A control method and device for a low-noise multi-pumped EDFA

Abstract

The application provides a control method and device of a low-noise multi-pump EDFA, noise index and transient performance are judged by acquiring input optical power and output optical power in real time, when the noise index and / or transient performance has a problem, corresponding correction parameters are generated to fine-tune the current ratio and / or bias of each pump, and finally the bias and current ratio meeting the noise index requirement and the transient performance requirement are output in the multi-round iteration debugging, so that the noise index of the optical fiber amplifier is reduced, and the transient performance of the optical fiber amplifier is optimized.

Description

Technical Field

[0001] This invention relates to the field of optical communication technology, and in particular to a control method and apparatus for a low-noise multi-pump EDFA. Background Technology

[0002] Erbium-doped fiber amplifiers (EDFAs) have greatly accelerated the development of optical communication, offering advantages such as transparency to data format and rate, high gain and low noise, no need for electrically regenerating repeaters, and large gain bandwidth. The noise figure is a key indicator of an EDFA, characterizing the degree of signal-to-noise ratio degradation of the input optical signal caused by the EDFA. Especially in pre-amplifier and intermediate-stage EDFAs, the noise figure directly affects the bit error rate of small signals in the receiver. EDFAs are indispensable components in dense optical multiplexing systems. In dense optical multiplexing systems, with the increase in traffic volume, the number of channels requiring uplink and downlink optical paths, as well as their channel power, also increase rapidly. Changes in the number of channels lead to changes in the input optical power of the EDFA, resulting in transient effects. These transient effects of the EDFA have a significant impact on the stability of dense optical multiplexing systems.

[0003] To achieve higher output optical power, cascaded multi-pump optical path structures are often used in EDFA modules. The current ratio of the subsequent pump stage has a much greater impact on the EDFA output power than the preceding pump stage. Therefore, increasing the current ratio of the subsequent pump stage can significantly reduce the amplitude of overshoot and undershoot in transient effects. However, under the condition of constant gain, increasing the current ratio of the subsequent physical pump stage will decrease the current ratio of the preceding physical pump stage. Since the current ratio of the preceding pump stage has a significant impact on the EDFA noise figure, noise figure and transient performance often present a trade-off in multi-pump cascaded optical paths.

[0004] Therefore, overcoming the shortcomings of the existing technology is an urgent problem to be solved in this technical field. Summary of the Invention

[0005] The technical problem to be solved by this invention is how to simultaneously optimize the noise figure and transient performance in a multi-pump cascaded optical path.

[0006] Firstly, a control method for a low-noise multi-pump EDFA is provided, including:

[0007] Set the initial current ratio and initial bias of each pump in the fiber amplifier.

[0008] Set the highest and lowest target gain of the fiber amplifier, and input the initial current ratio and initial bias into the first iteration to optimize the pump bias and current ratio through at least one iteration calculation;

[0009] Each iteration includes: within the gain interval formed by the lowest target gain and the highest target gain, adjusting the bias of each pump until the noise figure requirement of the fiber amplifier is met, thus obtaining the optimized bias; within the gain interval formed by the lowest target gain and the highest target gain, adjusting the current ratio of each pump according to the current target gain, the current input optical power, and the current output optical power until the transient performance requirement of the fiber amplifier is met, thus obtaining the optimized current ratio; within the gain interval formed by the lowest target gain and the highest target gain, verifying whether the fiber amplifier meets the noise figure requirement;

[0010] When the fiber amplifier meets the noise figure requirement, the optimized bias and the optimized current ratio are configured as parameters.

[0011] When the fiber amplifier does not meet the noise figure requirement, the optimized bias and optimized current ratio are input into the next iteration.

[0012] Preferably, adjusting the bias of each pump within the gain range formed by the lowest target gain and the highest target gain until the noise figure requirement of the fiber amplifier is met, to obtain the optimized bias, specifically includes:

[0013] The minimum input power corresponding to the lowest target gain and the minimum input power corresponding to the highest target gain are respectively input to the fiber amplifier. Starting from the minimum input power, the input power is gradually increased until one of the pumps reaches the maximum current or the maximum input power corresponding to the current target gain. During the process of increasing the input power, it is determined in real time whether the fiber amplifier meets the noise figure requirement, so the bias of each pump is adjusted synchronously until the fiber amplifier meets the noise figure requirement.

[0014] Preferably, the step of determining in real time whether the fiber amplifier meets the noise figure requirement during the process of increasing the input power, and thus synchronously adjusting the bias of each pump, specifically includes:

[0015] When the noise figure of the fiber amplifier exceeds the noise figure requirement, increase the bias of the pre-stage pump or decrease the bias of the post-stage pump until the noise figure of the fiber amplifier is lower than the noise figure requirement. The adjusted bias is then used as the optimized bias.

[0016] When the noise figure margin of the fiber amplifier is greater than the first preset margin value, the bias of the pre-stage pump is reduced or the bias of the post-stage pump is increased until the noise figure margin of the fiber amplifier is less than or equal to the first preset margin value. The adjusted bias is then used as the optimized bias.

[0017] Preferably, within the gain range formed by the lowest target gain and the highest target gain, adjusting the current ratio of each pump according to the current target gain, the current input optical power, and the current output optical power until the transient performance requirements of the fiber amplifier are met, thus obtaining the optimized current ratio, specifically includes:

[0018] The minimum input power corresponding to the lowest target gain and the minimum input power corresponding to the highest target gain are respectively input to the fiber amplifier. Starting from the minimum input power, the input power is gradually increased until one of the pumps reaches the maximum current or reaches the maximum input power corresponding to the current target gain.

[0019] During the process of increasing the input power, the slope of the input optical power is obtained in real time based on the current input optical power. The slope of the input optical power is used to determine whether the fiber amplifier meets the transient performance requirements. At the same time, the corresponding PID parameters and / or the current ratio of each pump are adjusted in real time until the fiber amplifier meets the transient performance requirements.

[0020] Preferably, the step of determining whether the fiber amplifier meets the transient performance requirements based on the slope of the input optical power, and simultaneously adjusting the corresponding PID parameters and / or the current ratio of each pump in real time until the fiber amplifier meets the transient performance requirements, specifically includes:

[0021] When the slope of the input optical power is greater than or equal to the preset lower transient decision threshold and less than or equal to the preset upper transient decision threshold, the original PID parameters are adjusted until the fiber amplifier meets the transient performance requirements. If adjusting the original PID parameters cannot make the fiber amplifier meet the transient performance requirements, the current ratio of each pump is synchronously adjusted according to the current target gain, the current input optical power and the current output optical power until the fiber amplifier meets the transient performance requirements.

[0022] When the slope of the input optical power is greater than the preset upper transient decision threshold, the fiber amplifier triggers an upper transient event, which does not meet the transient performance requirements. The upper parameters are adjusted until the fiber amplifier meets the transient performance requirements. If adjusting the upper parameters cannot make the fiber amplifier meet the transient performance requirements, the current ratio of each pump is synchronously adjusted according to the current target gain, the current input optical power, and the current output optical power until the fiber amplifier meets the transient performance requirements.

[0023] When the slope of the input optical power is less than the preset next-wave transient decision threshold, the fiber amplifier triggers a next-wave transient event, which does not meet the transient performance requirements. The next-wave parameters are adjusted until the fiber amplifier meets the transient performance requirements. If adjusting the next-wave parameters cannot make the fiber amplifier meet the transient performance requirements, the current ratio of each pump is synchronously adjusted according to the current target gain, the current input optical power, and the current output optical power until the fiber amplifier meets the transient performance requirements.

[0024] Preferably, the step of obtaining the slope of the input optical power in real time based on the current input optical power during the process of increasing the input power specifically includes:

[0025] The slope of the optical power change is obtained based on the input optical power, using the following formula:

[0026]

[0027] Where k is the slope of the change in optical power, X i Y is the i-th index of the input optical power value. i Let be the calibration value of the i-th input optical power, and n be the number of samples.

[0028] Preferably, the step of synchronously adjusting the current ratio of each pump according to the current target gain, current input optical power, and current output optical power until the fiber amplifier meets the transient performance requirements specifically includes:

[0029] The feedforward component is obtained in real time based on the current input optical power and the current target gain;

[0030] Within a preset window period, delay control is performed on the current input optical power and the current output optical power to obtain delay overshoot parameters, and PID parameters are obtained in real time based on the current input optical power and the output optical power. Feedback components are obtained based on the delay overshoot parameters and the PID parameters.

[0031] The feedforward component and the feedback component are summed to obtain the output optical power of the logical fiber amplifier. The current ratio of each pump is allocated and adjusted according to the output optical power of the logical fiber amplifier, and it is determined whether the fiber amplifier after allocation and adjustment meets the transient performance requirements.

[0032] When the adjusted fiber amplifier meets the transient performance requirements, the adjusted current ratio of each pump is taken as the optimized current ratio.

[0033] If the adjusted fiber amplifier does not meet the transient performance requirements, the current ratio of each pump is optimized and adjusted again until the fiber amplifier meets the transient performance requirements.

[0034] Preferably, if the adjusted fiber amplifier does not meet the transient performance requirements, the current ratio of each pump is further optimized and adjusted until the fiber amplifier meets the transient performance requirements, specifically including:

[0035] When the transient performance index of the fiber amplifier exceeds the transient performance requirement, reduce the current ratio of the pre-stage pump in all pumps, or increase the current ratio of the post-stage pump in all pumps, until the transient performance index is lower than the transient performance requirement. The current ratio adjusted in the second optimization is then used as the optimized current ratio.

[0036] When the transient performance index margin of the fiber amplifier is greater than the second preset margin value, the current ratio of the pre-stage pump in all pumps is increased, or the current ratio of the post-stage pump in all pumps is decreased, until the transient performance index margin is less than or equal to the second preset margin value. The current ratio adjusted in the second optimization is then used as the optimized current ratio.

[0037] Secondly, a control device for a low-noise multi-pump EDFA, used to apply the control method of the aforementioned low-noise multi-pump EDFA, includes: a pump allocation module, a logic pump module, a feedforward control module, a feedback and decision module, an input detection module, and an output detection module, wherein:

[0038] Multiple EDFAs are connected in sequence. The input terminal of the first EDFA is connected to the input detection module, and the output terminal of the last EDFA is connected to the output detection module. The input detection module is used to obtain the current input optical power, and the output detection module is used to obtain the current output optical power.

[0039] The pump allocation module is connected to multiple pumps respectively, and each pump is connected to a corresponding EDFA. The pump allocation module, logic pump module and feedback and decision module are connected in sequence. The feedback and decision module is connected to the input detection module and the output detection module respectively. The input detection module, feedforward control module and logic pump module are connected in sequence.

[0040] In each iteration: the feedforward control module obtains a feedforward component based on the current input optical power and the current target gain, and sends the feedforward component to the logic pump module; the feedback and judgment module determines whether the transient performance requirements of the fiber amplifier are met based on the current input optical power and the current output optical power, obtains a corresponding feedback component, and sends the feedback component to the logic pump module; the logic pump module adds the feedforward component and the feedback component to obtain a digitally controlled conversion signal for the pump output, constrains the pump output within the range of the maximum and minimum total current values ​​of all pumps, and sends the constrained digitally controlled conversion signal for the pump output to the pump allocation module; the pump allocation module performs corresponding current allocation for each pump based on the received digitally controlled conversion signal, the current ratio and bias of each pump, and the maximum and minimum current values ​​of each pump.

[0041] Preferably, the feedback and decision module includes a feedback control module and a transient decision module, wherein:

[0042] The transient decision module, the feedback control module, and the logic pump module are connected in sequence. The transient decision module is connected to the input detection module and the output detection module respectively. The feedback control module is connected to the input detection module and the output detection module respectively.

[0043] The transient decision module is used to obtain the slope of the input optical power based on the current input optical power, and to determine whether the transient performance requirements of the fiber amplifier are met based on the slope of the input optical power. Within a preset window period, the module performs delay control on the current input optical power and the current output optical power to obtain delay overshoot parameters. The module also obtains PID parameters in real time based on the current input optical power and the output optical power, and sends the delay overshoot parameters and the PID parameters to the feedback control module.

[0044] The feedback control module is used to perform closed-loop locking of the current target gain based on the current input optical power and the current output optical power, obtain the feedback component based on the delay overshoot parameter and the PID parameter, and separate and send the feedback to the logic pump module.

[0045] This invention provides a control method and apparatus for a low-noise multi-pump EDFA. By acquiring the input optical power and output optical power in real time, the noise figure and transient performance are monitored. When problems are detected in the noise figure and / or transient performance, corresponding correction parameters are generated to fine-tune the current ratio and / or bias of each pump. Through multiple rounds of iterative debugging, the final output bias and current ratio can meet both the noise figure and transient performance requirements, thereby achieving optimization of the transient performance of the fiber amplifier while reducing its noise figure. Attached Figure Description

[0046] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments of the present invention will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0047] Figure 1 This is a flowchart of a low-noise multi-pump EDFA control method provided in an embodiment of the present invention;

[0048] Figure 2 This is a flowchart of a transient performance judgment method in a low-noise multi-pump EDFA control method provided in an embodiment of the present invention;

[0049] Figure 3 This is a flowchart of a method for optimizing and adjusting the pump in a low-noise multi-pump EDFA control method provided in an embodiment of the present invention;

[0050] Figure 4 This is a schematic block diagram of a control device for a low-noise multi-pump EDFA provided in an embodiment of the present invention;

[0051] Figure 5 This is a schematic block diagram of another low-noise multi-pump EDFA control device provided in an embodiment of the present invention. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0053] In the description of this invention, the terms "inner", "outer", "longitudinal", "lateral", "upper", "lower", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and do not require that this invention must be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0054] In this invention, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0055] In this invention, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a direct connection or an indirect connection through an intermediate medium. Furthermore, the term "coupled" can refer to an electrical connection method for achieving signal transmission.

[0056] Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0057] Example 1:

[0058] This invention provides a low-noise multi-pump EDFA control method, such as... Figure 1 As shown, the method flow includes:

[0059] In step 101, the initial current ratio and initial bias of each pump in the fiber amplifier are set.

[0060] In this embodiment, the fiber amplifier is an erbium-doped fiber amplifier, which includes multiple pumps. According to the cascading order of the pumps, it includes a pre-stage pump and a post-stage pump. The current ratio of the post-stage pump has a much greater impact on the output power of the fiber amplifier than that of the pre-stage pump. Therefore, increasing the current ratio of the post-stage pump to the pre-stage pump can significantly reduce the amplitude of overshoot and undershoot in transient effects. Under the condition of constant gain, increasing the current ratio of the post-stage pump to the pre-stage pump will decrease the current ratio of the pre-stage pump to the post-stage pump. The current ratio of the pre-stage pump to the post-stage pump has a significant impact on the noise figure of the fiber amplifier. Therefore, noise figure and transient performance often have a mutually restrictive problem in multi-pump cascaded optical paths.

[0061] Adjusting the current ratio of each pump can affect the transient performance of the fiber amplifier, and adjusting the bias of each pump can affect the noise figure of the fiber amplifier. Before starting iterative tuning, the initial current ratio and initial bias of each pump are set. In order to ensure that the initial input current ratio and bias from the beginning of the iteration are as good as possible and to reduce the number of subsequent iterations, it is necessary to ensure that the noise figure corresponding to the initial current ratio and initial bias is as small as possible, and to improve the transient performance as much as possible while maintaining a low noise figure.

[0062] In this embodiment, according to the cascading sequence of each pump, the initial current ratio of the second pump and subsequent pumps is generally required to be no higher than 85% and no lower than 75%. Therefore, the initial current ratio of the first pump in the cascading pumps can be set to 100%, and the initial current value of the second and subsequent pumps can be set to 75% to 85%. The initial bias can be set to 0.

[0063] In step 102, the highest and lowest target gains of the fiber amplifier are set, and the initial current ratio and initial bias are input into the first iteration to optimize the pump bias and current ratio through at least one iteration calculation.

[0064] In this embodiment, the target gain can be the amplification factor of the fiber optic amplifier. As the target gain gradually increases, the corresponding input optical power to the fiber optic amplifier needs to increase synchronously.

[0065] In step 103, each iteration includes: within the gain range of the lowest target gain and the highest target gain, adjusting the bias of each pump until the noise figure requirement of the fiber amplifier is met, and obtaining the optimized bias; within the gain range of the lowest target gain and the highest target gain, adjusting the current ratio of each pump according to the current target gain, the current input optical power, and the current output optical power until the transient performance requirement of the fiber amplifier is met, and obtaining the optimized current ratio.

[0066] In step 104, within the gain range of the lowest target gain and the highest target gain, it is verified whether the fiber amplifier meets the noise figure requirement. If yes, proceed to step 105; otherwise, proceed to step 106.

[0067] The minimum input power corresponding to the lowest target gain and the minimum input power corresponding to the highest target gain are respectively input to the fiber amplifier. Starting from the minimum input power, the input power is gradually increased until one of the pumps reaches its maximum current or reaches the maximum input power corresponding to the current target gain. During the process of increasing the input power, it is continuously determined whether the noise figure requirement of the fiber amplifier is met. If the noise figure requirement of the fiber amplifier is not met, the bias of each pump is continuously adjusted within a preset window period based on the initial bias to ensure that the noise figure requirement of the fiber amplifier is continuously met. The noise figure requirement of the fiber amplifier can be: the noise figure is lower than a preset noise figure value, and the noise figure margin is less than or equal to a first preset margin. The preset window period, the preset noise figure value, and the first preset margin are all set by those skilled in the art according to the actual situation.

[0068] Based on the aforementioned bias adjustment, the minimum input power corresponding to the lowest target gain and the minimum input power corresponding to the highest target gain are re-inputted to the fiber amplifier. Starting from the minimum input power, the input power is gradually increased until one of the pumps reaches its maximum current or the maximum input power corresponding to the current target gain. During this increase in input power, the transient performance requirements of the fiber amplifier are continuously assessed based on the feedback output optical power. If the transient performance requirements are not met, the current ratio of each pump is continuously adjusted within a preset window period based on the initial current ratio and proportional-integral control to ensure that the transient performance requirements of the fiber amplifier are met. The transient performance requirements of the fiber amplifier can be: the transient performance index of the fiber amplifier is lower than a preset transient performance requirement, and the margin of the transient performance index of the fiber amplifier is less than or equal to a second preset margin value. The preset transient performance requirement and the second preset margin value are set by those skilled in the art.

[0069] In step 105, when the fiber amplifier meets the noise figure requirement, the optimized bias and the optimized current ratio are configured as parameters.

[0070] In step 106, when the fiber amplifier does not meet the noise figure requirement, the optimized bias and optimized current ratio are input into the next iteration.

[0071] Because adjusting the current ratio and bias of each pump in the single iteration mentioned above is difficult to meet the noise figure and transient performance requirements of the fiber amplifier in one go, and adjusting each pump cannot simultaneously take into account both noise figure and transient performance requirements, this embodiment monitors the noise figure and transient performance by acquiring the input optical power and output optical power in real time. When it is determined that there is a problem with the noise figure and / or transient performance, corresponding correction parameters are generated to fine-tune the current ratio and / or bias of each pump. In the multi-round iteration debugging, the final output bias and current ratio can meet both the noise figure and transient performance requirements, thereby achieving the optimization of the transient performance of the fiber amplifier while reducing the noise figure of the fiber amplifier.

[0072] During the process of increasing the input power, it is determined in real time whether the fiber amplifier meets the noise figure requirements, thereby synchronously adjusting the bias of each pump, specifically including:

[0073] When the noise figure of the fiber amplifier exceeds the noise figure requirement, increase the bias of the pre-stage pump or decrease the bias of the post-stage pump until the noise figure of the fiber amplifier is lower than the noise figure requirement. The adjusted bias is then used as the optimized bias.

[0074] When the noise figure margin of the fiber amplifier is greater than the first preset margin value, the bias of the pre-stage pump is reduced or the bias of the post-stage pump is increased until the noise figure margin of the fiber amplifier is less than or equal to the first preset margin value. The adjusted bias is then used as the optimized bias.

[0075] The input and output optical power values ​​of the fiber optic amplifier are acquired through corresponding modules. The transient performance of the fiber optic amplifier can be monitored using the input optical power value. When a transient effect is detected in the optical path, adjustments can be made based on the current input and output optical power. Adjustment parameters are obtained using proportional-integral control (PIC), and the current ratios of each pump are adjusted in real-time according to the transient performance status of the fiber optic amplifier. The design is as follows:

[0076] Within the gain range between the lowest and highest target gains, the current ratios of each pump are adjusted based on the current target gain, current input optical power, and current output optical power until the transient performance requirements of the fiber amplifier are met, resulting in optimized current ratios. Figure 2 As shown, the method flow includes:

[0077] In step 201, the minimum input power corresponding to the lowest target gain and the minimum input power corresponding to the highest target gain are respectively input to the fiber amplifier. Starting from the minimum input power, the input power is gradually increased until one of the pumps reaches the maximum current or reaches the maximum input power corresponding to the current target gain.

[0078] In step 202, during the process of increasing the input power, the slope of the input optical power is obtained in real time based on the current input optical power.

[0079] During the process of increasing the input power, the slope of the input optical power is obtained in real time based on the current input optical power. The slope of the input optical power is used to determine whether the fiber amplifier meets the transient performance requirements. At the same time, the corresponding PID parameters and / or the current ratio of each pump are adjusted in real time until the fiber amplifier meets the transient performance requirements.

[0080] In this embodiment, the acquired input optical power is shifted to obtain N levels, thereby ensuring that the current input optical power meets the minimum number of levels required for the least squares method to estimate the slope. Based on the current input optical power obtained at N levels and the least squares calculation formula, the slope k of the optical power change is estimated, as follows:

[0081]

[0082] Where k is the slope of the change in optical power, X i Y is the i-th index of the input optical power value. i Let be the calibrated value of the i-th input optical power, and n be the number of samples. The multiple input optical power values ​​are acquired sequentially over time. The N-stage shift acquisition refers to shifting the input optical power through an N-stage shift register to meet the requirements of the least squares method.

[0083] In step 203, when the slope of the input optical power is greater than or equal to the preset lower transient decision threshold and less than or equal to the preset upper transient decision threshold, the original PID parameters are adjusted until the fiber amplifier meets the transient performance requirements. If adjusting the original PID parameters cannot make the fiber amplifier meet the transient performance requirements, the current ratio of each pump is synchronously adjusted according to the current target gain, the current input optical power and the current output optical power until the fiber amplifier meets the transient performance requirements.

[0084] In step 204, when the slope of the input optical power is greater than the preset up-wave transient decision threshold, the fiber amplifier triggers an up-wave transient event, which does not meet the transient performance requirements. The up-wave parameters are adjusted until the fiber amplifier meets the transient performance requirements. If adjusting the up-wave parameters cannot make the fiber amplifier meet the transient performance requirements, the current ratio of each pump is synchronously adjusted according to the current target gain, the current input optical power, and the current output optical power until the fiber amplifier meets the transient performance requirements.

[0085] In step 205, when the slope of the input optical power is less than the preset next-wave transient decision threshold, the fiber amplifier triggers a next-wave transient event, which does not meet the transient performance requirements. The next-wave parameters are adjusted until the fiber amplifier meets the transient performance requirements. If adjusting the next-wave parameters cannot make the fiber amplifier meet the transient performance requirements, the current ratio of each pump is synchronously adjusted according to the current target gain, the current input optical power, and the current output optical power until the fiber amplifier meets the transient performance requirements.

[0086] The current ratio of each pump is synchronously adjusted according to the current target gain, current input optical power, and current output optical power until the fiber amplifier meets the transient performance requirements, such as... Figure 3 As shown, the method flow includes:

[0087] In step 301, the feedforward component is obtained in real time based on the current input optical power and the current target gain.

[0088] In this embodiment, when none of the physical pump currents have reached their maximum current, a target gain i is set. By iterating through the logic pump values ​​(pump_logic_dac) corresponding to different input optical powers (inputPwr_mw), the slope K_i and intercept B_i are obtained through linear fitting. Finally, according to the feedforward parameters of other target gains Gain_mw_1, Gain_mw_2, ..., Gain_mw_n calibrated in the previous step, K_1 and B_1, K_2 and B_2, etc. are obtained in sequence. Based on the target gain corresponding to K_1, K_2, ..., K_n, the slope K_k and intercept K_b are obtained by linear fitting; based on the target gain corresponding to B_1, B_2, ..., B_n, the intercept B_k and intercept B_b are obtained by linear fitting, thereby initially calculating the expected current value of each pump, and then obtaining the feedforward component. Subsequently, feedback adjustment can be performed based on the predetermined current value. The feedforward component can ensure the fast response of the corresponding fiber amplifier, and the feedback component can ensure the accuracy of the corresponding fiber amplifier.

[0089] In step 302, the current input optical power and the current output optical power are delayed within a preset window period to obtain a delay overshoot parameter, and PID parameters are obtained in real time based on the current input optical power and the output optical power. Feedback components are obtained based on the delay overshoot parameter and the PID parameter.

[0090] In this embodiment, the amplitude of transient overshoot and undershoot is suppressed by delaying the current input optical power and the current output optical power within a preset window period, and obtaining PID parameters in real time based on the current input optical power and the output optical power. Subsequently, the current ratio of each pump is allocated according to the delay overshoot parameter and the PID parameter.

[0091] In step 303, the feedforward component and the feedback component are summed to obtain the output optical power of the logical fiber amplifier. The current ratio of each pump is allocated and adjusted according to the output optical power of the logical fiber amplifier, and it is determined that the fiber amplifier after allocation and adjustment meets the transient performance requirements.

[0092] In this embodiment, the output optical power of the fiber amplifier is a reference value x, the current ratio of each pump is k, and the bias of each pump is b. Therefore, the corresponding power allocation of each pump is kx+b.

[0093] In step 304, when the adjusted fiber amplifier meets the transient performance requirements, the adjusted current ratio of each pump is taken as the optimized current ratio.

[0094] In step 305, if the adjusted fiber amplifier does not meet the transient performance requirements, the current ratio of each pump is optimized and adjusted again until the fiber amplifier meets the transient performance requirements.

[0095] The secondary optimization adjustment refers to performing optimization adjustment again based on the previous optimization adjustment.

[0096] If the adjusted fiber amplifier does not meet the transient performance requirements, then the current ratio of each pump is further optimized and adjusted until the fiber amplifier meets the transient performance requirements, specifically including:

[0097] When the transient performance index of the fiber amplifier exceeds the transient performance requirement, reduce the current ratio of the pre-stage pump in all pumps, or increase the current ratio of the post-stage pump in all pumps, until the transient performance index is lower than the transient performance requirement. The current ratio adjusted in the second optimization is then used as the optimized current ratio.

[0098] When the transient performance index margin of the fiber amplifier is greater than the second preset margin value, the current ratio of the pre-stage pump in all pumps is increased, or the current ratio of the post-stage pump in all pumps is decreased, until the transient performance index margin is less than or equal to the second preset margin value. The current ratio adjusted in the second optimization is then used as the optimized current ratio.

[0099] Example 2:

[0100] Embodiment 2 of the present invention provides a control device for a low-noise multi-pump EDFA based on Embodiment 1, for use with the control device for the low-noise multi-pump EDFA in Embodiment 1, such as... Figure 4 The module includes: a pump allocation module, a logic pump module, a feedforward control module, a feedback and decision module, an input detection module, and an output detection module, wherein:

[0101] Multiple EDFAs are connected in sequence. The input terminal of the first EDFA is connected to the input detection module, and the output terminal of the last EDFA is connected to the output detection module. The input detection module is used to obtain the current input optical power, and the output detection module is used to obtain the current output optical power.

[0102] like Figure 4 As shown, Figure 4 In the multi-pump cascaded optical path, there are n EDFAs, each EDFA is connected to a corresponding pump, and the number of pumps is also n, where n is a positive integer greater than 2.

[0103] In this embodiment, the input detection module is used to drive the corresponding input detection circuit and to obtain the calibration value of the input optical power input to the fiber amplifier. The calibration value of the input optical power is updated according to the subsequent first-in-last-out order. The module is also used to provide the data source to be processed for the subsequent feedforward control module and the feedback and judgment module. The feedforward control module and the feedback and judgment module adjust the current ratio of each pump according to the data source.

[0104] The output detection module is used to drive the corresponding output detection circuit and calibrate the corresponding output optical power. The output detection module is also used to obtain the calibration value of the output optical power and update the calibration value of the output optical power in the order of subsequent first-in-last-out. It is also used to provide the data source to be processed for the subsequent feedforward control module and feedback and judgment module. The feedforward control module and feedback and judgment module adjust the current ratio of each pump according to the data source.

[0105] The pump allocation module is connected to multiple pumps respectively, and each pump is connected to a corresponding EDFA. The pump allocation module, logic pump module and feedback and decision module are connected in sequence. The feedback and decision module is connected to the input detection module and the output detection module respectively. The input detection module, feedforward control module and logic pump module are connected in sequence.

[0106] In each iteration: the feedforward control module obtains a feedforward component based on the current input optical power and the current target gain, and sends the feedforward component to the logic pump module; the feedback and judgment module determines whether the transient performance requirements of the fiber amplifier are met based on the current input optical power and the current output optical power, obtains a corresponding feedback component, and sends the feedback component to the logic pump module; the logic pump module adds the feedforward component and the feedback component to obtain a digitally controlled conversion signal for the pump output, constrains the pump output within the range of the maximum and minimum total current values ​​of all pumps, and sends the constrained digitally controlled conversion signal for the pump output to the pump allocation module; the pump allocation module performs corresponding current allocation for each pump based on the digitally controlled conversion signal, the current ratio and bias of each pump, and the maximum and minimum current values ​​of each pump.

[0107] The feedforward control module is used to obtain the current input optical power from the input detection module, calculate the feedforward component based on the current input optical power and the target gain, and obtain the expected current value of each current through the feedforward component to improve the response speed of the fiber amplifier. The feedback and judgment module is used to process the input optical power calibration value, estimate the slope of the input optical power according to the least squares method, and determine whether there is a transient effect in the optical path based on the slope of the input optical power. When a transient effect is determined to exist, the input optical power calibration value and the output optical power calibration value are delayed within a preset window period to obtain the delay overshoot parameter, and the PID parameter is obtained in real time based on the current input optical power and the output optical power. The delay overshoot parameter and the PID parameter are used as feedback components.

[0108] The logic pump module adds the feedforward and feedback components to obtain the numerically controlled conversion signal of the pump output. It needs to constrain and adjust the pump output based on the maximum and minimum total current values ​​of all pumps to prevent the pump output from exceeding the maximum total current value or falling below the minimum total current value. When it exceeds the maximum total current value, the pump output constraint is adjusted to the maximum total current value of all pumps. When it falls below the minimum total current value, the pump output constraint is adjusted to the minimum total current value of all pumps. Then, the numerically controlled conversion signal of the adjusted pump output is sent to the pump distribution module.

[0109] The pump allocation module multiplies the received pump output signal x by a pre-set current ratio k for each pump, and adds a pre-set bias b for each pump to obtain the current value kx+b to be allocated to each pump. Then, it constrains the current value kx+b of each pump to the range between the maximum and minimum current values ​​corresponding to each pump. This prevents the allocated current from exceeding the maximum value, which could burn out the pump, or prevents the allocated current from falling below the minimum value, thereby ensuring that the pump operates in the linear region above the threshold current, rather than in the light-free cutoff region.

[0110] like Figure 5 As shown, the feedback and decision module includes a feedback control module and a transient decision module, wherein:

[0111] The transient decision module, the feedback control module, and the logic pump module are connected in sequence. The transient decision module is connected to the input detection module and the output detection module respectively, and the feedback control module is connected to the input detection module and the output detection module respectively.

[0112] The transient decision module is used to obtain the slope of the input optical power based on the current input optical power, and to determine whether the transient performance requirements of the fiber amplifier are met based on the slope of the input optical power. Within a preset window period, the module performs delay control on the current input optical power and the current output optical power to obtain delay overshoot parameters. The module also obtains PID parameters in real time based on the current input optical power and the output optical power, and sends the delay overshoot parameters and the PID parameters to the feedback control module.

[0113] The feedback control module is used to perform closed-loop locking of the current target gain based on the current input optical power and the current output optical power, obtain the feedback component based on the delay overshoot parameter and the PID parameter, and separate and send the feedback to the logic pump module.

[0114] Example 3:

[0115] Based on Embodiments 1 and 2, Embodiment 3 of the present invention provides an actual execution flow of a control method for a low-noise multi-pump EDFA, which is used to more intuitively demonstrate the corresponding control method.

[0116] Step 1, parameter initialization:

[0117] Set the initial current ratio for each pump, such as 100% for the first-stage pump and 85% for the second-stage pump, and set each initial bias to 0.

[0118] Set the baseline PID initialization parameters (pid_p, pid_i, pid_d), set the preset lower transient decision threshold and the preset upper transient decision threshold add_thr and drop_thr, as well as the corresponding initial preset window periods enter_window and exit_window, and set the initial delay overshoot parameters (add_dly, drop_dly) and the initial PID parameters (add_P_delta, add_I_delta, add_D_delta, drop_P_delta, drop_I_delta, drop_D_delta) to 0.

[0119] Step 2: Calibrate the pump's scaling factor and pre-bias.

[0120] Step 2-1: Set the highest and lowest target gains respectively, and within the corresponding input light range, gradually increase the input optical power starting from the minimum input optical power until one of the pumps reaches its maximum current. During the process of increasing the optical power, adjust the offset (offset_i) of each pump to ensure that the noise figure meets the noise figure requirements.

[0121] When the noise index exceeds the noise index requirement, the bias of the pump in the preceding stage of the cascade pump is increased, or the bias of the pump in the following stage is decreased; when the noise index margin is greater than the first preset margin value, the bias of the pump in the preceding stage is decreased, or the bias of the pump in the following stage is increased.

[0122] Step 2-2: Adjust the transient performance of the fiber amplifier at the highest and lowest target gain. This is done by adjusting the parameters in the feedforward control module and the transient decision module. Specifically, these parameters include the feedforward component, delay overshoot parameter, and PID parameter. If the adjusted parameters meet the transient performance requirements under each condition, the calibration is complete; otherwise, proceed to step 2-3.

[0123] Steps 2-3: Adjust the current ratio (ratio_i) of each pump to ensure the transient performance of the fiber amplifier meets the requirements. When the transient performance index exceeds the transient performance requirement, reduce the current ratio of the pump in the preceding stage of the cascaded pumps or increase the current ratio of the pump in the following stage. When the transient performance index margin is greater than the second preset margin value, increase the current ratio of the pump in the preceding stage or decrease the current ratio of the pump in the following stage.

[0124] Step 2-4: Verify whether the current ratio and bias of each pump can meet the noise figure requirements under the test conditions of Step 2-1. If they do, the calibration is complete; otherwise, start iterating from Step 2-1, fine-tuning the current ratio and bias of each pump.

[0125] Step 3, Amplify spontaneous emission (ASE) power calibration.

[0126] Amplified spontaneous emission power calibration is a necessary step for fiber amplifiers to lock the target gain. This step allows us to obtain the noise and signal components in the output power, thereby ensuring that the power of the signal component meets the requirements.

[0127] Because the self-excited radiation generated by the fiber amplifier overlaps with the signal band, the photodetector cannot distinguish between the signal power and the ASE power. Therefore, it is necessary to use an optical spectrum analyzer (OSA) to calibrate the ASE power in the output light to ensure that the signal power in the output light has an appropriate gain.

[0128] Step 3-1: Set the working mode to AGC. For variable gain fiber amplifiers that include a variable optical attenuator (VOA), the VOA needs to be set to attenuation mode.

[0129] Step 3-2: Take the minimum input optical power corresponding to the three gain points respectively. By adjusting the ASE calibration parameters ase_k or ase_b, make the gain reported by the spectrometer equal to the set gain. Record the current ase_mw according to the following formula:

[0130] ase_mw=ase_k*dB2mw(gain_set)+ase_b;

[0131] dB2mw(gain_set)=10^(gain_set / 10);

[0132] Step 3-3: Based on the three sets of ase_mw and dB2mw(gain_set) data obtained in Step 3-2, use linear fitting to obtain the ASE calibration parameters ase_k and ase_b.

[0133] Step 3-4: Verify the calibration accuracy of the ASE. By iterating through the light power at different gains, check whether the deviation between the gain reported by the spectrometer and the set gain is less than the requirement. If yes, the calibration is complete and meets the requirements. If not, the test conditions are not met, and the ASE calibration parameters are refitted starting from step 3-1.

[0134] Step 4: Feedforward calibration of the logic pump module.

[0135] The feedforward component of the logic pump module can quickly output the pump current ratio corresponding to the current gain based on the input optical power detection value at the current gain, thereby achieving the purpose of rapid pump adjustment. It mainly plays a role in scenarios such as transient control of input optical power or gain switching.

[0136] Step 4-1: Set the operating mode to AGC. For variable gain EDFAs that include VOA, the VOA needs to be set to attenuation mode.

[0137] Step 4-2: Set three target gains and take four input optical power values ​​for each gain. When the target gain is locked, if the current in each fiber amplifier reaches its maximum current, reduce the input optical power until all fiber amplifiers exit the maximum current state; otherwise, record the current logic pump (pump_logic_dac) and input optical power value dB2mw (input_pwr) according to the following formula:

[0138] pump_logic_dac=K*dB2mw(input_pwr)+B;

[0139] dB2mw(input_pwr)=10^(input_pwr / 10);

[0140] Based on the four sets of logic pump and input optical power values ​​for each gain, the current feedforward calibration parameters K_1 and B_1 are obtained by linear fitting. Similarly, the feedforward calibration parameters K_2, B_2 and K_3, B_3 for the other two gains are obtained.

[0141] Step 4-3: Based on the feedforward calibration parameters K_1, K_2, and K_3 obtained in Step 4-2 at the three gain points, perform linear fitting with the input optical power value to obtain the feedforward calibration parameters K_k and K_b; based on the feedforward calibration parameters B_1, B_2, and B_3 obtained in Step 4-2 at the three gain points, perform linear fitting with the input optical power value to obtain the feedforward calibration parameters B_k and B_b.

[0142] Step 4-4: Verify the calibration accuracy of the feedforward. With feedback enabled off, check whether the deviation between the optical power reported by the fiber amplifier and the set gain is less than the requirement by traversing the input optical power under different gain levels. If yes, the calibration is complete and meets the requirements. If not, the test conditions are not met, and the feedforward calibration parameters are refitted starting from step 4-1.

[0143] Step 5: Verify the noise figure and transient performance.

[0144] Since ASE power calibration will cause a corresponding increase in the current value of the logic pump module at the same gain, the noise figure will change slightly from that in step 2, thus requiring noise figure verification. If the verification fails, step 2 needs to be executed iteratively.

[0145] Since the feedforward calibration accuracy of the logic pump module directly affects transient performance, it is necessary to verify the transient performance. When the verification fails, the transient decision module's delay overshoot parameters and PID parameters are adjusted to optimize transient performance.

[0146] In summary, the low-noise multi-pump EDFA control method and apparatus provided in Embodiments 1, 2, and 3 can bring the following beneficial effects:

[0147] 1. This invention simplifies the closed-loop control of multiple cascaded pump lasers into a closed-loop lock of a single logic pump laser, greatly simplifying the feedforward calibration and ASE calibration of multiple pump lasers at different gains, and solving the problems of optical power oscillation and pump power consistency that may exist when controlling multiple pumps, thus facilitating the debugging and production of EDFA modules.

[0148] 2. This invention fully considers the differences between the factors affecting the noise figure and the transient effect, and directly controls the relative value of the logic pump when the input power is large and the initial proportional component of the pump when the input power is small by adjusting the scaling factor and pre-bias of each pump laser. This achieves the optimization of the noise figure of the EDFA module while ensuring transient performance, thereby further improving the signal-to-noise ratio of the optical network.

[0149] 3. This invention fully utilizes the advantages of FPGA's parallel computing, featuring rapid power detection and real-time parallel control. By adjusting the pump ratio and bias, combined with transient overshoot time, PID adjustment parameters, and input / output sampling delay in transient decision and control, it comprehensively optimizes the transient performance in the optical network and solves the problem of optical surge impact caused by EDFA transients.

[0150] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A control method for a low-noise multi-pump EDFA, characterized in that, include: Set the initial current ratio and initial bias of each pump in the fiber amplifier. Set the highest and lowest target gain of the fiber amplifier, and input the initial current ratio and initial bias into the first iteration to optimize the pump bias and current ratio through at least one iteration calculation; Each iteration includes: within the gain interval formed by the lowest target gain and the highest target gain, adjusting the bias of each pump until the noise figure requirement of the fiber amplifier is met, thus obtaining the optimized bias; within the gain interval formed by the lowest target gain and the highest target gain, adjusting the current ratio of each pump according to the current target gain, the current input optical power, and the current output optical power until the transient performance requirement of the fiber amplifier is met, thus obtaining the optimized current ratio; within the gain interval formed by the lowest target gain and the highest target gain, verifying whether the fiber amplifier meets the noise figure requirement; When the fiber amplifier meets the noise figure requirement, the optimized bias and the optimized current ratio are configured as parameters. When the fiber amplifier does not meet the noise figure requirement, the optimized bias and optimized current ratio are input into the next iteration.

2. The control method for low-noise multi-pump EDFA according to claim 1, characterized in that, Within the gain range defined by the lowest and highest target gains, the bias of each pump is adjusted until the noise figure requirement of the fiber amplifier is met, resulting in an optimized bias. Specifically, this includes: The minimum input power corresponding to the lowest target gain and the minimum input power corresponding to the highest target gain are respectively input to the fiber amplifier. Starting from the minimum input power, the input power is gradually increased until one of the pumps reaches the maximum current or the maximum input power corresponding to the current target gain. During the process of increasing the input power, it is determined in real time whether the fiber amplifier meets the noise figure requirement, so the bias of each pump is adjusted synchronously until the fiber amplifier meets the noise figure requirement.

3. The control method for a low-noise multi-pump EDFA according to claim 2, characterized in that, During the process of increasing the input power, it is determined in real time whether the fiber amplifier meets the noise figure requirements, thereby synchronously adjusting the bias of each pump. Specifically, this includes: When the noise figure of the fiber amplifier exceeds the noise figure requirement, increase the bias of the pre-stage pump or decrease the bias of the post-stage pump until the noise figure of the fiber amplifier is lower than the noise figure requirement. The adjusted bias is then used as the optimized bias. When the noise figure margin of the fiber amplifier is greater than the first preset margin value, the bias of the pre-stage pump is reduced or the bias of the post-stage pump is increased until the noise figure margin of the fiber amplifier is less than or equal to the first preset margin value. The adjusted bias is then used as the optimized bias.

4. The control method for a low-noise multi-pump EDFA according to claim 1, characterized in that, Within the gain range defined by the lowest and highest target gains, the current ratios of each pump are adjusted based on the current target gain, current input optical power, and current output optical power until the transient performance requirements of the fiber amplifier are met, resulting in an optimized current ratio. Specifically, this includes: The minimum input power corresponding to the lowest target gain and the minimum input power corresponding to the highest target gain are respectively input to the fiber amplifier. Starting from the minimum input power, the input power is gradually increased until one of the pumps reaches the maximum current or reaches the maximum input power corresponding to the current target gain. During the process of increasing the input power, the slope of the input optical power is obtained in real time based on the current input optical power. The slope of the input optical power is used to determine whether the fiber amplifier meets the transient performance requirements. At the same time, the corresponding PID parameters and / or the current ratio of each pump are adjusted in real time until the fiber amplifier meets the transient performance requirements.

5. The control method for a low-noise multi-pump EDFA according to claim 4, characterized in that, The step of determining whether the fiber amplifier meets the transient performance requirements based on the slope of the input optical power, and simultaneously adjusting the corresponding PID parameters and / or the current ratio of each pump in real time until the fiber amplifier meets the transient performance requirements, specifically includes: When the slope of the input optical power is greater than or equal to the preset lower transient decision threshold and less than or equal to the preset upper transient decision threshold, the original PID parameters are adjusted until the fiber amplifier meets the transient performance requirements. If adjusting the original PID parameters cannot make the fiber amplifier meet the transient performance requirements, the current ratio of each pump is synchronously adjusted according to the current target gain, the current input optical power and the current output optical power until the fiber amplifier meets the transient performance requirements. When the slope of the input optical power is greater than the preset upper transient decision threshold, the fiber amplifier triggers an upper transient event, which does not meet the transient performance requirements. The upper parameters are adjusted until the fiber amplifier meets the transient performance requirements. If adjusting the upper parameters cannot make the fiber amplifier meet the transient performance requirements, the current ratio of each pump is synchronously adjusted according to the current target gain, the current input optical power, and the current output optical power until the fiber amplifier meets the transient performance requirements. When the slope of the input optical power is less than the preset next-wave transient decision threshold, the fiber amplifier triggers a next-wave transient event, which does not meet the transient performance requirements. The next-wave parameters are adjusted until the fiber amplifier meets the transient performance requirements. If adjusting the next-wave parameters cannot make the fiber amplifier meet the transient performance requirements, the current ratio of each pump is synchronously adjusted according to the current target gain, the current input optical power, and the current output optical power until the fiber amplifier meets the transient performance requirements.

6. The control method for a low-noise multi-pump EDFA according to claim 4, characterized in that, The process of increasing input power, specifically obtaining the slope of the input optical power in real time based on the current input optical power, includes: The slope of the optical power change is obtained based on the input optical power, using the following formula: Where k is the slope of the change in optical power, X i Y is the i-th index of the input optical power value. i Let be the calibration value of the i-th input optical power, and n be the number of samples.

7. The control method for a low-noise multi-pump EDFA according to claim 5, characterized in that, The step of synchronously adjusting the current ratio of each pump according to the current target gain, current input optical power, and current output optical power until the fiber amplifier meets the transient performance requirements specifically includes: The feedforward component is obtained in real time based on the current input optical power and the current target gain; Within a preset window period, delay control is performed on the current input optical power and the current output optical power to obtain delay overshoot parameters, and PID parameters are obtained in real time based on the current input optical power and the output optical power. Feedback components are obtained based on the delay overshoot parameters and the PID parameters. The feedforward component and the feedback component are summed to obtain the output optical power of the logical fiber amplifier. The current ratio of each pump is allocated and adjusted according to the output optical power of the logical fiber amplifier, and it is determined whether the fiber amplifier after allocation and adjustment meets the transient performance requirements. When the adjusted fiber amplifier meets the transient performance requirements, the adjusted current ratio of each pump is taken as the optimized current ratio. If the adjusted fiber amplifier does not meet the transient performance requirements, the current ratio of each pump is optimized and adjusted again until the fiber amplifier meets the transient performance requirements.

8. The control method for a low-noise multi-pump EDFA according to claim 7, characterized in that, If the adjusted fiber amplifier does not meet the transient performance requirements, then the current ratio of each pump is further optimized and adjusted until the fiber amplifier meets the transient performance requirements, specifically including: When the transient performance index of the fiber amplifier exceeds the transient performance requirement, reduce the current ratio of the pre-stage pump in all pumps, or increase the current ratio of the post-stage pump in all pumps, until the transient performance index is lower than the transient performance requirement. The current ratio adjusted in the second optimization is then used as the optimized current ratio. When the transient performance index margin of the fiber amplifier is greater than the second preset margin value, the current ratio of the pre-stage pump in all pumps is increased, or the current ratio of the post-stage pump in all pumps is decreased, until the transient performance index margin is less than or equal to the second preset margin value. The current ratio adjusted in the second optimization is then used as the optimized current ratio.

9. A control device for a low-noise multi-pump EDFA, used for applying the control method of the low-noise multi-pump EDFA as described in any one of claims 1-8, characterized in that, include: The system comprises a pump allocation module, a logic pump module, a feedforward control module, a feedback and decision module, an input detection module, and an output detection module, wherein: Multiple EDFAs are connected in sequence. The input terminal of the first EDFA is connected to the input detection module, and the output terminal of the last EDFA is connected to the output detection module. The input detection module is used to obtain the current input optical power, and the output detection module is used to obtain the current output optical power. The pump allocation module is connected to multiple pumps respectively, and each pump is connected to a corresponding EDFA. The pump allocation module, logic pump module and feedback and decision module are connected in sequence. The feedback and decision module is connected to the input detection module and the output detection module respectively. The input detection module, feedforward control module and logic pump module are connected in sequence. In each iteration: the feedforward control module is used to obtain the feedforward component based on the current input optical power and the current target gain, and send the feedforward component to the logic pump module; The feedback and judgment module is used to determine whether the transient performance requirements of the fiber amplifier are met based on the current input optical power and the current output optical power, and obtain the corresponding feedback component, and send the feedback component to the logic pump module; the logic pump module is used to add the feedforward component and the feedback component to obtain the numerically controlled conversion signal of the pump output, and constrain the pump output within the range of the maximum and minimum total current values ​​of all pumps, and send the constrained numerically controlled conversion signal of the pump output to the pump allocation module; the pump allocation module is used to perform corresponding current allocation for each pump based on the received numerically controlled conversion signal, the current ratio and bias of each pump, and the maximum and minimum current values ​​of each pump.

10. The control device for a low-noise multi-pump EDFA according to claim 9, characterized in that, The feedback and decision module includes a feedback control module and a transient decision module, wherein: The transient decision module, the feedback control module, and the logic pump module are connected in sequence. The transient decision module is connected to the input detection module and the output detection module respectively. The feedback control module is connected to the input detection module and the output detection module respectively. The transient decision module is used to obtain the slope of the input optical power based on the current input optical power, and to determine whether the transient performance requirements of the fiber amplifier are met based on the slope of the input optical power. Within a preset window period, the module performs delay control on the current input optical power and the current output optical power to obtain delay overshoot parameters. The module also obtains PID parameters in real time based on the current input optical power and the output optical power, and sends the delay overshoot parameters and the PID parameters to the feedback control module. The feedback control module is used to perform closed-loop locking of the current target gain based on the current input optical power and the current output optical power, obtain the feedback component based on the delay overshoot parameter and the PID parameter, and separate and send the feedback to the logic pump module.

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