230000007246 mechanism Effects 0.000 claims description 8
- 230000008878 coupling Effects 0.000 claims description 7
- 238000013461 design Methods 0.000 abstract description 6
- 239000004065 semiconductor Substances 0.000 abstract description 5
- 229910052691 Erbium Inorganic materials 0.000 abstract description 4
- UYAHIZSMUZPPFV-UHFFFAOYSA-N erbium Chemical compound [Er] UYAHIZSMUZPPFV-UHFFFAOYSA-N 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 238000012423 maintenance Methods 0.000 abstract 1
- 230000003321 amplification Effects 0.000 description 6
- 238000003199 nucleic acid amplification method Methods 0.000 description 6
- 230000005283 ground state Effects 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 230000009977 dual effect Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 230000005281 excited state Effects 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000002708 enhancing effect Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000003595 spectral effect Effects 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- AATUHDXSJTXIHB-UHFFFAOYSA-K trifluorothulium Chemical compound F[Tm](F)F AATUHDXSJTXIHB-UHFFFAOYSA-K 0.000 description 2
- 238000001069 Raman spectroscopy Methods 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000000862 absorption spectrum Methods 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000002860 competitive effect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
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Abstract
The invention discloses a gain shifting thulium-doped optical-fiber amplifier using spontaneous radiant light source as an auxiliary pump, relating to an optical fiber amplifier and concretely the selection of pumping wavelength and the design of light path of a gain shifting thulium-doped optical-fiber amplifier. It mainly adds C-band ASE auxiliary pump to the 1400mm (1050) pump to improve the property of this amplifier; the pumping source adopts the ASE output light of the Erbium-doped optical fiber as a pump, and is composed of 980nm or 1480nm semiconductor pumping laser and 11m plus or minus 2m Erbium fiber, and concretely composed of a pump, an Erbium -doped optical fiber, a coupler, a reflector and an output pump; it enhances the property of the products and at the same time, can effectively reduce fabrication cost of the products and maintenance expensed of the system.
Description
Technical field
The present invention relates to a kind of fiber amplifier; Specifically, the pumping wavelength that relates to the gain dsplacement type thulium doped fiber amplifier is selected and light path design.
Background technology
At present, optical transmission system develops towards the direction of high capacity, higher rate more; The research of corresponding light amplifier also extended to short-wave band (S-Band, 1450-1520nm) and the overlength wave band (UL-Band, 1610-1670nm).Wherein, in the S-Band signal have low-loss (＜0.25dB/km), the characteristics of low chromatic dispersion, therefore caused people's extensive attention.
At present, realize that the fiber amplifier that S-Band amplifies mainly contains 3 kinds: thulium doped fiber amplifier (TDFA), Erbium-Doped Fiber Amplifier (EDFA) (EDFA) and fiber Raman amplifier (FRA).The intrinsic transmitted bandwidth of erbium ion is that (C-Band 1530-1560nm), needs the waveguiding structure of EDFA is rethought when therefore doing the S-Band design common wave band; FRA can realize the broadband amplification, but pump conversion efficiency is lower, and cost is higher.
TDFA gains high, and the big and acceptable noise figure of output power is the preferred option that realizes that S-band amplifies.TDFA is divided into two kinds according to gain band: (TDFA, amplification range is 1455-1485nm to the plain edition thulium doped fiber amplifier, i.e. S
+-band) and gain dsplacement type thulium doped fiber amplifier (GS-TDFA, amplification range is 1480-1510nm, i.e. S-band).Because silica-based optical fibers is lower than S in chromatic dispersion and the loss of S-band
+-band, so GS-TDFA has become the main direction of studying of present S-band amplifier.
The pumping array mode that realizes GS-TDFA has a lot.Wherein, 1400nm+1560nm is a kind of main application mode.At present, the manufacture craft of 1400nm pump laser is very ripe; But the 1560nm pump laser is also relatively deficienter on market, has limited the practical application of this pumping combination.
Summary of the invention
Find in the experiment: compare with only using the 1400nm pumping, adopt the S-band image intensifer of 1400nm and 1560nm combination pumping can obtain better noisiness; The TDFA that does auxiliary pumping with C-Band ASE (spontaneous radiation) light source can remedy this defective; Realize that GS-TDFA has a variety of pumping array modes.In order to obtain high-gain, low noise characteristic, adopt the combination of new pumping wavelength, when obtained performance is good, also simplified the design of light channel structure.Therefore purpose of the present invention is exactly the deficiency that remedies high-power 1560nm semiconductor pump laser scarcity on the market, provides a kind of with the gain dsplacement type thulium doped fiber amplifier (being a kind of with the GS-TDFA of ASE light source for auxiliary pumping) of spontaneous radiation light source for auxiliary pumping.
The object of the present invention is achieved like this: by using the auxiliary pumping of C-band ASE light source, improve four-level Tm
3+The ground state of system absorbs, thereby improves the counter-rotating degree of particle, improves the noise figure of GS-TDFA.When enhancing product performance, also reduced the manufacturing cost of product.
(1) theoretical analysis
Tm
3+Be a four-level system, level structure figure sees Fig. 1.
Wherein
3H
4→
3F
4The stimulated radiation transition produce S-band and amplify.
When the dual wavelength pumping, the 1560nm pumping makes
3H
6→
3F
4, then 1400 nm pumpings make
3F
4→
3H
1The energy of regulating two pumping wavelengths is with control Tm
3+In the distribution of each energy level, the amplification bandwidth of TDFA is by S
+-band moves on to S-band.
In conjunction with Tm
3+Energy level diagram, to expect that as can be seen (1450 ~ 1500nm) signals output, generalized case will realize in two steps: the first step absorbs (GSA) by ground state and makes Tm for the S-band of amplification
3+Transit to
3F
4In second step, (ESA) makes by excited state absorption
3F
4On Tm
3+Transit to higher excited state
3H
4, the population upset of energy level about realizing (
3H
4-
3F
4).
At present, the pumping wavelength array mode of realization S-band TDFA has a lot.Different pumping wavelengths, different light channel structures may cause different pump conversion efficiencies and noisiness.The Tm that mixes when the TDF fibre core
3+During the about 6000ppm of concentration, since the doping content height, Tm
3+Lean on very closely.Be in
3H
4The Tm of energy level
3+In spontaneous radiation extremely
3F
4Process in can be transferred to ground state Tm adjacent thereto to energy
3+, and the Tm of ground state
3+Because absorbing energy is excited to
3F
4Energy level, promptly so-called cross relaxation process.Cross relaxation makes and is in
3F
4The population of energy level increases, and low population inversion attitude must make gain spectral move to the long wave direction in formation.When using high doping optical fiber, mainly adopt 1400nm (1047nm) main pump Pu to add the array mode of the auxiliary pumping of 1560nm.
Find in the test: when the service pump pumping wavelength changed between 1540nm-1560nm, the performance of GS-TDFA did not have obvious variation; Simultaneously, near the semiconductor pump laser technology the present 1560nm is ripe not enough.Therefore, we have designed and have utilized the GS-TDFA of C-band ASE light source as auxiliary pumping under above guide of theory.
(2) concrete scheme
Usually the light channel structure of single step arrangement S-Band GS-TDFA is made up of input signal A, output signal B, optoisolator 1, signal/pumping wave multiplexer 2, thulium doped fiber 3, pumping wave multiplexer 4, main pump Pu 5, auxiliary pumping 6 as shown in Figure 3.
Here 1400nm of Cai Yonging and 1560nm pump laser all are to adopt pump mode in the same way, also can adopt the mode of backward pumping or two directional pump certainly.
When the wavelength of auxiliary pumping 6 changed between 1540nm-1560nm, the performance of GS-TDFA did not have obvious variation.
Technical scheme of the present invention is:
1. C-Band ASE pumping source has adopted the ASE output light of Er-doped fiber as pumping.Its typical structure is made of the erbium fibre of a 980nm or 1480nm semiconductor pump laser and appropriate length, and concrete structure is made up of pumping 8, Er-doped fiber 9, coupling mechanism 10, catoptron 11, output pumping 12 as shown in Figure 4.
2. the present invention adopts the auxiliary pumping 6 of 1560nm in auxiliary pumping source 7 alternate figures 3 of C-Band ASE shown in Figure 4, thereby obtains light channel structure as shown in Figure 5.
Owing to substitute 1560nm pumping 6 with the auxiliary pumping source 7 of C-Band ASE, make
3F
4On Tm
3+Transit to higher excited state
3H
4, the population upset of energy level about realizing (
3H
1-
3F
4).
In design in the past, the 1560nm pump laser can realize that this can cause complicated light channel structure and expensive cost by the mode of fiber laser or EDFA amplification 1560nm signal.The C-Band ASE that adopts the present invention to propose assists the GS-TDFA of pumping configuration will make product more competitive.
Simultaneously, compare with the auxiliary pumping of 1560nm, the performance of the auxiliary pumping pair amplifier of C-Band ASE can not cause damage, under proper condition, also may improve to some extent aspect noisiness.
The performance of test different light paths structure GS-TDFA obtains output power spectrum and noise spectrum referring to Fig. 6.
Having adopted doping content in the test is the fluoride thulium doped fiber of 6500ppm (By weight), and length is 5m.
Wherein: dotted line is represented the 1425nm pumping of 486mW and the 1560nm pumping of 20.7dBm; Solid line is represented the 1425nm pumping of 486mW and the C-band ASE pumping of 17.95dB.
The present invention has the following advantages and good effect:
1) the auxiliary pumping source of C-Band ASE adopts very ripe 1480nm semiconductor pump laser technology, makes simple and reliable.
2) light channel structure of the present invention is simple, is easy to realize, when enhancing product performance, can effectively reduce cost.
3) can significantly improve the noise figure characteristic of GS-TDFA.
Description of drawings
Fig. 1 is Tm
3+Level structure figure; Pumping wavelength correspondence shown in the figure Tm
3+The peak value of absorption spectra.
Fig. 2 is the energy level diagram of dual wavelength pumping TDFA.
Fig. 3 makes up the light channel structure figure of the single step arrangement GS-TDFA of pumping source for adopting 1400nm and 1560nm.
Fig. 4 is a C-Band ASE service pump source light path structural drawing.
Fig. 5 makes up the light channel structure figure of the single step arrangement GS-TDFA of pumping source for adopting 1400nm and C-Band ASE.
Fig. 6 is for using dual wavelength pumping source 1420nm+1560nm or 1420nm+C-band ASE, the gain spectral of the single step arrangement GS-TDFA of measurement and noise figure figure.
Wherein:
The A-input signal;
The B-output signal;
The 1-optoisolator;
2-signal/pumping wave multiplexer;
3-thulium doped fiber, i.e. fluoride thulium doped fiber;
4-pumping wave multiplexer;
5-main pump Pu, or be the main pumping band of 1400nm (1400nm-1420nm), or be 1050nm main pump Pu;
6-assists pumping, and a kind of 1560nm assists pumping;
7-C-Band ASE assists pumping source;
8-pumping, or 980nm pumping, or 1480nm pumping
The 9-Er-doped fiber, its length is: 11m ± 2m
The 10-coupling mechanism, or be the 980nm/1550nm coupling mechanism, or be the 1480nm/1550nm coupling mechanism;
The 11-catoptron;
12-exports pumping.
Embodiment
As Fig. 3, in the light channel structure of single step arrangement GS-TDFA, substitute the auxiliary pumping 6 of 1560nm with the auxiliary pumping source 7 of C-band ASE and obtain novel GS-TDFA combination pumping shown in Figure 5.
Under identical pump mode (being pumping in the same way) and pump power condition, application drawing 3 and light channel structure shown in Figure 5 carry out GS-TDFA test respectively, gained the results are shown in Figure 6.Wherein: dotted line is represented the 1425nm pumping of 486mW and the 1560nm pumping of 117mW; Solid line is represented the 1425nm pumping of 486mW and the C-band ASE pumping of 62mW.By comparing as seen, under the felicity condition, for the 1560nm pumping, the auxiliary pumping of C-bandASE light source helps further reducing the noise figure of GS-TDFA.
Simultaneously, we have also carried out the experiment of reverse configuration to auxiliary pumping.Experiment finds that the auxiliary pumping function of its effect and 1560nm is suitable.
Through a large amount of experimental verifications, design proposal of the present invention is practicable.
Claims (1)
1, a kind of with the gain dsplacement type thulium doped fiber amplifier of spontaneous radiation light source for auxiliary pumping, the light channel structure that comprises general purpose single level structure S-Band GS-TDFA is made up of input signal (A), output signal (B), optoisolator (1), signal/pumping wave multiplexer (2), thulium doped fiber (3), pumping wave multiplexer (4), main pump Pu (5), auxiliary pumping (6); Comprise that also C-Band ASE assists pumping source (7), form by pumping (8), Er-doped fiber (9), coupling mechanism (10), catoptron (11), output pumping (12); It is characterized in that:
Substitute the auxiliary pumping (6) of 1560nm with the auxiliary pumping source (7) of C-Band ASE;
Pumping (8) or be the 980nm pumping, or be the 1480nm pumping;
Coupling mechanism (10) or be the 980nm/1550nm coupling mechanism, or be the 1480nm/1550nm coupling mechanism;
The length of Er-doped fiber (9) is: 11m+2m
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2003101116844A CN1317600C (en) | 2003-12-30 | 2003-12-30 | Gain dsplacement type thulium aduterated optical fiber amplifier using spontaneous radiation light source as auxiliary pumping |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2003101116844A CN1317600C (en) | 2003-12-30 | 2003-12-30 | Gain dsplacement type thulium aduterated optical fiber amplifier using spontaneous radiation light source as auxiliary pumping |
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| Publication Number | Publication Date |
|---|---|
| CN1556438A true CN1556438A (en) | 2004-12-22 |
| CN1317600C CN1317600C (en) | 2007-05-23 |
Family
ID=34336267
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|---|---|---|---|
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010133159A1 (en) * | 2009-05-22 | 2010-11-25 | 华为技术有限公司 | Method for amplifying burst optical signal, burst optical amplifier and system, and communication system |
| CN104038287A (en) * | 2014-04-09 | 2014-09-10 | 国家电网公司 | Ultra-long-spaced OPGW (Optical Fiber Composite Overhead Ground Wire) optical fiber communication system capable of obtaining energy on site and implementation method thereof |
| CN106785836A (en) * | 2016-12-14 | 2017-05-31 | 电子科技大学 | A kind of fiber amplifier for suppressing optical fiber laser output intensity noise |
| CN109728854A (en) * | 2018-11-20 | 2019-05-07 | 武汉光迅科技股份有限公司 | To remote gain unit and remote optical pumping amplifier before a kind of |
| CN112563872A (en) * | 2020-12-10 | 2021-03-26 | 江苏师范大学 | Dual-wavelength pumping thulium-doped laser based on GSA and ESA |
| CN114884574A (en) * | 2022-04-22 | 2022-08-09 | 华中科技大学 | L-band expansion hybrid optical fiber amplifier |
| EP4001749A4 (en) * | 2019-07-19 | 2022-11-09 | Institute for Laser Technology | Light-emitting device and optical fiber |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5875203A (en) * | 1996-12-13 | 1999-02-23 | The Board Of Trustees Of The Leland Stanford Junior University | Stable fiber ASE sources incorporating spectral filtering |
| US6233092B1 (en) * | 1998-10-16 | 2001-05-15 | Corning Incorporated | Management and utilization of ASE in optical amplifier |
| KR100407326B1 (en) * | 2002-02-27 | 2003-11-28 | 삼성전자주식회사 | Wide band erbium doped fiber amplifier for minimizing band crosstalk |
| JP2005520326A (en) * | 2002-03-08 | 2005-07-07 | ライトウェーブ エレクトロニクス | Amplifier and light source using S-band erbium-doped fiber and L-band thulium-doped fiber to suppress dispersion of amplified spontaneous emission (ASE) |
| CN2549496Y (en) * | 2002-06-06 | 2003-05-07 | 华为技术有限公司 | Erbium dosed optical fiber amplifier |
-
2003
- 2003-12-30 CN CNB2003101116844A patent/CN1317600C/en not_active Expired - Lifetime
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010133159A1 (en) * | 2009-05-22 | 2010-11-25 | 华为技术有限公司 | Method for amplifying burst optical signal, burst optical amplifier and system, and communication system |
| CN104038287A (en) * | 2014-04-09 | 2014-09-10 | 国家电网公司 | Ultra-long-spaced OPGW (Optical Fiber Composite Overhead Ground Wire) optical fiber communication system capable of obtaining energy on site and implementation method thereof |
| CN106785836A (en) * | 2016-12-14 | 2017-05-31 | 电子科技大学 | A kind of fiber amplifier for suppressing optical fiber laser output intensity noise |
| CN109728854A (en) * | 2018-11-20 | 2019-05-07 | 武汉光迅科技股份有限公司 | To remote gain unit and remote optical pumping amplifier before a kind of |
| CN109728854B (en) * | 2018-11-20 | 2020-06-02 | 武汉光迅科技股份有限公司 | Forward remote gain unit and remote pump amplifier |
| EP4001749A4 (en) * | 2019-07-19 | 2022-11-09 | Institute for Laser Technology | Light-emitting device and optical fiber |
| CN112563872A (en) * | 2020-12-10 | 2021-03-26 | 江苏师范大学 | Dual-wavelength pumping thulium-doped laser based on GSA and ESA |
| CN114884574A (en) * | 2022-04-22 | 2022-08-09 | 华中科技大学 | L-band expansion hybrid optical fiber amplifier |
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| Publication number | Publication date |
|---|---|
| CN1317600C (en) | 2007-05-23 |
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Granted publication date: 20070523 |