CN118017341A - Control method and device for low-noise multi-pump EDFA - Google Patents

Abstract

The invention provides a control method and a device for low-noise multi-pump EDFA, which are characterized in that input optical power and output optical power are obtained in real time, noise indexes and transient performances are judged, corresponding correction parameters are generated when the noise indexes and/or the transient performances are judged to be problematic, the current proportion and/or the bias quantity of each pump are finely adjusted, and in the process of multi-round iteration debugging, the bias quantity and the current proportion which can meet the noise index requirements and the transient performance requirements are finally output, so that the transient performances of an optical fiber amplifier are optimized on the basis of reducing the noise indexes of the optical fiber amplifier.

Description

Control method and device for low-noise multi-pump EDFA

Technical Field

The invention relates to the technical field of optical communication, in particular to a control method and a device of a low-noise multi-pump EDFA.

Background

The erbium-doped fiber amplifier (Erbium Doped Fiber Application, abbreviated as EDFA) greatly accelerates the development of optical communication, and has the advantages of transparency to data format and speed, large gain noise, no need of an electric regeneration repeater and large gain bandwidth, and the like. Noise figure is a key indicator of an EDFA, which characterizes the degree of degradation of the signal-to-noise ratio of the input optical signal caused by the EDFA, especially in a front-end EDFA and an intermediate-stage EDFA, where the noise figure directly affects the bit error rate of the small signal in the receiver. EDFAs are indispensable important devices in dense optical wave multiplexing systems. In the dense optical wave multiplexing system, as the traffic volume increases, the number of channels and the channel power of the upper and lower optical paths are also rapidly increased, and the change of the number of channels causes the change of the input optical power of the EDFA so as to generate transient effects, which have important influence on the stability of the dense optical wave multiplexing system.

In order to realize larger output optical power, a multi-pump cascade optical path structure is often adopted in the EDFA module, wherein the influence of the current proportion of the rear-stage pump on the output power of the EDFA is far greater than that of the front-stage pump, so that the over-undershoot amplitude in the transient effect can be obviously reduced by increasing the current proportion of the rear-stage pump. However, under the condition of unchanged gain, the current proportion of the post-stage physical pump is increased while the current proportion of the pre-stage physical pump is reduced, and the influence of the current proportion of the pre-stage pump on the EDFA noise index is remarkable, so that the noise index and the transient performance often have the problem of mutual restriction in a multi-pump cascade optical path.

In view of this, overcoming the drawbacks of the prior art is a problem to be solved in the art.

Disclosure of Invention

The invention aims to solve the technical problem of optimizing noise figure and transient performance simultaneously in a multi-pump cascade optical path.

In a first aspect, a control method of a low noise multi-pump EDFA is provided, including:

Setting initial current proportion and initial bias of each pump in the optical fiber amplifier;

Setting the highest target gain and the lowest target gain of the optical fiber amplifier, and inputting the initial current proportion and the initial bias quantity into a first round of iteration to optimize the bias quantity and the current proportion of the pump through at least one iteration calculation;

Each iteration includes: adjusting the offset of each pump in a gain interval formed by the lowest target gain and the highest target gain until the noise index requirement of the optical fiber amplifier is met, and obtaining an optimized offset; in a gain section formed by the lowest target gain and the highest target gain, adjusting the current proportion 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 optical fiber amplifier is met, and obtaining an optimized current proportion; checking whether the optical fiber amplifier meets the noise figure requirement in a gain interval formed by the lowest target gain and the highest target gain;

When the optical fiber amplifier meets the noise figure requirement, the optimized bias and the optimized current proportion are used as parameters for configuration;

and when the optical fiber amplifier does not meet the noise figure requirement, inputting the optimized bias quantity and the optimized current proportion into the next iteration.

Preferably, the adjusting the offset of each pump in the gain interval formed by the lowest target gain and the highest target gain until the noise figure requirement of the optical fiber amplifier is met, and obtaining the optimized offset specifically includes:

Respectively inputting the minimum input power corresponding to the minimum target gain and the minimum input power corresponding to the maximum target gain into the optical fiber amplifier, and gradually increasing the input power from the minimum input power until one pump reaches the maximum current or the maximum input power corresponding to the current target gain; in the process of increasing the input power, judging whether the optical fiber amplifier meets the noise index requirement in real time, so that the bias of each pump is synchronously adjusted until the optical fiber amplifier meets the noise index requirement.

Preferably, in the process of increasing the input power, whether the optical fiber amplifier meets the noise figure requirement is judged in real time, so that the bias of each pump is synchronously adjusted, and the method specifically comprises the following steps:

When the noise index of the optical fiber amplifier exceeds the noise index requirement, increasing the offset of the front-stage pump or reducing the offset of the rear-stage pump until the noise index of the optical fiber amplifier is lower than the noise index requirement, and taking the adjusted offset as the optimized offset;

And when the margin of the noise index of the optical fiber amplifier is larger than a first preset margin value, reducing the offset of the front-stage pump or increasing the offset of the rear-stage pump until the margin of the noise index of the optical fiber amplifier is smaller than or equal to the first preset margin value, and taking the adjusted offset as the optimized offset.

Preferably, in the gain section formed by the lowest target gain and the highest target gain, the current proportion of each pump is adjusted according to the current target gain, the current input optical power and the current output optical power until the transient performance requirement of the optical fiber amplifier is met, and the optimized current proportion is obtained, which specifically includes:

Respectively inputting the minimum input power corresponding to the minimum target gain and the minimum input power corresponding to the maximum target gain into the optical fiber amplifier, and gradually increasing the input power from the minimum input power until one pump reaches the maximum current or the maximum input power corresponding to the current target gain;

In the process of increasing the input power, the slope of the input optical power is obtained in real time according to the current input optical power, whether the current optical fiber amplifier meets the transient performance requirement is judged according to the slope of the input optical power, and the corresponding PID parameters and/or the current proportion of each pump are adjusted in real time until the optical fiber amplifier meets the transient performance requirement.

Preferably, the step of judging whether the current optical fiber amplifier meets the transient performance requirement according to the slope of the input optical power, and simultaneously adjusting the corresponding PID parameter and/or the current proportion of each pump in real time until the optical fiber amplifier meets the transient performance requirement specifically includes:

When the slope of the input optical power is larger than or equal to a preset downlink transient judgment threshold and smaller than or equal to a preset uplink transient judgment threshold, adjusting original PID parameters until the optical fiber amplifier meets transient performance requirements, and if the optical fiber amplifier cannot meet the transient performance requirements by adjusting the original PID parameters, synchronously adjusting the current proportion of each pump according to the current target gain, the current input optical power and the current output optical power until the optical fiber amplifier meets the transient performance requirements;

When the slope of the input optical power is larger than a preset uplink transient judgment threshold, triggering an uplink transient event by the optical fiber amplifier, and not meeting the transient performance requirement, adjusting the uplink parameter until the optical fiber amplifier meets the transient performance requirement, and if the optical fiber amplifier can not meet the transient performance requirement by adjusting the uplink parameter, synchronously adjusting the current proportion of each pump according to the current target gain, the current input optical power and the current output optical power until the optical fiber amplifier meets the transient performance requirement;

When the slope of the input optical power is smaller than a preset down-wave transient state judgment threshold, the optical fiber amplifier triggers a down-wave transient state event, the transient state performance requirement is not met, the down-wave parameters are adjusted until the optical fiber amplifier meets the transient state performance requirement, if the down-wave parameters cannot be adjusted to enable the optical fiber amplifier to meet the transient state performance requirement, the current proportion 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 optical fiber amplifier meets the transient state performance requirement.

Preferably, in the process of increasing the input power, obtaining the slope of the input optical power in real time according to the current input optical power specifically includes:

and obtaining the slope of the optical power change according to the input optical power, wherein the formula is as follows:

Where k is the slope of the optical power change, X _i is the i-th sequence number of the input optical power value, Y _i is the i-th input optical power scaling value, and n is the number of sample samples.

Preferably, the current proportion 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 optical fiber amplifier meets the transient performance requirement, which specifically comprises:

acquiring a feedforward component according to the current input optical power and the current target gain in real time;

Delay control is carried out on the current input optical power and the current output optical power in a preset window period to obtain delay overshoot parameters, PID parameters are obtained in real time according to the current input optical power and the output optical power, and feedback components are obtained according to the delay overshoot parameters and the PID parameters;

Summing the feedforward component and the feedback component, obtaining the output optical power of the optical fiber amplifier on logic, distributing and adjusting the current proportion of each pump according to the output optical power of the optical fiber amplifier on logic, and judging whether the distributed and adjusted optical fiber amplifier meets the transient performance requirement;

When the regulated optical fiber amplifier meets the transient performance requirement, the current proportion of each pump after regulation is used as the optimized current proportion;

and when the regulated optical fiber amplifier does not meet the transient performance requirement, carrying out secondary optimization regulation on the current proportion of each pump until the optical fiber amplifier meets the transient performance requirement.

Preferably, when the adjusted optical fiber amplifier does not meet the transient performance requirement, the current proportion of each pump is adjusted in a secondary optimization manner until the optical fiber amplifier meets the transient performance requirement, which specifically includes:

When the transient performance index of the optical fiber amplifier exceeds the transient performance requirement, reducing the current proportion of the front stage pumping in all pumping or increasing the current proportion of the rear stage pumping in all pumping until the transient performance index is lower than the transient performance requirement, and taking the current proportion regulated by secondary optimization as the optimized current proportion;

And when the margin of the transient performance index of the optical fiber amplifier is larger than a second preset margin value, increasing the current proportion of the front-stage pumping in all pumping or reducing the current proportion of the rear-stage pumping in all pumping until the margin of the transient performance index is smaller than or equal to the second preset margin value, and taking the current proportion regulated by secondary optimization as the optimized current proportion.

In a second aspect, a control device for a low noise multi-pump EDFA, configured to apply the control method for a low noise multi-pump EDFA, includes: the system comprises a pump distribution module, a logic pump module, a feedforward control module, a feedback and judgment module, an input detection module and an output detection module, wherein:

The multiple EDFAs are sequentially connected, the input end of the first EDFA is connected with the input detection module, and the output end of the last EDFA is connected with the output detection module; the input detection module is used for acquiring the current input optical power, and the output detection module is used for acquiring the current output optical power;

The pump distribution module is connected with a plurality of pumps respectively, each pump is connected with a corresponding EDFA, the pump distribution module, the logic pump module and the feedback and judgment module are sequentially connected, the feedback and judgment module is connected with the input detection module and the output detection module respectively, and the input detection module, the feedforward control module and the logic pump module are sequentially connected;

In each iteration: the feedforward control module is used for obtaining a feedforward component according to the current input optical power and the current target gain and sending the feedforward component to the logic pumping module; the feedback and judging module is used for judging whether the transient performance requirement of the optical fiber amplifier is met or not according to the current input optical power and the current output optical power, obtaining a corresponding feedback component and sending the feedback component to the logic pumping module; the logic pumping module is used for adding the feedforward component and the feedback component to obtain a numerical control conversion signal of the pumping output quantity, restraining the pumping output quantity within the interval of the maximum total current value and the minimum total current value of all pumps, and sending the numerical control conversion signal of the restrained pumping output quantity to the pumping distribution module; the pump distribution module is used for carrying out corresponding current distribution on each pump according to the received numerical control conversion signal, the current proportion and the bias quantity of each pump and the maximum current value and the minimum current value of each pump.

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

The transient state judgment module, the feedback control module and the logic pumping module are connected in sequence, the transient state judgment module is connected with the input detection module and the output detection module respectively, and the feedback control module is connected with the input detection module and the output detection module respectively;

The transient state judging module is used for obtaining the slope of the input optical power according to the current input optical power, judging whether the transient state performance requirement of the optical fiber amplifier is met according to the slope of the input optical power, carrying out delay control on the current input optical power and the current output optical power in a preset window period to obtain a delay overshoot parameter, obtaining a PID parameter in real time according to the current input optical power and the output optical power, and sending the delay overshoot parameter and the PID parameter to the feedback control module;

The feedback control module is used for performing closed-loop locking on the current target gain according to the current input optical power and the current output optical power, obtaining a feedback component according to the delay overshoot parameter and the PID parameter, and sending the feedback component to the logic pumping module in a separated mode.

The invention provides a control method and a device for low-noise multi-pump EDFA, which are used for monitoring noise figure and transient performance by acquiring input optical power and output optical power in real time, generating corresponding correction parameters when judging that the noise figure and/or the transient performance are in problem, finely adjusting the current proportion and/or the bias quantity of each pump, and finally outputting the bias quantity and the current proportion which can meet the noise figure requirement and the transient performance requirement in the multi-round iteration debugging, so that the transient performance of an optical fiber amplifier is optimized on the basis of reducing the noise figure of the optical fiber amplifier.

Drawings

In order to more clearly illustrate the technical solution of the embodiments of the present invention, the drawings that are required to be used in the embodiments of the present invention will be briefly described below. It is evident that the drawings described below are only some embodiments of the present invention and that other drawings may be obtained from these drawings without inventive effort for a person of ordinary skill in the art.

FIG. 1 is a method flow diagram of a control method for a low noise multi-pump EDFA according to an embodiment of the present invention;

FIG. 2 is a flow chart of a method for judging transient performance in a control method of a low-noise multi-pump EDFA according to an embodiment of the present invention;

FIG. 3 is a flow chart of a method for optimizing and adjusting pumps in a control method of a low noise multi-pump EDFA according to an embodiment of the present invention;

FIG. 4 is a schematic block diagram of a control device for a low noise multi-pump EDFA according to an embodiment of the present invention;

Fig. 5 is a schematic block diagram of another control device for a low noise multi-pump EDFA according to an embodiment of the invention.

Detailed Description

The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.

In the description of the present invention, the terms "inner", "outer", "longitudinal", "transverse", "upper", "lower", "top", "bottom", etc. refer to an orientation or positional relationship based on that shown in the drawings, merely for convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.

The terms "first," "second," and the like herein are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first", "a second", etc. may explicitly or implicitly include one or more such feature. In the description of the present invention, unless otherwise indicated, the meaning of "a plurality" is two or more.

In the present invention, unless explicitly specified and limited otherwise, the term "connected" is to be construed broadly, and for example, "connected" may be either fixedly connected, detachably connected, or integrally formed; can be directly connected or indirectly connected through an intermediate medium. Furthermore, the term "coupled" may be a means of electrical connection for achieving signal transmission.

In addition, the technical features of the embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.

Example 1:

the embodiment of the invention provides a control method of a low-noise multi-pump EDFA, as shown in fig. 1, the method flow comprises the following steps:

In step 101, an initial current ratio and an initial bias amount of each pump in the optical fiber amplifier are set.

In this embodiment, the optical fiber amplifier is an erbium-doped optical fiber amplifier, and includes a plurality of pumps, including a front-stage pump and a rear-stage pump according to a cascade sequence of each pump; the ratio of the current of the rear-stage pump is greatly greater than that of the front-stage pump, so that the ratio of the current of the rear-stage pump to the current of the front-stage pump can be increased to obviously reduce the over undershoot amplitude in the transient effect, the ratio of the current of the rear-stage pump to the current of the front-stage pump is increased under the condition of unchanged gain, the ratio of the current of the front-stage pump to the current of the rear-stage pump is reduced, and the ratio of the current of the front-stage pump to the current of the rear-stage pump has obvious influence on the noise index of the optical fiber amplifier, so that the noise index and the transient performance often have the problem of mutual restriction in a multi-pump cascade optical path.

The transient performance of the optical fiber amplifier can be influenced by adjusting the current ratio of each pump, and the noise figure of the optical fiber amplifier can be influenced by adjusting the offset of each pump. Before starting to enter iterative adjustment, the initial current proportion and the initial offset of each pump are set, so that the current proportion and the offset which are initially input to the iteration are guaranteed to be as excellent as possible, the subsequent iteration times are reduced, the noise indexes corresponding to the initial current proportion and the initial offset are guaranteed to be as small as possible, and the transient performance is improved as much as possible on the basis of guaranteeing the small noise indexes.

In this embodiment, according to the cascade sequence of each pump, the initial current ratio of the second pump and the subsequent pumps generally needs to be not higher than 85% and not lower than 75%, so that the initial current ratio of the first pump in the cascade pump can be set to 100%, and the initial current values of the second pump and the subsequent other pumps can be set to 75% -85%; the initial offset may be set to 0.

In step 102, the highest target gain and the lowest target gain of the optical fiber amplifier are set, and the initial current proportion and the initial bias amount are input into a first round of iteration, so that the bias amount and the current proportion of the pump are optimized through at least one iteration calculation.

In this embodiment, the target gain may be an amplification factor of the optical fiber amplifier, and when the target gain is gradually increased, the corresponding input optical power input to the optical fiber amplifier needs to be increased synchronously.

In step 103, each iteration includes: adjusting the bias quantity of each pump in the gain interval of the lowest target gain and the highest target gain until the noise index requirement of the optical fiber amplifier is met, and obtaining the optimized bias quantity; and in the gain interval of the lowest target gain and the highest target gain, adjusting the current proportion 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 optical fiber amplifier is met, and obtaining the optimized current proportion.

In step 104, in the gain interval of the lowest target gain and the highest target gain, checking whether the optical fiber amplifier meets the noise figure requirement, if yes, jumping to step 105, and if not, jumping to step 106.

Inputting the minimum input power corresponding to the minimum target gain and the minimum input power corresponding to the maximum target gain into the optical fiber amplifier respectively, starting to gradually increase the input power from the minimum input power until one pump reaches the maximum current or the maximum input power corresponding to the current target gain, continuously judging whether the noise index requirement of the optical fiber amplifier is met in the process of increasing the input power, and continuously adjusting the bias of each pump in a preset window period on the basis of the initial bias when the noise index requirement of the optical fiber amplifier is not met, so as to ensure that the noise index requirement of the optical fiber amplifier can be continuously met; the noise figure requirement of the optical fiber amplifier can be: the noise figure is lower than a preset noise figure value, and the noise figure margin is smaller 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 a person skilled in the art according to actual conditions.

On the basis of the bias adjustment, inputting the minimum input power corresponding to the minimum target gain and the minimum input power corresponding to the maximum target gain into the optical fiber amplifier again, starting to gradually increase the input power from the minimum input power until one pump reaches the maximum current or the maximum input power corresponding to the current target gain, continuously judging whether the transient performance requirement of the optical fiber amplifier is met according to the fed back output optical power in the process of increasing the input power, and continuously adjusting the current proportion of each pump in a preset window period according to proportional integral control on the basis of the initial current proportion if the transient performance requirement of the optical fiber amplifier is not met, so as to ensure that the transient performance requirement of the optical fiber amplifier can be met; wherein, the transient performance requirement of the optical fiber amplifier can be: the transient performance index of the optical fiber amplifier is lower than a preset transient performance requirement, and the margin of the transient performance index of the optical fiber amplifier is smaller than or equal to a second preset margin value; wherein the preset transient performance requirement and the second preset margin value are set by one skilled in the art at his own discretion.

In step 105, when the optical fiber amplifier meets the noise figure requirement, the optimized bias and the optimized current proportion are used as parameters to be configured.

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

Because the current proportion and the offset of each pump are difficult to debug in single-round iteration, the noise index requirement and the transient performance requirement of the optical fiber amplifier are difficult to be met at one time, and the noise index requirement and the transient performance requirement are difficult to be simultaneously considered in each pump adjustment, in the embodiment, the noise index and the transient performance are monitored by acquiring the input optical power and the output optical power in real time, when the noise index and/or the transient performance are judged to be problematic, corresponding correction parameters are generated to finely adjust the current proportion and/or the offset of each pump, and in multi-round iteration debugging, the offset and the current proportion which can meet the noise index requirement and the transient performance requirement are finally output, so that the transient performance of the optical fiber amplifier is optimized on the basis of reducing the noise index of the optical fiber amplifier.

In the process of increasing the input power, judging whether the optical fiber amplifier meets the noise figure requirement in real time, so as to synchronously adjust the offset of each pump, and specifically comprising the following steps:

And when the noise index of the optical fiber amplifier exceeds the noise index requirement, increasing the offset of the front-stage pump or reducing the offset of the rear-stage pump until the noise index of the optical fiber amplifier is lower than the noise index requirement, and taking the adjusted offset as the optimized offset.

And when the margin of the noise index of the optical fiber amplifier is larger than a first preset margin value, reducing the offset of the front-stage pump or increasing the offset of the rear-stage pump until the margin of the noise index of the optical fiber amplifier is smaller than or equal to the first preset margin value, and taking the adjusted offset as the optimized offset.

The method comprises the steps of acquiring the value of input optical power and the value of output optical power of the optical fiber amplifier through corresponding modules, monitoring the current transient performance of the optical fiber amplifier through the value of the input optical power, correspondingly adjusting the current input optical power and the output optical power according to the current input optical power and the output optical power when judging that the transient effect occurs on an optical path, obtaining corresponding adjustment parameters according to proportional integral control, and carrying out feedback adjustment on the current proportion of each pump in a debugging window, thereby carrying out adjustment on the current proportion of each pump according to the transient performance state of the current optical fiber amplifier in real time, wherein the corresponding design is as follows:

And in the gain interval of the lowest target gain and the highest target gain, adjusting the current proportion 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 optical fiber amplifier is met, and obtaining the optimized current proportion, as shown in fig. 2, the method flow comprises the following steps:

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 input to the optical fiber amplifier, and the input power is gradually increased from the minimum input power until one of the pumps reaches the maximum current or the maximum input power corresponding to the current target gain.

In step 202, in the process of increasing the input power, the slope of the input optical power is obtained in real time according to the current input optical power.

In the process of increasing the input power, the slope of the input optical power is obtained in real time according to the current input optical power, whether the current optical fiber amplifier meets the transient performance requirement is judged according to the slope of the input optical power, and the corresponding PID parameters and/or the current proportion of each pump are adjusted in real time until the optical fiber amplifier meets the transient performance requirement.

In this embodiment, the obtained input optical power is shifted to obtain N stages, so as to ensure that the current input optical power meets the minimum number of stages required by the estimated slope of the least square method, and the estimated slope k of the optical power change is calculated according to the current input optical power of the obtained N stages and the least square method calculation formula, where the formula is as follows:

Where k is the slope of the optical power change, X _i is the i-th sequence number of the input optical power value, Y _i is the i-th input optical power scaling value, and n is the number of sample samples. Wherein, a plurality of the input optical power values are acquired according to time sequence; the shift acquisition N stages are to shift and acquire the input optical power through N stages of shift registers, so that the requirement of a least square method is met.

In step 203, when the slope of the input optical power is greater than or equal to the preset lower-wave transient state decision threshold and less than or equal to the preset upper-wave transient state decision threshold, the original PID parameters are adjusted until the optical fiber amplifier meets the transient performance requirement, and if the optical fiber amplifier cannot meet the transient performance requirement by adjusting the original PID parameters, the current proportion 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 optical fiber amplifier meets the transient performance requirement.

In step 204, when the slope of the input optical power is greater than the preset uplink transient decision threshold, the optical fiber amplifier triggers an uplink transient event, and does not meet the transient performance requirement, the uplink parameter is adjusted until the optical fiber amplifier meets the transient performance requirement, and if the optical fiber amplifier cannot meet the transient performance requirement by adjusting the uplink parameter, the current proportion 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 optical fiber amplifier meets the transient performance requirement.

In step 205, when the slope of the input optical power is smaller than the preset down-wave transient state decision threshold, the optical fiber amplifier triggers a down-wave transient state event, and does not meet the transient state performance requirement, the down-wave parameters are adjusted until the optical fiber amplifier meets the transient state performance requirement, if the optical fiber amplifier cannot meet the transient state performance requirement by adjusting the down-wave parameters, the current proportion 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 optical fiber amplifier meets the transient state performance requirement.

The current proportion 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 optical fiber amplifier meets the transient performance requirement, as shown in fig. 3, the method flow comprises:

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

In this embodiment, when each physical pumping current does not reach the maximum current, a target gain i is set, and a slope k_i and an intercept b_i are obtained by linear fitting through traversing logical pumping values (pump_logic_dac) corresponding to different input optical powers (inputPwr _mw); finally, the feedforward parameters of the gain_mw_n are scaled according to the previous step to obtain k_1 and b_1, k_2 and b_2, etc. According to K_1, K_2 corresponding to the target gain, carrying out linear fitting on K_n to obtain a slope K_k and an intercept K_b; according to B_1, B_2, corresponding to the target gain, B_n, linear fitting to obtain an intercept B_k and an intercept B_b, so that the predicted current value of each pump is obtained through preliminary calculation, the feedforward component is obtained, feedback adjustment can be carried out on the basis of the pre-current value subsequently, the feedforward component can ensure the quick response of the corresponding optical fiber amplifier, and the feedback component can ensure the precision of the corresponding optical fiber amplifier.

In step 302, delay control is performed on the current input optical power and the current output optical power in a preset window period to obtain a delay overshoot parameter, a PID parameter is obtained in real time according to the current input optical power and the output optical power, and a feedback component is obtained according to the delay overshoot parameter and the PID parameter.

In this embodiment, delay control is performed on the current input optical power and the current output optical power in a preset window period, and PID parameters are obtained in real time according to the current input optical power and the current output optical power, and then current proportion distribution of each pump is performed according to the delay overshoot parameters and the PID parameters, so as to suppress the transient undershoot amplitude.

In step 303, the feedforward component and the feedback component are summed to obtain the output optical power of the optical fiber amplifier on logic, the current proportion of each pump is distributed and adjusted according to the output optical power of the optical fiber amplifier on logic, and the optical fiber amplifier after distribution and adjustment is judged to meet the transient performance requirement.

In this embodiment, the output optical power of the optical fiber amplifier is a reference value x, the current ratio of each pump is k, and the offset of each pump is b, so the corresponding power distribution of each pump is kx+b.

In step 304, when the adjusted optical fiber amplifier meets the transient performance requirement, the adjusted current ratio of each pump is used as the optimized current ratio.

In step 305, when the adjusted optical fiber amplifier does not meet the transient performance requirement, the current proportion of each pump is subjected to secondary optimization adjustment until the optical fiber amplifier meets the transient performance requirement.

The secondary optimization adjustment is to perform optimization adjustment again on the basis of the previous optimization adjustment.

And when the regulated optical fiber amplifier does not meet the transient performance requirement, carrying out secondary optimization regulation on the current proportion of each pump until the optical fiber amplifier meets the transient performance requirement, wherein the method specifically comprises the following steps of:

and when the transient performance index of the optical fiber amplifier exceeds the transient performance requirement, reducing the current proportion of the front stage pumping in all pumping or increasing the current proportion of the rear stage pumping in all pumping until the transient performance index is lower than the transient performance requirement, and taking the current proportion regulated by secondary optimization as the optimized current proportion.

And when the margin of the transient performance index of the optical fiber amplifier is larger than a second preset margin value, increasing the current proportion of the front-stage pumping in all pumping or reducing the current proportion of the rear-stage pumping in all pumping until the margin of the transient performance index is smaller than or equal to the second preset margin value, and taking the current proportion regulated by secondary optimization as the optimized current proportion.

Example 2:

Embodiment 2 of the present invention provides a control device for a low noise multi-pump EDFA according to embodiment 1, which is used for applying the control device for a low noise multi-pump EDFA according to embodiment 1, and as shown in fig. 4, includes: the system comprises a pump distribution module, a logic pump module, a feedforward control module, a feedback and judgment module, an input detection module and an output detection module, wherein:

the multiple EDFAs are sequentially connected, the input end of the first EDFA is connected with the input detection module, and the output end of the last EDFA is connected with the output detection module; the input detection module is used for acquiring the current input optical power, and the output detection module is used for acquiring the current output optical power.

As shown in fig. 4, in the optical path of the multi-pump cascade in fig. 4, n EDFAs are provided, each EDFA is connected with a corresponding pump, and the number of pumps is also n, where n is a positive integer greater than 2.

In this embodiment, the input detection module is configured to drive a corresponding input detection circuit, and is configured to obtain a scaling value of an input optical power input to the optical fiber amplifier, update the scaling value of the input optical power according to a sequence of a subsequent first-in last-out, and provide a data source to be processed for a subsequent feedforward control module and a feedback and determination module, where the feedforward control module and the feedback and determination module adjust current ratios of each pump according to the data source.

The output detection module is used for driving a corresponding output detection circuit and calibrating corresponding output optical power, the output detection module is also used for acquiring a calibration value of the output optical power, updating the calibration value of the output optical power according to a sequence of a subsequent first-in last-out, and providing a data source to be processed for a subsequent feedforward control module and a feedback and judgment module, and the feedforward control module and the feedback and judgment module regulate the current proportion of each pump according to the data source.

The pump distribution module is connected with a plurality of pumps respectively, each pump is connected with a corresponding EDFA, the pump distribution module, the logic pump module and the feedback and judgment module are sequentially connected, the feedback and judgment module is connected with the input detection module and the output detection module respectively, and the input detection module, the feedforward control module and the logic pump module are sequentially connected.

In each iteration: the feedforward control module is used for obtaining a feedforward component according to the current input optical power and the current target gain and sending the feedforward component to the logic pumping module; the feedback and judging module is used for judging whether the transient performance requirement of the optical fiber amplifier is met or not according to the current input optical power and the current output optical power, obtaining a corresponding feedback component and sending the feedback component to the logic pumping module; the logic pumping module is used for adding the feedforward component and the feedback component to obtain a numerical control conversion signal of the pumping output quantity, restraining the pumping output quantity in the interval of the maximum total current value and the minimum total current value of all pumps, and sending the numerical control conversion signal of the restrained pumping output quantity to the pumping distribution module; the pumping distribution module is used for carrying out corresponding current distribution on each pumping according to the numerical control conversion signal, the current proportion and the bias quantity of each pumping and the maximum current value and the minimum current value of each pumping.

The feedforward control module is used for obtaining the current input optical power according to the input detection module, calculating to obtain feedforward components according to the current input optical power and the target gain, obtaining the predicted current value of each current through the feedforward components, and improving the response speed of the optical fiber amplifier; the feedback and judging module is used for processing the input optical power calibration value, estimating the slope of the input optical power according to a least square method, judging whether a transient effect exists in an optical path according to the slope of the input optical power, and when judging that the transient effect exists, performing delay control on the input optical power calibration value and the output optical power calibration value within a preset window period to obtain a delay overshoot parameter, obtaining a PID parameter according to the current input optical power and the current output optical power in real time, and taking the delay overshoot parameter and the PID parameter as feedback components.

The logic pumping module adds the feedforward component and the feedback component to obtain a numerical control conversion signal of the pumping output, the pumping output is required to be subjected to constraint adjustment according to the maximum total current value and the minimum total current value of all the pumps, the pumping output is prevented from exceeding the maximum total current value or being lower than the minimum total current value, when the maximum total current value is exceeded, the pumping output constraint is adjusted to the maximum total current value of all the pumps, when the minimum total current value is lower, the pumping output constraint is adjusted to the minimum total current value of all the pumps, and then the numerical control conversion signal of the adjusted pumping output is sent to the pumping distribution module.

The pump distribution module multiplies the received numerical control conversion signal x of the pump output quantity by the preset current proportion k of each pump, and adds the preset bias quantity b of each pump to obtain a current value kx+b required to be distributed to each pump, and then constrains the current value kx+b of each pump in a section of a maximum current value and a minimum current value corresponding to each pump, so that the distributed current of the pump is prevented from being larger than a maximum value, the pump is prevented from being burnt out, or the distributed current of the pump is prevented from being smaller than the minimum value, and the pump is ensured to work in a linear region above a threshold current instead of a non-light cut-off region.

As shown in fig. 5, the feedback and decision module includes a feedback control module and a transient decision module, where:

The transient state judgment module, the feedback control module and the logic pumping module are connected in sequence, the transient state judgment module is connected with the input detection module and the output detection module respectively, and the feedback control module is connected with the input detection module and the output detection module respectively.

The transient state judging module is used for obtaining the slope of the input optical power according to the current input optical power, judging whether the transient state performance requirement of the optical fiber amplifier is met according to the slope of the input optical power, carrying out delay control on the current input optical power and the current output optical power in a preset window period to obtain a delay overshoot parameter, obtaining a PID parameter in real time according to the current input optical power and the output optical power, and sending the delay overshoot parameter and the PID parameter to the feedback control module.

The feedback control module is used for performing closed-loop locking on the current target gain according to the current input optical power and the current output optical power, obtaining a feedback component according to the delay overshoot parameter and the PID parameter, and sending the feedback component to the logic pumping module in a separated mode.

Example 3:

the embodiment 3 of the invention provides an actual execution flow of a control method of a low-noise multi-pump EDFA on the basis of the embodiment 1 and the embodiment 2, which is used for displaying the corresponding control method more intuitively.

Step1, initializing parameters:

the initial current ratio of each pump is set, for example, the first stage pump ratio is 100%, the second stage pump ratio is 85%, and each initial offset is set to 0.

Setting reference PID initialization parameters (pid_p, pid_i, pid_d), setting preset downlink transient decision threshold and preset uplink transient decision threshold add_thr and drop_thr, and initializing preset window periods enter_window and exit_window respectively, and setting initial delay overshoot parameters (add_dly, drop_dly) and initial PID parameters (add_P_delta, add_I_delta, add_D_delta, drop_P_delta, drop_I_delta, drop_D_delta) to 0.

And 2, scaling the pump scale factor and the pre-bias amount.

And 2-1, respectively setting the highest target gain and the lowest target gain, and gradually increasing the input optical power from the minimum input optical power in the corresponding light inlet range until one pump reaches the maximum current. In the above-described process of increasing the optical power, the offset (offset_i) of each pump is adjusted so that the noise figure satisfies the noise figure requirement.

When the noise figure exceeds the noise figure requirement, increasing the offset of the pump of the front stage in the cascade pump or reducing the offset of the pump of the rear stage; when the margin of the noise figure is larger than the first preset margin value, the bias of the pump of the front stage is reduced or the bias of the pump of the rear stage is increased.

Step 2-2, debugging transient performance of the optical fiber amplifier at the highest and lowest target gains respectively, and debugging the transient performance through debugging parameters in a feedforward control module and a transient judgment module, wherein the parameters in the feedforward control module and the transient judgment module specifically comprise: feedforward component, delay overshoot parameter, and PID parameter. When the parameters can meet the transient performance under each condition, the calibration is completed; if not, executing the step 2-3.

And 2-3, adjusting the current proportion (ratio_i) of each pump to enable the transient index of the optical fiber amplifier to meet the requirement. When the transient performance index exceeds the transient performance requirement, reducing the current proportion of the pumping of the front stage in the cascade pumping or increasing the current proportion of the pumping of the rear stage; when the margin of the transient performance index is larger than the second preset margin value, the current proportion of the pumping of the front stage is increased or the current proportion of the pumping of the rear stage is reduced.

And 2-4, checking whether the current proportion and the bias quantity of each pump can meet the noise figure requirement under the test condition of the step 2-1. If yes, the calibration is completed, if not, iteration is started from the step 2-1, and the current proportion and the bias amount of each pump are finely adjusted.

And 3, amplifying Spontaneous Emission (ASE) power calibration.

Amplified spontaneous emission power scaling is a necessary step for the optical fiber amplifier to lock the target gain, and noise components and signal components in the output power can be obtained through the step, so that the power of the signal components can be ensured to meet the requirement.

Because the self-excitation radiation generated by the amplification of the optical fiber amplifier overlaps with the signal wave band, the photoelectric detector cannot distinguish the signal power from the ASE power, and the ASE power in the output light needs to be calibrated through a spectrometer (Optical spectrum Analyzer, abbreviated as OSA), so that the signal light power in the output light power is ensured to obtain proper gain.

Step 3-1, setting the working mode as AGC, and setting the VOA as attenuation mode by the variable gain optical fiber amplifier comprising the adjustable optical attenuator (variable optical attenuator, abbreviated as VOA).

Step 3-2, respectively taking the minimum input optical power corresponding to the three gain points, and recording the current ase_mw according to the following formula by adjusting ASE scaling parameters, namely, ase_k or ase_b, so that the gain reported by the spectrometer is equal to the set gain:

ase_mw＝ase_k*dB2mw(gain_set)+ase_b；

dB2mw(gain_set)＝10^(gain_set/10)；

step 3-3, based on the three sets of data of ase_mw and dB2mw (gain_set) obtained in step 3-2, the ASE scaling parameters, ase_k and ase_b, are obtained using a linear fit.

And 3-4, verifying the calibration accuracy of ASE, checking whether the deviation between the reported gain and the set gain of the spectrometer is smaller than the requirement by traversing the light inlet power under the gain of the size, if so, completing the calibration required, if not, not satisfying the inspection test condition, and starting to re-fit ASE calibration parameters from the step 3-1.

And 4, feedforward scaling of the logic pumping module.

The feedforward component of the logic pumping module can rapidly output the current proportion of the pumping corresponding to the gain according to the input optical power detection value under the current gain, thereby realizing the purpose of rapid pumping adjustment and mainly playing a role in the scenes of transient control of the input optical power or gain switching and the like.

Step 4-1, setting the working mode as AGC, and setting the VOA into attenuation mode by the variable gain EDFA containing the VOA.

Step 4-2, setting 3 target gains respectively, taking 4 input optical powers under each gain, and when the target gains are locked, if the current in each optical fiber amplifier reaches the maximum current, reducing the input optical power until the optical fiber amplifiers exit the maximum current state; otherwise, the current logic pump (pump_logic_dac) and the input optical power value dB2mw (input_pwr) are recorded according to the following formula:

pump_logic_dac＝K*dB2mw(input_pwr)+B；

dB2mw(input_pwr)＝10^(input_pwr/10)；

According to 4 groups of logic pump and input optical power value data under each gain, the current feedforward scaling parameters K_1 and B_1 are obtained in a linear fitting mode, and the feedforward scaling parameters K_2, B_2 and K_3 and B_3 under the other two gains are obtained in a similar way.

Step 4-3, linear fitting is carried out on the feedforward scaling parameters K_1, K_2 and K_3 under the three gain points obtained in the step 4-2 and the input optical power values, so as to obtain feedforward scaling parameters K_k and K_b; and (3) linearly fitting the feedforward scaling parameters B_1, B_2 and B_3 under the three gain points obtained in the step (4-2) with the input optical power values to obtain feedforward scaling parameters B_k and B_b.

And 4-4, verifying the calibration accuracy of the feedforward, under the condition of closing feedback enabling, verifying whether the deviation between the reported gain and the set gain of the optical fiber amplifier is smaller than the requirement or not by traversing the light inlet power under the gain of the size, if so, completing the calibration meeting the requirement, if not, not meeting the checking and testing condition, and re-fitting the feedforward calibration parameters from the step 4-1.

And 5, checking noise figure and transient performance.

Since ASE power scaling will result in a corresponding increase in the current value of the logic pump module at the same gain, the noise figure will change less on a step 2 basis, requiring verification of the noise figure. When the verification fails, step 2 needs to be performed iteratively.

Since the feedforward scaling accuracy of the logic pump module directly affects the transient performance, it is necessary to verify the transient performance. And when the verification is not passed, debugging parameters such as delay overshoot parameters, PID parameters and the like in the transient state judgment module to optimize transient state performance.

In summary, the control method and apparatus for low noise multi-pump EDFA provided in embodiments 1,2 and 3 can bring the following advantages:

1. The invention simplifies the closed-loop control of a plurality of cascade pump lasers into the closed-loop locking of one logic pump laser, greatly simplifies the feedforward calibration and ASE calibration work of a plurality of pump lasers under different gains, solves the problems of optical power oscillation and pump power consistency possibly existing in the control of a plurality of pumps, and is convenient for the debugging and production of an EDFA module.

2. The invention fully considers the difference between factors influencing noise index and transient effect, directly controls the relative value of logic pump when the light-in power is larger and the initial proportion component of pump when the light-in power is smaller by adjusting the proportion factor and pre-bias quantity of each pump laser, realizes the optimization of the noise index of the EDFA module while ensuring the transient performance, thereby further improving the signal to noise ratio of the optical network.

3. The invention fully utilizes the advantages of parallel computation of the FPGA, has the characteristics of rapid detection power and real-time parallel control, comprehensively optimizes the transient performance in an optical network by adjusting the pump proportion and the offset and combining the transient overshoot time, PID (proportion integration differentiation) adjustment parameters and input/output sampling delay in transient judgment and control, and solves the problem of light surge impact caused by the EDFA transient.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.

Claims (10)

1. A method of controlling a low noise multi-pump EDFA comprising:

Setting initial current proportion and initial bias of each pump in the optical fiber amplifier;

Setting the highest target gain and the lowest target gain of the optical fiber amplifier, and inputting the initial current proportion and the initial bias quantity into a first round of iteration to optimize the bias quantity and the current proportion of the pump through at least one iteration calculation;

Each iteration includes: adjusting the offset of each pump in a gain interval formed by the lowest target gain and the highest target gain until the noise index requirement of the optical fiber amplifier is met, and obtaining an optimized offset; in a gain section formed by the lowest target gain and the highest target gain, adjusting the current proportion 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 optical fiber amplifier is met, and obtaining an optimized current proportion; checking whether the optical fiber amplifier meets the noise figure requirement in a gain interval formed by the lowest target gain and the highest target gain;

When the optical fiber amplifier meets the noise figure requirement, the optimized bias and the optimized current proportion are used as parameters for configuration;

and when the optical fiber amplifier does not meet the noise figure requirement, inputting the optimized bias quantity and the optimized current proportion into the next iteration.

2. The method for controlling a low noise multi-pump EDFA according to claim 1, wherein the adjusting the offset of each pump in the gain section formed by the lowest target gain and the highest target gain until the noise figure requirement of the optical fiber amplifier is met, and obtaining the optimized offset specifically includes:

Respectively inputting the minimum input power corresponding to the minimum target gain and the minimum input power corresponding to the maximum target gain into the optical fiber amplifier, and gradually increasing the input power from the minimum input power until one pump reaches the maximum current or the maximum input power corresponding to the current target gain; in the process of increasing the input power, judging whether the optical fiber amplifier meets the noise index requirement in real time, so that the bias of each pump is synchronously adjusted until the optical fiber amplifier meets the noise index requirement.

3. The method for controlling a low noise multi-pump EDFA according to claim 2, wherein in the process of increasing the input power, determining in real time whether the optical fiber amplifier meets the noise figure requirement, so as to synchronously adjust the bias of each pump, comprises:

When the noise index of the optical fiber amplifier exceeds the noise index requirement, increasing the offset of the front-stage pump or reducing the offset of the rear-stage pump until the noise index of the optical fiber amplifier is lower than the noise index requirement, and taking the adjusted offset as the optimized offset;

And when the margin of the noise index of the optical fiber amplifier is larger than a first preset margin value, reducing the offset of the front-stage pump or increasing the offset of the rear-stage pump until the margin of the noise index of the optical fiber amplifier is smaller than or equal to the first preset margin value, and taking the adjusted offset as the optimized offset.

4. The method of claim 1, wherein the adjusting the current ratio of each pump according to the current target gain, the current input optical power and the current output optical power in the gain section formed by the lowest target gain and the highest target gain until the transient performance requirement of the optical fiber amplifier is met, and obtaining the optimized current ratio specifically comprises:

Respectively inputting the minimum input power corresponding to the minimum target gain and the minimum input power corresponding to the maximum target gain into the optical fiber amplifier, and gradually increasing the input power from the minimum input power until one pump reaches the maximum current or the maximum input power corresponding to the current target gain;

In the process of increasing the input power, the slope of the input optical power is obtained in real time according to the current input optical power, whether the current optical fiber amplifier meets the transient performance requirement is judged according to the slope of the input optical power, and the corresponding PID parameters and/or the current proportion of each pump are adjusted in real time until the optical fiber amplifier meets the transient performance requirement.

5. The method of claim 4, wherein the determining whether the current optical fiber amplifier meets the transient performance requirement according to the slope of the input optical power, and simultaneously adjusting the PID parameters and/or the current ratios of the pumps in real time until the optical fiber amplifier meets the transient performance requirement, specifically comprises:

When the slope of the input optical power is larger than or equal to a preset downlink transient judgment threshold and smaller than or equal to a preset uplink transient judgment threshold, adjusting original PID parameters until the optical fiber amplifier meets transient performance requirements, and if the optical fiber amplifier cannot meet the transient performance requirements by adjusting the original PID parameters, synchronously adjusting the current proportion of each pump according to the current target gain, the current input optical power and the current output optical power until the optical fiber amplifier meets the transient performance requirements;

When the slope of the input optical power is larger than a preset uplink transient judgment threshold, triggering an uplink transient event by the optical fiber amplifier, and not meeting the transient performance requirement, adjusting the uplink parameter until the optical fiber amplifier meets the transient performance requirement, and if the optical fiber amplifier can not meet the transient performance requirement by adjusting the uplink parameter, synchronously adjusting the current proportion of each pump according to the current target gain, the current input optical power and the current output optical power until the optical fiber amplifier meets the transient performance requirement;

When the slope of the input optical power is smaller than a preset down-wave transient state judgment threshold, the optical fiber amplifier triggers a down-wave transient state event, the transient state performance requirement is not met, the down-wave parameters are adjusted until the optical fiber amplifier meets the transient state performance requirement, if the down-wave parameters cannot be adjusted to enable the optical fiber amplifier to meet the transient state performance requirement, the current proportion 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 optical fiber amplifier meets the transient state performance requirement.

6. The method of claim 4, wherein the step of obtaining the slope of the input optical power in real time according to the current input optical power during the step of increasing the input power comprises:

and obtaining the slope of the optical power change according to the input optical power, wherein the formula is as follows:

Where k is the slope of the optical power change, X _i is the i-th sequence number of the input optical power value, Y _i is the i-th input optical power scaling value, and n is the number of sample samples.

7. The method of claim 5, wherein the step of synchronously 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 optical fiber amplifier meets the transient performance requirement comprises:

acquiring a feedforward component according to the current input optical power and the current target gain in real time;

Delay control is carried out on the current input optical power and the current output optical power in a preset window period to obtain delay overshoot parameters, PID parameters are obtained in real time according to the current input optical power and the output optical power, and feedback components are obtained according to the delay overshoot parameters and the PID parameters;

Summing the feedforward component and the feedback component, obtaining the output optical power of the optical fiber amplifier on logic, distributing and adjusting the current proportion of each pump according to the output optical power of the optical fiber amplifier on logic, and judging whether the distributed and adjusted optical fiber amplifier meets the transient performance requirement;

When the regulated optical fiber amplifier meets the transient performance requirement, the current proportion of each pump after regulation is used as the optimized current proportion;

and when the regulated optical fiber amplifier does not meet the transient performance requirement, carrying out secondary optimization regulation on the current proportion of each pump until the optical fiber amplifier meets the transient performance requirement.

8. The method of claim 7, wherein when the adjusted fiber amplifier does not meet the transient performance requirement, performing a secondary optimization adjustment on the current ratio of each pump until the fiber amplifier meets the transient performance requirement, specifically comprising:

When the transient performance index of the optical fiber amplifier exceeds the transient performance requirement, reducing the current proportion of the front stage pumping in all pumping or increasing the current proportion of the rear stage pumping in all pumping until the transient performance index is lower than the transient performance requirement, and taking the current proportion regulated by secondary optimization as the optimized current proportion;

And when the margin of the transient performance index of the optical fiber amplifier is larger than a second preset margin value, increasing the current proportion of the front-stage pumping in all pumping or reducing the current proportion of the rear-stage pumping in all pumping until the margin of the transient performance index is smaller than or equal to the second preset margin value, and taking the current proportion regulated by secondary optimization as the optimized current proportion.

9. A control device for a low noise multi-pump EDFA, for applying a control method for a low noise multi-pump EDFA according to any of claims 1-8, comprising: the system comprises a pump distribution module, a logic pump module, a feedforward control module, a feedback and judgment module, an input detection module and an output detection module, wherein:

The multiple EDFAs are sequentially connected, the input end of the first EDFA is connected with the input detection module, and the output end of the last EDFA is connected with the output detection module; the input detection module is used for acquiring the current input optical power, and the output detection module is used for acquiring the current output optical power;

The pump distribution module is connected with a plurality of pumps respectively, each pump is connected with a corresponding EDFA, the pump distribution module, the logic pump module and the feedback and judgment module are sequentially connected, the feedback and judgment module is connected with the input detection module and the output detection module respectively, and the input detection module, the feedforward control module and the logic pump module are sequentially connected;

In each iteration: the feedforward control module is used for obtaining a feedforward component according to the current input optical power and the current target gain and sending the feedforward component to the logic pumping module; the feedback and judging module is used for judging whether the transient performance requirement of the optical fiber amplifier is met or not according to the current input optical power and the current output optical power, obtaining a corresponding feedback component and sending the feedback component to the logic pumping module; the logic pumping module is used for adding the feedforward component and the feedback component to obtain a numerical control conversion signal of the pumping output quantity, restraining the pumping output quantity within the interval of the maximum total current value and the minimum total current value of all pumps, and sending the numerical control conversion signal of the restrained pumping output quantity to the pumping distribution module; the pump distribution module is used for carrying out corresponding current distribution on each pump according to the received numerical control conversion signal, the current proportion and the bias quantity of each pump and the maximum current value and the minimum current value of each pump.

10. The control device of claim 9, wherein the feedback and decision module comprises a feedback control module and a transient decision module, wherein:

The transient state judgment module, the feedback control module and the logic pumping module are connected in sequence, the transient state judgment module is connected with the input detection module and the output detection module respectively, and the feedback control module is connected with the input detection module and the output detection module respectively;

The transient state judging module is used for obtaining the slope of the input optical power according to the current input optical power, judging whether the transient state performance requirement of the optical fiber amplifier is met according to the slope of the input optical power, carrying out delay control on the current input optical power and the current output optical power in a preset window period to obtain a delay overshoot parameter, obtaining a PID parameter in real time according to the current input optical power and the output optical power, and sending the delay overshoot parameter and the PID parameter to the feedback control module;

The feedback control module is used for performing closed-loop locking on the current target gain according to the current input optical power and the current output optical power, obtaining a feedback component according to the delay overshoot parameter and the PID parameter, and sending the feedback component to the logic pumping module in a separated mode.