CN102736354A - Multi-wavelength optical differentiator based on dual-core optical fiber - Google Patents
Multi-wavelength optical differentiator based on dual-core optical fiber Download PDFInfo
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- CN102736354A CN102736354A CN201210214662XA CN201210214662A CN102736354A CN 102736354 A CN102736354 A CN 102736354A CN 201210214662X A CN201210214662X A CN 201210214662XA CN 201210214662 A CN201210214662 A CN 201210214662A CN 102736354 A CN102736354 A CN 102736354A
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Abstract
The invention discloses a multi-wavelength optical differentiator based on a dual-core optical fiber and relates to optical fiber communication, optical fiber sensing and optical signal processing technologies. The multi-wavelength optical differentiator comprises a tunable laser array (1), an electric signal generator (2), an electro-optical modulator (3), a dual-core optical fiber differentiator (4), a first detection system (51) and a second detection system (52), wherein the dual-core optical fiber differentiator (4) is the dual-core optical fiber; and two fiber cores are identical in refractive index and radius, so the wave guide modes of the two fiber cores are completely coupled. An interval between the two fiber cores is between a dozen of microns and dozens of microns, the length of the dual-core optical fiber is dozens of centimeters, and the position of a central wavelength and the quantity of wavelengths can be adjusted by changing the length of the dual-core optical fiber. The multi-wavelength optical differentiator is simple in structure, low in cost and high in cost performance, and the position of the central wavelength and the quantity of the wavelengths are adjustable.
Description
Technical field
The present invention is a kind of multi-wavelength light differentiator, relates to optical fiber communication, Fibre Optical Sensor, optical signalling treatment technology, just is based on the multi-wavelength light differentiator of twin-core fiber specifically.
Background technology
Along with communication and rapid development of computer technology; Signal of communication speed is increasingly high; In electric territory signal is handled the more and more difficult that becomes, a kind of effective solution is in the light territory signal to be handled, based on this purpose; The signal processor that just needs some light territories of development and Design, light differentiator are exactly one of them very important optical signal processor part.The optical differential device is a kind of full optical device that can be in the light territory light field of light signal be carried out the time-derivative computing; The light differentiator has its some intrinsic advantages, as make simple, with low cost, insert loss low, with polarization irrelevant, have very high compatibility with existing optical communication system, can handle the two-forty signal of Gbit even Tbit.Exactly because these advantages that the light differentiator is intrinsic, so the light differentiator has application widely in fields such as the processing of the light territory of shaping pulse, microwave signal, image processings.
Up to the present, people have proposed multiple smooth differentiator implementation.2005, people such as Kulishov published an article at " Optics Letters " " Long-period fiber gratings as ultrafast optical differentiators ", proposed to use LPFG to realize the scheme of light differentiator.This differentiator can processing bandwidth greater than the light signal of 100GHz, when signal bandwidth during less than 1GHz, this differentiator has very low energy efficiency; Owing to the intrinsic susceptibility to environment of LPFG, the variation meeting of surrounding environment causes very big influence to the serviceability of this smooth differentiator in addition.2007; Berger; N. people such as K. publish an article at " Optics Express " " Temporal differentiation of optical signals using a phase-shifted fiber Bragg grating "; Propose to use the phase shift bragg grating to realize the scheme of light differentiator, this scheme is used two uniform bragg gratings, and strict π phase shift is arranged between these two gratings.Utilize the transport property of its reflectance spectrum to have similar characteristics, the time first order differential is provided the light field of light signal with the transport property of single order light differentiator.But this scheme requires to have strict π phase shift between two gratings, therefore realizes difficulty.Chinese invention patent " based on the light differentiator of silicon based annular resonant cavity " (application number: 200810039557.0) utilize silicon based annular resonant cavity to realize the light differentiator; When silicon based annular resonant cavity was operated in the critical coupling state, its spectral characteristic and first order differential utensil had well approximate.Made difficulty but should invent, and needed accurately to control the slit between ring resonator and the straight wave guide, and can only provide differential to handle, can not handle the optical signalling of a plurality of wavelength simultaneously the light signal of a wavelength.
Summary of the invention
The present invention has proposed a kind of multi-wavelength light differentiator based on twin-core fiber in order to overcome the deficiency of prior art.This invention has utilized the Mode Coupling between the twin-core fiber fibre core, and when being operated in complete couple state, the transmission spectrum of two fibre cores and first order differential utensil have well approximate; Two fibre cores all can be realized the light derivation operation of multi-wavelength; The transmission spectrum of two fibre cores has different centre wavelength, and through changing the length of twin-core fiber, can regulate the position and the number of wavelengths of centre wavelength; Twin-core fiber length is long more, and supported number of wavelengths is many more.
Technical scheme of the present invention:
Based on the multi-wavelength light differentiator of twin-core fiber, this invention comprises tunable laser array, electric signal generator, electrooptic modulator, twin-core fiber differentiator, first detection system, second detection system.Wherein the tunable laser array connects the light input end of electrooptic modulator; The electrical input of electric signal generator output termination electrooptic modulator; The light output end of electrooptic modulator connects the input end of first fibre core of twin-core fiber differentiator; Output termination first detection system of first fibre core of twin-core fiber differentiator, output termination second detection system of second fibre core of twin-core fiber differentiator.
Described twin-core fiber differentiator is one section twin-core fiber, and refractive index, the fiber core radius of two fibre cores are identical, and the guided wave mode between such two fibre cores can be realized being coupled fully.The spacing of two fibre cores is tens to tens microns, and the length of twin-core fiber is tens centimetres.
Beneficial effect of the present invention is specific as follows:
A kind of multi-wavelength light differentiator based on twin-core fiber that the present invention proposes can be realized simultaneously the light signal of multi-way optical-wavelength is carried out the operation of time domain first order differential, and just can adjust centre wavelength position and number of wavelengths through the length that changes twin-core fiber.The present invention only uses one section twin-core fiber just can realize above-mentioned functions, has simple in structure, low price, cost performance is high, good with existing fiber communication system compatibility, welding convenient, the advantage of number of wavelengths and centre wavelength adjustable positions.
Description of drawings
Fig. 1 is based on the multi-wavelength differentiator synoptic diagram of twin-core fiber.
Fig. 2 Gauss pulse time domain waveform synoptic diagram.
Fig. 32 wavelength twin-core fiber differentiators first fibre core transmission spectrum amplitude versus frequency characte synoptic diagram.
Fig. 42 wavelength twin-core fiber differentiators first fibre core transmission spectrum phase-frequency characteristic synoptic diagram.
Fig. 52 wavelength twin-core fiber differentiators second fibre core transmission spectrum amplitude versus frequency characte synoptic diagram.
Fig. 62 wavelength twin-core fiber differentiators second fibre core transmission spectrum phase-frequency characteristic synoptic diagram.
Fig. 7 Gauss first order differential time domain plethysmographic signal synoptic diagram.
Fig. 84 wavelength twin-core fiber differentiators first fibre core transmission spectrum amplitude versus frequency characte synoptic diagram.
Fig. 94 wavelength twin-core fiber differentiators first fibre core transmission spectrum phase-frequency characteristic synoptic diagram.
Figure 10 4 wavelength twin-core fiber differentiators second fibre core transmission spectrum amplitude versus frequency characte synoptic diagram.
Figure 11 4 wavelength twin-core fiber differentiators second fibre core transmission spectrum phase-frequency characteristic synoptic diagram.
Figure 12 6 wavelength twin-core fiber differentiators first fibre core transmission spectrum amplitude versus frequency characte synoptic diagram.
Figure 13 6 wavelength twin-core fiber differentiators first fibre core transmission spectrum phase-frequency characteristic synoptic diagram.
Figure 14 6 wavelength twin-core fiber differentiators second fibre core transmission spectrum amplitude versus frequency characte synoptic diagram.
Figure 15 6 wavelength twin-core fiber differentiators second fibre core transmission spectrum phase-frequency characteristic synoptic diagram.
Figure 16 8 wavelength twin-core fiber differentiators first fibre core transmission spectrum amplitude versus frequency characte synoptic diagram.
Figure 17 8 wavelength twin-core fiber differentiators first fibre core transmission spectrum phase-frequency characteristic synoptic diagram.
Figure 18 8 wavelength twin-core fiber differentiators second fibre core transmission spectrum amplitude versus frequency characte synoptic diagram.
Figure 19 8 wavelength twin-core fiber differentiators second fibre core transmission spectrum phase-frequency characteristic synoptic diagram.
Embodiment
Below in conjunction with accompanying drawing 1 to 19, to further describing based on twin-core fiber multi-wavelength light differentiator.
Embodiment one
Based on the multi-wavelength light differentiator of twin-core fiber, this differentiator comprises tunable laser array 1, electric signal generator 2, electrooptic modulator 3, twin-core fiber differentiator 4, first detection system 51, second detection system 52.
Concrete connected mode is:
The half-wave overall with that electric signal generator 2 output Gauss pulses are set is 10 psecs.
The fibre core spacing that twin-core fiber differentiator 4 is set is from being 10 microns, and length is 10 centimetres.The amplitude versus frequency characte of the first fibre core transmission spectrum is as shown in Figure 3, and the phase-frequency characteristic of the first fibre core transmission spectrum is as shown in Figure 4, and the amplitude versus frequency characte of the second fibre core transmission spectrum is as shown in Figure 5, and the phase-frequency characteristic of the second fibre core transmission spectrum is as shown in Figure 6.Can find out that from the amplitude versus frequency characte of Fig. 3 and Fig. 5 the off resonance amount of the relative centre frequency with frequency of core light field amplitude (carrier frequency) is directly proportional; Can find out from the phase-frequency characteristic of Fig. 4 and Fig. 6, locate that strict π phase shift is arranged, meet the theoretical transport property of differentiator in the centre frequency (carrier frequency) of transmission spectrum.The centre frequency of first fibre core transmission spectrum is 1470nm, and the centre frequency of second fibre core transmission spectrum is 1592nm, therefore can realize the light differentiator of 2 wavelength.
The output light wavelength that tunable laser array 1 is set is 1470nm and 1592nm, aligns with the centre wavelength of two fiber optic, light differentiators.
Gauss light pulse from electrooptic modulator 3 outputs; Be input to the first fibre core input end 41 of twin-core light differentiator 4; Differential through twin-core fiber differentiator 4 is handled; Be input to first detection system 51 from the light signal of the first fibre core output terminal, 43 outputs, can obtain Gauss's first order differential signal, its time domain waveform is as shown in Figure 7; Be input to first detection system 52 from the light signal of the second fibre core output terminal, 44 outputs, can obtain Gauss's first order differential signal, its time domain waveform is as shown in Figure 7.
Embodiment two
Based on the multi-wavelength light differentiator of twin-core fiber, this differentiator comprises tunable laser array 1, electric signal generator 2, electrooptic modulator 3, twin-core fiber differentiator 4, first detection system 51, second detection system 52.
Concrete connected mode is:
The half-wave overall with that electric signal generator 2 output Gauss pulses are set is 10 psecs.
The fibre core spacing that twin-core fiber differentiator 4 is set is from being 10 microns, and length is 20 centimetres.The amplitude versus frequency characte of the first fibre core transmission spectrum is as shown in Figure 8, and the phase-frequency characteristic of the first fibre core transmission spectrum is as shown in Figure 9, and the amplitude versus frequency characte of the second fibre core transmission spectrum is shown in figure 10, and the phase-frequency characteristic of the second fibre core transmission spectrum is shown in figure 11.Can find out that from the amplitude versus frequency characte of Fig. 8 and Figure 10 the off resonance amount of the relative centre frequency with frequency of core light field amplitude (carrier frequency) is directly proportional; Can find out from the phase-frequency characteristic of Fig. 9 and Figure 11, locate that strict π phase shift is arranged, meet the theoretical transport property of differentiator in the centre frequency (carrier frequency) of transmission spectrum.The centre frequency of first fibre core transmission spectrum is 1413nm and 1531nm, and the centre frequency of second fibre core transmission spectrum is 1470nm and 1592nm, therefore can realize the light differentiator of 4 wavelength.
The output light wavelength that tunable laser array 1 is set is 1413nm, 1470nm, 1531nm, 1592nm, aligns with the centre wavelength of two fiber optic, light differentiators.
Gauss light pulse from electrooptic modulator 3 outputs; Be input to the first fibre core input end 41 of twin-core light differentiator 4; Differential through twin-core fiber differentiator 4 is handled; Be input to first detection system 51 from the light signal of the first fibre core output terminal, 43 outputs, can obtain Gauss's first order differential signal, its time domain waveform is as shown in Figure 7; Be input to first detection system 52 from the light signal of the second fibre core output terminal, 44 outputs, can obtain Gauss's first order differential signal, its time domain waveform is as shown in Figure 7.
Embodiment three
Based on the multi-wavelength light differentiator of twin-core fiber, this differentiator comprises tunable laser array 1, electric signal generator 2, electrooptic modulator 3, twin-core fiber differentiator 4, first detection system 51, second detection system 52.
Concrete connected mode is:
The half-wave overall with that electric signal generator 2 output Gauss pulses are set is 10 psecs.
The fibre core spacing that twin-core fiber differentiator 4 is set is from being 10 microns, and length is 25 centimetres.The amplitude versus frequency characte of the first fibre core transmission spectrum is shown in figure 12, and the phase-frequency characteristic of the first fibre core transmission spectrum is shown in figure 13, and the amplitude versus frequency characte of the second fibre core transmission spectrum is shown in figure 14, and the phase-frequency characteristic of the second fibre core transmission spectrum is shown in figure 15.Can find out that from the amplitude versus frequency characte of Figure 12 and Figure 14 the off resonance amount of the relative centre frequency with frequency of core light field amplitude (carrier frequency) is directly proportional; Can find out from the phase-frequency characteristic of Figure 13 and Figure 15, locate that strict π phase shift is arranged, meet the theoretical transport property of differentiator in the centre frequency (carrier frequency) of transmission spectrum.The centre frequency of first fibre core transmission spectrum is 1447nm, 1543nm, 1650nm, and the centre frequency of second fibre core transmission spectrum is 1402nm, 1495nm, 1592nm.Therefore can realize the light differentiator of 6 wavelength.
The output light wavelength that tunable laser array 1 is set is 1402nm, 1447nm, 1495nm, 1543nm, 1592nm, 1650nm, aligns with the centre wavelength of two fiber optic, light differentiators.
Gauss light pulse from electrooptic modulator 3 outputs; Be input to the first fibre core input end 41 of twin-core light differentiator 4; Differential through twin-core fiber differentiator 4 is handled; Be input to first detection system 51 from the light signal of the first fibre core output terminal, 43 outputs, can obtain Gauss's first order differential signal, its time domain waveform is as shown in Figure 7; Be input to first detection system 52 from the light signal of the second fibre core output terminal, 44 outputs, can obtain Gauss's first order differential signal, its time domain waveform is as shown in Figure 7.
Embodiment four
Based on the multi-wavelength light differentiator of twin-core fiber, this differentiator comprises tunable laser array 1, electric signal generator 2, electrooptic modulator 3, twin-core fiber differentiator 4, first detection system 51, second detection system 52.
Concrete connected mode is:
The half-wave overall with that electric signal generator 2 output Gauss pulses are set is 10 psecs.
The fibre core spacing that twin-core fiber differentiator 4 is set is from being 10 microns, and length is 30 centimetres.The amplitude versus frequency characte of the first fibre core transmission spectrum is shown in figure 16, and the phase-frequency characteristic of the first fibre core transmission spectrum is shown in figure 17, and the amplitude versus frequency characte of the second fibre core transmission spectrum is shown in figure 18, and the amplitude-frequency and the phase-frequency characteristic of the second fibre core transmission spectrum are shown in figure 19.Can find out that from the amplitude versus frequency characte of Figure 16 and Figure 18 the off resonance amount of the relative centre frequency with frequency of core light field amplitude (carrier frequency) is directly proportional; Can find out from the phase-frequency characteristic of Figure 17 and Figure 19, locate that strict π phase shift is arranged, meet the theoretical transport property of differentiator in the centre frequency (carrier frequency) of transmission spectrum.The centre frequency of first fibre core transmission spectrum is 1395nm, 1471nm, 1551nm, 1640nm, and the centre frequency of second fibre core transmission spectrum is 1355nm, 1431nm, 1511nm, 1592nm.Therefore can realize the light differentiator of 8 wavelength.
The output light wavelength that tunable laser array 1 is set is 1355nm, 1395nm, 1431nm, 1471nm, 1511nm, 1551nm, 1592nm, 1640nm, aligns with the centre wavelength of two fiber optic, light differentiators.
Gauss light pulse from electrooptic modulator 3 outputs; Be input to the first fibre core input end 41 of twin-core light differentiator 4; Differential through twin-core fiber differentiator 4 is handled; Be input to first detection system 51 from the light signal of the first fibre core output terminal, 43 outputs, can obtain Gauss's first order differential signal, its time domain waveform is as shown in Figure 7; Be input to first detection system 52 from the light signal of the second fibre core output terminal, 44 outputs, can obtain Gauss's first order differential signal, its time domain waveform is as shown in Figure 7.
Claims (3)
1. based on the multi-wavelength light differentiator of twin-core fiber, it is characterized in that: comprise tunable laser array (1), electric signal generator (2), electrooptic modulator (3), twin-core fiber differentiator (4), first detection system (51), second detection system (52);
Connected mode between the described device is:
Tunable laser array (1) connects the light input end of electrooptic modulator (3); The electrical input of electric signal generator (2) output termination electrooptic modulator (3); The light output end of electrooptic modulator (3) connects the input end (41) of first fibre core of twin-core fiber differentiator (4); The output terminal (43) of first fibre core of twin-core fiber differentiator (4) connects first detection system (51), and the output terminal (44) of second fibre core of twin-core fiber differentiator (4) connects second detection system (52).
2. the multi-wavelength light differentiator based on twin-core fiber according to claim 1 is characterized in that the refractive index and the fiber core radius of two fibre cores of described twin-core fiber differentiator (4) are in full accord, and the distance between the fibre core is tens to tens microns.
3. the multi-wavelength light differentiator based on twin-core fiber according to claim 1 is characterized in that, through changing the length of twin-core fiber differentiator (4), can regulate position and the quantity of centre wavelength of the centre wavelength of twin-core fiber differentiator (4).
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103760734A (en) * | 2013-08-12 | 2014-04-30 | 西南交通大学 | Reconfigurable all-optical differentiator based on differential group delay |
| CN105589223A (en) * | 2016-03-10 | 2016-05-18 | 哈尔滨工程大学 | Multi-core optical fiber beam splitter with phase modulation function |
| CN105785603A (en) * | 2016-02-29 | 2016-07-20 | 北京交通大学 | Multi-wavelength light differentiator based on optical fiber Sagnac ring |
Citations (1)
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| CN101369852A (en) * | 2003-03-10 | 2009-02-18 | 松下电器产业株式会社 | Pulse train optical transmission system and transmitter and receiver apparatuses used therein |
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Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101369852A (en) * | 2003-03-10 | 2009-02-18 | 松下电器产业株式会社 | Pulse train optical transmission system and transmitter and receiver apparatuses used therein |
Non-Patent Citations (1)
| Title |
|---|
| TAE-JUNG AHN AND JOSE AZANA: "Wavelength-selective directional couplers as ultrafast optical differentiators", 《OPTICS EXPRESS》, vol. 19, no. 8, 11 April 2011 (2011-04-11) * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103760734A (en) * | 2013-08-12 | 2014-04-30 | 西南交通大学 | Reconfigurable all-optical differentiator based on differential group delay |
| CN103760734B (en) * | 2013-08-12 | 2016-10-05 | 西南交通大学 | The full light differentiator of restructural based on Differential Group Delay |
| CN105785603A (en) * | 2016-02-29 | 2016-07-20 | 北京交通大学 | Multi-wavelength light differentiator based on optical fiber Sagnac ring |
| CN105785603B (en) * | 2016-02-29 | 2019-02-15 | 北京交通大学 | Multi-wavelength light differentiator based on optical fiber Sagnac ring |
| CN105589223A (en) * | 2016-03-10 | 2016-05-18 | 哈尔滨工程大学 | Multi-core optical fiber beam splitter with phase modulation function |
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Application publication date: 20121017 |