Method, apparatus, optical amplifier and storage medium for gain compensation

Abstract

The application provides a gain compensation method, device, optical amplifier and storage medium, and belongs to the technical field of optical communication. The method is applied to an optical amplifier. In the method, after the power of input signal light changes, the power of pump light of the optical amplifier is adjusted based on power change information of the input signal light, the input signal light is amplified by using the pump light with the adjusted power, and the input signal light is gain compensated. In this way, the input signal light can be gain compensated only by detecting the power change information of the input signal light, the optical amplifier does not need to be in a full wave state for a long time, and therefore, the failure rate of the optical amplifier can be reduced.

Description

Technical Field

[0001] This application relates to the field of optical communication technology, and in particular to a method, apparatus, optical amplifier, and storage medium for gain compensation. Background Technology

[0002] With the rapid development of emerging services and applications such as the Internet of Things (IoT), artificial intelligence (AI), and augmented reality (AR), the amount of data that needs to be transmitted is increasing dramatically. Therefore, optical communication networks need to provide network transmission services with greater bandwidth and higher speeds. To provide this network transmission service, optical communication networks need to offer more stable and flexible wavelength-level intelligent service scheduling capabilities. During wavelength-level service scheduling, there may be instances where the number of service wavelengths decreases or increases, which can cause dynamic changes in the gain of the signal light, potentially leading to service interruptions.

[0003] In related technologies, to reduce the impact of reducing or increasing service wavelengths on gain, after reducing a certain service wavelength, a "dummy optical signal" of that service wavelength is input to the optical amplifier. This ensures that the wavelength combination of the input signal light to the optical amplifier remains unchanged, meaning the optical amplifier is always in full-wavelength mode. While this reduces the impact on gain, it keeps the optical amplifier in full-wavelength mode for extended periods, potentially leading to a higher failure rate. Summary of the Invention

[0004] This application provides a method, apparatus, optical amplifier, and storage medium for gain compensation, which can reduce the failure rate of the optical amplifier and extend its service life. The technical solution adopted is as follows:

[0005] In a first aspect, this application provides a gain compensation method applied to an optical amplifier. The method includes: adjusting the power of the pump light of the optical amplifier based on power change information of the input signal light, wherein the power change information includes the amount of power change and / or the power before and after the power change; and amplifying the input signal light based on the power-adjusted pump light to perform gain compensation on the input signal light.

[0006] In the scheme shown in this application, the power of the pump light is adjusted using the power change information of the input signal light to compensate for the gain of the input signal light. Thus, gain compensation for the input signal light can be performed simply by detecting the power change information, reducing the impact of gain on gain caused by adding or removing wavelengths. This eliminates the need for the optical amplifier to operate at full wavelength for extended periods, thereby reducing the failure rate of the optical amplifier and extending its lifespan.

[0007] In one alternative approach, when adjusting the power of the pump light of an optical amplifier, one scheme uses power change information to determine the gain compensation amount of the input signal light, and then uses this gain compensation amount to adjust the power of the pump light of the optical amplifier. This way, by first determining the gain compensation amount and then adjusting the pump light power, compensation can be performed according to the gain compensation amount. In another scheme, power change information is used to determine a first gain of the input signal light, which is the gain obtained after gain compensation of the input signal light, and then the power of the pump light of the optical amplifier is adjusted using this first gain. This way, by first determining the gain after gain compensation and then adjusting the pump light power, the power of the pump light can be directly adjusted according to the desired gain.

[0008] In one alternative approach, when gain compensation is performed using a gain compensation amount, this amount is based on a second gain. Before amplifying the input signal light based on the power-adjusted pump light, the target power of the pump light of the optical amplifier is determined using the second gain. The input signal light is then amplified using the pump light at the target power, so that the gain of the input signal light is equal to the second gain. Then, the power of the pump light of the optical amplifier is adjusted based on the target power. In this way, the gain of the input signal light is locked at the second gain, and when adjusting the power of the pump light, adjustments are made based on the second gain, allowing for accurate adjustment of the pump light power.

[0009] In one alternative approach, after determining the arrival of the compensation time point, the input signal light is amplified based on the power-adjusted pump light. This compensation time point is the time delay after a power overshoot of the output signal light, where the power overshoot includes the output signal light reaching its maximum or minimum power. Thus, performing gain compensation after the power overshoot of the output signal light reduces the possibility of overcompensation.

[0010] In one alternative approach, the optical amplifier is an integrated amplification optical amplifier, which includes an optical amplification module that amplifies the input signal light based on the power-adjusted pump light. This allows for gain compensation after adding or removing the signal, ensuring that the signal light operates within its normal power range after either process.

[0011] In one alternative approach, the optical amplifier is a wavelength-division amplification optical amplifier, comprising multiple optical amplification modules. Different optical amplification modules are used to amplify signal light in different wavelength bands. When adjusting the pump light power of the optical amplifier, the pump light power of the target optical amplification module corresponding to the target wavelength band is adjusted based on the power change information of the signal light in the target wavelength band. The target wavelength band is the band to which the power of the input signal light changes. Then, based on the power-adjusted pump light, the target optical amplification module is controlled to amplify the signal light in the target wavelength band to perform gain compensation. In this way, since the wavelengths within the same band are closer, the gain compensation amounts are also closer. By adjusting the pump light power of the corresponding optical amplification module based on the power change information of each band, and performing gain compensation band-by-band, the compensation effect is better.

[0012] In one alternative approach, the optical amplifier is a partially integrated optical amplifier, comprising a first optical amplification module and multiple second optical amplification modules. The first optical amplification module is an integrated amplification module, and different second optical amplification modules are used to amplify signal light in different wavelength bands. When adjusting the power of the pump light of the optical amplifier, the power of the first pump light of the first optical amplification module is adjusted using the power change information of the input signal light, and the power of the second pump light of at least one second optical amplification module is also adjusted, as the power of the signal light amplified by this at least one second optical amplification module varies. Then, based on the power-adjusted first pump light, the first optical amplification module is controlled to amplify the input signal light to perform overall gain compensation. Similarly, based on the power-adjusted second pump light, the at least one second optical amplification module is controlled to amplify the received signal light to perform gain compensation. This approach first performs overall gain compensation on the input signal light, and then performs gain compensation in different wavelength bands. When overall gain compensation is insufficient, band-specific gain compensation is performed, resulting in more accurate gain compensation and a better compensation effect.

[0013] In one alternative approach, when adjusting the power of the second pump light of at least one second optical amplification module based on power change information, power change information of the target band in the input signal light can be obtained. Then, based on this power change information, the power of the second pump light of the second optical amplification module corresponding to the target band can be adjusted, thereby determining the accurate power of the second pump light.

[0014] Alternatively, the power change information of the input signal light and the gain allocation ratio of multiple second optical amplification modules can be used to adjust the power of the second pump light of at least one second optical amplification module. Since there is no need to detect the power change information of each band in the input signal light, the structure of the optical amplifier is relatively simple and the power of the second pump light can be obtained more quickly.

[0015] In one alternative approach, when performing gain compensation for the entire input signal light or for specific wavelengths, the optimal gain compensation amount may differ. Therefore, gain correction can be performed wavelength-specifically. The optical amplifier also includes a dynamic gain flattening filter (DGFF). Based on the power variation information of the input signal light, the gain correction amount for each wavelength of the input signal light is determined. The DGFF is then controlled to use this gain correction amount to perform gain correction processing on the amplified signal light of each wavelength. This allows for individual gain correction for each wavelength, ensuring that the signal light power remains within the normal power range after adding or removing wavelengths.

[0016] In one alternative approach, when the power change of the input signal light exceeds a target threshold, the power of the pump light of the optical amplifier is adjusted using the power change information of the input signal light, so that gain compensation is performed when the power change is relatively large, so that the power of the signal light is within the normal power range.

[0017] In one alternative approach, an optical amplifier is applied to the optical multiplexing section so that the power of the signal light in the optical multiplexing section remains within the normal power range after adding or dropping the wavelength.

[0018] Secondly, this application provides a gain compensation apparatus that has the function of implementing the first aspect or any optional method of the first aspect described above. The apparatus includes at least one module for implementing the method provided by the first aspect or any optional method of the first aspect.

[0019] Thirdly, this application provides an optical amplifier, which includes a processor, a memory, and a communication interface. The processor is used to execute program instructions in the memory to implement the method provided in the first aspect or any optional method of the first aspect. The communication interface is used to connect to an optical fiber.

[0020] Fourthly, this application provides a computer-readable storage medium storing at least one program instruction that is read by a processor to cause an optical amplifier to perform the method provided in the first aspect or any alternative method of the first aspect.

[0021] Fifthly, this application provides a computer program product including program instructions stored in a computer-readable storage medium. A processor of an optical amplifier reads the program instructions from the computer-readable storage medium and executes the program instructions, causing the optical amplifier to perform the method provided in the first aspect or any optional method of the first aspect. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the architecture of an optical transmission system provided in an exemplary embodiment of this application;

[0023] Figure 2 This is a schematic diagram illustrating the principle of gain compensation provided in an exemplary embodiment of this application;

[0024] Figure 3 This is a schematic flowchart of a gain compensation method provided in an exemplary embodiment of this application;

[0025] Figure 4 This is a schematic diagram of a wave drop in an optical transmission system provided in an exemplary embodiment of this application;

[0026] Figure 5 This is a schematic diagram illustrating the relationship between the power of the signal light, the power of the pump light, and time, provided in an exemplary embodiment of this application.

[0027] Figure 6 This is a schematic diagram of a first structure of an optical amplifier provided in an exemplary embodiment of this application;

[0028] Figure 7 This is a schematic flowchart of an integrated amplification gain compensation method provided in an exemplary embodiment of this application;

[0029] Figure 8 This is a schematic diagram of a second structure of an optical amplifier provided in an exemplary embodiment of this application;

[0030] Figure 9 This is a schematic flowchart of a gain compensation method for bandgap amplification provided in an exemplary embodiment of this application;

[0031] Figure 10 This is a schematic diagram of a third structure of an optical amplifier provided in an exemplary embodiment of this application;

[0032] Figure 11 This is a schematic diagram of a fourth structure of an optical amplifier provided in an exemplary embodiment of this application;

[0033] Figure 12 This is a schematic flowchart of a partially integrated amplification gain compensation method provided in an exemplary embodiment of this application;

[0034] Figure 13 This is a schematic diagram of a fifth structure of an optical amplifier provided in an exemplary embodiment of this application;

[0035] Figure 14 This is a schematic flowchart of a gain compensation and gain correction method provided in an exemplary embodiment of this application;

[0036] Figure 15 This is a schematic diagram illustrating the relationship between wavelength and gain compensation amount provided in an exemplary embodiment of this application;

[0037] Figure 16 This is a schematic diagram of a gain compensation device provided in an exemplary embodiment of this application. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0039] With the rapid development of emerging services and applications such as the Internet of Things (IoT), AR, virtual reality (VR), and AI, people are pursuing network transmission services with greater bandwidth and higher speeds. Therefore, optical communication networks need to provide more stable and flexible intelligent wavelength-level service scheduling solutions. However, during the addition of new services and service scheduling, wavelength addition and / or wavelength drop can occur. Wavelength addition refers to adding at least one wavelength of service signal light during optical signal transmission, while wavelength drop refers to reducing at least one wavelength of service signal light during optical signal transmission. For example, wavelength addition occurs when adding a new service, and wavelength drop occurs when a service is scheduled to be transmitted through another path.

[0040] In optical signal transmission, to ensure the power of the optical signal, optical amplifiers are typically placed along the transmission path. These amplifiers determine the pump light power based on the power of the input signal light. After adding or removing the signal, the amplifier identifies the input signal light power and adjusts the pump light power, causing a change in the population inversion rate. This results in a significant change in the gain spectrum of the amplifier, leading to gain competition and dynamic changes in the amplifier's gain, potentially causing service interruption. Furthermore, when the amplifier is a doped fiber amplifier, the inherent spectral hole-burning characteristic of doped fibers causes coupling changes in the gain of the remaining signal light after adding or removing the signal, making it impossible to maintain stability. In addition, due to the inherent stimulated Raman scattering (SRS) effect of the transmission fiber, energy transfer occurs between short-wavelength and long-wavelength service signal light during long-distance transmission. Generally, during wavelength addition, the energy of the short-wavelength service signal light is transferred to the long-wavelength service signal light; conversely, during wavelength drop, the energy of the long-wavelength service signal light is transferred to the short-wavelength service signal light. Therefore, during wavelength addition, the loss of the transmission fiber increases at short wavelengths, and during wavelength drop, the loss of the transmission fiber increases at long wavelengths. Furthermore, as optical communication networks smoothly upgrade from the conventional (C) band to the C+ long (L) band, the wavelength range expands to 100nm, and stimulated Raman scattering becomes increasingly intense and complex, leading to more severe system fluctuations caused by wavelength addition or drop.

[0041] To reduce system fluctuations caused by adding or dropping wavelengths, an amplified spontaneous emission (ASE) source is typically placed before the wavelength selective switch (WSS). The ASE source outputs dummy light at the dropped wavelength, which is then fed into the optical amplifier along with the signal light by the WSS. This ensures that the wavelength combination of the signal light input to the optical amplifier remains unchanged, meaning the optical amplifier is always in a full-wavelength state. ASE sources are generally expensive and bulky, occupying significant physical space. Furthermore, the fact that the optical amplifier is constantly in a full-wavelength state results in a high failure rate.

[0042] Based on this, embodiments of this application provide a gain compensation method. After detecting a change in the power of the input signal light, the power of the pump light of the optical amplifier is adjusted based on the power change information. The input signal light is then amplified using the power-adjusted pump light to compensate for its gain. This eliminates the need for dummy light to compensate for the gain, thereby reducing the failure rate of the optical amplifier, extending its lifespan. Furthermore, it eliminates the need for an ASE light source, thus reducing the cost and size of the optical amplifier.

[0043] The gain compensation method of this application embodiment is applicable to various optical transmission systems employing optical amplifiers, including but not limited to rare-earth-doped optical amplifiers and semiconductor optical amplifiers. The gain medium of rare-earth-doped optical amplifiers includes, but is not limited to, erbium-doped fiber and bismuth-doped fiber. The wavelength range of the optical transmission system includes, but is not limited to, original (O), extended (E), short (S), C, L, and ultra-long (U) bands.

[0044] This optical transmission system can be applied to long-distance, high-capacity, and high-speed optical fiber communication systems (such as optical transport networks (OTN)), access networks, and optical fiber cable television (CATV) networks. The optical amplifier can be used as a power amplifier, repeater amplifier, or preamplifier in this optical transmission system. Typically, the power amplifier is located near the transmitting end, the repeater amplifier is located at the intermediate transmission position of the signal light, and the preamplifier is located near the receiving end.

[0045] Optionally, the optical transmission system includes at least one optical multiplex section (OMS), see [link to documentation]. Figure 1 .like Figure 1 As shown, each OMS includes two multiplexing / demultiplexing modules, two optical amplifiers, and a transmission fiber. The two optical amplifiers and the transmission fiber are located between the two multiplexing / demultiplexing modules, and the transmission fiber is located between the two optical amplifiers. The multiplexing / demultiplexing module can be a WSS. Optionally, in the optical transmission system, adjacent multiplexing / demultiplexing modules belong to a reconfigurable optical add-drop multiplexer (ROADM) or an optical cross node.

[0046] The principle and process of gain compensation are described below. The principle is as follows: by detecting the power change information of the input signal light, the power of the signal light that was originally outside the normal range is compensated to the normal range, while the power of the signal light that was originally within the normal range is also kept within the normal range.

[0047] Gain compensation process: such as Figure 2 As shown, the optical amplifier detects the power of both the input and output signal light. Then, using the power change information of the input signal light, the optical amplifier adjusts its pump light to compensate for the gain of the input signal light. Finally, it uses the power of the output signal light to determine whether the gain of the input signal light has reached the specified gain.

[0048] The following describes the gain compensation method flow in the embodiments of this application. Figure 3 A method flow for gain compensation is provided, see steps 301 to 302. The execution entity of this method is a gain compensation device, which can be a hardware device, such as an optical amplifier, or a software program deployed on that hardware device. In the embodiments of this application, in... Figure 3 The solution will be explained in detail using an optical amplifier as the implementing entity.

[0049] Step 301: Based on the power change information of the input signal light, adjust the power of the pump light of the optical amplifier, wherein the power change information includes the amount of power change and / or the power before and after the power change.

[0050] In this embodiment, the input signal light is the signal light input to the optical amplifier. This input signal light is generally a wavelength division multiplexed optical signal, meaning it includes signal light with multiple wavelengths. In some cases, the input signal light may also be a single-wavelength signal light. After the optical amplifier detects a change in the power of the input signal light, or determines that wavelength addition or loss has occurred, it acquires the power change information of the input signal light. This power change information includes the amount of power change and / or the power before and after the power change. The optical amplifier uses this power change information to adjust the power of its pump light.

[0051] In one alternative approach, the optical amplifier can first determine the gain compensation amount and then adjust the power of the pump light, as follows:

[0052] The optical amplifier uses power change information to determine the gain compensation amount for the input signal light. This gain compensation amount is then used to adjust the power of the pump light in the optical amplifier.

[0053] Optionally, when the power change information includes the amount of power change, the optical amplifier stores a correspondence between the range of power changes and the gain compensation amount. The optical amplifier determines the range of power changes to which the power change belongs based on this correspondence, and then determines the corresponding gain compensation amount, which is the gain compensation amount for the input signal light. This correspondence can be obtained through experimental simulation calculations. For example, by simulating various combinations of added and / or dropped signals, the correspondence with the best gain compensation effect is obtained. The criterion for a good gain compensation effect is: ensuring that the signal light operates within the normal range, that is, compensating the power of the signal light outside the normal range to the normal range, while simultaneously ensuring that the power of the signal light within the normal range remains within the normal range.

[0054] Alternatively, the optical amplifier stores a first deterministic model of the gain compensation amount. The power change is input into this first deterministic model, which then outputs the gain compensation amount of the input signal light. This first deterministic model can be a formula, where the power change is the variable.

[0055] Optionally, if the power change information includes the power before and after the power change, the optical amplifier determines the difference in power before and after the power change to obtain the power change amount. Then, the optical amplifier can find the gain compensation amount in the correspondence between the power change amount range and the gain compensation amount.

[0056] Alternatively, the optical amplifier stores a second deterministic model of the gain compensation amount. The power before and after the power change is input into the second deterministic model, which then outputs the gain compensation amount of the input signal light. The second deterministic model can be a formula, where the variables are the power before and after the power change.

[0057] When the power change information includes both the amount of power change and the power before and after the change, the optical amplifier stores a third determination model for the gain compensation. The amount of power change and the power before and after the change are input into this third determination model, which then outputs the gain compensation amount of the input signal light. This third determination model can be a formula, where the variables are the amount of power change and the power before and after the change.

[0058] It should be noted that the first, second, and third deterministic models can be established based on experience as initial models. Then, by combining various signal addition and / or signal drop scenarios, the initial models are corrected through simulation to obtain the final model. This final model ensures that the power of signal light outside the normal range is compensated to the normal range, and the power of signal light within the normal range remains within the normal range.

[0059] After determining the gain compensation amount, the correspondence between the gain compensation range and the power adjustment amount is used to determine the gain compensation range to which the gain compensation amount belongs, and then the corresponding power adjustment amount is determined. The power adjustment amount is added to the current power of the pump light to obtain the adjusted power of the pump light. Here, the power adjustment amount may be negative or positive.

[0060] In another alternative approach, the optical amplifier can directly determine the gain after gain compensation, and then use this gain to adjust the power of the pump light, as follows:

[0061] Optionally, when the power change information includes the amount of power change, the optical amplifier stores a correspondence between the range of power changes and a first gain. The optical amplifier determines the range of power changes to which the power change belongs based on this correspondence, and then determines the first gain corresponding to the power change. This first gain is the gain obtained after gain compensation of the input signal light. This correspondence can be obtained through experimental simulation calculations. For example, various combinations of added and / or dropped signals are simulated to obtain the correspondence with the best gain compensation effect.

[0062] Alternatively, the optical amplifier stores a fourth deterministic model of the first gain. The power change is input into the fourth deterministic model, and the first deterministic model outputs the first gain of the input signal light. The fourth deterministic model can be a formula, where the variable is the power change.

[0063] Optionally, if the power change information includes the power before and after the power change, the optical amplifier determines the difference in power before and after the power change to obtain the power change amount. Then, the optical amplifier can find the first gain in the correspondence between the power change range and the first gain.

[0064] Alternatively, the optical amplifier stores a fifth determining model of the first gain. The power before and after the power change is input into the fifth determining model, and the fifth determining model outputs the first gain of the input signal light. The fifth determining model can be a formula, where the variable is the power before and after the power change.

[0065] When the power change information includes the amount of power change and the power before and after the power change, the optical amplifier stores a sixth determining model for the first gain. The amount of power change and the power before and after the power change are input into the sixth determining model, and the sixth determining model outputs the first gain of the input signal light. The sixth determining model can be a formula, where the variables are the amount of power change and the power before and after the power change.

[0066] It should be noted that the fourth, fifth, and sixth deterministic models can be established based on experience as initial models. Then, by combining various wave-addition and / or wave-drop scenarios, the initial models are corrected through simulation to obtain the final models.

[0067] After determining the first gain, the corresponding relationship between the gain range and the power of the pump light is used to determine the gain range to which the first gain belongs. Then, the power of the pump light corresponding to the gain range is determined. This power is the power of the pump light after power adjustment.

[0068] In one alternative approach, when adjusting the pump light power using gain compensation, this gain compensation is based on a second gain. This means that the determination of the correspondence between power change and gain compensation was also based on the second gain, which can be a fixed gain, set empirically, or the gain the input signal light was originally required to achieve. Before step 302, the optical amplifier performs gain locking to ensure the input signal light gain is the second gain. The gain locking process is as follows: the optical amplifier uses the difference between the output signal light power (in dBm) and the input signal light power (in dBm) to determine the current gain of the input signal light, and then compares this current gain with the second gain. If the current gain is greater than the second gain, the pump light power is reduced, and this output signal light becomes the output signal light of the optical amplifier. The input signal light is amplified to obtain the output signal light. After reducing the pump light power, the relationship between the current gain and the second gain of the input signal light is determined. If the current gain is not the second gain but is still greater than it, the pump light power is further reduced; otherwise, the pump light power is increased until the current gain of the input signal light is close to or equal to the second gain, thus obtaining the target power. The target power is the pump light power of the optical amplifier. "Close to" means the difference between the current gain and the second gain is less than a certain value, which is relatively small. Then, the optical amplifier uses the pump light at the target power to amplify the input signal light, ensuring that the gain of the input signal light is equal to the second gain. When adjusting the pump light power using power change information, the optical amplifier adjusts the pump light power based on the target power.

[0069] Alternatively, if the power of the pump light is adjusted using a gain compensation amount, which is a compensation amount based on the current gain, then the current gain is also considered when calculating the gain compensation amount.

[0070] In one alternative approach, when the power variation of the input signal light exceeds a target threshold, the power of the pump light of the optical amplifier is adjusted using the power variation information of the input signal light. This allows for gain compensation when the power variation is significant, ensuring the signal light power remains within the normal range. By only performing gain compensation on signal light with large fluctuations, processing resources can be saved. Of course, embodiments of this application can also adjust the power of the pump light of the optical amplifier when the power variation of the input signal light is small; this application is not limited to this approach.

[0071] Step 302: Based on the pump light with adjusted power, the input signal light is amplified to compensate for the gain of the input signal light.

[0072] In this embodiment, the optical amplifier uses pump light with adjusted power to amplify the input signal light. The optical amplifier determines whether the gain compensation level has been reached. If the gain compensation level has been reached, the current power is used to continue amplifying the input signal light. If the gain compensation level has not been reached, the power of the pump light is fine-tuned again until the gain compensation level is reached. Alternatively, the optical amplifier determines whether a first gain has been reached. If the first gain has been reached, the current power is used to continue amplifying the input signal light. If the first gain has not been reached, the power of the pump light is fine-tuned again until the gain reaches the first gain. Here, it is possible that the specified gain cannot be adjusted to the specified gain (which is either the first gain or the second gain plus the gain compensation level; generally, the first gain equals the second gain plus the gain compensation level) in one adjustment. Therefore, the power of the pump light can be fine-tuned further.

[0073] In one alternative approach, gain compensation is performed after gain overshoot to avoid large instantaneous power fluctuations during gain gain or loss, which could lead to strong nonlinear effects. Therefore, before step 302, a compensation time point is determined; this compensation time point is the time delay of the target duration after the power overshoot of the output signal light. At or after this compensation time point, the optical amplifier amplifies the input signal light based on the power-adjusted pump light. For example, for… Figure 1 The optical transmission system shown, such as Figure 4 As shown, after the fiber transmitting 29 wavelengths is broken, the signal light transmitting 30 wavelengths is reduced to transmitting only 1 wavelength. This is in response to... Figure 4 , Figure 5It also provides a schematic diagram of the pump light power, time, and output signal light power. The horizontal axis represents time, the left vertical axis represents the output signal light power, and the right vertical axis represents the pump light power. The power unit here is RU, a relative unit used to express the proportion of a measured value relative to a standard or reference value. The dashed line indicates the power change of the signal light at one wavelength, and the solid line indicates the power change of the pump light. Figure 5 As can be seen, after the wave drop, the gain compensation scheme of this application stabilizes the power of the signal light at that wavelength. Furthermore, since the pump light is still the same as before the wave drop at time t1, the gain of the input signal light increases significantly. Performing gain compensation at this time might lead to overcompensation. Figure 5 In the process, at the gain compensation time point t0, between t1 and t0, the power of the pump light decreases because the optical amplifier detects that the gain of the input signal light increases (i.e., the power of the output signal light increases), thus reducing the gain of the pump light. After t0, the power of the pump light fluctuates because it may not be possible to adjust to the specified gain immediately, so repeated adjustments are required.

[0074] It should be noted that, Figure 5 This is just one example of gain compensation after overshoot. The shape of the curve indicates the trend of change. Under different environmental conditions and different wavelength combinations, the detected curve shape may be the same, but the values ​​of the points on the curve may be different.

[0075] Optionally, the target duration can be an empirical value or a duration determined through simulation calculations, ensuring that there is no gain overcompensation. Moreover, to enable timely compensation, it is generally set to be relatively short.

[0076] The gain compensation process for four types of optical amplifiers is described below.

[0077] In this embodiment, the optical amplifier may be an integrated amplification optical amplifier, a wavelength-division amplification optical amplifier, a partially integrated amplification optical amplifier, or an optical amplifier including a DGFF. Specifically, an integrated amplification optical amplifier amplifies the input signal light as a whole, a wavelength-division amplification optical amplifier amplifies the signal light in separate wavelengths, and a partially integrated amplification optical amplifier amplifies both the input signal light as a whole and in separate wavelengths. The wavelengths can include O-band, E-band, S-band, C-band, L-band, or U-band, or combinations of these bands. Different optical amplifier structures may lead to different gain compensation methods, which will be described below. For ease of description, the following explanation uses gain locking followed by gain compensation as an example. Furthermore, gain compensation can be performed after the gain overshoot of the output signal light.

[0078] 1. The optical amplifier is an integrated optical amplifier.

[0079] This optical amplifier is used to amplify signal light in a single band, or to amplify signal light in multiple bands. For example, a single band may be O-band, E-band, S-band, C-band, L-band, or U-band. Multiple bands may include C+L band or E+S band, etc. Figure 6 As shown, the optical amplifier includes an input beam splitter module, an input detection module, an optical amplification module, an output beam splitter module, an output detection module, and a pump control module. The input terminal of the optical amplifier is connected to the input interface of the input beam splitter module. One output interface of the input beam splitter module is connected to the input interface of the optical amplification module, and the other output interface is connected to the optical interface of the input detection module. The electrical interface of the input detection module is electrically connected to the pump control module. The output interface of the optical amplification module is connected to the input interface of the output beam splitter module, and the electrical interface of the optical amplification module is electrically connected to the pump control module. One output interface of the output beam splitter module is connected to the optical interface of the output detection module, and the other output interface is connected to the output terminal of the optical amplifier. The electrical interface of the output detection module is electrically connected to the pump control module. Figure 6 In this system, the optical interfaces are connected via optical fibers.

[0080] The input beam splitter divides the input signal light into two parts based on power. One part is input to the optical amplifier module, and the other part is input to the input detection module. The input detection module performs photoelectric conversion on the received signal light to obtain a first electrical signal, which is then output to the pump control module. The optical amplifier module amplifies the received signal light and outputs the amplified signal light to the output beam splitter. The output beam splitter divides the received signal light into two parts based on power. One part is input to the output of the optical amplifier, and the other part is input to the output detection module. The output detection module performs photoelectric conversion on the received signal light to obtain a second electrical signal, which is then output to the pump control module. The pump control module uses the first and second electrical signals to determine whether the gain has reached the specified gain, and uses multiple detected first electrical signals to determine whether the power of the input signal light has changed. The splitting ratio of the input and output beam splitters is set according to actual needs. For example, in a splitting ratio of 1:99, the 1:99 portion is used to adjust the pump light, while the 99:99 portion continues transmission.

[0081] Optionally, in Figure 6 In this system, the optical amplification module can achieve single-stage amplification as well as multi-stage amplification.

[0082] See the gain compensation process. Figure 7 Steps 701 to 707.

[0083] Step 701: The pump control module determines the power change information of the input signal light.

[0084] In this embodiment, the pump control module uses the power of the first electrical signal detected in two consecutive steps to obtain the power change information.

[0085] Step 702: The pump control module adjusts the power of the pump light of the optical amplifier module to lock the gain.

[0086] In this embodiment, the pump control module acquires the second gain and adjusts the power of the pump light so that the gain of the input signal light is the second gain. In this way, the gain of the input signal light is locked to the second gain, or, to put it another way, the gain of the optical amplifier is locked to the second gain.

[0087] Step 703: The pump control module uses the power change information to adjust the power of the pump light of the optical amplification module.

[0088] The processing procedure for step 703 is described in step 301 and will not be repeated here.

[0089] In step 704, the pump control module sends a control signal to the optical amplification module, indicating the power of the pump light after power adjustment. The optical amplification module uses the power-adjusted pump light to amplify the input signal light to perform gain compensation.

[0090] In this embodiment, the pump control module sends a control signal to the optical amplification module. This control signal can be either current or voltage. After receiving the control signal, the optical amplification module determines the power of the pump light after power adjustment, outputs pump light of that power, and amplifies the input signal light to perform gain compensation.

[0091] Step 705: The pump control module determines whether the gain of the input signal light has reached the specified gain, which is the second gain plus the gain compensation amount.

[0092] In this embodiment, the pump control module acquires the first power of the output signal light and the second power of the input signal light, with the units of the first and second powers being dBm. The difference between the first and second powers is determined, and this difference is the gain of the input signal light. The pump control module then determines whether this gain reaches a specified gain.

[0093] Step 706: If the specified gain is not achieved, the pump control module fine-tunes the power of the pump light.

[0094] In this embodiment, if the gain does not reach the specified gain, the pump control module continues to fine-tune the power of the pump light of the optical amplification module until the gain of the input signal light reaches the specified gain.

[0095] Step 707: If the specified gain is reached, the pump control module ends the adjustment of the pump light power and inputs the currently used control signal to the optical amplification module.

[0096] 2. The optical amplifier is a wavelength-division amplification optical amplifier.

[0097] An optical amplifier includes multiple optical amplification modules, each used to amplify signal light in a different wavelength band. For example, if the input signal light includes C-band and L-band signal light, the optical amplifier includes two optical amplification modules: one for amplifying the C-band signal light and the other for amplifying the L-band signal light.

[0098] like Figure 8As shown, the optical amplifier includes multiple optical amplification components, a demultiplexer, a multiplexer, and a pump control module. Different optical amplification components are used to amplify signal light in different wavelength bands. Each optical amplification component includes an input splitter module, an input detection module, an optical amplification module, an output splitter module, and an output detection module. The input splitter module is connected to the multiplexer via optical fiber, and the output splitter module is also connected to the multiplexer via optical fiber. The connection methods of each module within the optical amplification component are described in [reference needed]. Figure 6 The description in [the document] describes a wavelength division multiplexing (WDM) system. A WDM is used to split an input signal light into multiple wavelength bands, which are then fed into optical amplification components corresponding to their respective bands. Each optical amplification component amplifies the received signal light and outputs the amplified signal to a multiplexer. The multiplexer combines the received signal light into a single beam for output. Figure 8 The image shows an optical amplifier used to amplify the signal light in the first band and the signal light in the second band.

[0099] Optionally, in Figure 8 There can be one pump control module that controls the power of the pump light of the multiple optical amplification components, or the number of pump control modules can be the same as the number of optical amplification components, with different pump control modules controlling the power of the pump light of different optical amplification components.

[0100] Optionally, in Figure 8 In this system, each optical amplification module in each band can perform single-stage amplification or multi-stage amplification.

[0101] Figure 8 The gain compensation method flowchart for the optical amplifier shown is provided below. Figure 9 Steps 901 to 907. Assume that the wavelength of the input signal light whose power changes belongs to the target wavelength band, and the corresponding optical amplification module is the target optical amplification module.

[0102] Step 901: The pump control module determines the power change information of the signal light in the target band.

[0103] Step 902: The pump control module adjusts the power of the pump light of the target light amplification module and locks the gain.

[0104] In this embodiment, the pump control module acquires the second gain and adjusts the power of the pump light of the target optical amplification module so that the gain of the signal light in the target band is the second gain. In this way, the gain of the signal light in the target band is locked to the second gain, or, to put it another way, the gain of the target optical amplification module is locked to the second gain.

[0105] In step 903, the pump control module uses the power change information to adjust the power of the pump light of the target light amplification module.

[0106] In this embodiment, the pump control module uses the power change information to determine the gain compensation amount for the signal light in the target band. Then, using this gain compensation amount, it adjusts the power of the pump light in the target optical amplification module.

[0107] The method for determining the gain compensation amount here is the same as the principle for determining the gain compensation amount mentioned earlier. The difference is that here the gain compensation amount is determined for the target band, while in the previous text the gain compensation amount was determined for the entire input signal light.

[0108] In step 904, the pump control module sends a control signal to the target optical amplification module, indicating the power of the pump light after power adjustment. The target optical amplification module uses the power-adjusted pump light to amplify the signal light in the target wavelength band.

[0109] In this embodiment, the pump control module sends a control signal to the target optical amplification module. This control signal can be either current or voltage. After receiving the control signal, the target optical amplification module determines the power of the pump light after power adjustment, outputs pump light of that power, and amplifies the signal light in the target band to perform gain compensation.

[0110] Step 905: The pump control module determines whether the gain of the signal light in the target band has reached the specified gain, which is the second gain plus the gain compensation amount.

[0111] In this embodiment, the power of the signal light output by the target optical amplification module is the first power, and the power of the input signal light is the first power. The units of the first power and the second power are dBm. The pump control module determines the difference between the first power and the second power, which is the gain of the signal light in the target band. The pump control module then determines whether this gain reaches the specified gain.

[0112] Step 906: If the specified gain is not achieved, the pump control module continues to fine-tune the power of the pump light of the target light amplification module.

[0113] In this embodiment, if the gain does not reach the specified gain, the pump control module continues to fine-tune the power of the pump light of the target optical amplification module until the gain of the signal light in the target band reaches the specified gain.

[0114] Step 907: If the specified gain is reached, the pump control module ends the adjustment of the pump light power and inputs the currently used control signal to the target light amplification module.

[0115] exist Figure 8 In the optical amplifier shown, if the power variation of the signal light in a certain band is small, the power of the pump light of the optical amplifier module corresponding to that band can be left unchanged, or finely adjusted based on the output power and input power of that band.

[0116] This explanation uses the target band as an example; the gain compensation principle for other bands is the same and will not be repeated here.

[0117] 3. The optical amplifier is a partially integrated optical amplifier.

[0118] The optical amplifier includes a first optical amplification module and multiple second optical amplification modules. The first optical amplification module amplifies the input signal light as a whole. Among the multiple second optical amplification modules, different modules amplify the signal light in different wavelength bands. For example, if the input signal light includes C-band and L-band signal light, the first optical amplification module amplifies both C-band and L-band signal light, one second optical amplification module amplifies the C-band signal light, and another second optical amplification module amplifies the L-band signal light.

[0119] Figure 10 and Figure 11 Two schematic diagrams of optical amplifier structures are provided. Figure 10 It detects the power of the input signal light and the power of the output signal light. Figure 11 It detects the power of the signal light in each band of the input signal light. For example... Figure 10 As shown, the optical amplifier includes an input splitter module, an input detection module, a first optical amplification module, a wavelength division multiplexer (WDM), multiple second optical amplification modules, a wavelength division multiplexer (WDM), an output splitter module, an output detection module, and a pump control module. The input splitter module is connected to the input of the optical amplifier via optical fiber. The input splitter module is also connected to the first optical amplification module and the input detection module via optical fiber. The first optical amplification module is connected to the WDM via optical fiber. The WDM is connected to each of the second optical amplification modules via optical fiber. Each second optical amplification module is connected to the WDM via optical fiber. The WDM is connected to the output of the optical amplifier and the output splitter via optical fiber. Both the input and output splitter modules are electrically connected to the pump control module. The WDM splitter splits the input signal light into multiple wavelength bands, which are then input to the corresponding second optical amplification modules. Each second optical amplification module amplifies the received signal light and outputs the amplified signal to the WDM. The WDM combines the received signal light into a single beam for output. Figure 10 and Figure 11 In this system, the optical amplifier includes a first-band optical amplification module and a second-band optical amplification module. The optical amplification module can perform single-stage amplification or multi-stage amplification.

[0120] Figure 10 For the gain compensation process in the optical amplifier shown, please refer to [link / reference]. Figure 12 Steps 1201 to 1207.

[0121] Step 1201: The pump control module determines the power change information of the input signal light.

[0122] Step 1202: The pump control module adjusts the power of the first pump light of the first optical amplification module and the power of the second pump light of the second optical amplification module to lock the gain.

[0123] In this embodiment, the pump control module acquires the second gain, adjusts the power of the pump light of the first optical amplification module according to the preset gain allocation ratio, and adjusts the power of the second pump light of each second optical amplification module so that the gain of the input signal light is the second gain, thus locking the gain of the input signal light to the second gain.

[0124] Optionally, the gain allocation ratio is a proportion of the gain. When obtaining the total gain of the input signal light, after obtaining the gains corresponding to the first optical amplification module and each of the second optical amplification modules according to the gain allocation ratio, it is converted into the power of the pump light. Alternatively, the gain allocation ratio is a proportion of the pump light. After obtaining the total pump light, the power of the first pump light and the power of the second pump light are obtained according to the gain allocation ratio.

[0125] In the following text, whenever the gain distribution ratio is mentioned, it can be understood as the ratio of gain or the ratio of pump light.

[0126] In addition, the gain allocation ratio includes the gain sharing ratio of the first optical amplification module and each of the second optical amplification modules. This allows direct determination of the gain or pump light power allocated to the first optical amplification module and each of the second optical amplification modules. Alternatively, the gain allocation ratio includes the gain sharing ratio of the first optical amplification module and all the second optical amplification modules, as well as the gain sharing ratio of the second optical amplification modules themselves. In this case, the gain or pump light power allocated to the first optical amplification module is first determined, and the gain or pump light power allocated to all the second optical amplification modules is also determined. Then, using the gain sharing ratio of the second optical amplification modules, the gain or pump light power allocated to each individual second optical amplification module is determined.

[0127] Step 1203: The pump control module uses the power change information to adjust the power of the pump light of the first optical amplification module, and uses the same power change information to adjust the power of the pump light of the second optical amplification module.

[0128] In this embodiment, the pump control module uses power change information to determine the gain compensation amount and distributes the gain compensation amount to the first optical amplification module and each of the second optical amplification modules according to a preset gain allocation ratio. Then, the power of the pump light of the first optical amplification module is adjusted using the gain compensation amount distributed to the first optical amplification module. Similarly, the power of the pump light of each of the second optical amplification modules is adjusted using the gain compensation amount distributed to each of the second optical amplification modules.

[0129] Without gain locking, the pump control module uses power change information to determine the first gain of the input signal light, and distributes the first gain to the first and second optical amplification modules according to a preset gain allocation ratio. Then, using the gain allocated to the first optical amplification module, the power of the pump light in the first optical amplification module is adjusted. Similarly, using the gain allocated to each of the second optical amplification modules, the power of the pump light in that module is adjusted.

[0130] The gain allocation ratios in steps 1202 and 1203 can be the same or different. The determination method is as follows: calculate the optimal gain allocation ratio based on simulation, or preset an initial gain allocation ratio, adjust the power of the pump light according to the gain allocation ratio, and determine whether the adjusted power of the pump light meets the gain requirement of the input signal light. If it does not meet the requirement, continue to adjust the gain allocation ratio until the adjusted power of the pump light meets the gain requirement, and find the gain allocation ratio.

[0131] In step 1204, the pump control module sends a first control signal to the first optical amplification module and a second control signal to at least one second optical amplification module. The first and second control signals indicate the power of the pump light after power adjustment. The first optical amplification module uses the power-adjusted pump light to amplify the input signal light. The second optical amplification module uses the power-adjusted pump light to amplify the received signal light.

[0132] The first control signal and the second control signal can both be current or voltage.

[0133] In this embodiment, after receiving the first control signal, the first optical amplification module determines the power of the pump light after power adjustment, outputs the pump light of that power, and amplifies the input signal light to perform gain compensation on the input signal light.

[0134] After receiving the second control signal, the second optical amplification module determines the power of the pump light after power adjustment, outputs the pump light of that power, and amplifies the received signal light to perform gain compensation on the received signal light.

[0135] Step 1205: The pump control module determines whether the gain of the input signal light has reached the specified gain. The specified gain is either the first gain or the second gain plus the gain compensation amount.

[0136] Step 1206: If the specified gain is not reached, the pump control module continues to fine-tune the power of the first pump light and the power of the second pump light.

[0137] Step 1207: If the specified gain is reached, the pump control module ends the adjustment of the pump light power and inputs the currently used control signal to the first optical amplification module and the second optical amplification module.

[0138] For a description of steps 1205 to 1207, please refer to [link / reference]. Figure 7 The process shown will not be repeated here.

[0139] Figure 11 The structure of the optical amplifier shown is similar to Figure 10 The optical amplifiers shown have similar structures, the difference being: Figure 11 In this system, the input detection module detects the power of the signal light in each wavelength band, and the output detection module also detects the power of the signal light in each wavelength band. For example, both the input and output detection modules include a wavelength division unit and multiple detection units. The wavelength division unit is connected to each detection unit via optical fiber. Different detection units are used to detect signal light in different wavelength bands. The wavelength division unit separates the signal light according to wavelength bands and sends it to the corresponding detection unit. The detection unit detects the received signal light, obtains an electrical signal, and sends it to the pump control module. Thus, in... Figure 11 In this process, the power of the signal light in each band can be obtained.

[0140] Figure 11 and Figure 10 The difference lies in the gain compensation of the optical amplifiers:

[0141] exist Figure 12 In step 1202, during gain locking, the gain allocated to the first optical amplification module is first determined according to the total power of the input signal light and the gain allocation ratio, and the total gain allocated to multiple second optical amplification modules is also determined. Then, the power of the pump light of the second optical amplification module is adjusted using the power of the input signal light and the power of the output signal light in each band to perform gain locking. In steps 1203 to 1204, during gain compensation, the total gain compensation amount allocated to the first optical amplification module and multiple second optical amplification modules is first determined according to the total power of the input signal light and the gain allocation ratio. Then, the power of the pump light of the second optical amplification module is adjusted using the power change information of each band to perform gain compensation. In steps 1205 to 1207, when determining whether the specified gain has been reached, the judgment is made based on the gain of each band. If the gain of a certain band does not reach the specified gain, the power of the second pump light corresponding to that band is adjusted.

[0142] 4. The optical amplifier is an optical amplifier that includes DGFF.

[0143] The previous section focused on gain compensation for the input signal light or different wavelength bands. However, considering that the gain compensation amount may vary for different wavelength bands, adjusting only the pump light power may not be optimal for the signal light in each wavelength band. Therefore, we consider using DGFF to correct the gain of the signal light at each wavelength.

[0144] Figure 13 A schematic diagram of the optical amplifier structure is provided. For example... Figure 13 As shown, an optical amplifier is generally a multi-stage optical amplifier, with the DGFF located between the i-th and (i+1)-th amplification modules, where i is greater than or equal to 1. For example, an optical amplifier may include a first-stage optical amplification module and a second-stage optical amplification module, with the DGFF located between them. Both the first-stage and second-stage optical amplification modules amplify the input signal light as a whole. An optical amplifier may include multiple DGFFs. Figure 13 Only one DGFF is shown in the image.

[0145] Figure 14 A flowchart of gain compensation is provided, see steps 1401 to 1407.

[0146] Step 1401: The pump control module determines the power change information of the input signal light.

[0147] Step 1402: The pump control module adjusts the power of the pump light of each stage of the optical amplification module and locks the gain.

[0148] Step 1403: The pump control module uses the power change information to adjust the power of the pump light of each stage of the optical amplification module, and determines the gain correction amount of the signal light of each wavelength in the input signal light.

[0149] In this embodiment, the process of adjusting the pump light power of each stage of the optical amplification module is as follows:

[0150] The pump control module uses power change information to determine the gain compensation amount and distributes it to each stage of the optical amplifier module according to a preset gain allocation ratio. Then, it uses the gain compensation amount distributed to each stage of the optical amplifier module to adjust the power of the pump light in each stage of the optical amplifier module.

[0151] Alternatively, without gain locking, the pump control module uses power change information to determine the first gain of the input signal light, and distributes the first gain to each stage of the optical amplification module according to a preset gain allocation ratio. Then, it uses the gain distributed to each stage of the optical amplification module to adjust the power of the pump light of each stage of the optical amplification module.

[0152] The process of determining the gain correction amount is as follows:

[0153] In the optical amplifier, the input detection module detects the overall power of the input signal light, and the pump control module uses the power change information of the input signal light to determine the gain correction amount for each wavelength of the signal light. In one example, the pump control module uses the correspondence between the power change range and the gain correction amount of the signal light to determine the gain correction amount for each wavelength of the signal light. In this correspondence, the gain correction amount can be for each wavelength of the signal light, or it can be for each band of the signal light, with the same gain correction amount for each wavelength within the same band. In another example, the pump control module uses the correspondence between the power change and the gain correction amount to determine the overall gain correction amount, and then uses the allocation ratio for each band to obtain the gain correction amount for each band, which is also the gain correction amount for each wavelength of the signal light. Here, the process of determining the allocation ratio is as follows: with a fixed gain compensation amount, the optimal gain correction amount for each wavelength of the signal light is analyzed under various gain or loss scenarios, and then statistics are performed to obtain the optimal allocation ratio.

[0154] Alternatively, in the optical amplifier, the input detection module detects the power of the signal light in each band, and the pump control module can then acquire the power change information of the signal light in each band. The pump control module uses this power change information to determine the gain correction amount for each band. In one example, for each band, the pump control module obtains the correspondence between the power change range and the gain correction amount for that band. Within this correspondence, it determines the power change range to which the power change belongs, and then determines the gain correction amount corresponding to that power change range. This gain correction amount is the gain correction amount for each wavelength of the signal light in that band. In another example, through simulation analysis, a calculation formula for the gain correction amount is obtained. The power change amount of the signal light in each band, or the power before and after the power change, is input into this calculation formula to obtain the gain compensation amount for the signal light in each band.

[0155] In step 1404, the pump control module sends control signals to each stage of the optical amplification module. These control signals indicate the power of the pump light after power adjustment and also send the gain correction amount for each wavelength of the signal light to the DGFF. Each stage of the optical amplification module uses the power-adjusted pump light to amplify the input signal light. The DGFF performs gain correction processing on the amplified signal light at each wavelength.

[0156] In this embodiment, after receiving the control signal, each optical amplification module determines the power of the pump light after power adjustment, outputs pump light of that power, and amplifies the received input signal light to perform gain compensation. The DGFF independently adjusts the received signal light according to the band or wavelength, that is, it uses the received gain correction amount to increase the gain of the signal light of each wavelength by the corresponding gain correction amount, and then outputs the gain-corrected signal light.

[0157] Step 1405: The pump control module determines whether the gain of the input signal light has reached the specified gain. The specified gain is either the first gain or the second gain plus the gain compensation amount.

[0158] Step 1406: If the specified gain is not achieved, the pump control module continues to adjust the power of the pump light of each stage of the optical amplification module and the gain correction amount of the signal light of each wavelength.

[0159] Step 1407: If the specified gain is reached, the pump control module ends the adjustment of the pump light power and gain correction amount, and inputs the currently used control signal to the optical amplification module.

[0160] Figure 14 The diagram below illustrates gain compensation for the entire input signal light. DGFF can also be applied to... Figure 8 , Figure 10 and Figure 11 In the optical amplifier shown, gain correction is performed in different wavelength bands. For example, in... Figure 8 In the optical amplifier shown, the first-band optical amplification module includes multiple optical amplification units, with DGGF located between the first-stage optical amplification unit and the second-stage optical amplification unit.

[0161] It should be noted that the reason for placing the DGFF between the two optical amplification modules is that after the DGFF corrects the gain, even if the gain of some wavelengths decreases significantly, the gain can still be boosted by the subsequent amplification module, so that the gain is not too low.

[0162] In the preceding text, the gain compensation process is also known as the virtual compression process. Before gain compensation, the power of the signal light at different wavelengths may vary, and the gain of some signal light may be outside the target gain range. Therefore, the key is to compensate the signal light outside the target gain range to fall within it, but not to compensate the signal light within the target gain range to fall outside it. The endpoints of the target gain range are the upper and lower limits of gain compensation. Therefore, when performing gain compensation, efforts should be made to stabilize the gain of all wavelengths of signal light between the upper and lower limits of gain compensation. For example, ... Figure 15As shown, a graph is provided showing the relationship between the wavelength of the signal light and the gain compensation amount. When the gain compensation amount is 3dB, the signal light with wavelength λ1 is compensated from outside the poor performance gain range to the target gain range, while the signal light with wavelength λ2 also remains within the target gain range.

[0163] In the previous text, when performing gain compensation on signal light of multiple wavelengths in a unified manner, although a single gain compensation amount was used for gain compensation, there was gain competition, which meant that the gain obtained by signal light of different wavelengths might be different.

[0164] In this embodiment, the gain of the optical amplifier is compensated solely by detecting changes in the power of the input signal light, resulting in rapid gain compensation. Furthermore, since it is implemented in software, no new hardware is added; the existing software for adjusting the pump light power is upgraded, simplifying the implementation process.

[0165] The structure of the optical amplification module mentioned above is related to the structure of the optical amplifier. For example, the optical amplifier is an erbium-doped fiber amplifier, and the optical amplification module is an erbium-doped fiber amplification module.

[0166] Figure 16 This is a structural diagram of the gain compensation device provided in the embodiments of this application. Figure 16 The illustrated device can be implemented as part or all of a device through software, hardware, or a combination of both. This device is applied to an optical amplifier and is used to implement the method flow executed by the optical amplifier in the embodiments of this application. For example... Figure 16 As shown, the device includes:

[0167] The power adjustment unit 1610 is used to adjust the power of the pump light of the optical amplifier based on the power change information of the input signal light, wherein the power change information includes the amount of power change and / or the power before and after the power change;

[0168] The control unit 1620 is used to amplify the input signal light based on the power-adjusted pump light in order to perform gain compensation on the input signal light.

[0169] In one alternative embodiment, the power adjustment unit 1610 is used for:

[0170] Based on the power change information, determine the gain compensation amount for the input signal light; based on the gain compensation amount, adjust the power of the pump light of the optical amplifier; or...

[0171] Based on the power change information, a first gain of the input signal light is determined, and based on the first gain, the power of the pump light of the optical amplifier is adjusted, wherein the first gain is the gain obtained after gain compensation of the input signal light.

[0172] In one alternative approach, the gain compensation amount is a compensation amount based on a second gain;

[0173] The power adjustment unit 1610 is further configured to determine the target power of the pump light of the optical amplifier based on the second gain before amplifying the input signal light based on the pump light after power adjustment.

[0174] The control unit 1620 is further configured to amplify the input signal light using the pump light of the target power, so that the gain of the input signal light is the second gain;

[0175] The power adjustment unit 1610 is used to adjust the power of the pump light of the optical amplifier based on the target power.

[0176] In an alternative embodiment, the power adjustment unit 1610 is further configured to determine a compensation time point before amplifying the input signal light based on the power-adjusted pump light, wherein the compensation time point is the time point of delay target duration after power overshoot of the output signal light, and the output signal light is the output signal light of the optical amplifier.

[0177] In one alternative embodiment, the optical amplifier includes an optical amplification module;

[0178] The control unit 1620 is used to control the optical amplification module to amplify the input signal light based on the pump light with adjusted power, so as to perform gain compensation on the input signal light.

[0179] In one alternative embodiment, the optical amplifier includes a plurality of optical amplification modules, wherein different optical amplification modules are used to amplify signal light in different wavelength bands;

[0180] The power adjustment unit 1610 is used to adjust the power of the pump light of the target optical amplification module based on the power change information of the signal light in the target band, wherein the target band is the band to which the signal light whose power changes in the input signal light belongs, and the target optical amplification module is the optical amplification module corresponding to the target band.

[0181] The control unit 1620 is used to control the target light amplification module to amplify the signal light of the target band based on the pump light with adjusted power, so as to perform gain compensation on the signal light of the target band.

[0182] In one alternative embodiment, the optical amplifier includes a first optical amplification module and a plurality of second optical amplification modules, wherein different second optical amplification modules are used to amplify signal light in different wavelength bands;

[0183] The power adjustment unit 1610 is used for:

[0184] Based on the power change information, the power of the first pump light of the first optical amplification module is adjusted, and the power of the second pump light of at least one second optical amplification module is adjusted, wherein the signal light amplified by the at least one second optical amplification module has a power change;

[0185] The control unit 1620 is used for:

[0186] Based on the first pump light with adjusted power, the first optical amplification module is controlled to amplify the input signal light in order to perform gain compensation on the input signal light;

[0187] Based on the second pump light with adjusted power, the at least one second optical amplification module is controlled to amplify the received signal light in order to perform gain compensation on the received signal light.

[0188] In one alternative embodiment, the power adjustment unit 1610 is used for:

[0189] Based on the power variation information of the signal light in the target band of the input signal light, adjust the power of the second pump light of the second optical amplification module corresponding to the target band; or,

[0190] Based on the power change information of the input signal light and the gain allocation ratio of the plurality of second optical amplification modules, the power of the second pump light of the at least one second optical amplification module is adjusted.

[0191] In one alternative embodiment, the optical amplifier further includes a dynamic gain flattening filter;

[0192] The power adjustment unit 1610 is further configured to determine the gain correction amount of each wavelength of the signal light in the input signal light based on the power change information of the input signal light.

[0193] The control unit 1620 is further configured to control the dynamic gain flattening filter to use the gain correction amount to perform gain correction processing on the amplified signal light of each wavelength.

[0194] In an alternative embodiment, the power adjustment unit 1610 is further configured to determine, based on the power change information of the input signal light, that the power change of the input signal light exceeds a target threshold before adjusting the power of the pump light of the optical amplifier based on the power change information of the input signal light.

[0195] In one alternative approach, the optical amplifier is applied to the optical multiplexing section.

[0196] Figure 16 For a detailed explanation of the gain compensation process of the device shown, please refer to the descriptions in the previous embodiments; it will not be repeated here. Figure 16 The device shown can be the pump control module mentioned above.

[0197] In this embodiment, the pump control module 1610 can be a processor in the optical amplifier, which is connected to the memory via a bus. The memory may include volatile memory, such as random access memory (RAM).

[0198] The memory 106 stores executable program code, which the processor 104 executes to implement the aforementioned gain compensation method. That is, the memory 106 stores program instructions for performing the aforementioned gain compensation method.

[0199] This application also provides a computer program product including program instructions stored in a computer-readable storage medium. The processor of the optical amplifier reads the program instructions from the computer-readable storage medium and executes the program instructions, causing the optical amplifier to perform the gain compensation method flow described above.

[0200] Those skilled in the art will recognize that the method steps and units described in the embodiments disclosed in this application can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the steps and components of each embodiment have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0201] In the embodiments provided in this application, it should be understood that the disclosed system architecture, apparatus, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules or components may be combined or integrated into another system, or some features may be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or modules, or may be electrical, mechanical, or other forms of connection.

[0202] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical modules; that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected to achieve the purpose of the embodiments of this application, depending on actual needs.

[0203] Furthermore, the modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module. The integrated modules described above can be implemented in hardware or in software.

[0204] If the integrated module is implemented as a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), RAM, magnetic disks, or optical disks.

[0205] In this application, the terms "first" and "second," etc., are used to distinguish identical or similar items that have substantially the same function and purpose. It should be understood that there is no logical or temporal dependency between "first" and "second," nor does it limit the quantity or order of execution. It should also be understood that although the following description uses the terms "first" and "second," etc., to describe various elements, these elements should not be limited by the terms. These terms are merely used to distinguish one element from another. For example, without departing from the scope of various examples, a first optical amplification module can be referred to as a second optical amplification module, and similarly, a second optical amplification module can be referred to as a first optical amplification module. Both the first and second optical amplification modules can be optical amplification modules, and in some cases, they can be separate and different optical amplification modules.

[0206] The phrase "at least one" in the preceding text can be understood as one or more.

[0207] The phrase "A and / or B" in the preceding text can be understood to include three cases: A, B, and A and B.

[0208] The above description is merely an exemplary embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and such modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for gain compensation, characterized in that, The method is applied to an optical amplifier, and the method includes: Based on the power change information of the input signal light, the power of the pump light of the optical amplifier is adjusted, wherein the power change information includes the amount of power change and / or the power before and after the power change; The input signal light is amplified based on the pump light with adjusted power to perform gain compensation.

2. The method according to claim 1, characterized in that, Adjusting the power of the pump light of the optical amplifier based on the power change information of the input signal light includes: Based on the power change information, determine the gain compensation amount for the input signal light; based on the gain compensation amount, adjust the power of the pump light of the optical amplifier; or... Based on the power change information, a first gain of the input signal light is determined, and based on the first gain, the power of the pump light of the optical amplifier is adjusted, wherein the first gain is the gain obtained after gain compensation of the input signal light.

3. The method according to claim 2, characterized in that, The gain compensation amount is a compensation amount based on the second gain; Before amplifying the input signal light based on the power-adjusted pump light, the method further includes: Based on the second gain, the target power of the pump light of the optical amplifier is determined; The input signal light is amplified using pump light of the target power so that the gain of the input signal light is the second gain; Adjusting the power of the pump light of the optical amplifier includes: Based on the target power, the power of the pump light of the optical amplifier is adjusted.

4. The method according to any one of claims 1 to 3, characterized in that, Before amplifying the input signal light based on the power-adjusted pump light, the method further includes: Determine the arrival time point, wherein the compensation time point is the time point after the power overshoot of the output signal light is delayed by the target duration, and the output signal light is the output signal light of the optical amplifier.

5. The method according to any one of claims 1 to 4, characterized in that, The optical amplifier includes an optical amplification module; The amplification of the input signal light based on the power-adjusted pump light for gain compensation includes: Based on the pump light with adjusted power, the optical amplification module is controlled to amplify the input signal light in order to perform gain compensation on the input signal light.

6. The method according to any one of claims 1 to 4, characterized in that, The optical amplifier includes multiple optical amplification modules, and different optical amplification modules are used to amplify signal light in different wavelength bands. Adjusting the power of the pump light of the optical amplifier based on the power change information of the input signal light includes: Based on the power change information of the signal light in the target band, the power of the pump light of the target optical amplification module is adjusted. The target band is the band to which the signal light whose power changes in the input signal light belongs, and the target optical amplification module is the optical amplification module corresponding to the target band. The amplification of the input signal light based on the power-adjusted pump light for gain compensation includes: Based on the pump light with adjusted power, the target light amplification module is controlled to amplify the signal light in the target band in order to perform gain compensation on the signal light in the target band.

7. The method according to any one of claims 1 to 4, characterized in that, The optical amplifier includes a first optical amplification module and multiple second optical amplification modules, wherein different second optical amplification modules are used to amplify signal light in different wavelength bands; Adjusting the power of the pump light of the optical amplifier based on the power change information of the input signal light includes: Based on the power change information, the power of the first pump light of the first optical amplification module is adjusted, and the power of the second pump light of at least one second optical amplification module is adjusted, wherein the signal light amplified by the at least one second optical amplification module has a power change; The amplification of the input signal light based on the power-adjusted pump light for gain compensation includes: Based on the first pump light with adjusted power, the first optical amplification module is controlled to amplify the input signal light in order to perform gain compensation on the input signal light; Based on the second pump light with adjusted power, the at least one second optical amplification module is controlled to amplify the received signal light in order to perform gain compensation on the received signal light.

8. The method according to claim 7, characterized in that, Adjusting the power of the second pump light of at least one second optical amplification module includes: Based on the power variation information of the signal light in the target band of the input signal light, adjust the power of the second pump light of the second optical amplification module corresponding to the target band; or, Based on the power change information of the input signal light and the gain allocation ratio of the plurality of second optical amplification modules, the power of the second pump light of the at least one second optical amplification module is adjusted.

9. The method according to any one of claims 1 to 8, characterized in that, The optical amplifier also includes a dynamic gain flattening filter; The method further includes: Based on the power change information of the input signal light, the gain correction amount of the signal light at each wavelength in the input signal light is determined; The dynamic gain flattening filter is controlled to use the gain correction amount to perform gain correction processing on the amplified signal light of each wavelength.

10. The method according to any one of claims 1 to 9, characterized in that, Before adjusting the power of the pump light of the optical amplifier based on the power variation information of the input signal light, the method further includes: Based on the power change information of the input signal light, it is determined that the power change of the input signal light exceeds the target threshold.

11. The method according to any one of claims 1 to 10, characterized in that, The optical amplifier is applied to the optical multiplexing section.

12. A gain compensation device, characterized in that, The device is used in an optical amplifier, and the device includes: The power adjustment unit is used to adjust the power of the pump light of the optical amplifier based on the power change information of the input signal light, wherein the power change information includes the amount of power change and / or the power before and after the power change; The control unit is used to amplify the input signal light based on the power-adjusted pump light in order to perform gain compensation on the input signal light.

13. The apparatus according to claim 12, characterized in that, The power adjustment unit is used for: Based on the power change information, determine the gain compensation amount for the input signal light; based on the gain compensation amount, adjust the power of the pump light of the optical amplifier; or... Based on the power change information, a first gain of the input signal light is determined, and based on the first gain, the power of the pump light of the optical amplifier is adjusted, wherein the first gain is the gain obtained after gain compensation of the input signal light.

14. The apparatus according to claim 13, characterized in that, The gain compensation amount is a compensation amount based on the second gain; The power adjustment unit is further configured to determine the target power of the pump light of the optical amplifier based on the second gain before amplifying the input signal light based on the pump light after power adjustment. The control unit is further configured to amplify the input signal light using the pump light of the target power, so that the gain of the input signal light is the second gain; The power adjustment unit is used to adjust the power of the pump light of the optical amplifier based on the target power.

15. The apparatus according to any one of claims 12 to 14, characterized in that, The power adjustment unit is further configured to determine the arrival time point before amplifying the input signal light based on the power-adjusted pump light, wherein the compensation time point is the time point after the power overshoot of the output signal light and the delay target duration, and the output signal light is the output signal light of the optical amplifier.

16. The apparatus according to any one of claims 12 to 15, characterized in that, The optical amplifier includes an optical amplification module; The control unit is used to control the optical amplification module to amplify the input signal light based on the pump light with adjusted power, so as to perform gain compensation on the input signal light.

17. The apparatus according to any one of claims 12 to 16, characterized in that, The optical amplifier includes multiple optical amplification modules, and different optical amplification modules are used to amplify signal light in different wavelength bands. The power adjustment unit is used to adjust the power of the pump light of the target optical amplification module based on the power change information of the signal light in the target band, wherein the target band is the band to which the signal light whose power changes in the input signal light belongs, and the target optical amplification module is the optical amplification module corresponding to the target band. The control unit is used to control the target light amplification module to amplify the signal light in the target band based on the pump light with adjusted power, so as to perform gain compensation on the signal light in the target band.

18. The apparatus according to any one of claims 12 to 17, characterized in that, The optical amplifier includes a first optical amplification module and multiple second optical amplification modules, wherein different second optical amplification modules are used to amplify signal light in different wavelength bands; The power adjustment unit is used for: Based on the power change information, the power of the first pump light of the first optical amplification module is adjusted, and the power of the second pump light of at least one second optical amplification module is adjusted, wherein the signal light amplified by the at least one second optical amplification module has a power change; The control unit is used for: Based on the first pump light with adjusted power, the first optical amplification module is controlled to amplify the input signal light in order to perform gain compensation on the input signal light; Based on the second pump light with adjusted power, the at least one second optical amplification module is controlled to amplify the received signal light in order to perform gain compensation on the received signal light.

19. The apparatus according to claim 18, characterized in that, The power adjustment unit is used for: Based on the power variation information of the signal light in the target band of the input signal light, adjust the power of the second pump light of the second optical amplification module corresponding to the target band; or, Based on the power change information of the input signal light and the gain allocation ratio of the plurality of second optical amplification modules, the power of the second pump light of the at least one second optical amplification module is adjusted.

20. The apparatus according to any one of claims 12 to 19, characterized in that, The optical amplifier also includes a dynamic gain flattening filter; The power adjustment unit is further configured to determine the gain correction amount of each wavelength of the signal light in the input signal light based on the power change information of the input signal light. The control unit is also used to control the dynamic gain flattening filter to use the gain correction amount to perform gain correction processing on the amplified signal light of each wavelength.

21. The apparatus according to any one of claims 12 to 20, characterized in that, The power adjustment unit is further configured to, before adjusting the power of the pump light of the optical amplifier based on the power change information of the input signal light, determine that the power change of the input signal light exceeds a target threshold based on the power change information of the input signal light.

22. An optical amplifier, characterized in that, The optical amplifier includes a processor and a memory; The processor is configured to execute program instructions in the memory to perform the method as described in any one of claims 1 to 11.

23. A computer-readable storage medium, characterized in that, Includes program instructions, which, when executed by the optical amplifier, cause the optical amplifier to perform the method as described in any one of claims 1 to 11.

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