A method for optical fiber dispersion compensation adaptive amplification and its device

Abstract

The present application relates to the field of optical communication technology, in particular to a kind of optical fiber dispersion compensation adaptive amplification method and device thereof, comprising: obtaining the dispersion compensation value of dispersion compensation module;According to the total gain of dispersion compensation module, the dispersion compensation value is redistributed to multiple fiber amplifiers;According to the gain of each fiber amplifier after redistribution, the first expected attenuation value of the variable optical attenuator arranged in each fiber amplifier is calculated respectively, and the attenuation compensation amount of each variable optical attenuator is calculated according to the dispersion compensation value;According to the first expected attenuation value and attenuation compensation amount, the second expected attenuation value is calculated;According to the probe power of the first input end of variable optical attenuator and the probe power of the first output end, the actual attenuation value is calculated;Actual attenuation value and second expected attenuation value are compared, if consistent, then stop adjusting variable optical attenuator;Otherwise, continue to adjust.

Description

Technical Field

[0001] This invention relates to the field of optical communication technology, and in particular to a method and apparatus for adaptive amplification with optical fiber dispersion compensation. Background Technology

[0002] Currently, dispersion compensation modules are mainly divided into fixed dispersion compensation modules and variable dispersion compensation modules. Both are designed to address the problem in high-speed, high-bandwidth, long-distance communication systems where differences in refractive index lead to varying propagation speeds at different transmission bands, causing the accumulation of fiber dispersion values ​​and resulting in signal pulse broadening, leading to severe inter-symbol interference (ISI). Fixed dispersion compensation modules can only address fixed dispersion, while variable dispersion modules can handle different dispersion values. However, variable modules cannot reflect real-time changes in dispersion compensation within the transmission system, exhibiting a lag in dispersion compensation, which can lead to errors in severe cases. Furthermore, the introduction of dispersion compensation modules can degrade the signal-to-noise ratio and noise figure of the original transmission system.

[0003] Currently, the problem with using variable dispersion modules is that they cannot reflect the dispersion changes of the transmission system in real time. On the other hand, the introduction of variable dispersion compensation modules can lead to gain flattening and deterioration of the noise performance of the optical transmission system.

[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 problems to be solved by this invention are: the variable dispersion compensation module cannot reflect the dispersion changes of the transmission system in real time; and the introduction of the variable dispersion compensation module will lead to the degradation of the gain flatness and noise performance of the optical transmission system.

[0006] The present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for adaptive amplification with optical fiber dispersion compensation, comprising:

[0008] Obtain the dispersion compensation value from the dispersion compensation module;

[0009] The total gain of the dispersion compensation module is redistributed to multiple fiber amplifiers based on the dispersion compensation value.

[0010] Based on the gain after reallocation of each fiber amplifier, the first expected attenuation value of the variable optical attenuator set in each fiber amplifier is calculated, and the attenuation compensation amount of each variable optical attenuator is calculated based on the dispersion compensation value; the second expected attenuation value is calculated based on the first expected attenuation value and the attenuation compensation amount.

[0011] The actual attenuation value is calculated based on the detection power at the first input terminal and the detection power at the first output terminal of the variable optical attenuator.

[0012] The actual attenuation value is compared with the second expected attenuation value. If they match, the adjustment of the variable optical attenuator is stopped; otherwise, the actual attenuation value of the variable optical attenuator continues to be adjusted.

[0013] Preferably, when the number of fiber amplifiers is two, the fiber amplifiers include a first fiber amplifier and a second fiber amplifier; wherein, the gain of the first fiber amplifier after reallocation is the first gain, and the gain of the second fiber amplifier after reallocation is the second gain;

[0014] The step of redistributing the total gain of the dispersion compensation module to multiple fiber amplifiers based on the dispersion compensation value specifically includes:

[0015] The dispersion compensation value is determined to be in the interval according to the dispersion compensation threshold DCM_Thr. If the dispersion compensation value is less than or equal to DCM_Thr, the dispersion compensation value is in the first interval. If the dispersion compensation value is greater than DCM_Thr, the dispersion compensation value is in the second interval.

[0016] When the gain slope of the dispersion compensation module is set to 0, if the dispersion compensation value is in the first interval, the first gain of the first fiber amplifier is the first threshold gain; the second gain of the second fiber amplifier is the second threshold gain.

[0017] If the dispersion compensation value is in the second interval, the first threshold gain and the second threshold gain will be updated.

[0018] Preferably, when the gain slope of the dispersion compensation module is not set to 0, the allocation values ​​of the first gain and the second gain specifically include:

[0019] When the dispersion compensation value is in the first interval, the first gain of the first fiber amplifier is the third threshold gain; the second gain of the second fiber amplifier is the fourth threshold gain.

[0020] When the dispersion compensation value is in the second interval, the third threshold gain and the fourth threshold gain will be updated.

[0021] Preferably, the detection power at the second input terminal and the detection power at the second output terminal of the first fiber amplifier are controlled by feedback closed loop.

[0022] The detection power at the third input terminal and the detection power at the third output terminal of the second fiber amplifier are controlled by feedback closed loop.

[0023] Preferably, the step of calculating the first desired attenuation value of the variable optical attenuator located in each optical fiber amplifier based on the reallocated gain of each optical fiber amplifier specifically includes:

[0024] The dispersion compensation value is a variable value. Based on the dispersion compensation threshold DCM_Thr, the dispersion compensation value is divided into a first interval and a second interval. If the dispersion compensation value is less than or equal to DCM_Thr, the dispersion compensation value is located in the first interval. If the dispersion compensation value is greater than DCM_Thr, the dispersion compensation value is located in the second interval.

[0025] When the dispersion compensation value is in the first interval, the first expected attenuation value is the first set attenuation value;

[0026] When the dispersion compensation value is in the second interval, the first expected attenuation value is the second set attenuation value.

[0027] Preferably, the first expected attenuation value is a variable value. Based on the attenuation threshold Voa_att_thr, the first expected attenuation value is divided into a first interval and a second interval. When the first expected attenuation value is less than or equal to Voa_att_thr, the first expected attenuation value is located in the first interval; when the first expected attenuation value is greater than Voa_att_thr, the first expected attenuation value is located in the second interval. When the number of optical attenuators is two, the optical attenuators include a first optical attenuator and a second optical attenuator, with the first optical attenuator located in the first fiber amplifier and the second optical attenuator located in the second fiber amplifier.

[0028] When the first desired attenuation value is within the first range, the first set attenuation value of the first optical attenuator is updated; the second set attenuation value of the second optical attenuator is updated.

[0029] When the first desired attenuation value is within the second range, the first set attenuation value of the first optical attenuator is updated; the second set attenuation value of the second optical attenuator is updated.

[0030] Preferably, the first desired attenuation values ​​of the first optical attenuator and the second optical attenuator are adjusted according to the difference Δ between the first desired attenuation values ​​of the first optical attenuator and the second optical attenuator, specifically including:

[0031] When Δ is between [0dB:0.3dB], the first set attenuation value will be updated to the first actual attenuation value; the second set attenuation value will be updated to the second actual attenuation value.

[0032] When Δ is between [0.4dB:0.6dB], the first set attenuation value will be updated to the third actual attenuation value; the second set attenuation value will be updated to the fourth actual attenuation value.

[0033] Preferably, if the actual attenuation value is inconsistent with the second expected attenuation value, the DAC value of the variable optical attenuator is adjusted so that the actual attenuation value is consistent with the second expected attenuation value.

[0034] In a second aspect, the present invention provides an optical fiber dispersion compensation adaptive amplification device, applicable to the optical fiber dispersion compensation adaptive amplification method described in the first aspect, comprising: a dispersion compensation module, multiple optical fiber amplifiers, and a control unit; the control unit is connected to the dispersion compensation module, and the control unit is used to acquire the dispersion compensation value;

[0035] The fiber amplifier includes a variable optical attenuator, and the control unit is connected to the variable optical attenuator. The control unit is used to configure the gain of the fiber amplifier and adjust the attenuation value of the variable optical attenuator.

[0036] The multiple fiber amplifiers are cascaded, and the dispersion compensation module is located between two fiber amplifiers. The input of the dispersion compensation module is connected to the preceding fiber amplifier, and the output of the dispersion compensation module is connected to the following fiber amplifier.

[0037] Preferably, the fiber amplifier further includes an erbium-doped fiber and a pump source, and the control unit is also connected to the control terminal of the pump source to drive the pump source according to the assigned gain.

[0038] The output of the pump source is connected to the erbium-doped fiber, and the erbium-doped fiber is connected to the variable optical attenuator.

[0039] The beneficial effects of the present invention are as follows: Firstly, based on the dispersion compensation value of the dispersion compensation module monitored in real time, the gain of multiple fiber amplifiers is reasonably allocated in real time, which solves the problem that the traditional control method cannot adaptively follow the dispersion compensation value of the dispersion compensation module.

[0040] Secondly, based on the dispersion compensation value of the dispersion compensation module monitored in real time, the first expected attenuation value of the variable optical attenuator of multiple fiber amplifiers is dynamically configured in real time, and the gain flatness of the transmission system is adjusted in real time. On the basis of completing dispersion compensation, the gain flatness of the transmission system is optimized.

[0041] Thirdly, in the preferred scheme, based on the dispersion compensation value of the dispersion compensation module monitored in real time, in addition to dynamically configuring the first expected attenuation value of multiple variable optical attenuators in real time, the first expected attenuation value of two variable optical attenuators is also reallocated according to the range of the difference between the first expected attenuation values ​​of multiple variable optical attenuators, in order to optimize the noise performance of the entire transmission system. Attached Figure Description

[0042] 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.

[0043] Figure 1 This is a flowchart illustrating a method for adaptive amplification with optical fiber dispersion compensation provided in an embodiment of the present invention.

[0044] Figure 2 This is a schematic diagram of experimental data when the gain slope of an adaptive amplification method for fiber dispersion compensation provided in an embodiment of the present invention is 0;

[0045] Figure 3 This is a schematic diagram of a fiber amplifier in an embodiment of the present invention, which is a fiber dispersion compensation adaptive amplification device.

[0046] Figure 4 This is a schematic diagram of the feedback control system of an adaptive amplification device for fiber dispersion compensation provided in an embodiment of the present invention. Detailed Implementation

[0047] 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.

[0048] 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.

[0049] 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 application, unless otherwise stated, "a plurality of" means two or more.

[0050] In this application, unless otherwise expressly 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 that enables signal transmission.

[0051] 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.

[0052] Example 1:

[0053] Embodiment 1 of the present invention provides a method for adaptive amplification with optical fiber dispersion compensation, such as... Figure 1 As shown, it includes:

[0054] In step 1, the dispersion compensation value of the dispersion compensation module is obtained.

[0055] In one embodiment, the dispersion compensation value can be obtained from a control unit, terminal, or server, etc. The input optical power of the light input to the dispersion compensation module is obtained through an input photodetector, and the output optical power of the light output from the dispersion compensation module is obtained through an output photodetector. Further mathematical calculations are performed on the input and output optical powers to derive the dispersion compensation value. Specific implementation steps include: data acquisition, measuring the input and output optical power using input and output photodetectors respectively; comparative measurement, comparing the ratio of the input and output optical powers after obtaining them; mathematical modeling, establishing a mathematical model to describe the relationship between dispersion and optical power based on the measurement results; error analysis, analyzing the uncertainty or error range of the measurement results; and result application, further adjusting or optimizing based on the calculated dispersion compensation value to ensure the system performance meets requirements.

[0056] In step 2, the total gain of the dispersion compensation module is redistributed to multiple fiber amplifiers according to the dispersion compensation value. The total gain of the dispersion compensation module can be set by the user.

[0057] In step 3, based on the gain after reallocation of each fiber amplifier, the first expected attenuation value of the variable optical attenuator in each fiber amplifier is calculated, and the attenuation compensation amount of each variable optical attenuator is calculated based on the dispersion compensation value; the second expected attenuation value is calculated based on the first expected attenuation value and the attenuation compensation amount.

[0058] In one embodiment, the first expected attenuation value can be Voa_att_exp1, specifically, Voa_att_exp1 = Gain_max - Gain_set; where Gain_max is the maximum gain of the dispersion compensation module, and Gain_set is the currently set gain value.

[0059] In one embodiment, the attenuation compensation amount can be Voa_comp, specifically, Voa_comp = F(Gain_set, Input_pwr, Temp); where Gain_set is the currently set gain, Input_pwr is the current input optical power, and Temp is the current housing temperature of the fiber amplifier. Gain_set corresponds to the range of dispersion compensation values; different ranges of dispersion compensation values ​​correspond to different actually set gain values ​​of Gain_set.

[0060] In one embodiment, the second expected attenuation value can be Voa_att_exp1; specifically, Voa_att_exp1 = Voa_att_exp1 + Voa_comp.

[0061] In step 4, the actual attenuation value is calculated based on the detection power at the first input terminal and the detection power at the first output terminal of the variable optical attenuator.

[0062] In one embodiment, the actual attenuation value can be Voa_att_actual, specifically, Voa_att_actual = Output_pwr1 - Input_pwr1; where Output_pwr1 is the detection power of the first output terminal and Input_pwr1 is the detection power of the first input terminal.

[0063] In step 5, the actual attenuation value is compared with the second desired attenuation value. If they match, the adjustment of the variable optical attenuator stops; otherwise, the actual attenuation value of the variable optical attenuator continues to be adjusted. Specifically, the variable optical attenuator is adjusted to the value of the Digital-to-Analog Converter (DAC). If the actual attenuation value does not match the second desired attenuation value, the DAC value of the variable optical attenuator is adjusted to make the actual attenuation value match the second desired attenuation value.

[0064] Specifically, the actual attenuation value is compared with the second expected attenuation value. If they match, the adjustment of the variable optical attenuator stops; otherwise, the actual attenuation value of the variable optical attenuator continues to be adjusted. If the actual attenuation value does not match the second expected attenuation value, the actual attenuation value of the variable optical attenuator continues to be adjusted until the analog control voltage of the variable optical attenuator reaches either the maximum or minimum voltage value, at which point the adjustment stops. If the actual attenuation value matches the second expected attenuation value, it means the variable optical attenuator is properly adjusted, and no further adjustment is needed within the monitored timeframe.

[0065] Specifically, the actual attenuation value is calculated based on the detection power at the first input and the first output of the variable optical attenuator. Closed-loop control is then applied to the first input and first output of the variable optical attenuator to lock the calculated actual attenuation value. By locking the actual attenuation value, the system can adjust it in real time to adapt to signal changes, ensuring the signal is always in optimal transmission condition. This reduces signal distortion and fluctuations, improves signal quality and stability, and optimizes the overall performance of the communication system. Furthermore, locking the actual attenuation value helps the system be compatible with multiple transmission modes and protocols, enabling dynamic adjustment and preventing potential signal problems and malfunctions.

[0066] Unlike existing technologies, this embodiment has at least the following effects:

[0067] Firstly, based on the dispersion compensation value of the dispersion compensation module monitored in real time, the gain of multiple fiber amplifiers is reasonably allocated in real time, which solves the problem that traditional control methods cannot adaptively follow the dispersion compensation value of the dispersion compensation module.

[0068] Secondly, based on the dispersion compensation value of the dispersion compensation module monitored in real time, the first expected attenuation value of the variable optical attenuator of multiple fiber amplifiers is dynamically configured in real time, and the gain flatness of the transmission system is adjusted in real time. On the basis of completing dispersion compensation, the gain flatness of the transmission system is optimized.

[0069] Thirdly, in the preferred scheme, based on the dispersion compensation value of the dispersion compensation module monitored in real time, in addition to dynamically configuring the first expected attenuation value of multiple variable optical attenuators in real time, the first expected attenuation value of two variable optical attenuators is also reallocated according to the range of the difference between the first expected attenuation values ​​of multiple variable optical attenuators, in order to optimize the noise performance of the entire transmission system.

[0070] To fully illustrate the solution provided by this invention, the details of the above method will be described in further detail below.

[0071] In this embodiment, F in each formula can represent the function F(x,y)=x+y, and G can represent the function G(x,y)=xy. The number of parameters x and y can be set as needed, but in actual application scenarios, the functions may be fine-tuned as needed.

[0072] In step 2, the total gain of the dispersion compensation module is redistributed to multiple fiber amplifiers according to the dispersion compensation value, wherein the total gain specifically includes:

[0073] In one embodiment, when the number of fiber optic amplifiers is two, the fiber optic amplifiers include a first fiber optic amplifier and a second fiber optic amplifier; a first gain is calculated based on the detection power at the second input terminal and the detection power at the second output terminal of the first fiber optic amplifier; a second gain is calculated based on the detection power at the third input terminal and the detection power at the third output terminal of the second fiber optic amplifier; wherein, the total gain is the sum of the first gain and the second gain.

[0074] Gain slope is used to describe the characteristics of gain as frequency changes. When the gain slope Tilt_set = 0, the gain remains constant or has a rate of change of 0 throughout the entire operating frequency band, which helps to ensure the flatness and consistency of the signal.

[0075] When the number of optical fiber amplifiers is two, the optical fiber amplifiers include a first optical fiber amplifier and a second optical fiber amplifier; wherein, the gain of the first optical fiber amplifier after reallocation is the first gain, and the gain of the second optical fiber amplifier after reallocation is the second gain;

[0076] The step of redistributing the total gain of the dispersion compensation module to multiple fiber amplifiers based on the dispersion compensation value specifically includes:

[0077] The dispersion compensation value is determined according to the dispersion compensation threshold DCM_Thr. If the dispersion compensation value is less than or equal to DCM_Thr, the dispersion compensation value is located in the first interval. If the dispersion compensation value is greater than DCM_Thr, the dispersion compensation value is located in the second interval.

[0078] When the gain slope of the dispersion compensation module is set to 0, if the dispersion compensation value is in the first interval, the dispersion compensation value of the first interval is the first dispersion compensation value. The first gain of the first fiber amplifier is obtained based on the expected gain set in the dispersion compensation module, the first dispersion compensation value, and the set gain slope. The second gain of the second fiber amplifier is obtained based on the dispersion compensation threshold and the set gain slope. If the dispersion compensation value is in the second interval, the first gain of the first fiber amplifier is obtained based on the expected gain set in the dispersion compensation module and the set gain slope. The second gain of the second fiber amplifier is obtained based on the dispersion compensation threshold and the set gain slope.

[0079] In one embodiment, the gain slope of the dispersion compensation module can be set to Tilt_set. When Tilt_set = 0, if the dispersion compensation value is in the first interval, the first gain of the first fiber amplifier is Gain1_set; where Gain1_set = F(Gain_set, DCM_Range1, Tilt_set); the second gain of the second fiber amplifier is Gain2_set; where Gain2_set = G(DCM_Thr, Tilt_set).

[0080] Where Gain_set represents the desired gain, DCM_Range1 represents the dispersion compensation value of the current dispersion compensation module, and Tilt_set represents the gain slope.

[0081] If the dispersion compensation value is in the second interval, the first gain of the first fiber amplifier is Gain3_set; where Gain3_set = F(Gain_set, Tilt_set); the second gain of the second fiber amplifier is Gain4_set; where Gain4_set = G(DCM_Thr, Tilt_set).

[0082] However, in practical communication systems, a non-zero gain slope can be caused by various factors, including but not limited to: system non-ideal characteristics (actual communication systems are not perfect; components and modules may exhibit nonlinearity, inconsistency, or frequency dependence, potentially causing gain variations with frequency and resulting in a non-zero gain slope); signal processing requirements (in some cases, to achieve specific signal processing functions or performance targets, a certain gain slope may need to be intentionally introduced, for example, to counteract certain adverse effects of the system or improve specific signal performance); dynamic adjustment and optimization (as the communication system operates and is used, its performance may change. By monitoring and adjusting the gain slope, system performance can be dynamically optimized to ensure signal quality remains within the desired range); and configurability and flexibility (in some applications, a degree of configurability and flexibility may be required to adjust the gain slope according to different needs and scenarios).

[0083] Therefore, although the signal remains stable when the gain slope Tilt_set = 0, in practical applications, the gain slope may not be equal to 0 due to the reasons mentioned above. By adjusting the gain slope, system performance can be optimized, signal quality improved, or specific communication requirements can be met.

[0084] When the gain slope of the dispersion compensation module is not set to 0, the allocation values ​​of the first gain and the second gain specifically include: when the dispersion compensation value is in the first interval, the first gain of the first fiber amplifier is obtained based on the absolute value of the expected gain, the first dispersion compensation value, and the gain slope calculated in the dispersion compensation module; the second gain of the second fiber amplifier is obtained based on the absolute value of the dispersion compensation threshold and the gain slope calculated; when the dispersion compensation value is in the second interval, the first gain of the first fiber amplifier is obtained based on the absolute value of the expected gain and the gain slope set in the dispersion compensation module; the second gain of the second fiber amplifier is obtained based on the absolute value of the dispersion compensation threshold and the gain slope calculated.

[0085] In one embodiment, when Tilt_set is not 0, the allocation values ​​for the first gain and the second gain specifically include:

[0086] When the dispersion compensation value is in the first interval, the first gain of the first fiber amplifier is Gain11_set; where Gain11_set = F(Gain_set, DCM_Range1, |Tilt_cal|); the second gain of the second fiber amplifier is Gain21_set; where Gain21_set = G(DCM_Thr, |Tilt_cal|).

[0087] Where Gain_set represents the desired gain, DCM_Range1 represents the dispersion compensation value of the current dispersion compensation module, and |Tilt_cal| represents the absolute value of the calculated gain slope. |Tilt_cal| = Tilt_set * K, where K is a value obtained from calibration and is related to the total gain set.

[0088] When the dispersion compensation value is in the second interval, the first gain of the first fiber amplifier is Gain31_set; where Gain31_set = F(Gain_set, |Tilt_set|); the second gain of the second fiber amplifier is Gain41_set; where Gain41_set = G(DCM_Thr, |Tilt_cal|).

[0089] Based on the above method, when the gain slope is not equal to 0, the first gain and the second gain are dynamically configured at different gain points, thereby optimizing the gain flatness of the transmission system.

[0090] In addition, to ensure the system containing the dispersion compensation module can continuously monitor the input and output power of the fiber optic amplifiers and adjust their operating status in real time to ensure system stability, the detection power at the second input and second output of the first fiber optic amplifier is controlled using a feedback closed-loop control; similarly, the detection power at the third input and third output of the second fiber optic amplifier is also controlled using a feedback closed-loop control. By continuously monitoring the input and output power, the operating status of the first and second fiber optic amplifiers can be evaluated, and necessary adjustments can be made to optimize their performance.

[0091] In fiber optic amplifiers, gain allocation refers to distributing gain to different output ports to amplify and transmit multi-wavelength optical signals. Due to various factors such as temperature changes and aging, the gain of a fiber optic amplifier may vary. Therefore, to ensure system stability and reliability, measures need to be taken to lock the gain allocation value at a specific desired value. In this embodiment, after implementing feedback control of the first and second fiber optic amplifiers, the first gain reallocated to the first fiber optic amplifier and the second gain reallocated to the second fiber optic amplifier are locked. This ensures that the amplifiers provide stable and reliable amplification performance under various environments and conditions, thereby improving the transmission quality and reliability of the fiber optic communication system.

[0092] In step 3, the calculation of the first desired attenuation value of the variable optical attenuator located in each fiber amplifier based on the reallocated gain of each fiber amplifier specifically includes:

[0093] The dispersion compensation value is a variable value. Based on the dispersion compensation threshold DCM_Thr, the dispersion compensation value is divided into a first interval and a second interval. If the dispersion compensation value is less than or equal to DCM_Thr, the dispersion compensation value is located in the first interval. If the dispersion compensation value is greater than DCM_Thr, the dispersion compensation value is located in the second interval.

[0094] When the dispersion compensation value is in the first interval, the dispersion compensation value of the first interval is the first dispersion compensation value. The first expected attenuation value is obtained according to the expected gain set in the dispersion compensation module and the first dispersion compensation value. The first expected attenuation value can be Voa1_att_set. Voa1_att_set = F(Gain_set, DCM_Range1).

[0095] Where DCM_Range1 represents the dispersion compensation value of the current dispersion compensation module in the first interval.

[0096] When the dispersion compensation value is in the second interval, the dispersion compensation value of the second interval is the second dispersion compensation value. The first expected attenuation value is obtained according to the set expected gain and the second dispersion compensation value. The second expected attenuation value can be Voa2_att_set. Voa2_att_set = G(Gain_set, DCM_Range2).

[0097] DCM_Range2 represents the dispersion compensation value of the current dispersion compensation module when it is in the second range.

[0098] Since the first expected attenuation value is a variable value, it is divided into a first interval and a second interval based on the attenuation threshold Voa_att_thr. When the first expected attenuation value is less than or equal to Voa_att_thr, it falls within the first interval; when it is greater than Voa_att_thr, it falls within the second interval. To ensure the accuracy of the first expected attenuation value, it needs to be optimized based on the value calculated in the previous step.

[0099] When the number of optical attenuators is 2, the optical attenuator includes a first optical attenuator and a second optical attenuator, the first optical attenuator is located in a first optical amplifier, and the second optical attenuator is located in a second optical amplifier.

[0100] When the first expected attenuation value is located in the first interval, the attenuation value of the first interval is the first attenuation value. Based on the first attenuation value, the first set attenuation value of the first optical attenuator is obtained. Based on the first attenuation value and the first expected attenuation value obtained in the previous step, the second set attenuation value of the second optical attenuator is obtained. When the first expected attenuation value is located in the second interval, the attenuation value of the second interval is the second attenuation value. Based on the first attenuation value, the first set attenuation value of the first optical attenuator is obtained. Based on the second attenuation value and the first expected attenuation value obtained in the previous step, the second set attenuation value of the second optical attenuator is obtained.

[0101] In one embodiment, when the first desired attenuation value is located in the first range, the first set attenuation value of the first optical attenuator is Voa11_att_set; where Voa11_att_set = F(Voa_att_range1); the second set attenuation value of the second optical attenuator is Voa12_att_set; where Voa12_att_set = G(Voa_att_range1, Voa1_att_set).

[0102] When the first desired attenuation value is located in the second range, the first set attenuation value of the first optical attenuator is Voa21_att_set; where Voa21_att_set = F(Voa_att_range1); the second set attenuation value of the second optical attenuator is Voa22_att_set; where Voa22_att_set = G(Voa_att_range2, Voa2_att_set).

[0103] Where Voa_att_range1 is the attenuation value of the optical attenuator in the first range, and Voa_att_range2 is the attenuation value of the optical attenuator in the second range.

[0104] To further adjust the optical performance of the dispersion compensation module and achieve the requirement of gain flatness, the first expected attenuation values ​​of the first and second optical attenuators are adjusted according to the difference Δ between the first and second expected attenuation values. Specifically, when Δ is between 0dB and 0.3dB, the first set attenuation value is updated to the first actual attenuation value, wherein the first set attenuation value is subtracted from Δ to obtain the first actual attenuation value; the second set attenuation value is updated to the second actual attenuation value, wherein the first set attenuation value is added to Δ to obtain the second actual attenuation value; when Δ is between 0.4dB and 0.6dB, the first set attenuation value is subtracted from Δ / 2 to obtain the first actual attenuation value, and the first set attenuation value is added to Δ / 2 to obtain the second actual attenuation value.

[0105] When the first set attenuation value of the first optical attenuator is Voa11_att_set, and the first set attenuation value of the second optical attenuator is Voa12_att_set, and Δ is between [0dB:0.3dB], Voa11_att_set will be updated to the first actual attenuation value Voa11_att_set_calc, where Voa11_att_set_calc = Voa11_att_set - Δ; Voa12_att_set will be updated to the second actual attenuation value Voa12_att_set_calc, where Vo a12_att_set_calc = Voa11_att_set + Δ; when Δ is between [0.4dB:0.6dB], Voa11_att_set will be updated to Voa11_att_set_calc, where Voa11_att_set_calc = Voa11_att_set - Δ / 2, and Voa12_att_set will be updated to Voa12_att_set_calc; where Voa12_att_set_calc = Voa11_att_set + Δ / 2.

[0106] When the first set attenuation value of the first optical attenuator is Voa21_att_set, and the first set attenuation value of the second optical attenuator is Voa22_att_set, and Δ is between [0dB:0.3dB], Voa21_att_set will be updated to the first actual attenuation value Voa21_att_set_calc, where Voa21_att_set_calc = Voa21_att_set - Δ; Voa22_att_set will be updated to the second actual attenuation value Voa22_att_set_calc, where Vo a22_att_set_calc = Voa21_att_set + Δ; when Δ is between [0.4dB:0.6dB], Voa21_att_set will be updated to Voa21_att_set_calc, where Voa21_att_set_calc = Voa21_att_set - Δ / 2, and Voa22_att_set will be updated to Voa22_att_set_calc; where Voa22_att_set_calc = Voa21_att_set + Δ / 2.

[0107] In summary, the fiber dispersion compensation adaptive amplification method provided by the embodiments of the present invention, such as... Figure 2 As shown in one embodiment, when the gain slope Tilt_set = 0, based on the obtained dispersion compensation values ​​of the dispersion compensation module (DCM = 8dB and DCM = 12dB), and when the gain is set to Gain_set = 13dB and Gain_set = 20dB, the gain slope Tilt_calc value calculated from the actual measured optical signal wavelength data is used to adaptively adjust the attenuation value of the variable optical attenuator at different gain points. This ensures that the actual gain slope Tilt_calc meets the preset requirement of ±0.5dB while retaining a certain margin. The gain flatness value Gain_Flatness calculated from the actual measurement data meets the preset requirement of ±1dB while retaining a certain margin, thus achieving the effect of optimizing the gain slope and gain flatness.

[0108] Example 2:

[0109] This invention provides a device for adaptive amplification of fiber dispersion compensation based on embodiment 1, applicable to the method of adaptive amplification of fiber dispersion compensation described in embodiment 1, such as... Figure 3As shown, it includes: a dispersion compensation module, multiple fiber amplifiers, and a control unit; the control unit is connected to the dispersion compensation module and is used to acquire the dispersion compensation value; the fiber amplifier includes a variable optical attenuator, the control unit is connected to the variable optical attenuator, and the control unit is used to configure the gain of the fiber amplifier and adjust the attenuation value of the variable optical attenuator; the multiple fiber amplifiers are cascaded, the dispersion compensation module is located between two fiber amplifiers, the input end of the dispersion compensation module is connected to the preceding fiber amplifier, and the output end of the dispersion compensation module is connected to the following fiber amplifier.

[0110] like Figure 4 As shown, the fiber amplifier further includes an erbium-doped fiber and a pump source. The control unit is also connected to the control terminal of the pump source to drive the pump source according to the allocated gain. The output terminal of the pump source is connected to the erbium-doped fiber, and the erbium-doped fiber is connected to the variable optical attenuator.

[0111] Figure 3 The diagram illustrates a dispersion compensation module performing dispersion compensation on two fiber amplifiers in one embodiment. Dispersion compensation and gain are closely related in optical communication. Dispersion causes signal distortion during transmission, while gain is a parameter used to adjust signal strength or quality. To compensate for dispersion, a certain gain is typically added to ensure signal quality and stability after transmission. In optical communication systems, dispersion causes pulse broadening, leading to signal distortion during transmission. To reduce this effect, a dispersion compensation module provides the opposite effect of dispersion, thereby reducing or eliminating signal distortion. However, dispersion compensation cannot always completely eliminate signal distortion. To further improve signal quality, signal amplification, i.e., increasing gain, is necessary. Gain can be used to adjust signal strength or amplitude, thereby compensating for signal attenuation or distortion caused by dispersion. By appropriately setting the gain value, it can be ensured that the signal remains stable and of high quality after dispersion compensation. Therefore, in this embodiment, by using a dispersion compensation module to perform reasonable gain allocation and dispersion compensation on the fiber amplifiers, it is possible to effectively ensure that the signal remains stable and of high quality after dispersion compensation. In practical applications, the number of fiber optic amplifiers can be determined according to actual needs, and no restrictions are imposed in this embodiment.

[0112] The above description is merely 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 method for adaptive amplification with optical fiber dispersion compensation, characterized in that, include: Obtain the dispersion compensation value from the dispersion compensation module; The total gain of the dispersion compensation module is redistributed to multiple fiber amplifiers based on the dispersion compensation value. Based on the gain of each fiber amplifier after reallocation, calculate the first expected attenuation value of the variable optical attenuator located in each fiber amplifier, calculate the attenuation compensation amount of each variable optical attenuator based on the dispersion compensation value, and calculate the second expected attenuation value based on the first expected attenuation value and the attenuation compensation amount, so as to dynamically configure the variable optical attenuator according to the second expected attenuation value. The actual attenuation value is calculated based on the detection power at the first input terminal and the detection power at the first output terminal of the variable optical attenuator. The actual attenuation value is compared with the second expected attenuation value. If they match, the adjustment of the variable optical attenuator is stopped; otherwise, the adjustment of the variable optical attenuator continues. The number of fiber amplifiers is two, including a first fiber amplifier and a second fiber amplifier; wherein, the gain of the first fiber amplifier after reallocation is the first gain, and the gain of the second fiber amplifier after reallocation is the second gain; the step of reallocating the total gain of the dispersion compensation module to multiple fiber amplifiers according to the dispersion compensation value specifically includes: determining the interval to which the dispersion compensation value belongs based on the dispersion compensation threshold DCM_Thr; if the dispersion compensation value is less than or equal to DCM_Thr, the dispersion compensation value is located in the first interval; if the dispersion compensation value is greater than DCM_Thr, the dispersion compensation value is located in the second interval; when the dispersion compensation value is set... When the gain slope of the dispersion compensation module is equal to 0, if the dispersion compensation value is in the first interval, the dispersion compensation value of the first interval is the first dispersion compensation value. The first gain of the first fiber amplifier is obtained based on the expected gain set in the dispersion compensation module, the first dispersion compensation value, and the set gain slope. The second gain of the second fiber amplifier is obtained based on the dispersion compensation threshold and the set gain slope. If the dispersion compensation value is in the second interval, the first gain of the first fiber amplifier is obtained based on the expected gain set in the dispersion compensation module and the set gain slope. The second gain of the second fiber amplifier is obtained based on the dispersion compensation threshold and the set gain slope.

2. The method for adaptive amplification with fiber dispersion compensation according to claim 1, characterized in that, When the gain slope of the dispersion compensation module is not set to 0, the specific allocation values ​​of the first gain and the second gain include: When the dispersion compensation value is in the first interval, the first gain of the first fiber amplifier is obtained based on the absolute value of the expected gain, the first dispersion compensation value, and the gain slope calculated in the dispersion compensation module; the second gain of the second fiber amplifier is obtained based on the absolute value of the dispersion compensation threshold and the gain slope calculated. When the dispersion compensation value is in the second interval, the first gain of the first fiber amplifier is obtained based on the absolute value of the expected gain and the gain slope set in the dispersion compensation module; the second gain of the second fiber amplifier is obtained based on the absolute value of the dispersion compensation threshold and the gain slope.

3. The method for adaptive amplification with fiber dispersion compensation according to claim 1, characterized in that, The detection power at the second input terminal and the detection power at the second output terminal of the first fiber amplifier are controlled by feedback closed loop. The detection power at the third input terminal and the detection power at the third output terminal of the second fiber amplifier are controlled by feedback closed loop.

4. The method for adaptive amplification with fiber dispersion compensation according to claim 1, characterized in that, The step of calculating the first desired attenuation value of the variable optical attenuator located in each optical fiber amplifier based on the reallocated gain of each optical fiber amplifier specifically includes: The dispersion compensation value is a variable value. Based on the dispersion compensation threshold DCM_Thr, the dispersion compensation value is divided into a first interval and a second interval. If the dispersion compensation value is less than or equal to DCM_Thr, the dispersion compensation value is located in the first interval. If the dispersion compensation value is greater than DCM_Thr, the dispersion compensation value is located in the second interval. When the dispersion compensation value is in the first interval, the dispersion compensation value of the first interval is the first dispersion compensation value, and the first expected attenuation value is obtained according to the expected gain set in the dispersion compensation module and the first dispersion compensation value. When the dispersion compensation value is in the second interval, the dispersion compensation value of the second interval is the second dispersion compensation value, and the first expected attenuation value is obtained according to the set expected gain and the second dispersion compensation value.

5. The method for adaptive amplification with fiber dispersion compensation according to claim 4, characterized in that, The first expected attenuation value is a variable value, and the first expected attenuation value is divided into a first interval and a second interval according to the attenuation threshold Voa_att_thr. When the first expected decay value is less than or equal to Voa_att_thr, the first expected decay value is in the first interval; when the first expected decay value is greater than Voa_att_thr, the first expected decay value is in the second interval. When the number of optical attenuators is 2, the optical attenuator includes a first optical attenuator and a second optical attenuator, the first optical attenuator is located in the first optical fiber amplifier, and the second optical attenuator is located in the second optical fiber amplifier; When the first expected attenuation value is within the first interval, the attenuation value of the first interval is the first attenuation value. The first set attenuation value of the first optical attenuator is obtained based on the first attenuation value. The second set attenuation value of the second optical attenuator is obtained based on the first attenuation value and the first expected attenuation value obtained in the previous step. When the first expected attenuation value is located in the second interval, the attenuation value of the second interval is the second attenuation value. The first set attenuation value of the first optical attenuator is obtained based on the first attenuation value. The second set attenuation value of the second optical attenuator is obtained based on the second attenuation value and the first expected attenuation value obtained in the previous step.

6. The method for adaptive amplification with fiber dispersion compensation according to claim 5, characterized in that, Based on the difference Δ between the first and second optical attenuators, the first expected attenuation values ​​of the first and second optical attenuators are adjusted respectively, specifically including: When Δ is between [0dB:0.3dB], the first set attenuation value will be updated to the first actual attenuation value, wherein the first set attenuation value is subtracted from Δ to obtain the first actual attenuation value; the second set attenuation value will be updated to the second actual attenuation value, wherein the first set attenuation value is added to Δ to obtain the second actual attenuation value. When Δ is between [0.4dB:0.6dB], the first set attenuation value is subtracted from Δ / 2 to obtain the first actual attenuation value, and the first set attenuation value is added to Δ / 2 to obtain the second actual attenuation value.

7. The method for adaptive amplification with fiber dispersion compensation according to any one of claims 1-6, characterized in that, If the actual attenuation value is inconsistent with the second expected attenuation value, the DAC value of the variable optical attenuator is adjusted so that the actual attenuation value is consistent with the second expected attenuation value.

8. An apparatus for adaptive amplification with fiber dispersion compensation, applicable to the method for adaptive amplification with fiber dispersion compensation as described in any one of claims 1-7, characterized in that, include: The system includes a dispersion compensation module, multiple fiber amplifiers, and a control unit; the control unit is connected to the dispersion compensation module and is used to acquire the dispersion compensation value. The fiber amplifier includes a variable optical attenuator, and the control unit is connected to the variable optical attenuator. The control unit is used to configure the gain of the fiber amplifier and adjust the attenuation value of the variable optical attenuator. The multiple fiber amplifiers are cascaded, and the dispersion compensation module is located between two fiber amplifiers. The input of the dispersion compensation module is connected to the preceding fiber amplifier, and the output of the dispersion compensation module is connected to the following fiber amplifier.

9. The fiber dispersion compensation adaptive amplification device according to claim 8, characterized in that, The fiber amplifier also includes an erbium-doped fiber and a pump source, and the control unit is also connected to the control terminal of the pump source to drive the pump source according to the assigned gain. The output of the pump source is connected to the erbium-doped fiber, and the erbium-doped fiber is connected to the variable optical attenuator.

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