CN113973238B

CN113973238B - Frequency offset processing method and frequency offset processing device of wavelength selective switch WSS

Info

Publication number: CN113973238B
Application number: CN202010714525.7A
Authority: CN
Inventors: 秦华强; 潘超; 贾伟
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-07-23
Filing date: 2020-07-23
Publication date: 2023-03-24
Anticipated expiration: 2040-07-23
Also published as: CN113973238A; WO2022016982A1

Abstract

The present invention relates to the field of optical communications, and in particular, to a frequency offset processing method and a frequency offset processing apparatus for a wavelength selective switch WSS. The frequency offset processing method comprises the following steps: an amount of frequency offset drift for each of one or more channels of the WSS is determined. Here, the frequency offset drift amount of any one of the one or more channels is used to indicate a degree of difference between the frequency offset of the any one channel at a first time and the frequency offset of the any one channel at a second time. And performing frequency offset compensation on each channel according to the frequency offset drift amount of each channel. By adopting the frequency offset processing method provided by the application, the frequency offset compensation precision of the WSS channel can be improved, and the stable performance of the WSS is ensured.

Description

Frequency offset processing method and frequency offset processing device of wavelength selective switch WSS

Technical Field

The present application relates to the field of optical communications, and in particular, to a frequency offset processing method and a frequency offset processing apparatus.

Background

With the continuous development of optical communication technology, as a wavelength scheduling center of an optical network, the use of a Wavelength Selective Switch (WSS) becomes more and more common. Since the WSS is a necessary device in the optical signal transmission process, the performance of the WSS directly affects the transmission quality of the optical signal, and therefore, the performance of the WSS is also receiving more attention.

The main function of the WSS is to implement wavelength selection of an optical signal, and a filtering spectrum frequency offset (hereinafter referred to as frequency offset) of the WSS is regarded as an important performance index of the WSS. In the using process, along with the aging of internal devices of the WSS or the change of external environment (such as the change of environmental temperature, air pressure and the like), the central wavelength of a filter spectrum of the WSS also changes, so that the frequency offset of the WSS also changes along with the change. Because the change of the frequency offset of the WSS may cause additional transmission cost, in the prior art, the change of the frequency offset of the WSS is detected first, and then the frequency offset of the WSS is compensated according to the detected change to maintain the stability of the frequency offset of the WSS, thereby overcoming the additional transmission cost. However, in the prior art, the detection error of the variation of the frequency offset of the WSS is large, so that the frequency offset compensation of the WSS cannot be effectively and accurately realized, which makes the performance of the WSS not guaranteed.

Disclosure of Invention

In order to solve the above problems, the present application provides a method and an apparatus for processing frequency offset of a wavelength selective switch WSS, which can improve the precision of frequency offset compensation of the WSS, thereby ensuring stable performance of the WSS.

In a first aspect, an embodiment of the present application provides a method for processing frequency offset of a WSS. An amount of frequency offset drift for each of one or more channels of the WSS is first determined. Here, the frequency offset drift amount of any one of the one or more channels is used to indicate a difference degree between the frequency offset of the any one channel at the first time and the frequency offset of the any one channel at the second time. And then performing frequency offset compensation corresponding to each channel according to the frequency offset drift amount of each channel.

In the embodiment of the application, the frequency offset drift amount of each channel is detected, and then frequency offset compensation is performed on each channel based on the frequency offset drift amount of each channel. Because the frequency offset of each channel is compensated based on the frequency offset drift amount of each channel, and the frequency offset drift amount of each channel eliminates detection errors caused by factory frequency offset, the WSS frequency offset compensation is reasonable and effective. Therefore, after frequency offset compensation, the frequency offset of each channel of the WSS can reach or approach the frequency offset of the WSS at the first moment, so that the change of the frequency offset brought to the WSS by factors such as device aging is avoided, the performance of the WSS can be maintained at the level of the first moment, and the stability of the performance of the WSS is ensured.

With reference to the first aspect, in a first possible implementation manner, one or more target channels may be determined from one or more channels of the WSS. Then, an amount of frequency offset drift for each of the one or more target channels is determined. And determining the frequency offset drift amount of each channel in one or more channels of the WSS according to the frequency offset drift amount of each target channel. In the implementation mode, one or more target channels are determined, then the frequency offset drift amount of each target channel, which does not include the factory frequency offset, is obtained through detection, and then the frequency offset drift amount of each channel in the one or more channels is determined based on the frequency offset drift amount of each target channel, so that errors caused by the irregularity of the factory frequency offset to the frequency offset drift amount can be avoided, and the detection accuracy of the frequency offset drift amount of each channel is improved.

With reference to the first possible implementation manner of the first aspect, in a second possible implementation manner, the WSS includes a switching engine, and the switching engine includes a plurality of switching units. The target filtered spectrum of the first switching unit may be acquired first. Here, the first switching unit is a switching unit corresponding to the first target channel on the switching engine. And then determining the frequency offset drift amount of a first target channel according to the central wavelength of the target filtering spectrum and the wavelength corresponding to the first switching unit at the first moment. Here, the first target channel is any one of the one or more target channels. In the implementation manner, the first switching unit is subjected to wavelength scanning to obtain a target filter spectrum of the first switching unit, and then the frequency offset drift amount of the first target channel is directly determined according to the center wavelength of the target filter spectrum and the wavelength corresponding to the first switching unit at the first moment.

With reference to the second possible implementation manner of the first aspect, in a third possible implementation manner, the optical signal generator may be controlled to perform wavelength scanning on the first switching unit by using at least one optical signal with a first preset wavelength. And respectively acquiring first input power and first output power of the WSS under the optical signal with each first preset wavelength in the at least one first preset wavelength. And determining a target filter spectrum of the first switching unit according to the first input power and the first output power of the WSS under each optical signal with the first preset wavelength. Here, the target filtered spectrum includes a first insertion loss value of the first switching unit at each of the first preset wavelengths, and the first insertion loss value of the first switching unit at any one of the first preset wavelengths is a difference between a first output power and a first input power of the WSS at the optical signal at any one of the first preset wavelengths.

With reference to the second or third possible implementation manner of the first aspect, in a fourth possible implementation manner, the center wavelength of the target filter spectrum is a first preset wavelength at which an absolute value of a first insertion loss value in each first preset wavelength is smallest.

With reference to the first possible implementation manner of the first aspect, in a fifth possible implementation manner, the WSS includes a switching engine. When the optical signal with the second preset wavelength passes through the first target channel, the target position of the light spot generated on the switching engine by the optical signal with the second preset wavelength may be obtained first. And determining the frequency offset drift amount of the first target channel according to the wavelength of the target position at the first moment and the second preset wavelength. Here, the first target channel is any one of the one or more target channels. In the implementation manner, only the optical signal with the fixed second preset wavelength is used as the input optical signal of the WSS to obtain the second insertion loss value of each second switching unit, and the optical signal generator is not required to frequently adjust the output wavelength, thereby simplifying the control flow of the processor. Therefore, on one hand, the performance requirement of the optical signal generator can be lowered, the implementation cost of the frequency offset processing device can be lowered, on the other hand, the implementation process of the frequency offset processing method can be simplified, and the execution efficiency of the frequency offset processing method is improved.

With reference to the fifth possible implementation manner of the first aspect, in a sixth possible implementation manner, the switching engine includes multiple switching units. A second insertion loss value of each of the at least two second switching units corresponding to the first target channel on the switching engine at the second preset wavelength may be determined first. And determining the target position of a light spot generated on the switching engine by the optical signal under the second preset wavelength according to a second insertion loss value of each second switching unit under the second preset wavelength and a preset filter spectrum of each second switching unit at the first moment. Here, the preset filter spectrum of any second switching unit of the at least two switching units indicates preset insertion loss values corresponding to a plurality of preset positions of the any second switching unit in the dispersion direction of the switching engine.

With reference to the sixth implementation manner of the first aspect, in a seventh possible implementation manner, the second insertion loss value of any one of the second switching units at the second preset wavelength is a difference between a second input power and a second output power of the any one of the second switching units when the optical signal at the second preset wavelength passes through the first target channel.

With reference to the sixth or seventh possible implementation manner of the first aspect, in an eighth possible implementation manner, the preset insertion loss value set corresponding to each preset position in the plurality of preset positions may be determined according to a preset filter spectrum of each second switching unit at the first time. Here, the preset insertion loss value set corresponding to any preset position includes a preset insertion loss value corresponding to each second switching unit at any preset position. And determining a target position of a light spot generated on the switching engine by the optical signal under the second preset wavelength from the plurality of preset positions according to a second insertion loss value of each second switching unit under the second preset wavelength and a preset insertion loss value set corresponding to each preset position. Here, by comparing the plurality of second insertion loss values detected in real time with the plurality of preset insertion loss values at each preset position, the position of the light spot generated on the switching engine by the optical signal at the second preset wavelength can be simply and accurately determined from the plurality of preset positions.

With reference to the eighth possible implementation manner of the first aspect, in a ninth possible implementation manner, the first relative insertion loss value group corresponding to each preset position may be determined according to the preset insertion loss value set corresponding to each preset position. Here, the first relative insertion loss value group corresponding to any one preset position includes a comparison result of the preset insertion loss values of any two second exchange units at the any one preset position. And determining a second relative insertion loss value set according to a second insertion loss value of each second exchange unit under the optical signal with the second preset wavelength, wherein the second relative insertion loss value set comprises a comparison result of the second insertion loss values of any two second exchange units. Then, a target relative insertion loss value group matching the second relative insertion loss value group is determined from the first relative insertion loss value group corresponding to each preset position, and a preset position corresponding to the target relative insertion loss value group is determined as a target position of a light spot generated on the switching engine by the optical signal at the second preset wavelength. In this implementation manner, the preset insertion loss values in each preset insertion loss value set are compared with each other to obtain a first relative insertion loss value set corresponding to each preset position, and then a target relative insertion loss value set matched with the second relative insertion loss value set is determined from the plurality of first relative insertion loss value sets, so that the plurality of preset insertion loss values included in the determined target relative insertion loss value set are closest to the second insertion loss value of each second exchange unit, and the accuracy of the subsequently determined frequency offset drift amount of the first target channel can be further ensured.

With reference to the first possible implementation manner to the ninth possible implementation manner of the first aspect, in a tenth possible implementation manner, the target channel is a traffic channel through which no traffic optical signal of the WSS passes, and/or a non-traffic channel of the WSS other than the traffic channel. In the implementation manner, the service channel and/or the non-service channel distributed in a relatively dispersed area on the switching engine is/are selected as the target channel, so that the frequency offset drift amount of each channel in the one or more channels can be obtained by accurately fitting the measured frequency offset drift amount of each target channel, and the detection precision of the frequency offset drift amount of each channel is improved.

In a second aspect, an embodiment of the present application provides a frequency offset processing apparatus for a WSS. The apparatus includes a processor. The processor is configured to determine an amount of frequency offset drift for each of one or more channels of the WSS. Here, the frequency offset drift amount of any one of the one or more channels is used to indicate a degree of offset between the frequency offset of the any one channel at a first time and the frequency offset of the any one channel at a second time. The processor is further configured to perform frequency offset compensation on each channel according to the frequency offset drift amount of each channel.

With reference to the second aspect, in a first possible implementation manner, the processor is further configured to determine one or more target channels from the one or more channels of the WSS, and determine a frequency offset drift amount of each of the one or more target channels. And determining the frequency offset drift amount of each channel in one or more channels of the WSS according to the frequency offset drift amount of each target channel.

With reference to the first possible implementation manner of the second aspect, in a second possible implementation manner, the WSS includes a switching engine, and the switching engine includes a plurality of switching units. The processor is used for obtaining the target filtering spectrum of the first exchange unit. The processor is further configured to determine a frequency offset drift amount of a first target channel according to the center wavelength of the target filter spectrum and the wavelength corresponding to the first switching unit at the first time. Here, the first target channel is any one of the one or more target channels.

With reference to the second possible implementation manner of the second aspect, in a third possible implementation manner, the frequency offset processing apparatus further includes an optical signal generator and a photodetector. The optical signal generator is used for performing wavelength scanning on the first switching unit by using at least one optical signal with a first preset wavelength. The photodetector is configured to obtain a first input power and a first output power of the WSS under an optical signal of each of the at least one first preset wavelength. The processor is further configured to determine a target filter spectrum of the first switching unit according to a first input power and a first output power of the WSS under each optical signal with a first preset wavelength. Here, the target filtered spectrum includes a corresponding first insertion loss value of the first switching unit at each first preset wavelength, and the first insertion loss value of the first switching unit at any first preset wavelength is a difference value between a first output power and a first input power of the WSS at an optical signal at any first preset wavelength.

With reference to the second or third possible implementation manner of the second aspect, in a fourth possible implementation manner, the center wavelength of the target filter spectrum is a first preset wavelength at which an absolute value of a first insertion loss value in each first preset wavelength is smallest.

With reference to the first possible implementation manner of the second aspect, in a fifth possible implementation manner, the processor is further configured to obtain a target position of a light spot, generated by the WSS switching engine, of an optical signal at a second preset wavelength when the optical signal at the second preset wavelength passes through the first target channel. And determining the frequency offset drift amount of the first target channel according to the wavelength of the target position at the first moment and the second preset wavelength. Here, the first target channel is any one of the one or more target channels.

With reference to the fifth possible implementation manner of the second aspect, in a sixth possible implementation manner, the switching engine includes a plurality of switching units, and the processor is further configured to determine second insertion loss values of each of at least two second switching units, corresponding to the first target channel on the switching engine, at the second preset wavelength respectively. And determining the target position of the light spot generated by the optical signal under the second preset wavelength in the WSS switching engine according to the second insertion loss value of each second switching unit under the second preset wavelength and the preset filter spectrum of each second switching unit at the first moment. Here, the preset filter spectrum of any second switching unit of the at least two switching units includes preset insertion loss values corresponding to a plurality of preset positions of the any second switching unit in the dispersion direction of the switching engine.

With reference to the sixth possible implementation manner of the second aspect, in a seventh possible implementation manner, the frequency offset processing apparatus further includes a photodetector. The photodetector is configured to obtain a second input power and a second output power of any one of the second switching units when the optical signal with the second preset wavelength passes through the first target channel. The processor is configured to determine a difference between a second input power and a second output power of the second switching unit when the optical signal with the second preset wavelength passes through the first target channel, as a second insertion loss value of the second switching unit at the second preset wavelength.

With reference to the sixth or seventh possible implementation manner of the second aspect, in an eighth possible implementation manner, the processor is further configured to determine, according to a preset filter spectrum of each second switching unit at the first time, a preset insertion loss value set corresponding to each preset position in the plurality of preset positions. Here, the preset insertion loss value set corresponding to any preset position includes a preset insertion loss value corresponding to each second switching unit at any preset position. And determining a target position of a light spot generated on the switching engine by the optical signal under the second preset wavelength from the plurality of preset positions according to a second insertion loss value of each second switching unit under the second preset wavelength and a preset insertion loss value set corresponding to each preset position.

With reference to the eighth possible implementation manner of the second aspect, in a ninth possible implementation manner, the processor is further configured to determine the first relative insertion loss value set corresponding to each preset position according to the preset insertion loss value set corresponding to each preset position. Here, the first relative insertion loss value group corresponding to any one preset position includes a comparison result of the preset insertion loss values of any two second exchange units at the any one preset position. And determining a second relative insertion loss value set according to a second insertion loss value of each second exchange unit under the optical signal with the second preset wavelength. Here, the second relative insertion value group includes a result of comparing the second insertion values of any two second switching units. And determining a target relative insertion loss group matched with the second relative insertion loss group from the first relative insertion loss group corresponding to each preset position, and determining a preset position corresponding to the target relative insertion loss group as a target position of a light spot generated on the exchange engine by the optical signal under the second preset wavelength.

With reference to the second aspect to the ninth implementation manner of the second aspect, in a tenth possible implementation manner, the target channel is a traffic channel through which no traffic optical signal of the WSS passes, and/or a non-traffic channel of the WSS other than the traffic channel.

In a third aspect, an embodiment of the present application provides a frequency offset processing apparatus. The apparatus includes a processing unit. The processing unit is configured to determine a frequency offset drift amount of each of one or more channels of the WSS. Here, the frequency offset drift amount of any one of the one or more channels is used to indicate a degree of difference between the frequency offset of the any one channel at a first time and the frequency offset of the any one channel at a second time. The processing unit is further configured to perform frequency offset compensation on each channel according to the frequency offset drift amount of each channel.

With reference to the third aspect, in a first possible implementation manner, the processing unit is further configured to determine one or more target channels from the one or more channels of the WSS, and determine a frequency offset drift amount of each target channel of the one or more target channels. And determining the frequency offset drift amount of each channel in one or more channels of the WSS according to the frequency offset drift amount of each target channel.

With reference to the first possible implementation manner of the third aspect, in a second possible implementation manner, the WSS includes a switching engine, and the switching engine includes a plurality of switching units. The processing unit is used for acquiring a target filtering spectrum of the first exchange unit. The processing unit is further configured to determine a frequency offset drift amount of a first target channel according to the center wavelength of the target filter spectrum and the wavelength corresponding to the first switching unit at the first time. Here, the first target channel is any one of the one or more target channels.

With reference to the second possible implementation manner of the third aspect, in a third possible implementation manner, the frequency offset processing apparatus further includes an optical signal generating unit and an optical detection unit. The optical signal generating unit is used for performing wavelength scanning on the first switching unit by using at least one optical signal with a first preset wavelength. The photoelectric detection unit is configured to acquire a first input power and a first output power of the WSS under an optical signal of each first preset wavelength in the at least one first preset wavelength. The processing unit is further configured to determine a target filter spectrum of the first switching unit according to the first input power and the first output power of the WSS under each optical signal with the first preset wavelength. Here, the target filtered spectrum includes a corresponding first insertion loss value of the first switching unit at each first preset wavelength, and the first insertion loss value of the first switching unit at any first preset wavelength is a difference value between a first output power and a first input power of the WSS at an optical signal at any first preset wavelength.

With reference to the second or third possible implementation manner of the third aspect, in a fourth possible implementation manner, the center wavelength of the target filter spectrum is a first preset wavelength at which an absolute value of a first insertion loss value in each first preset wavelength is smallest.

With reference to the first possible implementation manner of the third aspect, in a fifth possible implementation manner, the processing unit is further configured to obtain a target position of a light spot, generated by the WSS switching engine, of an optical signal at a second preset wavelength when the optical signal at the second preset wavelength passes through the first target channel. And determining the frequency offset drift amount of the first target channel according to the wavelength of the target position at the first moment and the second preset wavelength. Here, the first target channel is any one of the one or more target channels.

With reference to the fifth possible implementation manner of the third aspect, in a sixth possible implementation manner, the switching engine includes a plurality of switching units, and the processing unit is further configured to determine second insertion loss values of each of at least two second switching units, where the corresponding second switching unit is located on the switching engine, of the first target channel, respectively. And determining the target position of the light spot generated by the optical signal under the second preset wavelength in the WSS switching engine according to the second insertion loss value of each second switching unit under the second preset wavelength and the preset filter spectrum of each second switching unit at the first moment. Here, the preset filter spectrum of any second switching unit in the at least two switching units includes preset insertion loss values corresponding to a plurality of preset positions of the any second switching unit in the dispersion direction of the switching engine.

With reference to the sixth possible implementation manner of the third aspect, in a seventh possible implementation manner, the frequency offset processing apparatus further includes a photodetecting unit. The photoelectric detection unit is configured to obtain a second input power and a second output power of any one of the second switching units when the optical signal with the second preset wavelength passes through the first target channel. The processing unit is configured to determine a difference between a second input power and a second output power of the second switching unit when the optical signal with the second preset wavelength passes through the first target channel, as a second insertion loss value of the second switching unit at the second preset wavelength.

With reference to the sixth or seventh possible implementation manner of the third aspect, in an eighth possible implementation manner, the processing unit is further configured to determine, according to a preset filter spectrum of each second switching unit at the first time, a preset insertion loss value set corresponding to each preset position in the plurality of preset positions. Here, the preset insertion loss value set corresponding to any preset position includes a preset insertion loss value corresponding to each second switching unit at any preset position. And determining a target position of a light spot generated on the switching engine by the optical signal under the second preset wavelength from the plurality of preset positions according to a second insertion loss value of each second switching unit under the second preset wavelength and a preset insertion loss value set corresponding to each preset position.

With reference to the eighth possible implementation manner of the third aspect, in a ninth possible implementation manner, the processing unit is further configured to determine, according to the preset insertion loss value set corresponding to each preset position, a first relative insertion loss value set corresponding to each preset position. Here, the first relative insertion loss value group corresponding to any one preset position includes a comparison result of the preset insertion loss values of any two second exchange units at the any one preset position. And determining a second relative insertion loss value set according to a second insertion loss value of each second exchange unit under the optical signal with the second preset wavelength. Here, the second relative insertion value group includes a result of comparing the second insertion values of any two second switching units. And determining a target relative insertion loss group matched with the second relative insertion loss group from the first relative insertion loss group corresponding to each preset position, and determining a preset position corresponding to the target relative insertion loss group as a target position of a light spot generated on the exchange engine by the optical signal under the second preset wavelength.

With reference to the third aspect to the ninth implementation manner of the third aspect, in a tenth possible implementation manner, the target channel is a traffic channel through which no traffic optical signal of the WSS passes, and/or a non-traffic channel of the WSS except for the traffic channel.

In a fourth aspect, an embodiment of the present application provides a frequency offset processing system. The frequency offset processing system includes the frequency offset processing apparatus according to the second aspect or the third aspect, and a WSS for passing through the optical signal at each of the first preset wavelengths or the optical signal at the second preset wavelength.

In a fifth aspect, the present application provides a computer-readable storage medium having instructions stored therein, the instructions executable by one or more processors on a processing circuit. When run on a computer, causes the computer to perform the frequency offset processing method of the first aspect described above.

In a sixth aspect, the present application provides a computer program product containing instructions which, when run on a computer, cause the computer to perform the frequency offset processing method of the first aspect.

In a seventh aspect, an embodiment of the present application provides a chip or a chip system, including an input/output interface and a processing circuit, where the input/output interface is used for exchanging information or data, and the processing circuit is used for executing an instruction, so that an apparatus on which the chip or the chip system is mounted performs the frequency offset processing method provided in the first aspect.

In an eighth aspect, the present application provides a chip system, where the chip system includes a processor, and is used to support an apparatus that mounts the chip system to implement the frequency offset processing method provided in the first aspect, for example, to generate or process data and/or information involved in the method. In one possible design, the system-on-chip further includes a memory for storing program instructions and data necessary for the data transmission device. The chip system may be formed by a chip, and may also include a chip and other discrete devices.

Drawings

FIG. 1 is a schematic diagram of an internal structure of a WSS provided in an embodiment of the present application;

FIG. 2 is a block diagram of an exemplary embodiment of a switching engine;

fig. 3 is a schematic diagram illustrating a communication area division of a switching engine according to an embodiment of the present application;

FIG. 4 is a schematic diagram illustrating a frequency offset change reason of a WSS according to an embodiment of the present application;

fig. 5 is a schematic structural diagram of a frequency offset processing system according to an embodiment of the present application;

fig. 6 is a schematic structural diagram of a frequency offset processing apparatus according to an embodiment of the present application;

fig. 7 is a flowchart illustrating a frequency offset processing method according to an embodiment of the present application;

fig. 8 is a schematic distribution diagram of a switching unit corresponding to a target channel according to an embodiment of the present application;

fig. 9 is a schematic flowchart of a method for detecting a frequency offset drift amount according to an embodiment of the present application;

FIG. 10 is a graph illustrating a target filtered spectrum according to an embodiment of the present application;

fig. 11 is a schematic structural diagram of another frequency offset processing apparatus according to an embodiment of the present application;

fig. 12 is a schematic diagram of another graph of a target filtered spectrum provided by an embodiment of the present application;

fig. 13 is a schematic flowchart of another frequency offset drift amount detection method according to an embodiment of the present application;

fig. 14 is a schematic diagram of a preset filter spectrum of a second switching unit according to an embodiment of the present application;

fig. 15 is a schematic structural diagram of another frequency offset processing apparatus according to an embodiment of the present application;

fig. 16 is a schematic structural diagram of another frequency offset processing apparatus according to an embodiment of the present application;

fig. 17 is a schematic structural diagram of another frequency offset processing apparatus according to an embodiment of the present application.

Detailed Description

To facilitate an understanding and description of the embodiments of the present application, several concepts to be referred to by the embodiments of the present application will be explained and illustrated below.

1. Wavelength selective switch WSS

Referring to fig. 1, fig. 1 is a schematic diagram of an internal structure of a WSS according to an embodiment of the present application. As shown in fig. 1, the WSS may mainly include three functional modules, a grating 101, a main lens 102, and a switching engine 103. In an actual communication process, an input optical signal including a plurality of wavelengths is input from an input terminal of the WSS. Then, the input optical signal is dispersed into a plurality of optical signals having different wavelengths by the grating 101 and is irradiated on the main lens 102, respectively. These optical signals with different wavelengths are then refracted by the lens and are irradiated as parallel light at different positions on the switching engine 103. Then, the switching engine 103 may switch the optical signals at different positions to different output ports of the WSS for output, thereby implementing a function of selecting different wavelengths of the input optical signals. For example, the input optical signal received by the input end includes a first optical signal with a wavelength λ 1 and a second optical signal with a wavelength λ 2, and the input optical signal is scattered into the first optical signal and the second optical signal which are independent of each other after passing through the grating 101. Then, the main lens 102 makes the first optical signal and the second optical signal parallel to each other and simultaneously irradiates on the position L1 and the position L2 of the switching engine 103. Then, the switching engine 103 may switch the first optical signal at the position L1 to the first output terminal of the WSS for output, and switch the second optical signal at the position L2 to the second output terminal of the WSS for output, thereby completing the selection of the first optical signal and the second optical signal.

It should be further added that the configuration information of the WSS indicates that the WSS has a plurality of channels in advance, each channel corresponds to a preset wavelength range, and the preset wavelength range includes at least one preset wavelength. In practical applications, the wavelength of the optical signal that can pass through each channel is usually characterized by a center wavelength within a preset wavelength range of each channel. Each channel has a certain width, which may be 50GHz, 100GHz or other values, and the application is not limited in particular.

It should be understood that the structure shown in fig. 1 is only a schematic structure, and in practical applications, the WSS may further include other possible structures or functional units, and the present application is not limited in particular.

2. Switching Engine 103

The switching engine 103 is a key functional unit of the WSS, and is mainly used for switching optical signals with different wavelengths to corresponding output ports of the WSS according to different requirements. Referring to fig. 2, fig. 2 is a schematic diagram illustrating an incident light direction of the switching engine 103 according to an embodiment of the present disclosure. As shown in fig. 2, switching engine 103 may include a plurality of switching subunits, which are generally uniformly distributed on switching engine 103. Each switching subunit may reflect or transmit its received optical signal to some output of the WSS. In the actual use process, the location of the switching subunit on the switching engine 103 is not changed, and each switching subunit is preset with a subunit identifier to indicate its location on the switching engine 103 and distinguish it from other switching subunits. Alternatively, the subunit identification may specifically be a serial number corresponding to the location of each switching subunit on switching engine 103. For example, the corresponding identifier of the switching subunit 1, the switching subunit 2, or the switching subunit 3 is serial number 1, serial number 2, or serial number 3. Alternatively, the subunit identification may be a row number and a column number of each switching subunit arranged on switching engine 103. The identification of the switching subunit 1 as in the figure may also be (1, 1), characterizing its first column arranged in a first row.

Each channel of the WSS includes one or more switching elements on switching engine 103. Wherein each switching unit may be composed of one or more columns of switching subunits on switching engine 103, and different switching units may simultaneously contain one or more columns of the same switching subunits. As shown in the figure, the switching unit A1 is composed of 16 switching subunits in one row, and the switching unit A2 is composed of 32 switching subunits in two rows. Each switching unit also contains a unit identifier to indicate location and distinguish one from another. In an alternative implementation, the unit identifier of the switching unit may be a preset serial number. For example, the unit id of the switching unit A1 may be the serial number 1, and the unit id of the switching unit A2 may be the serial number 2. Alternatively, the unit identifier of the switching unit may be a column number of a switching subunit included in the switching unit. For example, the exchange unit A1 may use the column number 3 where the exchange subunit included therein is located as the unit identifier. The exchange unit A2 can take the column numbers (3, 4) of the exchange subunits contained therein as unit identifications. In another alternative implementation, each switching unit can also use a preset position of its included switching subunit in the dispersion direction of the switching engine 103 as a unit identifier. It should be noted that the WSS is calibrated with a plurality of preset positions in the dispersion direction of the switching engine 103, and each switching subunit corresponds to a specific preset position in the plurality of preset positions. As shown in fig. 2 at position 0 to position 8. Of course, it is understood that the granularity of these preset positions may be smaller, for example, the position 0 to the position 1 may be refined into the position 0.1, the position 0.2 to the position 1. The granularity of the preset position may be divided according to the actual application, and the application is not particularly limited. If the preset position of the switching subunit included in the switching unit A1 in the dispersion direction of the switching engine 103 is 2, the unit identifier of the switching unit A1 is 2. The preset positions of the switching subunit included in the switching unit A2 in the dispersion direction of the switching engine 103 are 1 and 2, and the unit identifier of the switching unit A1 may be (1, 2) or 1.5.

Here, the switching engine 103 may be a liquid crystal on silicon (LCoS), a micro-electro-mechanical system (MEMS), or other devices. When the switching engine 103 is a liquid crystal on silicon, the switching subunit is specifically a pixel on the liquid crystal on silicon, and the switching unit is one or more pixels on the liquid crystal on silicon. Preferably, the switching units are specifically one or more columns of pixel points on the liquid crystal on silicon. When the switching engine 103 is a mems, the switching sub-unit is a mirror in the mems, and the switching unit is one or more mirrors in the mems.

Further, in practical applications, the position of the optical spot (i.e. the first optical spot shown in the figure) generated on the switching engine 103 by a certain optical signal is usually described by the corresponding preset position of the first optical spot in the dispersion direction of the switching engine 103. For example, as shown in fig. 2, the first light spot corresponds to a position 6.1 in the dispersion direction of the switching engine 103, and the position of the first light spot on the switching engine 103 can be expressed as 6.1.

It should be added that after the WSS calibration is completed, one channel of the WSS passes only the optical signal at the preset wavelength, and the billing unit included in the switching engine 103 of the channel is also preset. Therefore, the position where the optical signal passing through the channel generates the optical spot on the switching engine 103 is also set in advance. Therefore, the position of the optical spot generated by the optical signal in the dispersion direction and the wavelength of the optical signal have a predetermined conversion relationship, and the position of the optical spot in the dispersion direction and the wavelength of the optical signal can be converted into each other by the conversion relationship.

3. Traffic channel and non-traffic channel

In actual communication, the WSS generally operates in one or more predetermined communication bands. For the switching engine 103 of the WSS, a region on which a communication band corresponds may be referred to as a communication region, and a region other than the communication region may be referred to as a non-communication region. For example, please refer to fig. 3, fig. 3 is a schematic diagram illustrating a communication area division of a switching engine according to an embodiment of the present application. As shown in fig. 3, assuming that the WSS operates in a C-band (i.e., C-band) and an L-band (i.e., L-band), a region corresponding to the C-band and a region corresponding to the L-band on the switching engine 103 are communication regions, and a region not corresponding to either the C-band or the L-band is a non-communication region. During use, the switching units in the communication area may receive the optical signal, and the switching units in the non-communication area must not receive the optical signal. In this way, for a plurality of preset channels of the WSS, if the wavelengths corresponding to some channels are within the preset communication band (or the communication areas of the switching units included in some channels on the switching engine 103), these channels are the traffic channels of the WSS. Traffic optical signals may pass through these traffic channels during a particular communication session. If the wavelengths corresponding to some channels are not in the preset band (or the switching units included in some channels are in the non-communication area on the switching engine 103), these channels are the non-traffic channels of the WSS. In a particular communication process, traffic optical signals must not pass through these non-traffic channels. For example, when the WSS operates in the C-band and/or L-band, certain channels are traffic channels if the wavelength pairs of the optical signals that they can pass through are within the C-band and/or L-band. Certain channels are non-traffic channels if the wavelengths of the optical signals through which they can pass are not within the C-band and/or L-band.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the concepts described above and other drawings provided in the embodiments of the present application.

In the prior art, a main function of the WSS is to implement wavelength selection of an optical signal, and a filtering spectrum frequency offset (hereinafter, referred to as frequency offset) of the WSS is always regarded as an important performance index of the WSS. Referring to fig. 4, fig. 4 is a schematic diagram illustrating a frequency offset change reason of a WSS according to an embodiment of the present application. As shown in fig. 4, during the use of the WSS, as the internal devices thereof age or the external environment changes (e.g., the ambient temperature, the air pressure, etc.) the internal devices thereof may change in position, such as the grating 101 shown in fig. 4, slightly deflecting. These variations have the result that the position of the light spot generated on the switching engine 103 by the optical signal passed by each channel varies. However, the switching engine 103 will still send the optical signal at each position to the predetermined output port, and will not change due to the change of the position of the optical spot, which will eventually cause the center wavelength of the filtered spectrum of the WSS to change, thereby causing the frequency offset to change. As shown in fig. 4, taking the first optical signal as an example, the optical spot generated by the first optical signal on the switching engine 103 is at the position L1 before the optical grating 101 is not deflected. After the optical grating 101 is deflected, the optical spot generated on the switching engine 103 by the first optical signal is shifted from the position L1 to the position L3. Although the position of the light spot generated by the first optical signal on the switching engine 103 has changed, the switching engine 103 still switches the optical signal corresponding to the light spot at the position L1 to the first output terminal as the first optical signal, and the real first optical signal is switched to the third output terminal corresponding to the position L3, which finally causes some shift of the center wavelength of the filtered spectrum of the WSS. Because the change of the frequency offset of the WSS may cause additional transmission cost, in the prior art, the change of the frequency offset of the WSS is detected first, and then the frequency offset of the WSS is compensated according to the detected change to maintain the stability of the frequency offset of the WSS, thereby overcoming the additional transmission cost. However, in the prior art, the variation of the frequency offset of some channels of the WSS is usually measured first, and then the variation of the frequency offset of each channel of the WSS is obtained by fitting the variation of the frequency offset of the several channels. The variation of the WSS frequency offset measured in the prior art includes a factory frequency offset (i.e., a beginning of life (BOL) frequency offset) generated by the optical design, device assembly, and calibration algorithm of the WSS, and the factory frequency offset has no regularity. Therefore, in the prior art, there is a large error in obtaining the variation of the frequency offset of each channel of the WSS by fitting the variation of the frequency offset of several channels. Therefore, the frequency offset compensation of the WSS cannot be effectively and accurately realized, and the performance of the WSS cannot be ensured.

Therefore, the technical problem to be solved by the application is as follows: how to perform effective and accurate frequency offset compensation on the WSS.

Referring to fig. 5, fig. 5 is a schematic structural diagram of a frequency offset processing system according to an embodiment of the present application. As shown in fig. 5, the frequency offset processing system may mainly include a frequency offset processing apparatus 50 and a WSS 51 establishing optical and electrical connection with the frequency offset processing apparatus 50. Here, the specific structure of the WSS 51 is as described above, and is not described here. The frequency offset processing method provided in the embodiment of the present application is applicable to the frequency offset processing apparatus 50 in the frequency offset processing system. In practical applications, the frequency offset processing apparatus 50 may be used to determine the amount of frequency offset drift for each of one or more channels of the WSS 51. The frequency offset drift amount of any channel is used for indicating the difference degree between the frequency offset of any channel at the first time and the frequency offset of any channel at the second time. The first time and the second time are different times, and the first time is before the second time. Preferably, the second time is a time when the frequency offset processing apparatus 50 obtains the frequency offset drift amounts of the one or more channels, and the first time is a time when the WSS first completes configuration parameter calibration (i.e., a factory time) or a time when the WSS last completes frequency offset compensation. The frequency offset processing apparatus 50 may then be configured to perform frequency offset compensation on each of the one or more channels according to the frequency offset drift amount of each of the one or more channels.

Here, since the frequency offset drift amount of each channel of the WSS 51 measured by the frequency offset processing apparatus 50 does not include the factory frequency offset described above, the frequency offset processing apparatus 50 can perform accurate frequency offset compensation on the WSS 51 through the frequency offset drift amount of each channel, thereby ensuring that the performance of the WSS can be maintained at a high level.

Further, please refer to fig. 6, where fig. 6 is a schematic structural diagram of a frequency offset processing apparatus according to an embodiment of the present application. As shown in fig. 6, the frequency offset processing apparatus 50 may specifically include a processor 501, an optical signal generator 502, and a photodetector 503. The processor 501 is electrically connected with the optical signal generator 502, the photodetector 503 and the WSS 51, and the optical signal generator 502 and the photodetector 503 are also optically connected with the WSS 51. The processor 501 may be a processor with a data processing function or a system on chip with a data processing capability. The optical signal generator 502 may be a laser or the like. During the execution of the frequency offset processing method provided by the present application by the frequency offset processing apparatus 50, the frequency offset processing apparatus 50 may control the optical signal generator 502 to generate an optical signal with a specified wavelength through the processor 501, and send the optical signal to the input end of the WSS 51. The photodetector 503 may collect the optical power at the input and detection outputs of the WSS 51 and send the optical power at the input and detection outputs to the processor 501. The processor 501 may determine a frequency offset drift amount of each channel of the WSS 51 according to the obtained optical power at the input end and the detection output end, and further perform frequency offset compensation on each channel according to the frequency offset drift amount of each channel.

It should be noted that, since the switching engine in the WSS 51 can switch the optical signal passing through a certain channel to one or more ports of the WSS for output, and there are also one or more channels actually detected by the frequency offset processing apparatus 50 (for convenience of distinction, the target channel is used instead of the description below), the detection output shown in fig. 6 may refer to a certain output of the WSS 51 that is dedicated to frequency offset amount detection. In this case, the optical signal passing through each of the one or more target channels to be actually detected, which will be described later, is switched to the output end by the switching engine, and the photodetector 503 is connected to the output end separately. Or, the detection output end may also refer to an output end preset for frequency offset drift amount detection for each target channel. In this case, the optical signal passing through each target channel is respectively switched by the switching engine to the respective preset output terminal for detecting the offset drift amount. At this time, the photodetectors 503 may establish optical connections with these output terminals, respectively. Hereinafter, a description will be given taking a scenario in which the detection output terminal is the only port as an example.

A detailed description will be given below of a frequency offset processing method provided in the embodiment of the present application, with reference to the structure of the frequency offset processing system and the frequency offset processing apparatus 50 described above.

Referring to fig. 7, fig. 7 is a flowchart illustrating a frequency offset processing method according to an embodiment of the present application. The frequency offset processing method can be specifically executed by the processor 501 in the frequency offset processing apparatus 50 described above. It is assumed that WSS 51 operates in the C-band and L-band. As shown in fig. 7, the method includes the steps of:

s71, the processor 501 determines an amount of frequency offset drift for each of one or more channels.

S72, the processor 501 performs frequency offset compensation on each channel according to the frequency offset drift amount of each channel.

In some possible implementations, the processor 501 may determine an amount of frequency offset drift for each of one or more channels of the WSS, as described in step 71. Here, the one or more channels may be a partial channel of the WSS or all channels of the WSS. Hereinafter, the number N0 of the one or more channels is assumed, where N0 is a positive integer greater than or equal to 1. The frequency offset drift amount of any one of the N0 channels indicates the difference degree between the frequency offset of the any one channel at the current second time and the frequency offset of the any one channel at the first time. The first time here precedes the second time. In this embodiment, the second time is taken as the time when the processor 501 obtains the frequency offset drift amount of each channel, and the first time is taken as the factory time of the WSS 51.

In a specific implementation, the processor 501 may first determine one or more target channels from the N0 channels, where N1 target channels are assumed, and N1 is a positive integer smaller than or equal to N0. In practical application, the N1 target channels may be service channels through which no service optical signal passes in the N0 channels, so that interference of a frequency offset detection process on a service of the WSS may be avoided. Alternatively, the N1 target channels may be non-traffic channels among the N0 channels. Still alternatively, the N1 target channels may be a part of traffic channels and a part of non-traffic channels in the N0 channels. Preferably, N1 may be 6 or 8, and the positions of the N1 target channels on the switching unit included in the switching engine are relatively distributed (it may also be understood that the N1 target channels are relatively distributed in the corresponding area on the switching engine). The channels distributed in a relatively dispersed area corresponding to the switching engine are selected as the target channels, so that the frequency offset drift amount of each channel in the one or more channels can be accurately obtained through the subsequent fitting of the frequency offset drift amount of each target channel, and the detection precision of the frequency offset drift amount of each channel is improved.

For example, please refer to fig. 8, fig. 8 is a schematic distribution diagram of a switching unit corresponding to a target channel according to an embodiment of the present application, where it is assumed that each target channel includes a switching unit on a switching engine. As shown in fig. 8, the processor 501 selects 3 non-traffic channels from the channels of N0, and the switching units (e.g., switching unit A3 and switching unit A4) included in 2 non-traffic channels are distributed in the non-communication area at the edge of the switching engine, and the switching units (e.g., switching unit A5) included in 1 non-traffic channel are distributed in the non-communication area at the middle of the switching engine. Processor 501 may also select 2 traffic channels from the N0 channels, and the two traffic channels include switching units (e.g., switching unit A6 and switching unit A7) distributed in the communication area at the middle of the switching engine. Processor 501 may then determine these 5 channels as target channels. Here, there are many different implementations of selecting the target channel, as long as it is ensured that no service optical signal passes through the target channel, and the description of the other different implementations is not repeated in this application.

Further, after the processor 501 determines the N1 target channels, the frequency offset drift amount may be detected for each target channel in the N1 target channels, so as to obtain a frequency offset drift amount corresponding to each target channel. Several methods for detecting the frequency offset drift amount of the target channel according to the embodiments of the present application will be described in detail below with reference to the structure of the frequency offset processing apparatus 50 shown in fig. 6. It should be noted that, since the detection process of the processor 501 for the frequency offset drift amount of each target channel is similar, the following will describe a process of determining the frequency offset drift amount of each target channel by the processor 501 by taking the detection process of the frequency offset drift amount of the first target channel included in the above N1 target channels as an example.

The detection method comprises the following steps:

referring to fig. 9, fig. 9 is a flowchart illustrating a method for detecting a frequency offset drift amount according to an embodiment of the present application. As shown in fig. 9, the method for detecting the frequency offset drift amount includes the steps of:

s7101, the processor 501 obtains a target filtered spectrum of the first switching unit.

S7102, the processor 501 determines a frequency offset drift amount of the first target channel according to the center wavelength of the target filter spectrum and the wavelength corresponding to the first switching unit at the first time.

In some possible implementations, as described in step S7101, the processor 501 may first obtain a target filtered spectrum of a first switching unit included on the switching engine for a first target channel. Here, the first switching unit is any one of one or more switching units included in a switching engine of the first target channel. Preferably, the first switching unit is a switching unit of which the first target channel is relatively centrally located among the one or more switching units included on the switching engine.

In a specific implementation, the processor 501 may extract one or more wavelengths included in a preset wavelength range corresponding to the first target channel from configuration information of the WSS 51 (for convenience of distinction, the description will be replaced with a first preset wavelength hereinafter), where the configuration information of the WSS 51 is configuration information of the WSS 51 at the first time. Assuming that the predetermined wavelength range includes N2 different first predetermined wavelengths, N2 is a positive integer greater than 1. Then, the processor 501 may control the optical signal generator 502 to perform wavelength scanning on the first switching unit by using the optical signal at each first preset wavelength in the N2 first preset wavelengths, and obtain the input power (for convenience of distinction, the description will be replaced by the first input power) and the output power (for convenience of distinction, the description will be replaced by the first output power) of the WSS 51 at each optical signal at each first preset wavelength by using the photodetector 503. Here, each optical signal at the first preset wavelength corresponds to one first input optical power and one first output optical power, that is, N2 first input optical powers and N2 first output optical powers that can be acquired by the processor 501. Specifically, after acquiring the N2 first preset wavelengths, the processor 501 may send a first control instruction to the optical signal generator 502. After receiving the first control command, the optical signal generator 502 may generate an optical signal at a first preset wavelength λ 1 included in the N2 first preset wavelengths (for convenience of understanding and distinction, the description will be replaced with a third optical signal hereinafter). The optical signal generator 502 may then send the third optical signal to the input of the WSS 51. The WSS 51 then outputs the third optical signal at its detection output. Meanwhile, the photodetector 503 may perform optical power detection on the input end and the detection output end of the WSS 51 to obtain a first input power and a first output power of the input end and the detection output end of the WSS 51 under a third optical signal, and send the first input power and the second input power under the third optical signal to the processor 501. Thereafter, the processor 501 may generate and send a second control instruction to the optical signal generator 502. After receiving the second control command, the optical signal generator may generate an optical signal at a first preset wavelength λ 2 included in the N2 first preset wavelengths (for convenience of understanding and distinction, the description will be replaced with a fourth optical signal hereinafter). The optical signal generator 502 may then send the fourth optical signal to the input of the WSS 51. The WSS 51 then outputs the fourth optical signal at its detection output. Meanwhile, the photodetector 503 may perform optical power detection on the input end and the detection output end of the WSS 51 to obtain a first input power and a first output power of the input end and the detection output end of the WSS 51 under a fourth optical signal, and send the first input power and the second input power under the fourth optical signal to the processor 501. By analogy, until the N2 first preset wavelengths are traversed, the processor 501 may obtain the first input power and the first output power of the optical signal with each first preset wavelength in the N2 first preset wavelengths.

Optionally, the processor 501 may also send only one third control instruction to the optical signal generator, and after receiving the third control instruction, the optical signal generator 502 may generate and send optical signals with different first preset wavelengths to the WSS 51 at different preset times. The photodetector may then measure a first input power and a first output power of the WSS 51 at each of the first preset wavelengths of the optical signal, and send the first input power and the first output power at each of the first preset wavelengths of the optical signal to the processor 501. This can simplify the signaling or signal interaction between the processor 501 and the optical signal generator 502 and the photodetector 503, and reduce the data processing pressure of the processor 501.

After the processor 501 obtains the first input power and the first output power of each optical signal with the first preset wavelength, it may determine the target filter spectrum of the first switching unit according to the first input power and the first output power of each optical signal with the first preset wavelength. It should be noted that the target filtered spectrum of the first switching unit indicates the corresponding insertion loss value of the first switching unit at each first preset wavelength (for convenience of distinction, the description will be replaced by the first insertion loss value hereinafter). A first insertion loss value corresponding to any one of the N2 first preset wavelengths is a difference between a first output power and a first input power at any one of the first preset wavelengths.

In an alternative implementation, the processor 501 may calculate a difference between the first output power and the first input power of the optical signal at each first preset wavelength to obtain a first insertion loss value at each first preset wavelength. For example, assuming that the processor 501 obtains that the first output power corresponding to the first preset wavelength λ 1 is t1 and the corresponding first input power is t2, the processor 501 may determine that the first insertion loss value at the first preset wavelength λ 1 is d1= t1-t2. Then, the processor 501 may determine the target filter spectrum corresponding to the first switching unit according to the N2 first preset wavelengths and the first insertion loss value at each first preset wavelength. For example, please refer to fig. 10 together, and fig. 10 is a graph illustrating a target filtered spectrum according to an embodiment of the present application. As shown in fig. 10, the target filter spectrum indicates a first insertion loss value corresponding to each first predetermined wavelength with the first predetermined wavelength as the horizontal axis and the first insertion loss value as the vertical axis, such as the first predetermined wavelength λ 1 and the first predetermined wavelength λ N2 corresponding to the first insertion loss d1, the first predetermined wavelength λ 2 and the first predetermined wavelength λ N2-1 corresponding to the first insertion loss d2, and so on.

In another alternative implementation, please refer to fig. 11 together, and fig. 11 is a schematic structural diagram of another frequency offset processing apparatus provided in this embodiment of the present application. As shown in fig. 11, the frequency offset processing apparatus 50 may further include a wavelength meter 504. The wavelength meter 504 is optically connected to the input of the WSS 51 and electrically connected to the processor 501. In the process of controlling the optoelectronic signal generator 102 to perform wavelength scanning on the WSS 51 by using the optical signal at each first preset wavelength, the processor 501 may further control the wavelength meter 504 to detect the wavelength of the optical signal at the input end of the WSS 51 when the optical signal at each first preset wavelength is input to the WSS 51 (for convenience of distinction, the description will be replaced by the first input detection wavelength). For example, when the optical signal generator 502 inputs an optical signal at a first preset wavelength λ 1 to the input port of the WSS 51, the processor 501 may further control the wavelength meter 504 to detect the wavelength of the optical signal at the input port of the WSS 51, and the detection result is determined as a first input detection wavelength x1 corresponding to the first preset wavelength λ 1. Similarly, when the optical signal generator 502 inputs the optical signal at the first preset wavelength λ 2 to the input port of the WSS 51, the processor 501 may further control the wavelength meter 504 to detect the wavelength of the optical signal at the input port of the WSS 51, and determine the detection result as the first input detection wavelength x2 corresponding to the first preset wavelength λ 2. By analogy, the wavelength meter 504 may finally detect N2 first input detection wavelengths corresponding to the N2 first preset wavelengths. Then, the processor 501 may calculate a difference between the first output power and the first input power of the optical signal at each first preset wavelength to obtain a first insertion loss value at each first preset wavelength. Then, the processor 501 may determine the target filter spectrum corresponding to the first switching unit according to the N2 first input detection wavelengths and the first insertion loss value at each first preset wavelength. For example, please refer to fig. 12 together, fig. 12 is a schematic diagram of another curve of the target filtered spectrum according to the embodiment of the present application. As shown in fig. 12, the target filter spectrum indicates a first insertion loss value at a first predetermined wavelength corresponding to each first input detection wavelength, such as the first input detection wave x1 and the first input detection wave xN2 corresponding to the first insertion loss value d6, the first input detection wave x2 and the first input detection wave xN2-1 corresponding to the first insertion loss value d5, and so on, with the first input detection wavelength as a horizontal axis and the first insertion loss value as a vertical axis.

Here, the processor 501 determines the target filter spectrum according to the N2 first input detection wavelengths and the first insertion loss value at each first preset wavelength, so that the problem of inaccurate target filter spectrum caused by an error in the wavelength of the optical signal output by the optical signal generator 502 can be avoided, and the accuracy of the measured target filter spectrum can be improved.

In some possible implementation manners, as shown in step S7102, after the target filter spectrum is obtained, the processor 501 may determine a center wavelength of the target filter spectrum, and determine a frequency offset drift amount of the first target channel according to the center wavelength of the target filter spectrum and a wavelength corresponding to the first switching unit at the first time. Here, the wavelength corresponding to the first switching unit at the first time refers to the wavelength of the optical signal to be switched by the first switching unit, which is predetermined at the first time.

In a specific implementation, the processor 501 may determine the center wavelength of the target filtered spectrum first. Optionally, the processor 501 may determine a minimum first insertion loss value from the N2 first insertion loss values, and determine a first preset wavelength corresponding to the minimum first insertion loss value as a center wavelength of the target filter spectrum. As shown in fig. 10, if the absolute value of the first insertion loss value d3 in the target filter spectrum is the minimum, the first preset wavelength value λ 10 corresponding to the first insertion loss value d3 is the center wavelength of the target filter spectrum. Alternatively, as shown in fig. 12, if the absolute value of the first insertion loss value d4 in the target filter spectrum is the minimum, the first detection wavelength value x10 corresponding to the first insertion loss value d4 is the central wavelength of the target filter spectrum. Optionally, the processor 501 may further obtain a 3dB center wavelength of the target filter spectrum, and determine the 3dB center wavelength as the center wavelength of the target filter spectrum. For example, referring to fig. 10, the processor 501 may determine a first insertion loss value d3 with the smallest absolute value indicated by the target filter spectrum, and then calculate the difference between the first insertion loss value d3 and 3dB to obtain the first insertion loss value d3-3dB (assuming that d3-3dB = d 2). Then, the processor 501 may obtain a first preset wavelength λ 2 and a first preset wavelength λ N2-1 corresponding to the first insertion loss value d2, and an average value of the first preset wavelength λ 2 and the first preset wavelength λ N2-1 is a 3dB central wavelength of the target filter spectrum, and the processor 501 may determine the average value of the first preset wavelength λ 2 and the first preset wavelength λ N2-1 as the central wavelength of the target filter spectrum, where it can be understood that the processor 501 may also determine the central wavelength of the target filter spectrum by using other possible implementation manners (for example, determining the central wavelength of the target filter spectrum by using the central wavelength of 2.8dB of the target filter spectrum, etc.), which is not particularly limited in this application.

It should be particularly noted that, in the frequency offset detection process, the method for determining the center wavelength of the target filter spectrum by the processor 501 needs to be the same as the method for determining the center wavelength of the filter spectrum used in the calibration process of the WSS 51, so that an error of the center wavelength caused by adopting different determination methods can be avoided, and the frequency offset drift amount of the first target channel determined based on the center wavelength of the target filter spectrum can be more accurate.

After the processor 501 acquires the center wavelength of the target filter spectrum, the processor 501 may further extract the wavelength corresponding to the first switching unit at the first time from the configuration information of the WSS 51. Then, the processor 501 may calculate a difference between the center wavelength of the target filtered spectrum and the wavelength corresponding to the first switching unit at the first time, and determine the difference as the frequency offset drift amount of the first target channel.

The target filtering spectrum of the first switching unit is obtained by performing wavelength scanning on the first switching unit, and then the frequency offset drift amount of the first target channel is directly determined according to the center wavelength of the target filtering spectrum and the wavelength corresponding to the first switching unit at the first moment.

And a second detection mode:

referring to fig. 13, fig. 13 is a flowchart illustrating a further method for detecting a frequency offset drift amount according to an embodiment of the present application. As shown in fig. 13, the method for detecting the frequency offset drift amount includes the steps of:

s7111, when the optical signal with the second preset wavelength passes through the first target channel, the processor 501 obtains a target position of a light spot generated on the switching engine by the optical signal with the second preset wavelength.

S7112, the processor 501 determines a frequency offset drift amount of the first target channel according to the wavelength corresponding to the target location at the first time and a second preset wavelength.

In some possible implementations, as shown in step S7111, the processor 501 may first control the optical signal generator 502 to generate and transmit an optical signal at a second preset wavelength to the WSS 51 (for understanding, the description will be replaced with a fifth optical signal). The optical processor may then obtain a target position of the spot generated on the switching engine by the fifth optical signal. Here, the second predetermined wavelength may be a wavelength of a passable optical signal predetermined by the first target channel. Of course, the second preset wavelength may also be another preset wavelength in the preset wavelength range corresponding to the first target channel, and the application is not limited specifically.

In a specific implementation, the processor 501 may determine an insertion loss value (for convenience of distinction, the following description will be replaced with a second insertion loss value) of each of at least two switching units (for convenience of distinction, the following description will be replaced with a second switching unit) included in the switching engine, of the first target channel, at the second preset wavelength. Here, the at least two second switching units included on the switching engine of the first target channel may be at least two of the plurality of switching units included on the switching engine of the first target channel indicated by the configuration information of the WSS 51. Optionally, when the configuration information of the WSS 51 indicates that the first target channel only includes one switching unit A1 on the switching engine, the processor 501 may also select at least one switching unit from an area near the switching unit A1 as the second switching unit according to a preset switching unit filtering rule. Optionally, the switching unit screening rule may be a rule that a distance between the switching unit a and the switching unit a is less than or equal to a preset distance, and the application is not particularly limited. Specifically, the processor 501 may generate and send a third control instruction to the optical signal generator 502. The optical signal generator 502 may generate and transmit the fifth optical signal to the input terminal of the WSS 51 after receiving the third control instruction. Then, the processor 501 may send a fourth control instruction to the WSS 51. After receiving the fourth control instruction, the WSS 51 may respectively start each of the at least two second switching units. For example, after receiving the fourth control instruction, the WSS 51 may sequentially start the at least two second switching units according to a preset start sequence and a preset start cycle. It should be noted here that the WSS 51 starts only one second switching unit at the same time. For example, when the WSS 51 activates the second switching unit B1, all the other second switching units except the second switching unit B1 in the at least two second switching units are in the off state. The photodetector 503 can detect the optical power at the input end of the WSS 51 (for the convenience of distinguishing, the second input power will be used hereinafter) and detect the optical power at the output end (for the convenience of distinguishing, the second output power will be used hereinafter) when each second switching unit is turned on, so as to obtain the second input power and the second output power of each second switching unit at the second preset wavelength. The photodetector 503 may then send the second input power and the second output power of each second switching unit at the second preset wavelength to the processor 501. Here, the photodetector 503 may send the second input power and the second output power of one second switching unit to the processor 501 every time the second input power and the second output power of the second switching unit are acquired, or may send the second input power and the second output power of all the second switching units to the processor 501 after the second input power and the second output power of all the second switching units are acquired, which is not limited in this application. Then, the processor 501 may determine a second insertion loss value of each second switching unit at the second preset wavelength according to the second input power and the second output power of each second switching unit at the second preset wavelength. Specifically, the processor 501 may calculate a difference between a second output power and a second input power of each second switching unit at the second preset wavelength, and determine each difference as a second insertion loss value of each second switching unit at the second preset wavelength.

After the processor 501 obtains the second insertion loss value of each second switching unit at the second preset wavelength, the processor 501 may determine the target position of the light spot generated by the fifth optical signal on the switching engine according to the second insertion loss value of each second switching unit at the second preset wavelength and the preset filter spectrum of each second switching unit at the first time. It should be noted that the preset filter spectrum of any second switching unit can be recorded by the configuration information of the WSS 51. The preset filtering spectrum of any second switching unit indicates a preset insertion loss value corresponding to a plurality of preset positions of any second switching unit in the dispersion direction of the switching engine. Here, the plurality of predetermined positions in the dispersion direction of the switching engine are as described above, and will not be described herein again.

Specifically, it is assumed that the number of the second switching units is N3, and N3 is a positive integer greater than or equal to 2. The processor 501 may first extract a preset filtered spectrum of each second switching unit from the configuration information of the WSS 51. It should be noted that, if only the filter spectrum (described below as the original filter spectrum instead of the original filter spectrum) indicating the preset insertion loss values corresponding to different preset wavelengths is recorded in the configuration information of the WSS 51, the processor 501 may process the original filter spectrum of each second switching unit according to the aforementioned conversion relationship between the preset wavelength and the preset position to obtain the preset filter spectrum of each second switching unit. Then, the processor 501 may determine, according to the preset filter spectrum of each second switching unit, a preset insertion loss value set corresponding to each preset position in the plurality of preset positions (here, N4 preset positions are assumed, and N4 is a positive integer greater than or equal to 1). Here, the preset insertion loss value set corresponding to any one preset position includes N3 preset insertion loss values corresponding to the N3 second switching units at the any one preset position. For example, please refer to fig. 14 together, wherein fig. 14 is a schematic diagram of a preset filter spectrum of the second switching unit according to an embodiment of the present disclosure. Here, it is assumed that the N3 second switching units include a second switching unit A9, a second switching unit a10, a second switching unit a11, and a second switching unit a12, and the number N4 of the preset positions is 12. As shown in fig. 14, the processor 501 may obtain a first preset filter spectrum, a second preset filter spectrum, a third preset filter spectrum and a fourth preset filter spectrum corresponding to the second switching unit A9, the second switching unit a10, the second switching unit a11 and the second switching unit a 12. The first preset filter spectrum, the second preset filter spectrum, the third preset filter spectrum and the fourth preset filter spectrum all use a preset position as a horizontal axis and a preset insertion loss value as a longitudinal axis. Each preset filtered spectrum indicates a corresponding preset insertion loss value at 12 preset positions p0 to p11 of each second switching unit. Then, the processor 501 may extract the preset insertion loss values corresponding to the second switching unit A9, the second switching unit a10, the second switching unit a11, and the second switching unit a12 at each preset position from the first preset filter spectrum, the second preset filter spectrum, the third preset filter spectrum, and the fourth preset filter spectrum, respectively, so as to form a preset insertion loss value set corresponding to each preset position. For example, the processor 501 may extract the preset insertion loss values s1, s2, s3, and s4 corresponding to the second switching unit A9, the second switching unit a10, the second switching unit a11, and the second switching unit a12 at the preset position p4 from the first preset filter spectrum, the second preset filter spectrum, the third preset filter spectrum, and the fourth preset filter spectrum. Then, the processor 501 may form the preset insertion loss values s1, s2, s3, and s4 into a preset insertion loss value set corresponding to the preset position p 4. By analogy, the processor can obtain the preset insertion loss value set corresponding to each preset position in the 12 preset positions after traversing the 12 preset positions.

Further, after obtaining the preset insertion loss value set corresponding to each preset position, the processor 501 may determine, from the plurality of preset positions, a target position of a light spot generated by a fifth optical signal on the switching engine according to N3 second insertion loss values of the N3 second switching units at a second preset wavelength and the preset insertion loss value set corresponding to each preset position.

Optionally, the processor 501 may determine the first relative insertion loss value set corresponding to each preset position according to the preset insertion loss value set corresponding to each preset position. Here, the first relative insertion loss value group corresponding to any preset position may include a comparison result of any two preset insertion loss values in the preset insertion loss value group corresponding to the any preset position. Specifically, since the process of determining the first relative insertion loss value group corresponding to each preset position by the processor 501 is the same, the process of determining the first relative insertion loss value group corresponding to each preset position by the processor 501 will be described below by taking the process of determining the first relative insertion loss value group corresponding to the preset position p4 shown in fig. 14 as an example. Here, the preset insertion loss value set corresponding to the preset position p4 includes preset insertion loss values s1, s2, s3, and s4. The processor 501 may compare any two of the 4 preset insertion loss values, and form a first relative insertion loss value group of the preset position p4 from a comparison result of any two preset insertion loss values. For example, the processor 501 may subtract every two of the 4 preset insertion loss values to obtain 6 differences s4-s3, s4-s2, s4-s1, s3-s2, s3-s1, and s2-s1, and then the 6 differences constitute a first relative insertion loss value set corresponding to the preset position p 4. Alternatively, the processor 501 may also calculate a ratio of any two of the 4 predetermined insertion loss values, such as s4/s3, s4/s2, s4/s1, s3/s2, s3/s1, and s2/s1, and then form the 6 ratios to form the first relative insertion loss value set of the predetermined position p 1. Of course, the processor 501 may also perform comparison processing on the 4 preset insertion loss values in other manners, and form the first relative insertion loss value group corresponding to the preset position p4 according to the comparison result, which is not limited in this application.

Further, the processor 501 may determine a second relative insertion value set according to a second insertion value of each second switching unit in the fifth optical signal. Specifically, the processor 501 may process the second insertion loss value of each second switching unit under the fifth optical signal by using the same comparison process as described above. For example, two or two of all the second insertion loss values are subtracted from each other, or two of them are compared with each other, and the subtracted difference value or the compared ratio value forms the second relative insertion loss value set. After obtaining the first relative insertion value group and the second relative insertion value group corresponding to each preset position, the processor 501 may determine a target relative insertion value group matching the second relative insertion value group from the N4 first relative insertion value groups. For example, the processor 501 may perform variance calculation on the second relative insertion value group and each first relative insertion value group to obtain N4 variances, and then determine the first relative insertion value group corresponding to the variance with the smallest median among the N4 variances as the target insertion value group. Of course, it is understood that the process 101 may also calculate other parameters, such as standard deviation, etc., capable of measuring the deviation degree between the second relative insertion value set and each first relative insertion value set, and then select the target insertion value set according to the magnitudes of the parameters, which is not limited in this application. After determining the target relative insertion loss value set, the processor 501 may determine a preset position corresponding to the target relative insertion loss value set as a target position of a light spot generated on the switching engine by the fifth optical signal.

Here, the processor 501 compares the preset insertion loss values in each preset insertion loss value set with each other to obtain a first relative insertion loss value set corresponding to each preset position, and determines a target relative insertion loss value set from the plurality of first relative insertion loss value sets through variance calculation or the like, so that the plurality of preset insertion loss values included in the determined target relative insertion loss value set are closest to the second insertion loss value of each second exchange unit, and the accuracy of the subsequently determined frequency offset drift amount of the first target channel can be ensured.

Alternatively, the processor 501 may also determine the target position of the light spot generated by the fifth optical signal on the switching engine in other manners, and the application is not limited in particular. For example, the processor 501 may calculate parameters such as euclidean distances and manhattan distances between the N3 second insertion loss values and the preset insertion loss value sets corresponding to each preset position, determine a preset insertion loss value set most similar to the N3 second insertion loss values from a plurality of preset insertion loss value sets according to the magnitudes of the parameters, and determine the preset position corresponding to the preset insertion loss value set as the target position of the light spot generated by the fifth optical signal on the switching engine.

In some possible implementation manners, as shown in step S7112, after the target position is obtained, the processor 501 may extract a wavelength corresponding to the target position from the configuration information of the WSS 51, and determine a frequency offset drift amount of the first target channel according to the wavelength corresponding to the target position and the second preset wavelength. Specifically, after determining the wavelength corresponding to the target position, the processor 501 may calculate a difference between the wavelength corresponding to the target position and the second preset wavelength, and determine the difference as the frequency offset drift amount of the first target channel.

Optionally, referring to fig. 11, in a case that the frequency offset processing apparatus 50 includes the wavelength meter 504, when the WSS 51 opens one second switching unit, the wavelength meter 504 may detect the wavelength of the optical signal at the input port of the WSS 51, so as to obtain the second input detection wavelength corresponding to each second switching unit. After the processor 501 determines the wavelength corresponding to the target position at the first time, the processor 501 may calculate a wavelength average value of a plurality of second input detection wavelengths corresponding to the plurality of second switching units, and determine the frequency offset drift amount of the first target channel according to a difference between the wavelength corresponding to the target position and the wavelength average value. Here, the processor 501 determines the spectrum offset of the first target channel according to the difference between the wavelength corresponding to the target position and the average value of the wavelengths, so as to avoid the problem that the spectrum offset of the first target channel is inaccurate due to the error of the wavelength of the optical signal output by the optical signal generator 502.

In the second detection mode, only the optical signal with the fixed second preset wavelength is used as the input optical signal of the WSS 51 to obtain the second insertion loss value of each second switching unit, and the optical signal generator 502 does not need to frequently adjust the output wavelength, thereby simplifying the control flow of the processor 501. Therefore, on one hand, the performance requirement of the optical signal generator 502 can be lowered, the implementation cost of the frequency offset processing device can be reduced, on the other hand, the implementation process of the frequency offset processing method can be simplified, and the execution efficiency of the frequency offset processing method is improved.

After detecting the frequency offset drift amount of the first target channel, the processor 501 may also perform frequency offset drift amount detection on other target channels in the N1 target channels by using the same detection method, and the specific process may refer to the process for detecting the frequency offset drift amount of the first target channel, which is not described herein again. It should be particularly noted that, during the whole detection process, when the output wavelength of the optical signal generator 502 needs to be adjusted across channels, for example, when the output wavelength thereof is switched from the wavelength required for the first target channel detection to the wavelength required for the second target channel detection, the processor 501 may control the optical signal generator 502 or the optical device connected between the output end of the optical signal generator 502 and the input end of the WSS 51 to temporarily turn off the output of the optical signal generator 502, so as to avoid the interference of the optical signal output by the optical signal generator 502 on the communication signal of the WSS 51. Here, the optical device may be an optical switch or an optical modulator capable of realizing an optical switching function, and the present application is not particularly limited.

After the processor 501 determines the frequency offset drift amount of each target channel of the N1 target channels, the processor 501 may determine the frequency offset drift amount of each channel of the N0 channels according to the frequency offset drift amount of each target channel. Specifically, the processor 501 may perform curve fitting on the frequency offset amounts of the N1 target channels by using a fitting method such as a least square method, an interpolation method, or a polishing method, so as to obtain a frequency offset drift amount curve of the WSS 51, where the frequency offset drift amount curve indicates a frequency offset drift amount corresponding to each of the N0 channels. Then, the processor 501 may obtain a frequency offset drift amount corresponding to each channel.

Here, the processor 501 selects N1 target channels from the N0 channels, then detects a frequency offset drift amount of each target channel, which does not include the factory frequency offset, and then fits the frequency offset drift amount of each target channel to obtain the frequency offset drift amount of each channel in the N0 channels, so that an error caused by the irregularity of the factory frequency offset to the frequency offset drift amount can be avoided, and the detection accuracy of the frequency offset drift amount of each channel is improved.

In some possible implementations, as described in step S72 above, after obtaining the above frequency offset drift amount of each channel, the processor 501 may further perform frequency offset compensation on each channel according to the frequency offset drift amount of each channel. In a specific implementation, the processor 501 may extract, from the configuration information of the WSS 51, a frequency offset corresponding to each channel at the second time, and then compensate, by using the frequency offset drift amount of each channel, the frequency offset corresponding to each channel at the second time, so as to obtain a frequency offset compensated by each channel. For example, if the frequency offset of the channel B1 at the second time is 8pm (picometers), and the measured frequency offset drift amount of the channel B1 is 3pm, the frequency offset of the channel B1 at the first time, which is obtained after the compensation by the processor 501, is 5pm. After obtaining the compensated frequency offset of each channel, the processor 501 may send the compensated frequency offset of each channel to the WSS 51. After receiving the frequency offset compensated by each channel, the WSS 51 may update the frequency offset of each channel stored in the configuration information according to the frequency offset compensated by each channel, so as to complete frequency offset compensation for the WSS 51.

It should be added that, in the process of detecting the frequency offset drift amount described above, the optical signal generator 502 can output an optical signal at a certain wavelength at the same time, and therefore, the detection of the frequency offset drift amount needs to be completed channel by channel. In a specific implementation, the optical signal generator 502 may include a tunable laser 5020, and the tunable laser 5020 is connected to the input terminals of the control module 101 and the WSS 51, respectively. In the actual detection process of the frequency offset drift amount, the tunable laser 5020 may sequentially output a plurality of optical signals at a first preset wavelength or continuously output an optical signal at a second preset wavelength within a certain period of time, so as to detect the frequency offset drift amount of a certain target channel. It should be noted that the output wavelength range of the tunable laser 5020 at least includes a preset wavelength range corresponding to each channel in all channels of the WSS 51, so that the optical signal generator 502 can provide the optical signal with the corresponding wavelength required for detecting the frequency offset drift amount for any channel.

In another possible implementation manner, the optical signal generator 502 can output optical signals at least two different wavelengths at the same time, so that the processor 501 can simultaneously detect the frequency offset drift amounts of at least two target channels. The following description will take an example of a scenario in which the optical signal generator 502 can output optical signals at two different wavelengths at the same time.

Referring to fig. 15 together, fig. 15 is a schematic structural diagram of another frequency offset processing apparatus according to an embodiment of the present disclosure, and as shown in fig. 15, the optical signal generator 502 may include a tunable laser 5021, a tunable laser 5022, a modulation module 5023, a modulation module 5024, and a coupling and splitting module 5025. The tunable laser 5021 is connected to the processor 501 and the modulation module 5023. The tunable laser 5022 is connected to the processor 501 and the modulation module 5024. The modulation module 5023 and the modulation module 5024 are also connected to the coupling and splitting module 5025. The modulation module 5023 is configured to perform first optical modulation on an optical signal output by the tunable laser 5021, and send the optical signal after the first optical modulation to the coupling optical splitting module 5025. The modulation module 5024 is configured to perform second optical modulation on an optical signal output by the tunable laser 5022, and send the optical signal after the second optical modulation to the coupling optical splitting module 5025. The optical modulation may specifically be amplitude modulation, phase modulation, or the like of an optical signal, and the first optical modulation and the second optical modulation use different modulation parameters to distinguish the optical signals after the respective modulation. This allows the subsequent processor 501 to demodulate the optical power fed back by the photodetector 503 when receiving the optical power, so as to distinguish the optical power of the optical signal from the tunable laser 5021 and the optical power from the tunable laser 5022. Similarly, processor 501 may also demodulate the wavelength it receives feedback from wavelength meter 504 to distinguish the wavelength of the optical signal originating from tunable laser 5021 from the wavelength of the optical signal originating from tunable laser 5022. The coupling optical splitting module 5025 is configured to couple the optical signal after the first optical modulation and the optical signal after the second optical modulation into the same optical signal, and then transmit the optical signal to the input end of the WSS 51. The output wavelength range of the tunable laser 5021 (for convenience of distinction, the first output wavelength range will be used instead of the description below) at least includes a preset wavelength range corresponding to each channel in the first part of channels of the WSS 51. The output wavelength range of the tunable laser 5022 (for convenience of distinction, the second output wavelength range will be used instead of the description) at least includes a preset wavelength range corresponding to each of the second partial channels of the WSS 51 except for the first partial channel. This enables the optical signal generator 101 to output optical signals with different wavelengths simultaneously, so as to provide optical signals with corresponding wavelengths required for detection for any one of the target channels included in the first partial channel and any one of the target channels included in the second partial channel at the same time.

It is assumed that the processor 501 performs the detection of the frequency offset drift amount on the second target channel in the first partial channel and the third target channel in the second partial channel simultaneously in the above-mentioned detection manner two, where the second target channel corresponds to the second preset wavelength λ 3, and the third target channel corresponds to the second preset wavelength λ 4. In a specific implementation, the processor 501 may control the tunable laser 5021 to output an optical signal at a second preset wavelength λ 3 (for convenience of distinction, a sixth optical signal is used instead of the description below), and may also control the tunable laser 5022 to output an optical signal at a second preset wavelength λ 4 (for convenience of distinction, a seventh optical signal is used instead of the description below). The modulation module 5023 performs the first optical modulation on the sixth optical signal to obtain a first optically modulated sixth optical signal. The modulation module 5024 may perform a second optical modulation on the seventh optical signal to obtain a second optically modulated seventh optical signal. Then, the coupling optical splitting module 5025 may couple the sixth optical signal after the first optical modulation and the seventh optical signal after the second optical modulation to obtain an eighth optical signal, and transmit the eighth optical signal to the input end of the WSS 51. The eighth optical signal is changed into a sixth optical signal after the first optical modulation and a seventh optical signal after the second optical modulation through the wavelength selection of the WSS 51, and reaches the detection output end through the second target channel and the third target channel, respectively. Meanwhile, the photodetector 503 may measure optical powers of the optical signal input at the input end and the optical signal output at the detection output end, respectively, to obtain a second input power and a second output power corresponding to the eighth optical signal, and feed back the second input power and the second output power corresponding to the eighth optical signal to the processor 501. Then, the processor 501 may perform corresponding demodulation on the second input power and the second output power corresponding to the eighth optical signal, so as to obtain the second input power and the second output power of the sixth optical signal, and the second input power and the second output power of the seventh optical signal. The above operations are repeated until the processor 501 obtains the second insertion loss value of each second switching unit under the sixth optical signal and the second insertion loss value of each second switching unit under the seventh optical signal. Then, the processor 501 may determine the frequency offset offsets of the second target channel and the third target channel at the same time, and for the specific determination process, reference is made to the foregoing, and details are not repeated here.

In this implementation manner, the optical signal generator 502 can simultaneously satisfy the optical signals with different wavelengths in the process of detecting the frequency offset drift amount of at least two channels, so that the processor 501 can simultaneously detect the frequency offset drift amount of at least two channels, and the efficiency of detecting the frequency offset drift amount can be improved. In addition, in the implementation mode, the requirement on the output wavelength range of the laser included in the optical signal generator is relatively low, the cost of the frequency offset processing device can be further reduced, and the applicability of the low frequency offset processing device is improved.

In the embodiment of the present application, the frequency offset processing apparatus 50 first detects the frequency offset drift amount of each channel, and then performs frequency offset compensation on each channel based on the frequency offset drift amount of each channel. Because the frequency offset of each channel is compensated based on the frequency offset drift amount of each channel, and the frequency offset drift amount of each channel eliminates detection errors caused by factory frequency offset, the WSS 51 frequency offset compensation is reasonable and effective. Therefore, after frequency offset compensation, the frequency offset of each channel of the WSS 51 can reach or approach the frequency offset of the WSS 51 at the first time, so as to avoid the change of the frequency offset brought to the WSS 51 due to factors such as device aging, and the like, so that the performance of the WSS 51 can be maintained at the level of the first time, and the stability of the performance of the WSS 51 is ensured.

Referring to fig. 6 together, as shown in fig. 6, the present embodiment provides a frequency offset processing apparatus 50, which can be used to execute the frequency offset processing method described in the first embodiment. The processor 501, the optical signal generator 502, and the photodetector 503 included in the frequency offset processing apparatus 50 are electrically or optically connected to the WSS 51, respectively. In an example, the frequency offset processing apparatus 50 may be a complete device, and implement the method in the foregoing embodiments, for example, the complete device may include: the processor 501, the optical signal generator 502, the photodetector 503, and the like. In another example, the frequency offset processing apparatus may be a chip system or a processing system, and is applied in a complete device including the optical signal generator 502 and the photodetector 503 to control the complete device to implement the method in the foregoing embodiments, where the chip system or the processing system may include: the processor, optionally, also includes a computer-readable storage medium/memory.

In particular implementations, the processor 501 may be used to perform the control of the optical signal generator 502 and the photodetector 503 and the associated data processing operations involved in the methods described in fig. 7, 9, or 13. For example, the processor 501 may control the optical signal generator 502 to output optical signals at a plurality of first preset wavelengths or optical signals at a single second preset wavelength. The processor 501 may also control the photodetector 503 to obtain the input power and the output power of the WSS 51 at different first preset wavelengths, and the like. For a specific process, reference may be made to the method or steps executed by the processor 501 in the foregoing embodiments, and details are not described here.

Optionally, the computer-readable storage medium/memory stores programs, instructions and data for executing the technical solution of the present application. For example, the computer-readable storage medium/memory may contain instructions sufficient to allow frequency offset processing apparatus 50 to perform all of the functions described above in connection with processor 501 in the embodiments.

Alternatively, the computer-readable storage medium/memory may be an internal memory located inside the processor, or may be an external memory located outside the processor and coupled to the processor.

Optionally, please refer to fig. 11 together. As shown in fig. 11, the frequency offset processing apparatus 50 may further include a wavelength meter 504 electrically or optically connected to the processor 501 and the WSS, respectively. In a specific implementation, the processor 501 may control the wavelength meter 504 to detect the wavelength of the optical signal at the input port of the WSS 51, so as to obtain a first input detection wavelength corresponding to each first preset wavelength or a second input detection wavelength corresponding to each second switching unit. The processor 501 may determine the target filter spectrum corresponding to the first switching unit according to the multiple first input detection wavelengths and the first insertion loss value at each first preset wavelength, or may determine the frequency offset drift amount of the first target channel according to the average value of the first input detection wavelengths corresponding to each second switching unit and the wavelength corresponding to the target position, where the specific process may be referred to above, and is not described here again.

Optionally, please refer to fig. 15 together. As shown in fig. 15, the optical signal generator 502 in the frequency offset processing apparatus 50 may specifically include a tunable laser 5021, a tunable laser 5022, a modulation module 5023, a modulation module 5024, and a coupling and splitting module 5025. The processor 501 may control the tunable laser 5021, the tunable laser 5022, the modulation module 5023, the modulation module 5024, and the coupling and splitting module 5025, respectively, so that the optical signal generator 502 can output optical signals with different wavelengths simultaneously, thereby providing optical signals with corresponding wavelengths required for detection for at least two target channels simultaneously. For the specific process, reference is made to the above description, and the detailed description is omitted here.

It should be added that the Processor 501 in the frequency offset processing apparatus 50 may be a general-purpose Processor, such as a general-purpose Central Processing Unit (CPU), a Network Processor (NP), a microprocessor, or the like, or may be an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of the program according to the present application. The device can also be a Digital Signal Processor (DSP), a Field-Programmable Gate Array (FPGA), or other Programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The controller/processor can also be a combination of computing functions, e.g., comprising one or more microprocessors, DSPs, and microprocessors, among others. Processors typically perform logical and arithmetic operations based on program instructions stored within memory.

The computer-readable storage media/memories referred to above may also hold an operating system and other application programs. In particular, the program may include program code comprising computer operating instructions. More specifically, the memory may be a read-only memory (ROM), other types of static storage devices that store static information and instructions, a Random Access Memory (RAM), other types of dynamic storage devices that store information and instructions, a disk memory, or the like. The memory may be a combination of the above memory types. And the computer-readable storage medium/memory described above may be in the processor, may be external to the processor, or distributed across multiple entities including the processor or processing circuitry. The computer-readable storage medium/memory described above may be embodied in a computer program product. By way of example, a computer program product may include a computer-readable medium in packaging material.

Referring to fig. 16, fig. 16 is a schematic structural diagram of another frequency offset processing apparatus according to an embodiment of the present application. As shown in fig. 16, the frequency offset processing apparatus 160 may include a processing unit 1601, an optical signal generating unit 1602, and a photo-detecting unit 1603. The frequency offset processing apparatus 160 may be used to execute the control or data processing procedure related to the frequency offset processing method described in fig. 7, 9 or 13.

For example, the processing unit 1601 may be configured to control the optical signal generating unit 1602 and the photo-detecting unit 1603 to detect a frequency offset drift amount of each of one or more channels of the WSS 17. The processing unit 1601 is further configured to perform frequency offset compensation on each channel according to the frequency offset drift amount of each channel.

In an example, the processing unit 1601 is configured to determine one or more target channels from the one or more channels of the WSS 17 and determine a frequency offset drift amount of each of the one or more target channels, which are described in step S71 in this embodiment. The processing unit 1601 is further configured to perform the step of determining the frequency offset drift amount of each of the one or more channels of the WSS 17 according to the frequency offset drift amount of each target channel described in step S72 in this embodiment.

In another example, the WSS 17 includes a switching engine that includes a plurality of switching elements. The processing unit 1601 may be used to perform the process described in step S7101 in the embodiments to obtain the target filtered spectrum of the first switching unit. The processing unit 1601 is further configured to perform the process, which is described in step S7102, of determining a frequency offset drift amount of the first target channel according to the center wavelength of the target filter spectrum and the wavelength corresponding to the first switching unit at the first time. Here, the first target channel is any one of the one or more target channels.

In yet another example, as described in step S7101 in the embodiment, the processor 501 may control the optical signal generating unit 1602 to perform wavelength scanning on the first switching unit with at least one optical signal with a first preset wavelength. The processor 501 may further control the photo-detection unit 1603 to obtain a first input power and a first output power of the WSS 17 at the optical signal of each of the at least one first preset wavelength. The processing unit 1601 is further configured to determine a target filter spectrum of the first switching unit according to the first input power and the first output power of the WSS 17 under each optical signal with the first preset wavelength. Here, the target filtered spectrum includes a corresponding first insertion loss value of the first switching unit at each first preset wavelength, and the first insertion loss value of the first switching unit at any first preset wavelength is a difference value between a first output power and a first input power of the WSS 17 at an optical signal at any first preset wavelength.

In yet another example, as shown in step S7102 in the embodiment, the center wavelength of the target filtered spectrum is the first preset wavelength with the smallest absolute value of the first insertion loss value in each of the first preset wavelengths.

In another example, as described in step S7111 of the embodiment, the processing unit 1601 is further configured to obtain a target position of a light spot generated by the WSS switching engine by the optical signal at a second preset wavelength when the optical signal at the second preset wavelength passes through the first target channel. As described in step S7112 of the embodiment, the processing unit 1601 is further configured to determine a frequency offset drift amount of the first target channel according to the wavelength corresponding to the target location at the first time and the second preset wavelength. Here, the first target channel is any one of the one or more target channels.

In another example, the switch engine includes a plurality of switch units, and as described in step S7111 in the embodiment, the processing unit 1601 is further configured to determine a second insertion loss value of each of at least two second switch units of the at least two second switch units corresponding to the first target channel on the switch engine at the second preset wavelength, respectively. And determining the target position of a light spot generated by the optical signal under the second preset wavelength in the switching engine of the WSS 17 according to the second insertion loss value of each second switching unit under the second preset wavelength and the preset filter spectrum of each second switching unit at the first moment. Here, the preset filter spectrum of any second switching unit of the at least two switching units includes preset insertion loss values corresponding to a plurality of preset positions of the any second switching unit in the dispersion direction of the switching engine.

In another example, as described in step S7111 of the embodiment, the processor 501 is configured to control the photodetection unit 1603 to obtain the second input power and the second output power of any second switching unit when the optical signal with the second preset wavelength passes through the first target channel. The processing unit 1601 is further configured to determine a difference between a second input power and a second output power of the any second switching unit when the optical signal with the second preset wavelength passes through the first target channel, as a second insertion loss value of the any second switching unit at the second preset wavelength.

In another example, as described in step S7111 in this embodiment, the processing unit 1601 is further configured to determine, according to the preset filtered spectrum of each second switching unit at the first time, a preset insertion loss value set corresponding to each preset position in the plurality of preset positions. Here, the preset insertion loss value set corresponding to any preset position includes a preset insertion loss value corresponding to each second switching unit at any preset position. And determining a target position of a light spot generated on the switching engine by the optical signal under the second preset wavelength from the plurality of preset positions according to a second insertion loss value of each second switching unit under the second preset wavelength and a preset insertion loss value set corresponding to each preset position.

In another example, as described in step S7112 in the embodiment, the processing unit 1601 is further configured to determine, according to the preset insertion loss value set corresponding to each preset position, a first relative insertion loss value set corresponding to each preset position. Here, the first relative insertion loss value group corresponding to any one preset position includes a comparison result of the preset insertion loss values of any two second exchange units at the any one preset position. And determining a second relative insertion loss value set according to a second insertion loss value of each second exchange unit under the optical signal with the second preset wavelength. Here, the second relative insertion value group includes a result of comparing the second insertion values of any two second switching units. And determining a target relative insertion loss group matched with the second relative insertion loss group from the first relative insertion loss group corresponding to each preset position, and determining a preset position corresponding to the target relative insertion loss group as a target position of a light spot generated on the exchange engine by the optical signal under the second preset wavelength.

In yet another example, the target channel is a traffic channel of the WSS 17 through which no traffic optical signal passes, and/or a non-traffic channel of the WSS other than the traffic channel.

Further, please refer to fig. 17, wherein fig. 17 is a schematic structural diagram of another frequency offset processing apparatus provided in the present application. As shown in fig. 17, the frequency offset processing apparatus 17 further includes a wavelength detection unit 1604.

In one example, as described in the embodiments, the processing unit 1601 may control the first input detection wavelength of the optical signal at the input terminal of the WSS 17 when the wavelength detection unit detects that the optical signal of each first preset wavelength is input to the WSS 17. Then, the processing unit 1601 may determine a target filter spectrum according to the N2 first input detection wavelengths and the first insertion loss value at each first preset wavelength.

In another example, as described in the embodiment, the processing unit 1601 may obtain, through the wavelength detection unit 1604, the wavelength of the optical signal at the input port of the WSS 17 every time one second switching unit is turned on, so as to obtain the second input detection wavelength corresponding to each second switching unit. Then, the processing unit 1601 may calculate a wavelength average of a plurality of second input detection wavelengths corresponding to the plurality of second switching units, and determine a frequency offset drift amount of the first target channel according to a difference between a wavelength corresponding to a target position and the wavelength average.

Embodiments of the present application further provide a chip system, which includes a processor, configured to support the frequency offset processing apparatus to implement the functions involved in the foregoing embodiments, such as generating or processing data and/or information involved in the foregoing methods. In a possible design, the chip system may further include a memory, where the memory is used for program instructions and data necessary for a transmitting end or a receiving end, and when the processor executes the program instructions, the apparatus in which the chip system is installed is enabled to implement the frequency offset processing method in the foregoing embodiment. The chip system may be constituted by a chip, or may include a chip and other discrete devices.

Embodiments of the present application further provide a processor coupled to a memory, where the memory stores instructions that, when executed by the processor, cause the processor to perform the methods or functions described in the embodiments above with reference to the processor 501.

Embodiments of the present application also provide a computer program product containing instructions, which when executed on a computer, cause the computer to perform the methods or functions related to the processor 501 in the embodiments described above.

Embodiments of the present application also provide a computer-readable storage medium storing instructions that, when executed by a processor, cause the processor to perform the methods or functions described above with respect to the processor 501.

The embodiment of the present application further provides a frequency offset processing system, which includes at least one frequency offset processing apparatus and a WSS in the foregoing embodiments.

Those skilled in the art will recognize that in one or more of the examples described above, the functions described herein may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a general purpose or special purpose computer.

The above-mentioned embodiments, objects, technical solutions and advantages of the present application are further described in detail, it should be understood that the above-mentioned embodiments are only examples of the present application, and are not intended to limit the scope of the present application, and any modifications, equivalent substitutions, improvements and the like made on the basis of the technical solutions of the present application should be included in the scope of the present application.

Claims

1. A frequency offset processing method of a Wavelength Selective Switch (WSS), which is characterized by comprising the following steps:

determining a frequency offset drift amount of each of one or more channels of the WSS, wherein the frequency offset drift amount of any one of the one or more channels is used to indicate a difference degree between a frequency offset of the any one channel at a first time and a frequency offset of the any one channel at a second time, the first time and the second time being different times, and the first time being before the second time;

and performing frequency offset compensation on each channel according to the frequency offset drift amount of each channel.

2. The method of claim 1, wherein the determining an amount of frequency offset drift for each of the one or more channels of the WSS comprises:

determining one or more target channels from one or more channels of the WSS;

determining a frequency offset drift amount of each of the one or more target channels;

and determining the frequency offset drift amount of each channel in one or more channels of the WSS according to the frequency offset drift amount of each target channel.

3. The method of claim 2, wherein the WSS comprises a switching engine comprising a plurality of switching elements, and wherein determining the amount of frequency offset drift for each of the one or more target channels comprises:

acquiring a target filtering spectrum of a first switching unit, wherein the first switching unit is a switching unit corresponding to a first target channel on the switching engine;

determining the frequency offset drift amount of the first target channel according to the central wavelength of the target filtering spectrum and the wavelength corresponding to the first switching unit at the first time;

wherein the first target channel is any one of the one or more target channels.

4. The method of claim 3, wherein obtaining the target filtered spectrum of the first switching unit comprises:

controlling an optical signal generator to perform wavelength scanning on the first switching unit by using at least one optical signal with a first preset wavelength;

respectively acquiring first input power and first output power of the WSS under the optical signal of each first preset wavelength in the at least one first preset wavelength;

determining a target filter spectrum of the first switching unit according to the first input power and the first output power of the WSS under the optical signal with each first preset wavelength, wherein the target filter spectrum comprises a first insertion loss value of the first switching unit under each first preset wavelength, and the first insertion loss value of the first switching unit under any first preset wavelength is a difference value of the first output power and the first input power of the WSS under the optical signal with any first preset wavelength.

5. The method of claim 3, wherein the center wavelength of the target filtered spectrum is the first predetermined wavelength with the smallest absolute value of the first insertion loss value among the first predetermined wavelengths.

6. The method of claim 2, wherein the WSS comprises a switching engine, and wherein determining the amount of frequency offset drift for each of the one or more target channels comprises:

when an optical signal under a second preset wavelength passes through a first target channel, acquiring a target position of a light spot generated on the switching engine by the optical signal under the second preset wavelength;

determining the frequency offset drift amount of the first target channel according to the wavelength of the target position at the first moment and the second preset wavelength;

wherein the first target channel is any one of the one or more target channels.

7. The method of claim 6, wherein the switching engine comprises a plurality of switching units thereon, and the obtaining the target position of the optical spot generated on the WSS switching engine by the optical signal at the second preset wavelength comprises:

respectively determining a second insertion loss value of each of at least two second switching units corresponding to the first target channel on the switching engine under the second preset wavelength;

and determining the target position of a light spot generated on the switching engine by the optical signal under the second preset wavelength according to the second insertion loss value of each second switching unit under the second preset wavelength and the preset filter spectrum of each second switching unit at the first moment, wherein the preset filter spectrum of any second switching unit in the at least two switching units indicates the preset insertion loss values corresponding to a plurality of preset positions of the any second switching unit in the dispersion direction of the switching engine.

8. The method of claim 7, wherein the determining the target position of the optical spot generated by the WSS switching engine by the optical signal at the second preset wavelength according to the second insertion loss value of each second switching unit at the second preset wavelength and the preset filter spectrum of each second switching unit at the first time comprises;

determining a preset insertion loss value set corresponding to each preset position in the plurality of preset positions according to a preset filter spectrum of each second exchange unit at the first moment, wherein the preset insertion loss value set corresponding to any preset position comprises a preset insertion loss value corresponding to each second exchange unit at any preset position;

and determining a target position of a light spot generated on the switching engine by the optical signal under the second preset wavelength from the plurality of preset positions according to a second insertion loss value of each second switching unit under the second preset wavelength and a preset insertion loss value set corresponding to each preset position.

9. The method according to claim 8, wherein determining the target position of the optical spot generated by the WSS switching engine by the optical signal at the second preset wavelength from the plurality of preset positions according to the second insertion loss value of each second switching unit at the second preset wavelength and the preset insertion loss value sets corresponding to the plurality of preset positions comprises:

determining a first relative insertion loss value set corresponding to each preset position according to the preset insertion loss value set corresponding to each preset position, wherein the first relative insertion loss value set corresponding to any preset position comprises a comparison result of the preset insertion loss values of any two second exchange units in any preset position;

determining a second relative insertion loss value set according to a second insertion loss value of each second exchange unit under the optical signal with the second preset wavelength, wherein the second relative insertion loss value set comprises a comparison result of the second insertion loss values of any two second exchange units;

and determining a target relative insertion loss group matched with the second relative insertion loss group from the first relative insertion loss group corresponding to each preset position, and determining a preset position corresponding to the target relative insertion loss group as a target position of a light spot generated on the exchange engine by the optical signal under the second preset wavelength.

10. The method according to any of claims 2-9, wherein the target channel is a traffic channel of the WSS through which no traffic optical signal passes, and/or a non-traffic channel of the WSS other than the traffic channel.

11. A WSS frequency offset processing apparatus, comprising:

a processor, configured to determine a frequency offset drift amount of each of one or more channels of the WSS, where the frequency offset drift amount of any one of the one or more channels is used to indicate a degree of offset between a frequency offset of the any one channel at a first time and a frequency offset of the any one channel at a second time, where the first time and the second time are different times, and the first time is before the second time;

the processor is further configured to perform frequency offset compensation on each channel according to the frequency offset drift amount of each channel.

12. The frequency deviation processing apparatus of claim 11 wherein the processor is further configured to:

determining one or more target channels from one or more channels of the WSS;

determining a frequency offset drift amount of each target channel of the one or more target channels;

13. The frequency offset processing apparatus of claim 12 wherein said WSS comprises a switching engine, said switching engine comprising a plurality of switching elements;

the processor is configured to obtain a target filter spectrum of a first switching unit, where the first switching unit is a switching unit corresponding to a first target channel on the switching engine;

the processor is further configured to determine a frequency offset drift amount of the first target channel according to a center wavelength of the target filter spectrum and a wavelength corresponding to the first switching unit at the first time;

wherein the first target channel is any one of the one or more target channels.

14. The frequency offset processing apparatus of claim 13, wherein said frequency offset processing apparatus further comprises an optical signal generator and a photodetector;

the optical signal generator is used for performing wavelength scanning on the first switching unit by using at least one optical signal with a first preset wavelength;

the photodetector is used for acquiring first input power and first output power of the WSS under the optical signal of each first preset wavelength in the at least one first preset wavelength;

the processor is further configured to determine a target filter spectrum of the first switching unit according to first input power and first output power of the WSS under the optical signal of each first preset wavelength, where the target filter spectrum includes that the first switching unit is in a first insertion loss value corresponding to each first preset wavelength, and a first insertion loss value of the first switching unit under any first preset wavelength is a difference between first output power and first input power of the WSS under the optical signal of any first preset wavelength.

15. The frequency deviation processing apparatus of claim 13 wherein the center wavelength of the target filtered spectrum is the first predetermined wavelength with the smallest absolute value of the first insertion loss value among the first predetermined wavelengths.

16. The frequency deviation processing apparatus of claim 12 wherein the processor is further configured to:

when the optical signal under the second preset wavelength passes through the first target channel, acquiring the target position of a light spot generated by the optical signal under the second preset wavelength in the WSS switching engine;

wherein the first target channel is any one of the one or more target channels.

17. The frequency offset processing apparatus of claim 16 wherein said switching engine includes a plurality of switching elements thereon, said processor further configured to:

and determining the target position of a light spot generated by the WSS switching engine according to the second insertion loss value of each second switching unit at the second preset wavelength and the preset filter spectrum of each second switching unit at the first moment, wherein the preset filter spectrum of any second switching unit in the at least two switching units comprises preset insertion loss values corresponding to a plurality of preset positions of the any second switching unit in the dispersion direction of the switching engine.

18. The frequency deviation processing apparatus of claim 17 wherein said frequency deviation processing apparatus further comprises a photodetector;

the photodetector is configured to acquire a second input power and a second output power of any one of the second switching units when the optical signal with the second preset wavelength passes through the first target channel;

the processor is configured to determine a second insertion loss value of any one of the second switching units at the second preset wavelength according to a second input power and a second output power of the any one of the second switching units when the optical signal at the second preset wavelength passes through the first target channel.

19. The frequency deviation processing apparatus of claim 17 wherein the processor is further configured to:

20. The frequency deviation processing apparatus of claim 19, wherein the processor is further configured to:

21. The frequency offset processing apparatus of any of claims 12-20, wherein the target channel is a traffic channel of the WSS through which no traffic optical signal passes, and/or a non-traffic channel of the WSS other than the traffic channel.

22. A frequency offset processing system, comprising:

the frequency offset processing apparatus of any of claims 11-21;

and a WSS for passing optical signals at each first preset wavelength, or for passing optical signals at a second preset wavelength.