CN116053901A

CN116053901A - Amplifier and system

Info

Publication number: CN116053901A
Application number: CN202111261103.XA
Authority: CN
Inventors: 谭斯斯; 吴波
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-10-28
Filing date: 2021-10-28
Publication date: 2023-05-02
Also published as: WO2023071306A1

Abstract

The embodiment of the application provides an optical fiber amplifier, which comprises: the device comprises at least one wave combiner, at least one amplifying module and at least one auxiliary light source, wherein the amplifying module receives input signal light and amplifies the input signal light by using pump light to obtain output signal light, and the input signal light is L-band signal light; the light source of the auxiliary light is used for generating auxiliary light, the wavelength of the auxiliary light is in a C wave band, the optical power of the auxiliary light is smaller than the optical power of the input signal light, and the optical power of the auxiliary light is smaller than the optical power of the pumping light; the combiner is used for coupling the auxiliary light into the amplifying module. Based on the scheme of the application, the accumulation of ASE of the C wave band is restrained by introducing the auxiliary light of the C wave band into the optical fiber amplifier, so that the consumption of the ASE of the C wave band to pumping power is reduced, and the pumping efficiency of amplifying the signal light of the L wave band is improved.

Description

Amplifier and system

Technical Field

Embodiments of the present application relate to the field of optical communications, and more particularly, to an amplifier and system.

Background

With the development of communication technologies, new services and applications such as fifth generation mobile communication technologies (5th generation mobile communication technology,5G), augmented reality (augmented reality, AR), virtual Reality (VR), cloud computing, high definition video, and internet of things are rapidly emerging, and demands for network traffic are rapidly increasing. Currently, two schemes for improving the transmission capacity of a network are used to increase the number of optical fiber deployments and improve the transmission capacity of a single fiber. The spectrum bandwidth expansion based on the wavelength division technology has the advantages of convenient and flexible implementation, high economic benefit and the like, and is a preferred expansion scheme at present.

As an important component of an optical communication system, an optical amplifier is one of the most difficult optical devices in spectrum bandwidth expansion technology. The conventional wavelength band (conventional band, C) ranges from 1530nm to 1565nm and is located in a section with a high emission coefficient in the emission spectrum of an erbium-doped fiber (EDF), so that the high-particle-number inversion is easy to realize, thereby obtaining a high-gain low-noise erbium-doped fiber amplifier (EDFA) meeting the communication requirement. However, as the C-band spectrum resources are exhausted, it is a current research hotspot to implement optical communication using long-wavelength (L) bands (typically 1565nm to 1625 nm).

Compared with the C band, the L band is positioned at the edge of the EDF emission spectrum, the emission coefficient is low, and the conversion efficiency of optical amplification is low, so that the requirement of the optical amplification of the L band on pump power is high by using the EDF, the overall power consumption of an erbium-doped fiber amplifier (erbium-doped fiber Amplifier, EDFA) is increased, and meanwhile, the cost of a wavelength division multiplexing (wavelength division multiplexing, WDM) system is high.

Therefore, how to improve the pumping efficiency of the L-band optical amplifier is a problem to be solved.

Disclosure of Invention

The application provides an optical fiber amplifier for the optical fiber communication field can promote L wave band light and put pumping efficiency to and can realize the dynamic gain adjustment of L wave band light amplification.

In a first aspect, an embodiment of the present invention provides an optical fiber amplifier, including: the device comprises at least one wave combiner, at least one amplifying module and at least one auxiliary light source, wherein the amplifying module receives input signal light and amplifies the input signal light by using pump light to obtain output signal light, and the input signal light is L-band signal light; the light source of the auxiliary light is used for generating auxiliary light, the wavelength of the auxiliary light is in a C wave band, the optical power of the auxiliary light is smaller than the optical power of the input signal light, and the optical power of the auxiliary light is smaller than the optical power of the pumping light; the combiner is used for coupling the auxiliary light into the amplifying module.

Based on the scheme, the auxiliary light of the C wave band is introduced into the optical fiber amplifier to inhibit the accumulation of ASE of the C wave band, so that the consumption of the ASE of the C wave band on pumping power is reduced, and the pumping efficiency of amplifying the signal light of the L wave band is improved.

With reference to the first aspect, in certain implementations of the first aspect, the amplifier further includes: the optical splitter is used for separating light to be measured in the output signal light, and the wavelength of the light to be measured is a C wave band; the light detector is used for measuring the optical power of the light to be measured, the light source of the auxiliary light and adjusting the wavelength of the auxiliary light and/or the optical power of the auxiliary light based on the optical power of the light to be measured.

Based on the scheme, the C/L wave splitter is introduced into the output end of the L wave band optical amplifier to filter out C wave band light for power detection, and the power and the wavelength of the C wave band seed light are adjusted through feedback so as to realize the dynamic gain adjustment of the L wave band optical amplification, thereby reducing the loss of L wave band signal light and being beneficial to the performance improvement of the L wave band optical amplifier.

With reference to the first aspect, in certain implementations of the first aspect, the amplifier further includes: and the filter is used for filtering the C-band spontaneous emission noise in the light to be measured.

With reference to the first aspect, in certain implementations of the first aspect, the amplifying module includes: the device comprises a wavelength division multiplexer, a light source of pump light and a gain optical fiber, wherein the wavelength division multiplexer is used for coupling the pump light into the gain optical fiber; the light source of the pump light is used for generating the pump light; the gain fiber amplifies the input signal light by using the pump light, and the gain fiber is an erbium-doped fiber.

With reference to the first aspect, in certain implementations of the first aspect, a wavelength of the pump light is less than a wavelength of the C-band signal light, and a wavelength of the first pump light is 980nm or 1480nm.

Based on the scheme, the amplifier provided by the application adopts common pump light when amplifying the L-band signal light, and compared with the pump of the C-band, the cost of the device can be reduced.

With reference to the first aspect, in certain implementation manners of the first aspect, the combiner is disposed at an input end of the amplifying module, and the combiner is further configured to couple the input light with the auxiliary light to generate first coupled signal light, where the combiner is configured to couple the auxiliary light into the amplifying module, and includes: the combiner is used for coupling the first coupling signal light into the amplifying module.

With reference to the first aspect, in certain implementations of the first aspect, the combiner is disposed at an output of the amplifying module.

In a second aspect, an embodiment of the present invention provides an optical fiber communication system, including an optical amplification station, where the optical amplification station includes the foregoing optical fiber amplifier, and is configured to amplify the input signal light.

Drawings

Fig. 1 shows a schematic diagram of a fiber optic communication network to which embodiments of the present application may be applied.

Fig. 2 shows a basic structure of a fiber amplifier.

Fig. 3 shows a schematic diagram of an apparatus for an L-band optical fiber amplifier based on C-band pump light.

Fig. 4 shows a schematic diagram of an optical fiber amplifier 400 according to an embodiment of the present application.

Fig. 5 shows a schematic diagram of an optical fiber amplifier 500 according to an embodiment of the present application.

Fig. 6 shows a schematic diagram of an optical fiber amplifier 600 provided in an embodiment of the present application.

Fig. 7 shows a schematic diagram of an optical fiber amplifier 700 according to an embodiment of the present application.

Fig. 8 shows a schematic diagram of an optical fiber amplifier 800 according to an embodiment of the present application.

Fig. 9 shows a schematic diagram of an optical fiber amplifier 900 according to an embodiment of the present application.

Fig. 10 shows a schematic diagram of an optical fiber amplifier 1000 according to an embodiment of the present application.

Fig. 11 shows a schematic diagram of an optical fiber amplifier 1100 according to an embodiment of the present application.

Fig. 12 shows a schematic diagram of an optical fiber amplifier 1200 provided in an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings.

The technical scheme of the embodiment of the application can be applied to an optical fiber communication network, for example, the technical scheme of the embodiment of the application can be applied to an optical fiber amplifier in the optical fiber communication network, and the optical fiber amplifier is mainly positioned at an optical amplifying station and an optical amplifying network element in the optical fiber communication network. The technical scheme of the embodiment of the application can be used for realizing the optical fiber amplifier for amplifying the L-band signal.

Fig. 1 is a schematic diagram of an application scenario suitable for the embodiments of the present application. In a fiber optic communications network, an optical transmitter, an optical receiver, and one or more fiber optic amplifiers may be included. As shown in fig. 1, the optical fiber amplifier is mainly located in the middle of an optical fiber line (or a line optical fiber) in an optical fiber communication network, so as to amplify an optical signal and prolong the transmission distance of the optical signal.

It should be understood that fig. 1 is merely an exemplary illustration, and the present application is not limited thereto. For example, more optical devices may be included in a fiber optic communication network, or embodiments of the present application may be applied in any scenario involving a fiber optic amplifier.

To facilitate an understanding of the embodiments of the present application, a fiber amplifier is first briefly described in conjunction with fig. 2. As shown in fig. 2, the fiber amplifier may include, for example, but is not limited to: pump lasers, wavelength division multiplexers (wavelength division multiplexer, WDM), isolators, gain fibers. Wherein the pump laser generates pump light, and the WDM can combine the input optical signal (or input signal light) with the pump light and deliver the combined pump light to the gain fiber. The gain fiber may be an optical fiber in which a gain medium is doped. In the gain fiber, the pump light excites the gain medium ions in the gain fiber to a high energy level, and when the input optical signal is input, the gain medium ions in the gain fiber are caused to transition from the high energy level to a low energy level, stimulated radiation occurs, so that the input optical signal is amplified, and the output optical signal is obtained.

In the optical fiber amplifier, the connection between the gain optical fiber and the WDM and the connection between the gain optical fiber and the isolator can be generally realized by adopting an optical fiber fusion connection mode, so that the loss can be reduced and the noise coefficient can be reduced. For example, in fig. 2, the pigtails of the WDM and the gain fibers are fused together, and the pigtails of the isolators and the gain fibers are fused together. In the optical fiber communication network, the gain fiber in the common optical fiber amplifier is the quartz glass matrix erbium-doped fiber, so that the tail fiber of the optical devices such as WDM and isolator can generally adopt the quartz glass matrix fiber, i.e. the matrixes of the quartz glass matrix fiber and the quartz glass matrix fiber are the same.

Currently, in an optical fiber amplifier for amplifying an L-band, in order to improve the pumping efficiency of the L-band optical amplifier, long wavelength pumping with higher pumping efficiency, for example, C-band light of 1530nm is selected as pumping light for amplifying signal light of the L-band, compared to conventional 980nm or 1480nm pumping. For example, in the multi-stage (three-stage in fig. 3) L-band bang optical fiber amplifier shown in fig. 3, a conventional 980nm pump uniform optical Noise Figure (NF) is adopted in the first stage of the three-stage L-band optical amplifier, and 1530nm pump with higher pumping efficiency is adopted in the latter two stages, so as to realize higher-efficiency L-band optical amplification.

However, the scheme is also essentially incapable of suppressing accumulation of spontaneous emission light amplification (amplified spontaneous emission, ASE) generated during the light amplification process due to the difficult availability and high cost of the high-power C-band pump signal, and thus, the application scenario is limited.

In view of this, the present application proposes an amplifier for L-band optical amplification and a method of amplifying an optical signal, in which the accumulation of C-band ASE is suppressed by introducing C-band signal light, and the consumption of pump light power by the C-band ASE is reduced, thereby achieving an enhancement in the pump efficiency of L-band signal light amplification. In addition, the amplifier for L-band optical amplification and the method for amplifying the optical signal can realize dynamic gain adjustment of L-band optical amplification by adjusting the power and/or the wavelength of the introduced signal light of the C-band through feedback.

Various embodiments provided herein will be described in detail below with reference to the accompanying drawings.

The following description is made in order to facilitate understanding of the embodiments of the present application.

First, second, third, fourth, and various numerical numbers are merely for convenience of description and are not intended to limit the scope of the embodiments of the present application in the embodiments of the present application. For example, distinguishing between different states of the optical signal after different steps, etc.

In a second, hereinafter illustrated embodiment of the present application, the optical elements are connected by optical fibers, and specifically, the input or output pigtails of the elements and the transmission fiber together form a length of optical fiber, which is used for transmitting signal light between the elements.

Third, in the embodiments of the present application shown below, "and/or" may be used to describe that there are three relationships of associated objects, e.g., a and/or B, which may represent: a exists alone, A and B exist together, and B exists alone. Wherein A, B may be singular or plural.

Fig. 4 shows a schematic diagram of an optical fiber amplifier 400 according to an embodiment of the present application, where the optical fiber amplifier 400 may be used to amplify L-band signal light.

In one implementation, as shown in fig. 4, the amplifier 400 may include:

a single-stage amplification module 410, a light source 420 for auxiliary light, and a combiner 430.

The single-stage amplifying module 410 is configured to receive the input signal light, and amplify the input signal light with the pump light to obtain output signal light.

A light source 420 for generating auxiliary light.

And a combiner 430 for coupling the auxiliary light into the amplifying module.

The wavelength of the input signal light is L-band signal light, the wavelength of the auxiliary light is C-band light, and the optical power of the auxiliary light is smaller than the optical power of the input signal light and the optical power of the pump light.

The single stage amplification module 410 may include a first WDM 411, an EDF412, and a source 413 of pump light, which source 413 may be 980nm or 1480nm laser pumping.

Specifically, the light source 420 of the auxiliary light generates C-band auxiliary light, the C-band auxiliary light is input to the combiner 430 through an optical fiber, the combiner 430 generates first coupling signal light by the received L-band input signal light and the C-band auxiliary light, the first coupling signal light is input to the input end of the first WDM 411 through an output optical fiber, the first WDM 411 couples the first coupling signal light with the pump light generated by the light source 413 of the pump light to form second coupling signal light, the second coupling signal light is input to the input end of the EDF412 through an output optical fiber, and the EDF412 amplifies the L-band input signal light in the first coupling signal light by the pump light in the second coupling signal light to obtain amplified L-band output signal light.

The light source 420 of the auxiliary light may be a semiconductor light emitting diode, a laser diode, or a fiber laser.

According to the principle of the optical fiber amplifier, the erbium ion in the EDF412 absorbs photons of the pump light to a high energy level, and the photons with the same wavelength as the L-band input signal light are released after stimulated radiation back to the base station, so as to amplify the signal light.

The EDF412 is pumped with 980nm or 1480nm laser light, accompanied by ASE due to the EDF. That is, with the enhancement of the pump light, the particle numbers will show inverse distribution, and when the spontaneous radiation light generated by the high-level atoms propagates in the optical fiber, the spontaneous radiation light is continuously stimulated and amplified to form the ASE of the C-band and the ASE of the L-band. In contrast, after the erbium ions absorb 980nm or 1480nm pump laser, C-band ASE is first generated at the front end of the EDF412, and the generated C-band ASE is then absorbed by the back end EDF412, and is used as a secondary pump source to shift the ASE spectrum to the L-band to form an L-band ASE spectrum. Since the tail of the erbium ion gain band is used for the ASE of the L-band, the emission and absorption coefficients of the tail are much lower than those of the C-band, and only longer EDF can generate more obvious ASE of the L-band. Therefore, ASE affecting the pump conversion efficiency is mainly that of the C-band.

In order to eliminate the consumption of the optical power of the pump light by the C-band ASE, the present application inputs the C-band auxiliary light at the same time in the EDF412, and the optical power of the C-band auxiliary light is relatively high, so that the C-band auxiliary light consumes the optical power of the pump light first, and since the C-band auxiliary light is a narrowband light source compared with the broadband C-band ASE light source, when the same gain is obtained, the optical power of the pump light consumed by the C-band auxiliary light is smaller than the optical power of the pump light consumed by the C-band ASE, so that the C-band ASE is suppressed.

Based on the scheme, the amplifier can inhibit the ASE of the C wave band by introducing the auxiliary light of the C wave band, so that the pumping efficiency of the L wave band optical amplifier is improved, and the gain performance of the L wave band optical amplifier is improved.

In another implementation, as shown in fig. 4, the amplifier 400 may further include:

a first isolator 440 and/or a second isolator 450.

Specifically, the amplifier 400 may include a first isolator 440.

It should be understood that in an amplifier or a system including an amplifier, since there may be other elements at the output end of the gain fiber, and even though the elements are tightly coupled to the connected gain fiber, there may be a case that part of light is reflected by the elements and re-enters the gain fiber, so a first optical isolator 440 may be disposed at the output end of the gain fiber, and may be used to isolate the reflected light from the output end of the gain fiber, so as to avoid that the reflected light enters the gain fiber to change key performance indexes such as noise index, and reduce adverse effects of the reflected light on the spectral output power stability of the light source.

Based on the scheme, the amplifier can isolate the influence of the reflected light of the output end on the amplification effect of the gain optical fiber, and improves the quality of output signal light.

Alternatively, the amplifier 400 may include a first isolator 440 and a second isolator 450.

It will be appreciated that in a fiber amplifier, random incoherent spontaneous emissions of excited particles are also produced as the excited particles return to the ground state from the excited state and amplify the optical signal. Such spontaneous radiation may be in any direction and may cause further stimulated radiation and may be amplified. In short, amplification in the non-signal band, ASE noise, will be generated during the amplification process. The ASE noise may leak from the input end of the gain fiber, affecting the performance of the front-end components. Thus, a second optical isolator 450 may be arranged at the input end of the gain fiber for isolating ASE noise from leakage at the input end of the gain fiber.

Based on the scheme, the reverse ASE noise of the gain optical fiber at the input end can be eliminated, the influence of the reflected light of the output end on the amplification effect of the gain optical fiber is isolated, and the working stability of the optical fiber amplifier and the quality of output signal light can be improved.

Fig. 5 shows a schematic diagram of an optical fiber amplifier 500 according to an embodiment of the present application, where the optical fiber amplifier 500 may be used to amplify L-band signal light.

In contrast to the amplifier 400 shown in fig. 4, in this amplifier 500, the combiner 530 is placed at but the output of its amplifying module 510. The combiner 530 inputs the C-band auxiliary light back from the output of the amplifying module 510.

Specifically, the light source 520 of the auxiliary light generates C-band auxiliary light, the C-band auxiliary light is input to the combiner 530 through an optical fiber, the combiner 530 inputs the received C-band auxiliary light to the EDF through an output optical fiber, the first WDM 511 optically couples the L-band input signal light and the pump light generated by the light source 513 of the pump light into third coupled signal light, and the third coupled signal light is input to the input end of the EDF 512 through the output optical fiber, and the EDF 512 amplifies the L-band input signal light by the pump light in the third coupled signal light to obtain amplified L-band output signal light.

In one implementation, as shown in fig. 5, the amplifier 500 may further include: first isolator 540 and/or second isolator 550.

It should be noted that the functions of the first isolator 540 and the second isolator 550 in the amplifier 500 may be correspondingly described with reference to fig. 4, and for brevity, the description is omitted herein.

In addition, in the embodiment of the present application, when the signal light is output along the transmission direction of the L-band, the combiner 530 should be located before the first isolator 540.

It should be understood that other elements of the amplifier 500 may be correspondingly described with reference to fig. 4, and for brevity, will not be described again here.

It will be appreciated that a single pump source is limited to the energy provided by the laser gain medium and often cannot meet the requirements of high power lasers. For this reason, the solution provided in the embodiments of the present application may be improved on the pumping manner, that is, a two-way pumping manner, for example, the laser 600 and the laser 700 shown in fig. 6 and 7. By designing the structure of the laser, the bidirectional pump is adopted to provide larger energy for the laser so as to obtain high-power laser output.

It should be noted that, the structure of the laser 600 shown in fig. 6 may be modified from that of the laser 400 shown in fig. 4, so for simplicity of illustration, other elements in the laser 600 may be correspondingly referred to the related description in fig. 4, and will not be repeated here. The laser 700 shown in fig. 7 may be an improvement on the structure of the laser 500 shown in fig. 5, so for simplicity of explanation, other elements in the laser 700 may be referred to in the related description of fig. 5 correspondingly, which is not repeated here.

Currently, in order to realize dynamic gain adjustment of an amplifier on amplified L-band output light, in the embodiment provided by the application, a C/L demultiplexer is introduced at an output end of the amplifier to filter out C-band wavelength light, and optical power is detected, and the optical power of C-band auxiliary light and/or the wavelength of C-band auxiliary light are adjusted by feedback to realize dynamic gain adjustment of L-band optical amplification. Based on the amplifiers shown in fig. 4 to 7, respectively, the embodiments of the present application provide the amplifier structures shown in fig. 8 to 11.

For simplicity of illustration, the dynamic gain adjustable L-band optical amplifier provided herein will be described with respect to amplifier 800 shown in fig. 8.

Fig. 8 shows a schematic diagram of an optical fiber amplifier 800 according to an embodiment of the present application, where the optical fiber amplifier 800 may be used to amplify L-band signal light.

In one implementation, as shown in fig. 8, the amplifier 800 may include:

a single stage amplification module 810, a light source 820 for auxiliary light, a combiner 830, a demultiplexer 860, and a Photodetector (PD) 870.

The single-stage amplifying module 810 is configured to receive the input signal light, and amplify the input signal light with the pump light to obtain output signal light.

A combiner 830 for coupling the auxiliary light into the amplifying module.

The demultiplexer 860 is configured to separate light to be measured in the C-band of the output signal light.

And the PD 870 is used for measuring the optical power of the C-band light to be measured.

A light source 820 of the auxiliary light for generating the auxiliary light while adjusting the wavelength of the auxiliary light and/or the optical power of the auxiliary light based on the optical power of the light to be measured.

The single stage amplification module 810 may include a first WDM811, an EDF812, and a source 813 of pump light, which source 813 may be 980nm or 1480nm laser pumping.

Specifically, the light source 820 of the auxiliary light generates C-band auxiliary light, which is input to the combiner 830 through an optical fiber, and the combiner 830 generates first coupling signal light from the received L-band input signal light and the C-band auxiliary light coupling, and inputs the first coupling signal light to the input end of the first WDM811 through an output optical fiber. The first WDM811 couples the pump light generated by the light source 813 of the first coupling signal light and the pump light into the second coupling signal light, and inputs the second coupling signal light to the input end of the EDF812 through the output optical fiber, and the EDF812 amplifies the L-band input signal light in the first coupling signal light by using the pump light in the second coupling signal light, thereby obtaining the amplified L-band output signal light. The output signal light of the L-band is transmitted to the input end of the demultiplexer 860 through an optical fiber, after the demultiplexer 860 receives the output signal, the output signal light is split into two paths according to the wavelength, one path is amplified L-band light, the output end of the amplifier 800 outputs the amplified L-band light, the other path is light to be measured of the C-band, the light is transmitted to the PD 870 through the optical fiber, the PD 870 detects the optical power of the light to be measured, and the detection result can be used for adjusting the wavelength and/or the power of the auxiliary light by the auxiliary light source.

For example, in one implementation manner, the corresponding relationship between the optical power of the light to be measured in the C-band and the gain of the output signal light in the L-band may be pre-stored in the PD 870, and the corresponding parameter setting is performed on the light source 820 of the auxiliary light in the C-band according to the corresponding relationship, so as to change the optical wavelength and/or the power of the output auxiliary light, so as to achieve the gain of the output signal light in the target L-band.

Alternatively, in another implementation manner, a threshold value of the optical power of the light to be measured in the C-band may be pre-stored in the PD 870, below which the gain of the L-band output signal light outputted by the amplifier 800 is indicated to be smaller, and at this time, the optical wavelength and/or the power of the outputted auxiliary light may be changed by setting the corresponding parameters of the light source 820 of the C-band auxiliary light, so as to achieve the gain of the target L-band output signal light. Of course, the opposite threshold mechanism may be set, for example, below the threshold, which indicates that the gain of the L-band output signal light output by the amplifier 800 is larger, where the optical wavelength and/or power of the output auxiliary light may be changed by setting the corresponding parameters of the light source 820 of the C-band auxiliary light, so as to achieve the gain of the target L-band output signal light.

It should be appreciated that the "preset" may include predefined, for example, by pre-storing corresponding codes, tables, or other means that may be used to indicate relevant information in the PD 870, and the present application is not limited to a specific implementation thereof.

The light source 820 of the auxiliary light may be a semiconductor light emitting diode, a laser diode, or a fiber laser.

Based on the scheme, the amplifier can inhibit the ASE of the C wave band by introducing the auxiliary light of the C wave band, so that the pumping efficiency of the L wave band optical amplifier is improved, and the gain performance of the L wave band optical amplifier is improved. Meanwhile, by utilizing the correlation between the C-band optical power and the L-band signal amplification gain, the dynamic gain adjustment of the L-band optical amplifier is realized by detecting the C-band optical power at the output end of the optical amplifier and feeding back and adjusting the power and/or the wavelength of the C-band auxiliary light.

Optionally, a filter 880 may be further included in the amplifier 800, where the filter 880 is configured to filter out the C-band spontaneous emission noise in the C-band light to be measured.

In another implementation, as shown in fig. 8, the amplifier 800 may further include:

a first isolator 840 and/or a second isolator 850.

The first isolator 840 is configured to isolate the reflected light from the output end of the gain fiber, so as to avoid the reflected light entering the gain fiber to change key performance indexes such as noise index, and reduce the adverse effect of the reflected light on the stability of the spectral output power of the light source.

The second isolator 850 is used to isolate ASE noise from the gain fiber input leakage.

It should be understood that fig. 9-11 are each structures with the feedback adjustment added to fig. 5-7, respectively, and for simplicity of illustration, the roles of the elements in fig. 9-11 may be referred to fig. 5-7, respectively, and the description thereof with reference to fig. 8 is omitted herein.

Fig. 12 shows a schematic diagram of a fiber amplifier 1200 according to an embodiment of the present application, where the fiber amplifier 1200 may be used for multi-stage amplification of L-band signal light and/or for optical dynamic gain adjustment of L-wave Duan Xinhao.

It should be appreciated that the amplifier 1200 shown in fig. 12 may be implemented as a cascade of multi-stage high pumping efficiency L-band optical amplifiers based on the structure of the amplifier 400 shown in fig. 4 or the structure of the amplifier 500 shown in fig. 5 or the structure of the amplifier 600 shown in fig. 6 or the structure of the amplifier 700 shown in fig. 7.

Alternatively, the amplifier 1200 shown in fig. 12 may be a cascaded L-band dynamic optical power tunable optical amplifier with multiple stages of high pumping efficiency based on the structure of the amplifier 800 shown in fig. 8 or the structure of the amplifier 900 shown in fig. 9 or the structure of the amplifier 1000 shown in fig. 10 or the structure of the amplifier 1100 shown in fig. 11.

In one implementation, a gain flattening filter may be introduced between each stage of amplification modules of the amplifier 1200, or a variable optical attenuator may adjust the gain spectrum.

With respect to the embodiments of fig. 4 to 12, it should be noted that:

(1) The numbers of the elements or modules or structures described in the embodiments are only examples, and do not limit the application, and some elements or modules or structures may be added or deleted on the basis of the respective structural diagrams according to actual needs in the embodiments of the application.

(2) The embodiments of fig. 4 to 12 described above may be implemented independently or may be combined with each other, for example, the embodiment of fig. 4 and the embodiment of fig. 12 are combined with each other, the embodiment of fig. 5 and the embodiment of fig. 12 are combined with each other, and so on.

Those of ordinary skill in the art will appreciate that the steps of the examples described in connection with the embodiments disclosed herein can be implemented as electronic hardware, or as a combination of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It will be clear to those skilled in the art that, for convenience and brevity, the specific working procedures of the above-described method may refer to the corresponding procedures in the foregoing apparatus embodiments, which are not described herein again

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof.

When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in accordance with embodiments of the present application are produced in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. For example, the computer may be a personal computer, a server, or a network device, etc. The computer instructions may be stored in or transmitted from one computer-readable storage medium to another, for example, by wired (e.g., coaxial cable, fiber optic, digital Subscriber Line (DSL)), or wireless (e.g., infrared, wireless, microwave, etc.) means from one website, computer, server, or data center. With respect to computer readable storage media, reference may be made to the description above.

The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions easily conceivable by those skilled in the art within the technical scope of the present application should be covered in the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims and the specification.

Claims

1. An amplifier, comprising: at least one amplifying module, at least one light source for auxiliary light, and at least one combiner,

the amplifying module is used for receiving input signal light and amplifying the input signal light by using pump light to obtain output signal light, wherein the input signal light is L-band signal light;

the light source of the auxiliary light is used for generating auxiliary light, the wavelength of the auxiliary light is in a C wave band, the optical power of the auxiliary light is smaller than the optical power of the input signal light, and the optical power of the auxiliary light is smaller than the optical power of the pumping light;

the combiner is used for coupling the auxiliary light into the amplifying module.

2. The amplifier of claim 1, wherein the amplifier further comprises: a demultiplexer and an optical detector,

the wave separator is used for separating light to be measured in the output signal light, and the wavelength of the light to be measured is C wave band;

the light detector is used for measuring the light power of the light to be measured;

the light source of the auxiliary light adjusts the wavelength of the auxiliary light and/or the optical power of the auxiliary light based on the optical power of the light to be measured.

3. The amplifier of claim 2, wherein the amplifier further comprises:

and the filter is used for filtering the C-band spontaneous emission noise in the light to be measured.

4. An amplifier according to any one of claims 1 to 3, wherein the amplifying module comprises: wavelength division multiplexer, light source of pump light, gain fiber,

the wavelength division multiplexer is used for coupling the pumping light into the gain optical fiber;

the light source of the pump light is used for generating the pump light;

the gain fiber amplifies the input signal light by using the pump light, and the gain fiber is an erbium-doped fiber.

5. An amplifier according to any one of claims 1 to 4, characterized in that,

the wavelength of the pump light is smaller than that of the C-band signal light, and the wavelength of the pump light is 980nm or 1480nm.

6. An amplifier according to any one of claims 1 to 5, characterized in that,

the wave combiner is arranged at the input end of the amplifying module and is also used for coupling the input light with the auxiliary light to generate first coupling signal light,

the combiner is configured to couple the auxiliary light into the amplifying module, and includes:

the combiner is used for coupling the first coupling signal light into the amplifying module.

7. An amplifier according to any one of claims 1 to 5, characterized in that,

the wave combiner is arranged at the output end of the amplifying module.

8. An optical fiber communication system, comprising:

an optical amplification station comprising the optical fiber amplifier of any one of claims 1-7 for amplifying the input signal light.