A method and related device for determining a power compensation value of an optical signal

Abstract

Embodiments of the present application disclose a method and related device for determining a power compensation value of an optical signal, which are used to improve the stability of signal transmission. The method in the embodiments of the present application includes: obtaining a first optical signal and a second optical signal, where the first optical signal is an optical signal obtained by up-converting or down-converting the second optical signal. Detecting the first optical power of each wavelength band in the first optical signal and the second optical power of each wavelength band in the second optical signal. Calculating the change amount of the first optical power of each wavelength band after the first optical signal is transmitted from the transmitting end to the receiving end according to the first optical power, and calculating the change amount of the second optical power of each wavelength band after the second optical signal is transmitted from the transmitting end to the receiving end according to the second optical power. Determining a first compensation value and a second compensation value according to the change amount of the first optical power and the change amount of the second optical power, where the first compensation value is used to compensate the total power of the first optical signal, and the second compensation value is used to compensate the power spectral slope of the first optical signal.

Description

Technical Field

[0001] This application relates to the field of optical communication, and particularly to a method for determining a power compensation value of an optical signal and related devices. Background Art

[0002] With the rapid growth of data traffic in the network, the demand for network transmission capacity is also increasing. Usually, the network transmission capacity can be improved by increasing the channel working spectral width (the number of channels), for example, expanding the original C band to the C band and the L band.

[0003] However, with the increase of the channel spectral width, in a multi-wavelength transmission system link, there is a Stimulated Raman Scattering (SRS) effect, and the transmission power of the short wavelength band will transfer to the transmission power of the long wavelength band. In the steady state without up-wave or down-wave, the power transfer between multi-wavelength signals caused by the SRS effect is stable. When up-wave or down-wave occurs, the number, distribution, and position of multi-wavelength signals will change randomly, resulting in complex changes in the power transfer between multi-wavelength signals, which may exceed the tolerance of the system, thereby reducing the stability of signal transmission. Summary of the Invention

[0004] Embodiments of this application provide a method for determining a power compensation value of an optical signal and related devices, so that the power change caused by the SRS effect during the transmission of the optical signal in the optical fiber does not exceed the tolerance of the system, and the power spectral slopes before and after up-wave or down-wave of the optical signal match, improving the stability of signal transmission.

[0005] In a first aspect, embodiments of this application provide a method for determining a power compensation value of an optical signal. The method includes the following steps.

[0006] First, obtain a first optical signal and a second optical signal. The first optical signal is an optical signal obtained by upshifting or downshifting the second optical signal. The second optical signal includes at least one wavelength signal, and at least one wavelength signal of the second optical signal is distributed in at least one wavelength band. The first optical signal includes at least one wavelength signal, and at least one wavelength signal of the first optical signal is distributed in at least one wavelength band. Among them, one wavelength signal of the first optical signal is distributed in any one wavelength band corresponding to the first optical signal, and one wavelength signal of the second optical signal is distributed in any one wavelength band corresponding to the second optical signal. Next, detect the first optical power of each wavelength band in the first optical signal and the second optical power of each wavelength band in the second optical signal. Then, calculate the change in the first optical power of each wavelength band of the first optical signal after being transmitted from the transmitting end to the receiving end according to the first optical power, and calculate the change in the second optical power of each wavelength band of the second optical signal after being transmitted from the transmitting end to the receiving end according to the second optical power. Furthermore, determine a first compensation value and a second compensation value according to the change in the first optical power and the change in the second optical power. Among them, the first compensation value is used to compensate the total power of the first optical signal, and the second compensation value is used to compensate the power spectral slope of the first optical signal.

[0007] In this embodiment, before transmitting the first optical signal, the total power of the first optical signal can be compensated according to the first compensation value, so that the power change caused by the SRS effect during the transmission of the first optical signal in the optical fiber does not exceed the tolerance of the system, improving the stability of signal transmission. Moreover, the power spectral slope of the first optical signal can also be compensated according to the second compensation value, so that the power spectral slopes of the first optical signal and the second optical signal received by the signal receiving end match, further improving the stability of signal transmission.

[0008] In some possible embodiments, the method further includes: obtaining a first coefficient and a second coefficient, where the first coefficient is associated with the transmission type of the signal, and the second coefficient is associated with the optical power transfer between every two wavelength bands. Determining the change in the first optical power of each wavelength band of the first optical signal after being transmitted from the transmitting end to the receiving end according to the first optical power includes: calculating the change in the first optical power according to the first optical power, the first coefficient, and the second coefficient. Determining the change in the second optical power of each wavelength band of the second optical signal after being transmitted from the transmitting end to the receiving end according to the second optical power includes: calculating the change in the second optical power according to the second optical power, the first coefficient, and the second coefficient. In this embodiment, a specific implementation manner for calculating the change in the first optical power and the change in the second optical power is provided, improving the feasibility of this solution.

[0009] In some possible embodiments, the method further includes: obtaining a ratio of the optical power of each wavelength band in the first optical signal to the total power of the first optical signal. Determining the first compensation value according to the first optical power change amount and the second optical power change amount includes: substituting the first optical power change amount, the second optical power change amount, and the ratio into a first formula to calculate the first compensation value. The first formula includes: wherein, C1 represents the first compensation value, i represents the serial number of the wavelength band, M represents the number of wavelength bands, Si1 represents the second optical power change amount of the wavelength band i in the second optical signal, Si2 represents the first optical power change amount of the wavelength band i in the first optical signal, and Xi represents the ratio. In this embodiment, a specific implementation manner for calculating the first compensation value is provided, which can calculate the power compensation value of the first optical signal more accurately.

[0010] In some possible embodiments, determining the second compensation value according to the first optical power change amount and the second optical power change amount includes: substituting the first optical power change amount of the first wavelength band at the head of the first optical signal, the first optical power change amount of the last wavelength band in the first optical signal, the second optical power change amount of the first wavelength band at the head of the second optical signal, and the second optical power change amount of the last wavelength band in the second optical signal into a second formula to calculate the second compensation value. The second formula includes: C2 = (S1max - S1min) - (S2max - S2min), where C2 represents the second compensation value, S1max represents the first optical power change amount of the last wavelength band in the first optical signal, S1min represents the first optical power change amount of the first wavelength band at the head of the first optical signal, S2max represents the second optical power change amount of the last wavelength band in the second optical signal, and S2min represents the second optical power change amount of the first wavelength band at the head of the second optical signal. In this embodiment, a specific implementation manner for calculating the second compensation value is provided, making the solution more practical.

[0011] In some possible embodiments, the method further includes: compensating the total power of the first optical signal according to the first compensation value, and compensating the power spectrum slope of the first optical signal according to the second compensation value.

[0012] In some possible embodiments, compensating the total power of the first optical signal according to the first compensation value includes: adjusting the pump current in the optical amplifier according to the first compensation value to adjust the output power of the first optical signal after passing through the optical amplifier. In this embodiment, a specific implementation manner for performing power compensation in combination with an optical amplifier is provided, which can accurately complete power compensation according to the first compensation value.

[0013] In some possible embodiments, compensating the power spectral slope of the first optical signal according to the second compensation value includes: adjusting the attenuation amount of the variable optical attenuator (VOA) in the optical amplifier according to the second compensation value, so as to adjust the power spectral slope of the first optical signal after passing through the optical amplifier. In this embodiment, a specific implementation manner of combining VOA for power spectral slope compensation is provided, and the power spectral slope compensation can be accurately completed according to the second compensation value.

[0014] In some possible embodiments, detecting the first optical power of each waveband in the first optical signal includes: dividing the first optical signal into optical signals of multiple wavebands through a filter. Detecting the first optical power of each waveband in the first optical signal through a power detector. Detecting the second optical power of each waveband in the second optical signal includes: dividing the second optical signal into optical signals of multiple wavebands through a filter. Detecting the second optical power of each waveband in the second optical signal through a power detector. In this embodiment, the power of each waveband can be detected by combining a filter and a power detector, improving the practicability of this solution.

[0015] In some possible embodiments, detecting the first optical power of each waveband in the first optical signal includes: detecting the first optical power of each wavelength in the first optical signal through an optical spectrum analyzer (OSA) or an optical performance monitor (OPM). Detecting the second optical power of each waveband in the second optical signal includes: detecting the second optical power of each wavelength in the second optical signal through an OSA or an OPM. In this embodiment, since the OSA and the OPM have the ability to detect signals within a specific wavelength range, there is no need to configure a filter anymore, and the output of the OSA and the OPM is still the power of each waveband signal, improving the scalability of this solution.

[0016] Second aspect, an embodiment of the present application provides a power calculation device, including: a processor, a memory, and an optical detection module, where the processor, the memory, and the optical detection module are interconnected through lines. The optical detection module is configured to: obtain a first optical signal and a second optical signal, where the first optical signal is an optical signal obtained by up-converting or down-converting the second optical signal, the second optical signal includes at least one wavelength signal, at least one wavelength signal of the second optical signal is distributed in at least one wavelength band, the first optical signal includes at least one wavelength signal, and at least one wavelength signal of the first optical signal is distributed in at least one wavelength band. Among them, one wavelength signal of the first optical signal is distributed in any one wavelength band corresponding to the first optical signal, and one wavelength signal of the second optical signal is distributed in any one wavelength band corresponding to the second optical signal. Detect the first optical power of each wavelength band in the first optical signal and the second optical power of each wavelength band in the second optical signal; The processor is configured to: determine the change amount of the first optical power of each wavelength band after the first optical signal is transmitted from the sending end to the receiving end according to the first optical power, and determine the change amount of the second optical power of each wavelength band after the second optical signal is transmitted from the sending end to the receiving end according to the second optical power. Determine a first compensation value according to the change amount of the first optical power and the change amount of the second optical power, where the first compensation value is used to compensate the total power of the first optical signal. Determine a second compensation value according to the change amount of the first optical power and the change amount of the second optical power, where the second compensation value is used to compensate the power spectrum slope of the first optical signal.

[0017] In some possible implementation manners, the processor is further configured to: obtain a first coefficient and a second coefficient, where the first coefficient is associated with the transmission type of the signal, and the second coefficient is associated with the optical power transfer between every two wavelength bands. Specifically, the processor is configured to: calculate the change amount of the first optical power according to the first optical power, the first coefficient, and the second coefficient. Calculate the change amount of the second optical power according to the second optical power, the first coefficient, and the second coefficient.

[0018] In some possible implementation manners, the processor is further configured to: obtain the ratio of the optical power of each wavelength band in the first optical signal to the total power of the first optical signal. Specifically, the processor is configured to substitute the change amount of the first optical power, the change amount of the second optical power, and the ratio into a first formula to calculate the first compensation value. The first formula includes: where C1 represents the first compensation value, i represents the serial number of the wavelength band, M represents the number of wavelength bands, Si1 represents the change amount of the second optical power of the wavelength band i in the second optical signal, Si2 represents the change amount of the first optical power of the wavelength band i in the first optical signal, and Xi represents the ratio.

[0019] In some possible embodiments, the processor is specifically configured to: substitute the first optical power change amount of the first waveband in the first optical signal, the first optical power change amount of the last waveband in the first optical signal, the second optical power change amount of the first waveband in the second optical signal, and the second optical power change amount of the last waveband in the second optical signal into the second formula to calculate the second compensation value. The second formula includes: C2 = (S1max - S1min) - (S2max - S2min), where C2 represents the second compensation value, S1max represents the first optical power change amount of the last waveband in the first optical signal, S1min represents the first optical power change amount of the first waveband in the first optical signal, S2max represents the second optical power change amount of the last waveband in the second optical signal, and S2min represents the second optical power change amount of the first waveband in the second optical signal.

[0020] In some possible embodiments, the processor is further configured to: compensate the total power of the first optical signal according to the first compensation value. Compensate the power spectrum slope of the first optical signal according to the second compensation value.

[0021] In some possible embodiments, the processor is specifically configured to: adjust the pump current in the optical amplifier according to the first compensation value to adjust the output power of the first optical signal after passing through the optical amplifier.

[0022] In some possible embodiments, the processor is specifically configured to: adjust the attenuation amount of the variable optical attenuator (VOA) in the optical amplifier according to the second compensation value to adjust the power spectrum slope of the first optical signal after passing through the optical amplifier.

[0023] In some possible embodiments, the optical detection module includes a filter and a power detector. The filter is configured to: divide the first optical signal into optical signals of multiple wavebands. Divide the second optical signal into optical signals of multiple wavebands. The power detector is configured to: detect the first optical power of each waveband in the first optical signal. Detect the second optical power of each waveband in the second optical signal.

[0024] In some possible embodiments, the optical detection module includes an optical spectrum analyzer (OSA) or an optical power monitor (OPM). The OSA or OPM is configured to: detect the first optical power of each wavelength in the first optical signal. Detect the second optical power of each wavelength in the second optical signal.

[0025] In a third aspect, an embodiment of the present application provides an optical transmission system, including a first site and a second site. The first site is configured to execute the method for determining the power compensation value of the optical signal in any of the embodiments of the first aspect above. The second site is configured to receive the optical signal output by the first site.

[0026] In some possible embodiments, the first site includes an optical amplifier site or a Reconfigurable Optical Add-Drop Multiplexer (ROADM) site.

[0027] As can be seen from the above technical solutions, the embodiments of the present application have the following advantages:

[0028] In the embodiments of the present application, the first optical signal is an optical signal obtained by wavelength up-conversion or down-conversion based on the second optical signal. The signal transmitter needs to detect the first optical power of each wavelength band in the first optical signal and the second optical power of each wavelength band in the second optical signal. Then, the first optical power change amount caused by the SRS effect of each wavelength band after the first optical signal is transmitted from the transmitter to the receiver can be calculated according to the first optical power, and the second optical power change amount caused by the SRS effect of each wavelength band after the second optical signal is transmitted from the transmitter to the receiver can be calculated according to the second optical power. Next, the first compensation value and the second compensation value are determined according to the first optical power change amount and the second optical power change amount. Furthermore, before transmitting the first optical signal, the total power of the first optical signal can be compensated according to the first compensation value, so that the power change caused by the SRS effect during the transmission of the first optical signal in the optical fiber does not exceed the tolerance of the system, improving the stability of signal transmission. Moreover, the power spectrum slope of the first optical signal can also be compensated according to the second compensation value, so that the power spectrum slopes of the first optical signal and the second optical signal received by the signal receiver match, further improving the stability of signal transmission. Description of the Drawings

[0029] Figure 1 It is a schematic structural diagram of an optical transmission system applied to the present application;

[0030] Figure 2 It is a schematic diagram of an embodiment of a method for determining the power compensation value of an optical signal in the present application;

[0031] Figure 3 It is a schematic diagram of an embodiment in which multi-wavelength signals are distributed in multiple wavelength bands;

[0032] Figure 4 It is a schematic diagram of an embodiment of optical power detection in the present application;

[0033] Figure 5 It is a schematic diagram of another embodiment of optical power detection in the present application;

[0034] Figure 6 It is a schematic diagram of an embodiment of power transfer between wavelength bands;

[0035] Figure 7 It is a schematic diagram of an embodiment of optical signal power change;

[0036] Figure 8 This is a schematic structural diagram of an optical amplifier in an embodiment of the present application;

[0037] Figure 9 This is a schematic structural diagram of a power calculation device;

[0038] Figure 10 This is a schematic structural diagram of an optical transmission system in an embodiment of the present application. Specific embodiments

[0039] The embodiments of the present application provide a method and related device for determining a power compensation value of an optical signal, so that the power change caused by the SRS effect during the transmission of the optical signal in the optical fiber does not exceed the tolerance of the system, and the power spectral slope before and after the optical signal undergoes up-wave or down-wave is matched, improving the stability of signal transmission.

[0040] It should be noted that the terms "first", "second", "third", and "fourth" in the specification, claims, and above-mentioned drawings of the present application are used to distinguish similar objects, rather than to limit a specific order or sequence. It should be understood that the above terms can be interchanged under appropriate circumstances, so that the embodiments described in the present application can be implemented in an order other than that described in the present application. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0041] Figure 1 This is a schematic structural diagram of an optical transmission system applied in the present application. The optical transmission system at least includes a first site 10 and a second site 20. Among them, the first site 10 includes an optical amplifier 101, a coupler 102, and a power detection device 103. The second site 20 includes an optical amplifier 201, a coupler 202, and a power detection device 203. As Figure 1 shown, the first site 10 can transmit multi-wavelength signals to the second site 20 through an optical fiber. The multi-wavelength signals transmitted in the optical fiber are affected by the Stimulated Raman Scattering (SRS) effect, so that the transmission power of the short wavelength band will transfer to the transmission power of the long wavelength band.

[0042] It should be understood that if there is no addition (Add) or dropping (Drop) of the current multi-wavelength signal, the power transfer between multi-wavelength signals caused by the SRS effect is stable. When addition or dropping occurs, the number, distribution, and position of multi-wavelength signals will change randomly, resulting in complex changes in the power transfer between multi-wavelength signals. Such power changes may exceed the tolerance of the system. Therefore, in the first site 10 of this application, a power detection device 103 is provided. Before the multi-wavelength signal output from the first site 10 enters the optical fiber, the power detection device 103 can pre-calculate the power change caused by the SRS effect. Furthermore, the first site 10 can compensate the transmission power of the multi-wavelength signal based on the calculation result. Thus, complex changes in the power transfer between multi-wavelength signals during transmission are avoided, and the stability of signal transmission is improved.

[0043] Specifically, the coupler 102 can split the signal output by the optical amplifier 101. One of the split signals is coupled into the optical fiber and transmitted to the second site 20. The other split signal is coupled to the power detection device 103 for calculating the power change caused by the SRS effect. The power detection device 103 calculates the power value that needs to be compensated and outputs the compensation value to the optical amplifier 101, and then the optical amplifier 101 compensates the power of the subsequent output signal. It should be understood that the coupler 102 splits the signal according to the power ratio, and the wavelengths included in each split signal are the same. For example, the coupler 102 can split the signal according to a power ratio of 99:1, with most of the signals coupled into the optical fiber and a small part of the signals reserved for detection and calculation.

[0044] It should be noted that the type of the above optical amplifier can be an erbium-doped fiber amplifier (EDFA) and a semiconductor optical amplifier (SOA), etc., and it can be an integrated amplifier or a discrete amplifier. Specifically, it is not limited here. In addition, the first site 10 and the second site 20 can be Figure 1 the optical amplifier sites shown, or other types of sites. For example, it can also be a reconfigurable optical add-drop multiplexer (ROADM) site. Specifically, it is not limited here.

[0045] Next, a method for determining the power compensation value of an optical signal provided by this application will be introduced:

[0046] Figure 2Schematic diagram of an embodiment of a method for determining a power compensation value of an optical signal in this application. In this example, the method for determining the power compensation value of the optical signal includes the following steps.

[0047] 201. Obtain a first optical signal and a second optical signal.

[0048] In this embodiment, the first optical signal is an optical signal obtained by up-converting or down-converting the second optical signal. The second optical signal can be a single-wavelength signal or a multi-wavelength signal. The second optical signal is distributed in at least one wavelength band. Different wavelength bands correspond to different wavelength signals, and each wavelength signal has its corresponding wavelength value. Each wavelength band includes the wavelength values of at least one wavelength signal. Based on the up-conversion or down-conversion of the second optical signal, the first optical signal can be a single-wavelength signal or a multi-wavelength signal. It should be understood that if the second optical signal is a single-wavelength signal, then the first optical signal is a multi-wavelength signal after up-converting the second optical signal. If the first optical signal is a single-wavelength signal, then the second optical signal is a multi-wavelength signal, and the first optical signal is obtained after down-converting the second optical signal. That is to say, the first optical signal and the second optical signal have some identical wavelength bands and some different wavelength bands. For convenience of description, in this application, the channel numbers of the wavelength signals are used to distinguish each wavelength signal (Ch1, Ch2, etc.). The wavelength value of each wavelength signal can be determined through the channel number of each wavelength signal. These wavelength signals can belong to either the C band or the L band, and specific details are not limited here. It should be noted that the first optical signal can be a full-wave signal (obtained after up-converting the second optical signal), or it can be a non-full-wave signal. The second optical signal can be a full-wave signal (the first optical signal is obtained after down-converting), or it can be a non-full-wave signal.

[0049] Figure 3 Schematic diagram of an embodiment where a multi-wavelength signal is distributed in multiple wavelength bands. For example, the second optical signal in this application is a full-wave signal, which includes a total of 100 wavelength signals from Ch1 to Ch100, and these 100 wavelength signals are distributed in 10 different wavelength bands. Every consecutive 10 wavelength signals are distributed in the same wavelength band. For example, wavelength signals Ch1 - Ch10 are distributed in wavelength band 1, wavelength signals Ch11 - Ch20 are distributed in wavelength band 2,..., Ch91 - Ch100 are distributed in wavelength band 10. The first optical signal in this application includes 6 wavelength signals, namely Ch1, Ch3, Ch5, Ch96, Ch98, and Ch100. Then wavelength signals Ch1, Ch3, and Ch5 are distributed in wavelength band 1, and wavelength signals Ch96, Ch98, and Ch100 are distributed in wavelength band 10.

[0050] It should be noted that this application does not limit the number of wavelength bands, which can be 10 as listed above, or 20, 30, etc. In practical applications, there can be various ways to divide the wavelength bands, such asFigure 3 The equal division method shown. It can also be a non-equal division method, that is, the number of wavelength signals corresponding to different wavebands can be different. In addition, the division granularity of the wavebands can also be different. For example, it can be as Figure 3 shown that each waveband corresponds to multiple wavelength signals. It can also be that each waveband uniquely corresponds to one wavelength signal. Specifically, it is not limited here. This application also does not limit the total number of available wavelengths, which can be, for example, as Figure 3 shown, 100 available wavelengths, or 120 or 200 available wavelengths, etc.

[0051] 202. Detect the first optical power of each waveband in the first optical signal and the second optical power of each waveband in the second optical signal.

[0052] In this embodiment, the optical power detection can specifically be implemented in a variety of ways, which will be introduced separately below.

[0053] The first, an implementation method combining a filter and a power detector (PD).

[0054] Figure 4 is a schematic diagram of an embodiment of the optical power detection in this application. As Figure 4 shown, it includes a plurality of filters 401 and a plurality of PDs (402), and they are in one-to-one correspondence. The optical signal of each waveband has a corresponding set of filters and PDs. Each filter can filter out the optical signal in the corresponding waveband. Furthermore, each PD detects the optical power of the corresponding waveband. Taking Figure 3 as an example, if the second optical signal is distributed in wavebands 1 to 10, then at least 10 sets of filters and PDs need to be set. When detecting the second optical power of each waveband in the second optical signal, these 10 PDs all need to work. When detecting the first optical power of each waveband in the first optical signal, only the first PD and the tenth PD are needed to detect the optical power of waveband 1 and waveband 10 respectively.

[0055] It should be noted that the filter can specifically adopt a discrete design as Figure 4 shown, or other forms of design, such as an integrated design or a cascaded filtering form. Specifically, it is not limited here.

[0056] In some possible implementation manners, a data acquisition unit 403 can also be set to collect the optical power detected by the PD. The data acquisition unit can specifically be implemented by a device with data acquisition functions such as an analog-to-digital converter (ADC).

[0057] The second, an implementation method of using a spectral detection unit for power detection.

[0058] Figure 5 This is a schematic diagram of another embodiment of optical power detection in this application. As Figure 5 shown, the spectral detection unit 501 can detect the spectral information of the optical signal. For example, it can detect the optical power of each wavelength signal. Furthermore, the data acquisition unit 502 collects the power detected by the spectral detection unit 501. It should be understood that the spectral detection unit 501 has the ability to detect signals within a specific wavelength range. Therefore, there is no need to configure a filter again, and the output of the spectral detection unit 501 is still the power of each band signal. The spectral detection unit can specifically be a device such as an optical spectrum analyzer (OSA) or an optical performance monitor (OPM), etc., which is not limited here.

[0059] 203. Determine the first optical power change amount of each band after the first optical signal is transmitted from the transmitting end to the receiving end according to the first optical power, and determine the second optical power change amount of each band after the second optical signal is transmitted from the transmitting end to the receiving end according to the second optical power.

[0060] Since the optical signal will be affected by the SRS effect during transmission in the optical fiber and cause power changes, before the optical signal is coupled into the optical fiber, it is necessary to pre-calculate the power change amount caused by the SRS effect for each band in the optical signal (including the first optical signal and the second optical signal). It should be understood that the power change amount of each band can also be referred to as a power transfer amount or a power net gain, etc., and this application does not limit its specific name.

[0061] Figure 6 This is a schematic diagram of an embodiment of power transfer between bands. As Figure 6 shown, the optical signal is divided into a total of 7 bands. Taking the power transfer of band 4 as an example for introduction. Affected by the SRS effect, the power of bands 1 to 3 will transfer to band 4, and the power of band 4 will also transfer to bands 5 to 7. That is to say, bands 1 to 3 will bring power gain to band 4, while bands 5 to 7 will bring power loss to band 4. Therefore, it is necessary to calculate the power change amount of band 4 relative to the other 6 bands respectively, and then sum them to obtain the total power change amount of band 4 affected by the SRS effect.

[0062] This embodiment provides a specific calculation method to calculate the power change amount of the band, which will be introduced in detail below.

[0063] First, it is necessary to obtain the first coefficient and the second coefficient. Among them, the first coefficient is a constant coefficient related to the transmission type of the signal. Specifically, the transmission type of the signal may include the optical fiber length, the optical fiber type, and the optical amplifier type, etc. It should be understood that usually after the network is built, parameters such as the optical fiber length, the optical fiber type, and the optical amplifier type can be determined, and these parameters can be pre-stored and refreshed regularly. Then, the corresponding first coefficient can be queried according to the data table pre-stored in the local memory. The data table can be as shown in Table 1 below:

[0064] Table 1

[0065]

[0066] The second coefficient is associated with the optical power transfer between every two wavebands. Specifically, the second coefficient can be expressed as Ti,j, which means the power transfer coefficient of waveband i relative to waveband j. Taking Figure 6 as an example, T4,1 represents the power transfer coefficient of waveband 4 relative to waveband 1. Since waveband 1 brings power gain to waveband 4, T4,1 is a positive value. T4,7 represents the power transfer coefficient of waveband 4 relative to waveband 7. Since waveband 7 brings power loss to waveband 4, T4,7 is a negative value. It should be understood that the second coefficient will also be pre-stored in the local memory in the form of a data table for convenient query during calculation. The data table can be as shown in Table 2 below:

[0067] Table 2

[0068]

[0069] Furthermore, according to the optical power of each waveband, the first coefficient, and the second coefficient in the optical signal (including the first optical signal and the second optical signal) calculated in step 202 above, calculate the power change amount of each waveband. Specifically, it can be calculated through the following formula. The formula is: where Si represents the total power change amount of waveband i, A represents the first coefficient, M represents the number of wavebands, Ti,j represents the second coefficient, and Pi represents the optical power of waveband i.

[0070] 204. Determine the first compensation value according to the first optical power change amount and the second optical power change amount, and determine the second compensation value according to the first optical power change amount and the second optical power change amount.

[0071] In this embodiment, the first compensation value is used to compensate the total power of the first optical signal, and the second compensation value is used to compensate the power spectrum slope of the first optical signal. The following is introduced through an example. Figure 7 It is a schematic diagram of an embodiment of the optical signal power change. As Figure 7As shown, L0 represents the power spectrum of the second optical signal. L1 represents the power spectrum of the first optical signal. L2 represents the power spectrum after power compensation for the first optical signal according to the first compensation value. It can be seen that after compensation according to the first compensation value, the total power of the first optical signal matches the total power of the second optical signal, but the power spectrum slopes of the two do not match, that is, the power fluctuation in the middle wavelength band is small, while the power fluctuation in the two side wavelength bands is still large. Therefore, it is also necessary to further compensate based on L2 according to the second compensation value to obtain the power spectrum shown in L3, so that the power spectrum slopes of the compensated first optical signal and the second optical signal also match, and the power spectrum of the first optical signal can be corrected more precisely. It should be understood that if the first optical signal is a single-wavelength signal, then the second compensation value can also be 0.

[0072] The calculation methods of the first compensation value and the second compensation value are introduced separately below.

[0073] The first compensation value can be calculated by the following first formula, which is introduced in detail below.

[0074] The first formula is: where C1 represents the first compensation value, i represents the serial number of the wavelength band, M represents the number of wavelength bands, Si1 represents the power change amount of the wavelength band i in the second optical signal, Si2 represents the power change amount of the wavelength band i in the first optical signal, and Xi represents the percentage of the optical power of the wavelength band i in the first optical signal in the total power of the first optical signal. It should be understood that Si1 and Si2 can be calculated by the steps described in step 203 above. Furthermore, by taking the difference between the power change amounts of each wavelength band of the upper and lower wavefronts and the power change amounts of each wavelength band after adding and removing the wave, multiplying by the power weighting value of each wavelength band, and finally summing the results of each wavelength band, the first compensation value can be obtained.

[0075] The second compensation value can be calculated by the following second formula, which is introduced in detail below.

[0076] The second formula is: C2 = (S1max - S1min) - (S2max - S2min). Where C2 represents the second compensation value, S1max represents the optical power change amount of the last wavelength band in the first optical signal, S1min represents the optical power change amount of the first wavelength band in the first optical signal, S2max represents the optical power change amount of the last wavelength band in the second optical signal, and S2min represents the optical power change amount of the first wavelength band in the second optical signal. It should be understood that (S1max - S1min) represents the power tilt amount of the first optical signal affected by the SRS effect, (S2max - S2min) represents the power tilt amount of the second optical signal affected by the SRS effect, and the subtraction of the two is the power tilt change amount caused by the up and down wave process.

[0077] It should be noted that the first waveband of the first optical signal refers to the waveband with the smallest wavelength in the first optical signal, and the last waveband of the first optical signal refers to the waveband with the largest wavelength in the first optical signal. The first waveband of the second optical signal refers to the waveband with the smallest wavelength in the second optical signal, and the last waveband of the second optical signal refers to the waveband with the largest wavelength in the second optical signal. For example, the second optical signal is distributed in wavebands 1 to 10, and the first waveband and the last waveband of the second optical signal are waveband 1 and waveband 10 respectively. The first optical signal after the second optical signal undergoes a lower wave is distributed in wavebands 2, 5, and 7, and the first waveband and the last waveband of the first optical signal are waveband 2 and waveband 7 respectively.

[0078] 205. Compensate the total power of the first optical signal according to the first compensation value, and compensate the power spectral slope of the first optical signal according to the second compensation value.

[0079] Figure 8 This is a schematic structural diagram of an optical amplifier in an embodiment of the present application. Specifically, the compensation for the total power and the power spectral slope can be achieved by adjusting the optical amplifier. The following will be further introduced in conjunction with Figure 8 for further introduction.

[0080] In the first aspect, if the first compensation value is positive, it is necessary to increase the currents of pump 1 and pump 2 inside the optical amplifier so that the first optical signal obtains a gain of the magnitude of the first compensation value after passing through the optical amplifier. If the first compensation value is negative, it is necessary to decrease the currents of pump 1 and pump 2 inside the optical amplifier so that the gain of the first optical signal after passing through the optical amplifier decreases by the magnitude corresponding to the first compensation value. For example, the total power of the first optical signal before power compensation is 18 dBm, and the first compensation value is 1 dB. Then the total power of the first optical signal after power compensation is 19 dBm.

[0081] In the second aspect, if the second compensation value is positive, it is necessary to increase the attenuation amount of the variable optical attenuator (VOA) between pump 1 and pump 2 so that the gain slope of the first optical signal after passing through the optical amplifier obtains an increase of the magnitude of the second compensation value. If the second compensation value is negative, it is necessary to decrease the attenuation amount of the VOA between pump 1 and pump 2 so that the gain slope of the first optical signal after passing through the optical amplifier decreases by the magnitude corresponding to the second compensation value.

[0082] In the embodiments of the present application, the first optical signal is an optical signal obtained by wavelength multiplexing or demultiplexing based on the second optical signal. The signal transmitter needs to detect the first optical power of each wavelength band in the first optical signal and the second optical power of each wavelength band in the second optical signal. Subsequently, the change in the first optical power caused by the SRS effect for each wavelength band after the first optical signal is transmitted from the transmitter to the receiver can be calculated based on the first optical power, and the change in the second optical power caused by the SRS effect for each wavelength band after the second optical signal is transmitted from the transmitter to the receiver can be calculated based on the second optical power. Next, a first compensation value and a second compensation value are determined based on the change in the first optical power and the change in the second optical power. Furthermore, before transmitting the first optical signal, the total power of the first optical signal can be compensated based on the first compensation value, so that the power change caused by the SRS effect during the transmission of the first optical signal in the optical fiber does not exceed the tolerance of the system, improving the stability of signal transmission. Additionally, the power spectral slope of the first optical signal can also be compensated based on the second compensation value, such that the power spectral slopes of the first optical signal and the second optical signal received by the signal receiver match, further improving the stability of signal transmission.

[0083] The method for determining the power compensation value of an optical signal in the embodiments of the present application is introduced above. Next, the power calculation device in the embodiments of the present application is described:

[0084] Figure 9 It is a schematic structural diagram of a power calculation device. The power calculation device includes a processor 901, a memory 902, and an optical detection module 903. The processor 901, the memory 902, and the optical detection module 903 are interconnected by lines. Among them, the memory 902 is used to store program instructions and data. It should be noted that the power calculation device can be a power calculation device that implements the method for determining the power compensation value of an optical signal in the above Figure 2 illustrated embodiments.

[0085] In a possible implementation manner, the memory 902 stores program instructions and data (such as the first coefficient and the second coefficient described in step 203 above) that support the Figure 2 illustrated steps, and the processor 901 and the optical detection module 903 are used to execute the Figure 2 illustrated method steps. Specifically, the optical detection module 903 is used to execute the Figure 2 illustrated steps 201 and 202. The processor 901 is used to execute the Figure 2 illustrated steps 203 - 205.

[0086] It should be understood that the optical detection module 903 can be divided into a filter 401, a PD (402), and a data acquisition unit 403 as Figure 4 illustrated. Alternatively, the optical detection module 903 can also be asFigure 5 It is divided into a spectrum detection unit 501 and a data acquisition unit 502 as shown.

[0087] Figure 10 This is a schematic structural diagram of an optical transmission system in an embodiment of the present application. The optical transmission system includes a first site 1001 and a second site 1002. Among them, the optical signal output by the first site 1001 is transmitted to the second site 1002 through an optical fiber. Specifically, the first site 1001 is used to execute Figure 2 any of the method steps in the embodiment shown. Before the optical signal output by the first site 1001 is coupled into the optical fiber, the first compensation value and the second compensation value can be pre-calculated respectively, which are used to compensate the change amount of the total power and the change amount of the power spectrum slope of the optical signal. It should be understood that the first site can be an optical amplifier site or a ROADM site, etc., and specific limitations are not made here.

[0088] Those of ordinary skill in the art can understand that all or part of the steps of implementing the above embodiments can be completed by hardware, or can be completed by instructing relevant hardware through a program. The program can be stored in a computer-readable storage medium. The above-mentioned storage medium can be a read-only memory, a random access memory, etc. Specifically, for example: the above-mentioned processing unit or processor can be a central processing unit, a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. Whether the above functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but this implementation should not be considered to exceed the scope of the present application.

[0089] When implemented using software, the method steps described in the above embodiments may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (such as a floppy disk, hard disk, magnetic tape), an optical medium (such as a DVD), or a semiconductor medium (such as a solid state disk (SSD)).

[0090] Finally, it should be noted that the above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application, and all of them should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for determining a power compensation value of an optical signal, characterized in that, comprising: obtaining a first optical signal and a second optical signal, where the first optical signal is an optical signal obtained by up-converting or down-converting the second optical signal, the second optical signal includes at least one wavelength signal, at least one wavelength signal of the second optical signal is distributed in at least one wavelength band, the first optical signal includes at least one wavelength signal, and at least one wavelength signal of the first optical signal is distributed in at least one wavelength band, wherein, one wavelength signal of the first optical signal is distributed in any one wavelength band corresponding to the first optical signal, and one wavelength signal of the second optical signal is distributed in any one wavelength band corresponding to the second optical signal; detecting a first optical power of each wavelength band in the first optical signal and a second optical power of each wavelength band in the second optical signal; determining, according to the first optical power, a first optical power change amount of each wavelength band corresponding to the first optical signal after the first optical signal is transmitted from a transmitting end to a receiving end, and determining, according to the second optical power, a second optical power change amount of each wavelength band corresponding to the second optical signal after the second optical signal is transmitted from the transmitting end to the receiving end; determining a first compensation value according to the first optical power change amount and the second optical power change amount, where the first compensation value is used to compensate the total power of the first optical signal; determining a second compensation value according to the first optical power change amount and the second optical power change amount, where the second compensation value is used to compensate the power spectral slope of the first optical signal.

2. The method according to claim 1, characterized in that, the method further comprises: obtaining a first coefficient and a second coefficient, where the first coefficient is associated with the transmission type of the signal, and the second coefficient is associated with the optical power transfer between every two wavelength bands; determining, according to the first optical power, the first optical power change amount of each wavelength band after the first optical signal is transmitted from the transmitting end to the receiving end includes: calculating the first optical power change amount according to the first optical power, the first coefficient, and the second coefficient; determining, according to the second optical power, the second optical power change amount of each wavelength band after the second optical signal is transmitted from the transmitting end to the receiving end includes: calculating the second optical power change amount according to the second optical power, the first coefficient, and the second coefficient.

3. The method according to claim 1 or 2, characterized in that, the method further comprises: obtaining a ratio of the optical power of each wavelength band in the first optical signal to the total power of the first optical signal; determining the first compensation value according to the first optical power change amount and the second optical power change amount includes: substituting the first optical power change amount, the second optical power change amount, and the ratio into a first formula to calculate the first compensation value; The first formula includes: wherein, C1 represents the first compensation value, i represents the serial number of the wavelength band, M represents the number of wavelength bands, Si1 represents the second optical power change amount of the wavelength band i in the second optical signal, Si2 represents the first optical power change amount of the wavelength band i in the first optical signal, and Xi represents the ratio.

4. The method according to claim 1 or 2, determining a second compensation value according to the first optical power change amount and the second optical power change amount comprising: substituting the first optical power change amount of the first waveband at the head of the first optical signal, the first optical power change amount of the last waveband of the first optical signal, the second optical power change amount of the first waveband at the head of the second optical signal, and the second optical power change amount of the last waveband of the second optical signal into a second formula to calculate the second compensation value; The second formula includes: C2 = (S1max - S1min) - (S2max - S2min); wherein, the C2 represents the second compensation value, the S1max represents the first optical power change amount of the last waveband of the first optical signal, the S1min represents the first optical power change amount of the first waveband at the head of the first optical signal, the S2max represents the second optical power change amount of the last waveband of the second optical signal, and the S2min represents the second optical power change amount of the first waveband at the head of the second optical signal.

5. The method according to claim 1 or 2, characterized in that, the method further includes: compensating the total power of the first optical signal according to the first compensation value; compensating the power spectral slope of the first optical signal according to the second compensation value.

6. The method according to claim 5, characterized in that, compensating the total power of the first optical signal according to the first compensation value includes: adjusting the pump current in the optical amplifier according to the first compensation value to adjust the output power of the first optical signal after passing through the optical amplifier.

7. The method according to claim 5, characterized in that, compensating the power spectral slope of the first optical signal according to the second compensation value includes: adjusting the attenuation amount of the variable optical attenuator VOA in the optical amplifier according to the second compensation value to adjust the power spectral slope of the first optical signal after passing through the optical amplifier.

8. The method according to claim 1 or 2, characterized in that, detecting the first optical power of each waveband in the first optical signal includes: dividing the first optical signal into optical signals of multiple wavebands through a filter; detecting the first optical power of each waveband in the first optical signal through a power detector; detecting the second optical power of each waveband in the second optical signal includes: dividing the second optical signal into optical signals of multiple wavebands through a filter; detecting the second optical power of each waveband in the second optical signal through a power detector.

9. The method according to claim 1 or 2, characterized in that, detecting the first optical power of each waveband in the first optical signal includes: detecting the first optical power of each wavelength in the first optical signal through an optical spectrum analyzer OSA or an optical performance monitor OPM; detecting the second optical power of each waveband in the second optical signal includes: detecting the second optical power of each wavelength in the second optical signal through an optical spectrum analyzer OSA or an optical performance monitor OPM.

10. A power calculation device, characterized in that, comprising: A processor, a memory, and an optical detection module, where the processor, the memory, and the optical detection module are interconnected by lines; The optical detection module is configured to: Obtain a first optical signal and a second optical signal, where the first optical signal is an optical signal obtained by up-converting or down-converting the second optical signal, the second optical signal includes at least one wavelength signal, at least one wavelength signal of the second optical signal is distributed in at least one waveband, the first optical signal includes at least one wavelength signal, and at least one wavelength signal of the first optical signal is distributed in at least one waveband. Among them, one wavelength signal of the first optical signal is distributed in any one waveband corresponding to the first optical signal, and one wavelength signal of the second optical signal is distributed in any one waveband corresponding to the second optical signal; Detect the first optical power of each waveband in the first optical signal and the second optical power of each waveband in the second optical signal; The processor is configured to: Determine the change amount of the first optical power of each waveband corresponding to the first optical signal after the first optical signal is transmitted from the sending end to the receiving end according to the first optical power, and determine the change amount of the second optical power of each waveband corresponding to the second optical signal after the second optical signal is transmitted from the sending end to the receiving end according to the second optical power; Determine a first compensation value according to the change amount of the first optical power and the change amount of the second optical power, where the first compensation value is used to compensate the total power of the first optical signal; Determine a second compensation value according to the change amount of the first optical power and the change amount of the second optical power, where the second compensation value is used to compensate the power spectrum slope of the first optical signal.

11. The power calculation device according to claim 10, wherein, The processor is further configured to: Obtain a first coefficient and a second coefficient, where the first coefficient is associated with the transmission type of the signal, and the second coefficient is associated with the optical power transfer between every two wavebands; Specifically, the processor is configured to: Calculate the change amount of the first optical power according to the first optical power, the first coefficient, and the second coefficient; Calculate the change amount of the second optical power according to the second optical power, the first coefficient, and the second coefficient.

12. The power calculation device according to claim 10 or 11, wherein, The processor is further configured to: Obtain the ratio of the optical power of each waveband in the first optical signal to the total power of the first optical signal; Specifically, the processor is configured to: Substitute the change amount of the first optical power, the change amount of the second optical power, and the ratio into a first formula to calculate the first compensation value; The first formula includes: where C1 represents the first compensation value, i represents the serial number of the waveband, M represents the number of wavebands, Si1 represents the change amount of the second optical power of waveband i in the second optical signal, Si2 represents the change amount of the first optical power of waveband i in the first optical signal, and Xi represents the ratio.

13. The power calculation device according to claim 10 or 11, wherein, Specifically, the processor is configured to: Substitute the first optical power variation of the first waveband in the first optical signal, the first optical power variation of the last waveband in the first optical signal, the second optical power variation of the first waveband in the second optical signal, and the second optical power variation of the last waveband in the second optical signal into the second formula to calculate the second compensation value; The second formula includes: C2 = (S1max - S1min) - (S2max - S2min); Wherein, C2 represents the second compensation value, S1max represents the first optical power variation of the last waveband in the first optical signal, S1min represents the first optical power variation of the first waveband in the first optical signal, S2max represents the second optical power variation of the last waveband in the second optical signal, and S2min represents the second optical power variation of the first waveband in the second optical signal.

14. The power calculation device according to claim 10 or 11, Characterized in that, The processor is further configured to: Compensate the total power of the first optical signal according to the first compensation value; Compensate the power spectral slope of the first optical signal according to the second compensation value.

15. The power calculation device according to claim 14, Characterized in that, The processor is specifically configured to: Adjust the pump current in the optical amplifier according to the first compensation value to adjust the output power of the first optical signal after passing through the optical amplifier.

16. The power calculation device according to claim 14, Characterized in that, The processor is specifically configured to: Adjust the attenuation amount of the variable optical attenuator VOA in the optical amplifier according to the second compensation value to adjust the power spectral slope of the first optical signal after passing through the optical amplifier.

17. The power calculation device according to claim 10 or 11, Characterized in that, The optical detection module includes a filter and a power detector; The filter is used for: Dividing the first optical signal into optical signals of multiple wavebands; Dividing the second optical signal into optical signals of multiple wavebands; The power detector is used for: Detecting the first optical power of each waveband in the first optical signal; Detecting the second optical power of each waveband in the second optical signal.

18. The power calculation device according to claim 10 or 11, Characterized in that, The optical detection module includes an optical spectrum analyzer OSA or an optical performance monitor OPM; The OSA or the OPM is used for: Detecting the first optical power of each wavelength in the first optical signal; Detecting the second optical power of each wavelength in the second optical signal.

19. An optical transmission system, Characterized in that, Including: A first site and a second site, the first site is used to execute the method for determining the power compensation value of the optical signal according to any one of claims 1 to 9, and the second site is used to receive the optical signal output by the first site.

20. The optical transmission system according to claim 19, Characterized in that, The first site includes an optical amplifier site or a reconfigurable optical add-drop multiplexer ROADM site.

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