CN118282497A

CN118282497A - Apparatus, method and related device for monitoring rotation of polarization state of optical signal

Info

Publication number: CN118282497A
Application number: CN202211740959.XA
Authority: CN
Inventors: 单丽楠; 姚广浩; 忻海云; 唐进; 张晓光
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2022-12-30
Filing date: 2022-12-30
Publication date: 2024-07-02
Also published as: WO2024140977A1

Abstract

Disclosed are a RSOP device, a method and related equipment for monitoring optical signals, which belong to the technical field of optical communication. The device comprises: the device comprises a polarizing unit, a photoelectric conversion unit and a processing unit, wherein the polarizing unit is used for extracting linearly polarized light components of optical signals with first wavelength in a transmission link of an optical communication system; the photoelectric conversion unit is used for performing photoelectric conversion on the optical signal output by the polarizing unit to obtain an electric signal; the processing unit is configured to determine RSOP related information based on the electrical signal. The device can monitor the related information of RSOP when the RSOP speed of the optical signal is high.

Description

Apparatus, method and related device for monitoring rotation of polarization state of optical signal

Technical Field

The present application relates to the field of information security technology, and in particular, to an apparatus, method and related device for monitoring rotation (rotation of state of polarization, RSOP) of polarization states of optical signals.

Background

Transmission links in optical communication systems are subject to various risks, such as lightning strikes, mechanical vibrations, fiber extrusion, bending or breaking, which occur to reduce the stability of the transmission link, resulting in a reduced transmission quality. Since these risk events often occur with a change in polarization of the optical signal in the transmission link, i.e. RSOP, capturing of the risk event can be achieved by monitoring the optical signal RSOP.

In the related art, an equalizer based on a multiple-input multiple-output (multiple input multiple output, MIMO) equalization algorithm is generally provided in a coherent optical receiver. Based on the tap coefficient matrix of the equalizer, jones matrixes at different moments can be obtained. The jones matrix may be considered as the inverse of the polarized channel, with monitoring RSOP being done based on the jones matrix.

When the speed of RSOP is too high, the insufficient compensation capability of the MIMO equalization algorithm causes interruption of communication service, and the jones matrix cannot be acquired, so that RSOP cannot be monitored.

Disclosure of Invention

The application provides a device, a method and related equipment for monitoring an optical signal RSOP, which can monitor RSOP of the optical signal based on the optical signal in a transmission link.

In a first aspect, an apparatus for monitoring an optical signal RSOP is provided. The device comprises a polarizing unit, a photoelectric conversion unit and a processing unit. The polarizing unit is used for extracting linearly polarized light components of the optical signal of the first wavelength in the transmission link of the optical communication system. The photoelectric conversion unit is used for performing photoelectric conversion on the optical signal output by the polarizing unit to obtain an electric signal. The processing unit is configured to determine RSOP related information based on the electrical signal.

The device directly utilizes the optical signal of the first wavelength in the transmission link of the optical communication system to determine RSOP related information, does not need to use the electric domain parameters related to the equalizer in the coherent optical receiver, can monitor RSOP related information under the condition of high RSOP speed, and can timely find out the abnormality of the transmission link.

And the device is arranged at different positions in the optical communication system according to the requirement, so that the device can selectively monitor the whole transmission link from the transmitter to the receiver or monitor a section of transmission link from the transmitter to the receiver starting from the transmitter.

In some examples, the processing unit includes an envelope detector, an analog-to-digital converter, and a processor. The envelope detector is used for carrying out envelope detection on the electric signal to obtain an analog envelope signal. The analog-to-digital converter is configured to convert the analog envelope signal into a digital envelope signal. The processor is configured to determine the RSOP related information based on the digital envelope signal.

The analog envelope signal is extracted by the envelope detector, and then the analog-to-digital converter is used for analog-to-digital conversion of the analog envelope signal, so that the sampling rate of the analog-to-digital converter and the frequency requirement of the processor can be reduced. Since the cost of the analog-to-digital converter is positively correlated with the sampling rate, i.e. the higher the sampling rate of the analog-to-digital converter, the higher the cost of the analog-to-digital converter. Therefore, the requirement of the sampling rate of the analog-to-digital converter is reduced, which is beneficial to reducing the cost of the device. Similarly, the cost of the processor is positively correlated to the frequency of the processor, thus reducing the frequency requirements of the processor and also contributing to the cost of the device.

In other examples, the processing unit includes an analog-to-digital converter and a processor. The analog-to-digital converter is used for sampling the electric signal to obtain a sampling signal. The processor is used for acquiring a digital envelope signal based on the sampling signal; and determining the RSOP related information based on the digital envelope signal. The analog-digital converter and the processor are directly used for processing the electric signals output by the photoelectric conversion unit, and the processing unit contains fewer devices, so that the structure of the device is simplified.

In some examples, the polarizing unit is configured to extract a linearly polarized light component of the light signal. In this case, the polarizing unit may include a polarizing beam splitter or a polarizer. The photoelectric conversion circuit includes a Photodetector (PD) for connection to one output terminal of the polarizing unit.

Optionally, the photoelectric conversion circuit further comprises a direct current isolator and an amplifier. The DC isolator is used for extracting an alternating current component in the electric signal output by the PD, and the amplifier is used for amplifying the alternating current component output by the DC isolator and outputting the amplified alternating current component to the processing unit.

In other examples, the polarizing unit is configured to extract two orthogonal linearly polarized light components of the optical signal. At this time, the polarizing unit includes a polarizing beam splitter. Optionally, the photoelectric conversion circuit comprises a balanced photoelectric detector (balanced photodetector, BPD), or the photoelectric conversion circuit comprises two photoelectric detectors and a subtracting circuit, wherein two output ends of the two photoelectric detectors are respectively connected with two input ends of the subtracting circuit.

In the present application, the process of determining the RSOP related information by the aforementioned processor is referred to any one of the methods provided in the second aspect.

In a second aspect, a method of monitoring an optical signal RSOP is provided. At least part of the steps in the method may be implemented by a processor in an apparatus as provided in the first aspect. The method comprises the following steps: acquiring an electric signal, wherein the electric signal is obtained by performing photoelectric conversion on a linearly polarized light component of an optical signal with a first wavelength in a transmission link of an optical communication system; based on the electrical signals, relevant information is determined RSOP.

Based on the electrical signals, determining RSOP related information includes two ways:

Firstly, carrying out envelope detection on the electric signal to obtain an analog envelope signal; converting the analog envelope signal into a digital envelope signal; and finally, determining the related information of RSOP based on the digital envelope signal.

Firstly, sampling the electric signal to obtain a sampling signal; acquiring a digital envelope signal based on the sampling signal; and determining the RSOP related information based on the digital envelope signal.

In any possible implementation manner of the first aspect and the second aspect, the relevant information RSOP includes at least one of: RSOP speeds, a profile of RSOP speeds over a target period of time, and RSOP speed change times.

Optionally, the digital envelope signal comprises at least one sub-signal per unit time. The RSOP speed can be determined in the following manner: performing frequency domain transformation on a first sub-signal to obtain a frequency domain signal corresponding to the first sub-signal, wherein the first sub-signal is any one of the sub-signals in at least one unit time; and determining RSOP speeds of the first sub-signals in unit time based on frequencies corresponding to peak signals in the frequency domain signals. For example, the ratio of the frequency of the peak signal to 4pi is determined as RSOP speeds per unit time of the first sub-signal. By monitoring RSOP speed, anomalies occurring in the transmission link can be found out in time.

And, by determining RSOP the speed through frequency domain analysis, the requirement on the optical power input into the monitoring device can be reduced, so that the loss of the optical power in the transmission link caused by the monitoring device is small (for example, about 1 percent), and the influence on the transmission performance of the optical communication system is avoided.

Optionally, the target time period includes a plurality of unit times. The digital envelope signal comprises a plurality of sub-signals per unit time. The distribution spectrum of RSOP speeds in the target time period is used for indicating the corresponding relation between different RSOP speed intervals and the number of unit time in the target time period. The distribution spectrum of RSOP speeds over the target period may be determined in the following manner: a profile of RSOP speeds over the target time period is determined based on RSOP speeds over each unit time over the target time period. The change condition RSOP in the target time period can be determined through the distribution spectrum, and the change condition RSOP in the target time period can indirectly reflect the polarization change experienced by the optical fiber, so that the vibration condition (such as earthquake monitoring) or the temperature change condition and the like of the area where the optical fiber is located are monitored.

RSOP speed change times may be determined in the following manner: determining the variation of RSOP speeds in a set time period based on the digital envelope signal; time indication information for indicating a time when the variation exceeds the threshold value is determined. By determining RSOP the speed change time, a diagnosis can be made as to whether the fiber-bearing communication service is interrupted.

In a third aspect, a computer device is provided, the computer device comprising a processor and a memory; the memory is for storing a software program, and the processor is for causing the computer device to carry out the method of any one of the possible embodiments of the second aspect by executing the software program stored in the memory.

In a fourth aspect, there is provided a computer readable storage medium storing computer instructions that, when executed by a computer device, cause the computer device to perform the method of any one of the possible embodiments of the second aspect.

In a fifth aspect, an optical communication system is provided. The communication system comprises a first communication device, a second communication device and means for monitoring optical signals RSOP, wherein the first communication device and the second communication device are connected through a transmission link, and the means for monitoring optical signals RSOP are connected with the transmission link.

In a sixth aspect, there is provided a computer program product comprising instructions which, when run on a computer device, cause the computer device to perform the method of any one of the possible embodiments of the second aspect described above.

In a seventh aspect, a chip is provided, comprising a processor for calling from a memory and executing instructions stored in said memory, such that a communication device on which said chip is mounted performs the method of any one of the possible implementations of the second aspect described above.

In an eighth aspect, there is provided another chip comprising: the input interface, the output interface, the processor and the memory are connected through an internal connection path, the processor is used for executing the codes in the memory, and when the codes are executed, the processor is used for executing the method in any possible implementation mode of the second aspect.

Drawings

Fig. 1 is a schematic structural diagram of an optical communication system according to an embodiment of the present application;

FIG. 2 is a schematic diagram of an apparatus for monitoring RSOP optical signals according to an embodiment of the present application;

FIG. 3 is a schematic diagram of another apparatus for monitoring RSOP optical signals according to an embodiment of the present application;

FIG. 4 is a schematic diagram of another apparatus for monitoring RSOP optical signals according to an embodiment of the present application;

FIG. 5 is a schematic diagram of another apparatus for monitoring RSOP optical signals according to an embodiment of the present application;

FIG. 6 is a flow chart of a method RSOP for monitoring an optical signal according to an embodiment of the present application;

FIG. 7 is a block diagram of an apparatus for monitoring RSOP an optical signal provided by an embodiment of the present application;

fig. 8 is a schematic structural diagram of a computer device according to an embodiment of the present application.

Detailed Description

The embodiment of the application provides a device for monitoring an optical signal RSOP, which is hereinafter referred to as a monitoring device for short. The monitoring device may be used for RSOP monitoring a transmission link in an optical communication system. The application scenarios of the optical communication system include, but are not limited to, backbone network, metropolitan area convergence network, optical access network, optical fiber mobile backhaul network, optical fiber mobile fronthaul network, etc. The monitoring device is particularly suitable for RSOP monitoring transmission links of medium and long distances (for example, the distance of more than 80 km), and an optical communication system with the transmission links of the medium and long distances is generally applied to metropolitan area convergence networks, long-distance backbone networks and the like.

Fig. 1 is a schematic structural diagram of an optical communication system according to an embodiment of the present application. As shown in fig. 1, the optical communication system includes a first communication device 11, a second communication device 12, and a monitoring apparatus 14. The first communication device 11 is connected to the second communication device 12 via a transmission link 13. The transmission link 13 typically includes an optical transmission medium such as an optical fiber (for example, a Standard Single Mode Fiber (SSMF)), and may further include an optical device such as an optical amplifier (for example, a erbium doped fiber amplifier (erbium-doped fiber amplifier, EDFA)), and an optical connector, which is not limited by the embodiment of the present application.

Alternatively, the optical communication system may be a coherent optical communication system or a direct-alignment optical communication system. The monitoring device 14 can monitor RSOP whether a coherent modulated signal or an intensity modulated signal is transmitted in the transmission link.

To increase the capacity of the optical communication system, the optical communication system may be a wavelength division multiplexing (WAVELENGTH DIVISION MULTIPLEXING, WDM) system. In WDM systems, the optical signals in the transmission link are WDM signals.

In some examples, the monitoring device 14 may be integrated in a communication apparatus. For example, as shown in part (a) of fig. 1, the monitoring means 14 may be integrated within the receiver 121 of the second communication device 12. As another example, as shown in part (b) of fig. 1, the monitoring device 14 is integrated in the second communication apparatus 12 and is disposed outside the receiver 121. I.e. the monitoring means 14 and the receiver 121 are two separate functional modules in the second communication device 12. The monitoring means 14 in parts (a) and (b) of fig. 1 may monitor the entire transmission link 13 from the transmitter of the first communication device 11 to the receiver of the second communication device 12.

In other examples, the monitoring device 14 may be provided independently. For example, as shown in part (c) of fig. 1, the monitoring device 14 is a device independent of the first communication apparatus 11 and the second communication apparatus 12, and the monitoring device 14 is connected to the intermediate section of the transmission link 13, for example, through the splitter 151 and the filter 15 b. The optical splitter splits off a part of the WDM signal in the transmission link 13 and feeds it to the monitoring device 14 after filtering by a filter. The monitoring means 14 may be arranged at a site between the first communication device 11 and the second communication device 12, for example. The monitoring means 14 in part (c) of fig. 1 may monitor the transmission link 13 between the transmitter of the first communication device 11 and the connection of the monitoring means 14.

The monitoring device 14 can be hung on a transmission link in an externally-hung manner, and the existing structure in the communication equipment is not required to be modified, so that the monitoring device is easy to realize.

The structure of the monitoring device 14 and the process of performing RSOP monitoring are described in detail below.

Fig. 2 is a schematic structural diagram of an apparatus for monitoring RSOP optical signals according to an embodiment of the present application. As shown in fig. 2, the monitoring device 14 includes a polarizing unit 21, a photoelectric conversion unit 22, and a processing unit 23. The polarizing unit 21 is used for extracting a linearly polarized light component of an optical signal of a first wavelength in a transmission link of an optical communication system. The photoelectric conversion unit 22 is configured to photoelectrically convert the optical signal output by the polarizing unit to obtain an electrical signal. The processing unit 23 is configured to determine RSOP the relevant information based on the electrical signal.

Illustratively, the input of the polarizing unit 21 is configured to receive the optical signal of the first wavelength, and the output of the polarizing unit 21 is configured to output a linearly polarized light component of the optical signal of the first wavelength. Alternatively, the polarizing unit 21 includes a polarizer (may also be referred to as a polarizer) 21a.

The photoelectric conversion unit 22 includes a photodetector 221 for converting the linearly polarized light component into an electric signal, for example. Optionally, the photodetector 221 includes, but is not limited to, a photodiode or photomultiplier tube, or the like.

Optionally, the photodetector 221 further comprises a dc isolation device 222. The input terminal of the dc isolation device 222 is connected to the output terminal of the photodetector device 221, and is used for removing the dc component from the electrical signal and outputting the ac component from the electrical signal. The dc isolation arrangement 222 includes, but is not limited to, a capacitor or the like.

Since the ac component in the electrical signal output by the photodetector 221 is weak, the relevant information of RSOP determined by the processing unit 23 directly based on the ac component may not be accurate enough, and thus, in some examples, the photoelectric conversion unit 22 may further include an amplifier 223, where an input end of the amplifier 223 is connected to an output end of the dc isolation device 222, so as to amplify the ac component output by the dc isolation device 222. Accordingly, the processing unit 23 determines RSOP related information based on the amplified ac component to improve accuracy of the determined related information.

Optionally, the amplifier 223 includes, but is not limited to, a trans-IMPEDANCE AMPLIFIER (TIA) or the like.

In some examples, the processing unit 23 includes an envelope detector 231, an ADC232, and a processor 233. The envelope detector 231 is configured to perform envelope detection on the electrical signal output by the photoelectric conversion unit 22, so as to obtain an analog envelope signal. The analog envelope signal may be referred to as a Relative Intensity Error (RIE) signal. The ADC232 is used to convert the analog envelope signal to a digital envelope signal. The processor 233 is configured to determine RSOP the relevant information based on the digital envelope signal.

Alternatively, in other examples, the processing unit 23 does not include the envelope detector 231, but includes the ADC232 and the processor 233. The input end of the ADC232 is connected to the output end of the photoelectric conversion unit, and the input end of the ADC232 is connected to the input end of the processor 233. In this case, the ADC232 is configured to sample the electrical signal to obtain a sampled signal. The processor 233 is configured to obtain a digital envelope signal based on the sampling signal; and determining RSOP related information based on the digital envelope signal.

The analog-digital converter and the processor are directly used for processing the electric signals output by the photoelectric conversion unit, and the processing unit contains fewer devices, so that the structure of the device is simplified.

In the embodiment of the present application, the polarization unit 21 outputs the linearly polarized light component of the optical signal of the first wavelength, which is equivalent to projecting the polarization state of the optical signal of the first wavelength on the poincare sphere with respect to the eigenstate of the polarization unit. Wherein the eigenstates of the polarizer unit 21 are identical to the polarization states of the linearly polarized light components output by the polarizer unit. The linearly polarized light component is subjected to photoelectric conversion to obtain an electric signal, and a digital envelope signal obtained based on the electric signal carries RSOP rotation angle information and can be called as a characteristic parameter. The amplitude of the digital envelope signal is proportional to the sine of the RSOP rotation angle, i.e. the amplitude of the digital envelope signal is proportional to the sine of the aforementioned projection angle, so that the amplitude variation of the digital envelope signal can reflect the variation of the RSOP rotation angle (i.e. the RSOP rotation speed), in particular, the amplitude variation period of the digital envelope signal can reflect the variation period of the RSOP rotation angle.

Optionally, the processor 233 includes, but is not limited to, a digital processor (DIGITAL SIGNAL processes, DSP), (field programmable GATE ARRAY, FPGA), or a single chip microcomputer, etc. to implement digital signal processing functions.

The processor 233 determines the relevant content of the relevant information RSOP based on the digital envelope signal, see method embodiments hereinafter, and detailed descriptions are omitted here.

In the embodiment of the present application, in order to ensure the normal operation of the device 14, the operation bandwidth of the PD221, the operation bandwidth of the amplifier 223, and the output bandwidth of the envelope detector 231 all need to be greater than the maximum value of RSOP rotation speeds.

Optionally, the apparatus may further comprise a light splitting unit for splitting the optical signal of the first wavelength from the transmission link. The input end of the light splitting unit is connected with the transmission link, and one output end of the light splitting unit is used for outputting the optical signal of the first wavelength.

In some examples, the light splitting unit includes a light splitter and a filter. The optical splitter comprises an input end and two output ends, wherein the input end and the output end of the optical splitter are connected in a transmission link, and the other output end of the optical splitter is connected with the input end of the filter. The output of the filter is connected to the input of the polarising element 21. The optical splitter is used for dividing optical signals transmitted in the transmission link into two paths, one path of the optical signals is continuously transmitted along the transmission link, and the other path of the optical signals is output to the filter. The filter is used to filter out the optical signal of the second wavelength and to emit the optical signal of the first wavelength to the polarizing unit 21. Here, the optical signal of the second wavelength is an optical signal of other wavelengths than the optical signal of the first wavelength among the optical signals transmitted by the transmission link.

It should be noted that when the apparatus is integrated in a communication device, the apparatus may not include a spectroscopic unit. The wavelength division multiplexing device in the communication device can be used to realize the demultiplexing of the optical signals with multiple wavelengths, so as to obtain the optical signal with the first wavelength, and the optical splitter in the communication device is used to split the optical signal with the first wavelength into two paths, one path is output to the receiver or the receiving module in the receiver, and the other path is output to the polarizing unit 21.

Alternatively, the splitting ratio of the splitter may be 99:1 to 97:3. Wherein a small fraction of the power of the optical signal is split for RSOP monitoring to avoid introducing large optical power losses to the optical communication system.

The device directly utilizes the optical signal of the first wavelength in the transmission link of the optical communication system to determine RSOP related information, does not need to use the electric domain parameters related to the equalizer in the coherent optical receiver, can monitor RSOP related information under the condition of high RSOP speed, and can timely find out the abnormality of the transmission link. And, adopt single PD to carry out photoelectric conversion, be favorable to reducing the consumption of this device. In addition, the device has a small number of devices, which is beneficial to reducing the cost and the volume of the device.

Fig. 3 is a schematic structural diagram of another apparatus for monitoring RSOP optical signals according to an embodiment of the present application. The device 14 in fig. 3 differs from the device 14 in fig. 2 in that the polarizing unit 21 comprises a polarizing beam splitter (polarization beam splitter, PBS) 21b. The PBS21b is used to split the optical signal at the first wavelength into two orthogonal linearly polarized light components. Here, orthogonal means that the linear polarization direction of the optical signal is perpendicular. One of the linearly polarized light components is an optical signal in a transverse electric field (TRANSVERSE ELECTRIC, TE) mode, and the other is an optical signal in a transverse magnetic field (TRANSVERSE MAGNETIC, TM) mode.

One of the two linearly polarized light components is output to the photoelectric conversion unit 22 for RSOP monitoring. The other of the two linearly polarized light components may be empty or may be used to monitor the optical power of the optical signal of the first wavelength separated from the transmission link, etc., according to which the working state of the device in the optical splitting unit may be monitored, so as to improve the reliability of the operation of the monitoring device 14.

Fig. 4 is a schematic structural diagram of another apparatus for monitoring RSOP optical signals according to an embodiment of the present application. The device 14 in fig. 4 differs from the device 14 in fig. 3 in that the structure of the photoelectric conversion unit 22 is different.

As shown in fig. 4, the photoelectric conversion unit 22 includes a BPD221 a. The BPD221a has two input terminals and one output terminal. The two inputs of BPD221a are respectively configured to receive two orthogonal linearly polarized light components output from PBS 21 b. The BPD221a is configured to photoelectrically convert the received two linearly polarized light components to obtain an electrical signal, and output the electrical signal from an output terminal of the BPD221 a. The electrical signal output by the BPD221a is the difference in the intensities of the two linearly polarized light components.

The BPD comprises two sub PDs, and the output electrical wiring lengths of the two sub PDs are matched, so that the BPD has the function of a subtracting circuit, namely, the direct current part in the electrical signal output by the two sub PDs can be removed. In addition, because the alternating current components of the electric signals corresponding to the two paths of linearly polarized light components are opposite, the BPD can have the functions of direct current isolation and signal strength increase, is beneficial to improving the contrast of the digital envelope signal (even the amplitude change of the digital envelope signal is more obvious), and improves the monitoring performance of the device. Further, the BPD has high detection sensitivity, and photoelectric conversion of the linearly polarized light component of the optical signal of the first wavelength can be completed when the optical power of the optical signal of the first wavelength is small.

In order to improve the quality of the electrical signal, the photoelectric conversion unit 22 further includes an amplifier 223, and an input terminal of the amplifier 223 is connected to an output terminal of the BPD 221a, for amplifying the electrical signal output from the BPD 221 a.

In the embodiment of the present application, in order to ensure the normal operation of the device 14, the operation bandwidth of the BPD221a and the operation bandwidth of the amplifier 223 are both required to be greater than the maximum value of RSOP rpm.

Fig. 5 is a schematic structural diagram of another apparatus for monitoring RSOP optical signals according to an embodiment of the present application. The device 14 in fig. 5 differs from the device 14 in fig. 4 in that the structure of the photoelectric conversion unit 22 is different.

As shown in fig. 5, the BPD 221a in fig. 4 is replaced by two PDs 221 and a subtracting circuit 224. The two PDs 221 are respectively for converting two linearly polarized light components into electric signals. The two input terminals of the subtracting circuit 224 are respectively connected to the output terminals of the two PDs 221, and are used for subtracting the electric signals output by the two PDs 221 to cancel the dc portion in the two electric signals and output the ac portion.

The use of two PDs is less costly than the use of a BPD compared to the embodiment shown in fig. 4. Compared with the embodiment shown in fig. 1 and 2, the subtracting circuit 224 can amplify the amplitude of the electric signal output by the photoelectric conversion device by one time, which is beneficial to improving the contrast of the digital envelope signal and improving the monitoring performance of the device.

The present application does not limit the configuration of the subtracting circuit 224 as long as it can function to cancel direct current.

Fig. 6 is a flow chart of a method for monitoring RSOP an optical signal according to an embodiment of the present application. As shown in fig. 6, the method includes the following steps.

Step 601: an electrical signal is obtained by photoelectrically converting a linearly polarized light component of an optical signal of a first wavelength in a transmission link of an optical communication system.

Step 602: based on the electrical signals, RSOP related information is determined.

In an embodiment of the present application, the related information RSOP includes at least one of the following: RSOP speeds, a profile of RSOP speeds over a target period of time, and RSOP speed change times.

In some examples, the relevant information for RSOP includes RSOP speed. By monitoring RSOP the speed, it can be determined whether an anomaly exists in the transmission link based on RSOP speed. For example, when RSOP speeds are greater than a speed threshold, it is determined that an anomaly exists in the transmission link. The speed threshold may be set according to actual needs, and may be above 100krad/s, for example. For example 100krad/s, etc.

In other examples, the relevant information RSOP includes a profile of RSOP speeds over the target period of time. The change condition RSOP in the target time period can be determined through the distribution spectrum, and the change condition RSOP in the target time period can indirectly reflect the polarization change experienced by the optical fiber, so that the vibration condition (such as earthquake monitoring) or the temperature change condition and the like of the area where the optical fiber is located are monitored.

In still other examples, the relevant information of RSOP includes RSOP speed change time. By determining RSOP the speed change time, a diagnosis can be made as to whether the communication traffic carried by the optical fiber is interrupted.

In still other examples, the relevant information for RSOP includes any two of RSOP speed, a profile of RSOP speed over a target time period, and RSOP speed change time, or the relevant information for RSOP includes RSOP speed, a profile of RSOP speed over a target time period, and RSOP speed change time. By monitoring the various RSOP related information simultaneously, RSOP in the transmission link can be monitored more comprehensively.

Alternatively, this step 202 may be implemented in either of two ways:

Firstly, carrying out envelope detection on an electric signal to obtain an analog envelope signal; converting the analog envelope signal into a digital envelope signal; finally, based on the digital envelope signal, the relevant information is determined RSOP.

Firstly, sampling an electric signal to obtain a sampling signal; acquiring a digital envelope signal based on the sampling signal; and determining RSOP related information based on the digital envelope signal.

Since the related information RSOP is time-varying, the related information RSOP can be determined at a granularity of a unit time. The length of the unit time may be set according to actual needs, and may be in the order of μs, for example. For example, 0.1. Mu.s to 3. Mu.s. In some examples, the length of the unit time may be 1 μs.

In an embodiment of the application the digital envelope signal comprises at least one sub-signal per unit time.

When the relevant information of RSOP includes RSOP speed, determining the relevant information of RSOP based on the digital envelope signal includes: the method comprises the steps of performing frequency domain transformation on a first sub-signal to obtain a frequency domain signal corresponding to the first sub-signal, wherein the first sub-signal is any one of sub-signals in at least one unit time; and secondly, determining RSOP speeds of the first sub-signals in unit time based on frequencies corresponding to peak signals in the frequency domain signals. For example, the ratio of the frequency of the peak signal to 4pi is determined as RSOP speeds per unit time of the first sub-signal.

In this first step, the first sub-signal may be subjected to a frequency domain transformation using an algorithm such as a fast fourier transform (fast Fourier transform, FFT) or a wavelet transform.

In the embodiment of the application, a distribution spectrum of RSOP speeds in the target time period is used for indicating the corresponding relation between different RSOP speed intervals and the number of unit time in the target time period. The target time period includes a plurality of unit times. The distribution spectrum includes at least two RSOP speed intervals. Based on the distribution spectrum, the number of unit time corresponding to each RSOP speed interval in the target time period can be determined, so that the distribution of RSOP speeds in the target time period can be determined.

Alternatively, the distribution spectrum may be presented in the form of a list (e.g., table one) or a graph.

Table I, distribution spectrum of RSOP speeds in target time period

Numbering device	Speed interval	Number of units of time
			1	[V0,V1)	n1
2	[V1,V2)	n2
			……	……	……
N	[VN-1,VN]	nN

In table one, the sum of n1, n2 … … nN is equal to the total number of units of time in the target period.

When the relevant information RSOP includes a distribution spectrum of RSOP speeds over the target time period, determining RSOP the relevant information based on the digital envelope signal includes: a distribution spectrum of rotational speeds of the deflected states in the target time period is determined based on RSOP speeds in each unit time in the target time period. For example, the number of unit time corresponding to the speed interval RSOP may be counted based on the speed interval RSOP to which the speed RSOP belongs in each unit time in the target time period, so as to obtain the distribution spectrum.

In the embodiment of the application, RSOP speed change time is used for indicating the time when the RSOP speed is suddenly changed or is changed drastically. When the relevant information RSOP includes RSOP speed change time, determining the relevant information of RSOP based on the digital envelope signal includes: the method comprises the steps of firstly, determining the variation of RSOP speeds in a set duration based on a digital envelope signal; and secondly, determining time indication information, wherein the time indication information is used for indicating the time when the variation exceeds the threshold value.

In the embodiment of the application, the requirement on the optical power input into the monitoring device can be reduced by determining the related information RSOP through frequency domain analysis, so that the loss of the optical power in the transmission link caused by the monitoring device is smaller (for example, about 1 percent) and the influence on the transmission performance of the optical communication system is avoided.

Fig. 7 is a schematic structural diagram of an apparatus for monitoring RSOP optical signals according to an exemplary embodiment of the present application. The apparatus may be implemented as part or all of an apparatus by software, hardware, or a combination of both. The device provided by the embodiment of the application can realize the flow of the embodiment of the application shown in fig. 6. As shown in fig. 7, the apparatus 700 includes: an acquisition module 701 and a determination module 702. The acquisition module 701 is configured to acquire an electrical signal, where the electrical signal is obtained by performing photoelectric conversion on a linearly polarized light component of an optical signal of a first wavelength in a transmission link of an optical communication system. The determining module 702 is configured to determine RSOP related information based on the electrical signal.

In some examples, the determination module 702 includes: an envelope detection submodule 7021, a conversion submodule 7022 and a determination submodule 7023. The envelope detection sub-module 7021 is configured to perform envelope detection on the electrical signal, so as to obtain an analog envelope signal. The conversion sub-module 7022 is used to convert the analog envelope signal into a digital envelope signal. The determining sub-module 7023 is configured to determine RSOP relevant information based on the digital envelope signal.

In other examples, the determination module 702 includes a sampling sub-module, an acquisition sub-module, and a determination sub-module. The sampling submodule is used for sampling the electric signal to obtain a sampling signal. The acquisition submodule is used for acquiring a digital envelope signal based on the sampling signal. The determining sub-module is configured to determine RSOP relevant information based on the digital envelope signal.

Optionally, the digital envelope signal comprises at least one sub-signal per unit time. The determining sub-module 7023 is configured to perform frequency domain transformation on a first sub-signal to obtain a frequency domain signal corresponding to the first sub-signal, where the first sub-signal is any one of sub-signals in at least one unit time; and determining RSOP speeds in unit time of the first sub-signals based on frequencies corresponding to peak signals in the frequency domain signals.

Optionally, the digital envelope signal comprises a plurality of sub-signals per unit time. The determination sub-module 7023 is configured to determine a distribution spectrum of rotational speeds of the deflected state over a target time period based on RSOP speeds over a plurality of unit times, the target time period including the plurality of unit times. The distribution spectrum is used for indicating the corresponding relation between different RSOP speed intervals and the number of unit time in the target time period.

Optionally, the determining submodule 7023 is configured to determine an amount of change in the speed RSOP in the set duration based on the digital envelope signal; time indication information for indicating a time when the variation exceeds the threshold value is determined.

It should be noted that: when the device for monitoring RSOP of an optical signal provided in the foregoing embodiment performs signal processing, only the division of the above functional modules is used for illustration, and in practical application, the above functional allocation may be performed by different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. In addition, the device for monitoring RSOP of the optical signal provided in the above embodiment and the method embodiment for monitoring RSOP of the optical signal belong to the same concept, and the specific implementation process of the device is detailed in the method embodiment, which is not repeated here.

The division of the modules in the embodiments of the present application is schematically shown as only one logic function division, and another division manner may be adopted in actual implementation, and in addition, each functional module in each embodiment of the present application may be integrated in one processor, or may exist alone physically, or two or more modules may be integrated into one module. The integrated modules may be implemented in hardware or in software functional modules.

The integrated module, if implemented in the form of a software functional module and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on this understanding, the technical solution of the present application may be embodied essentially or partly in the form of a software product or all or part of the technical solution, which is stored in a storage medium, and includes several instructions for causing a terminal device (which may be a personal computer, a mobile phone, or a communication device, etc.) or a processor (processor) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a read-only memory (ROM), a random access memory (random access memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

The embodiment of the application also provides a computer device, which can be the processing unit of the device in fig. 2 to 5. Fig. 8 provides an exemplary diagram of one possible architecture for a computer device 800.

Computer device 800 includes memory 801, processor 802, communication interface 803, and bus 804. Wherein the memory 801, the processor 802 and the communication interface 803 are communicatively connected to each other through a bus 804.

The memory 801 may be a ROM, static storage device, dynamic storage device, or RAM. The memory 801 may store a program, and when the program stored in the memory 801 is executed by the processor 802, the processor 802 and the communication interface 803 are used to perform a device access method. The memory 801 may also store data sets such as: a portion of the memory resources in the memory 801 are divided into a data storage module for storing digital envelope signals, etc.

The processor 802 may employ a general-purpose CPU, microprocessor, application-specific integrated circuit (ASIC), graphics processor (graphics processing unit, GPU), or one or more integrated circuits.

The processor 802 may also be an integrated circuit chip with signal processing capabilities. In implementation, some or all of the functions of the signal processing apparatus of the present application may be performed by integrated logic circuits of hardware in the processor 802 or by instructions in the form of software. The processor 802 described above may also be a general purpose processor, a digital signal processor (DIGITAL SIGNAL drocessing, DSP), an ASIC, an off-the-shelf programmable gate array (field programmable GATE ARRAY, FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware components. The methods disclosed in the above embodiments of the present application may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present application may be embodied directly in the execution of a hardware decoding processor, or in the execution of a combination of hardware and software modules in a decoding processor. The software modules may be located in a random access memory, flash memory, read only memory, programmable read only memory, or electrically erasable programmable memory, registers, etc. as well known in the art. The storage medium is located in the memory 801, and the processor 802 reads information in the memory 801, and in combination with its hardware, performs part of the functions of the key generation apparatus of the embodiment of the present application.

Communication interface 803 enables communication between computer device 800 and other devices or communication networks using a transceiver module such as, but not limited to, a transceiver. For example, a received sampled signal, a digital envelope signal, or the like may be acquired through the communication interface 803.

Bus 804 may include a path for transferring information between various components of computer device 800 (e.g., memory 801, processor 802, communication interface 803).

The descriptions of the processes corresponding to the drawings have emphasis, and the descriptions of other processes may be referred to for the parts of a certain process that are not described in detail.

In an embodiment of the present application, there is further provided a computer readable storage medium, where computer instructions are stored, which when executed by a computer device, cause the computer device to perform the above-provided method for monitoring an optical signal RSOP.

In an embodiment of the application, there is also provided a computer program product comprising instructions which, when run on a computer device, cause the computer device to perform the above-provided method for monitoring an optical signal RSOP.

In an embodiment of the present application, a chip is further provided for executing the method for monitoring an optical signal RSOP shown in fig. 6.

Unless defined otherwise, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The terms "first," "second," "third," and the like in the description and in the claims, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. Likewise, the terms "a" or "an" and the like do not denote a limitation of quantity, but rather denote the presence of at least one. The word "comprising" and the like means that elements or items appearing before "comprising" are encompassed by the element or item listed after "comprising" and equivalents thereof, and that other elements or items are not excluded.

The foregoing description of the preferred embodiment of the application is not intended to limit the application to the precise form disclosed, and any such modifications, equivalents, and alternatives falling within the spirit and scope of the application are intended to be included within the scope of the application.

Claims

1. An apparatus for monitoring rotation of a polarization state of an optical signal, characterized in that the apparatus comprises a polarizing unit, a photoelectric conversion unit and a processing unit,

The polarization unit is used for extracting linear polarized light components of the optical signals with the first wavelength in a transmission link of the optical communication system;

The photoelectric conversion unit is used for performing photoelectric conversion on the optical signal output by the polarizing unit to obtain an electric signal;

the processing unit is used for determining the rotation related information of the polarization state based on the electric signals.

2. The apparatus of claim 1, wherein the processing unit comprises an envelope detector, an analog-to-digital converter, and a processor,

The envelope detector is used for carrying out envelope detection on the electric signal to obtain an analog envelope signal;

the analog-to-digital converter is used for converting the analog envelope signal into a digital envelope signal;

the processor is configured to determine information about a rotation of the polarization state based on the digital envelope signal.

3. The apparatus of claim 1, wherein the processing unit comprises an analog-to-digital converter and a processor,

The analog-to-digital converter is used for sampling the electric signal to obtain a sampling signal;

The processor is used for acquiring a digital envelope signal based on the sampling signal; and determining information about the rotation of the polarization state based on the digital envelope signal.

4. A device according to claim 2 or 3, characterized in that the digital envelope signal comprises at least one sub-signal per unit time;

the processor is configured to perform frequency domain transformation on a first sub-signal to obtain a frequency domain signal corresponding to the first sub-signal, where the first sub-signal is any one of the sub-signals in the at least one unit time;

and determining the rotation speed of the polarization state of the first sub-signal in unit time based on the frequency corresponding to the peak signal in the frequency domain signal.

5. The apparatus of claim 4, wherein the digital envelope signal comprises a plurality of sub-signals per unit time;

the processor is further configured to determine a distribution spectrum of rotational speeds of the deflected state over a target time period based on the rotational speeds of the polarized states over the plurality of unit times, the target time period including the plurality of unit times;

The distribution spectrum is used for indicating the corresponding relation between the rotation speed intervals of different polarization states and the number of unit time in the target time period.

6. The apparatus of claim 4 or 5, wherein the processor is further configured to determine an amount of change in rotational speed of the polarization state for a set period of time based on the digital envelope signal; and determining time indication information, wherein the time indication information is used for indicating the time when the variation exceeds a threshold value.

7. The device of any one of claims 1 to 6, wherein the polarizing unit comprises a polarizing beam splitter or a polarizer.

8. The apparatus according to any one of claims 1 to 7, wherein the polarizing unit is configured to extract a linearly polarized light component of the optical signal, and the photoelectric conversion circuit includes a photodetector;

Or the polarizing unit is used for extracting two orthogonal linearly polarized light components in the optical signal, and the photoelectric conversion circuit comprises: the balance photoelectric detector, or two photoelectric detectors and subtracting circuit, two output ends of two photoelectric detectors are connected with two input ends of subtracting circuit respectively.

9. A method of monitoring rotation of a polarization state of an optical signal, the method comprising:

acquiring an electric signal, wherein the electric signal is obtained by performing photoelectric conversion on a linearly polarized light component of an optical signal with a first wavelength in a transmission link of an optical communication system;

based on the electrical signals, information about the rotation of the polarization state is determined.

10. The method of claim 9, wherein the determining information about the rotation of the polarization state based on the electrical signal comprises:

performing envelope detection on the electric signal to obtain an analog envelope signal;

Converting the analog envelope signal into a digital envelope signal; and

Based on the digital envelope signal, information about the rotation of the polarization state is determined.

11. The method of claim 9, wherein the determining information about the rotation of the polarization state based on the electrical signal comprises:

sampling the electric signal to obtain a sampling signal;

Acquiring a digital envelope signal based on the sampling signal; and

12. The method according to claim 10 or 11, wherein the digital envelope signal comprises at least one sub-signal per unit time;

Said determining information about the rotation of said polarization state based on said digital envelope signal comprises:

Performing frequency domain transformation on a first sub-signal to obtain a frequency domain signal corresponding to the first sub-signal, wherein the first sub-signal is any one of the sub-signals in at least one unit time;

13. The method of claim 12, wherein the digital envelope signal comprises a plurality of sub-signals per unit time;

the determining the rotation related information of the polarization state based on the digital envelope signal further comprises:

determining a distribution spectrum of rotational speeds of the deflected state in a target time period based on the rotational speeds of the polarized states in the plurality of unit times, the target time period including the plurality of unit times;

14. The method according to claim 12 or 13, wherein said determining information about the rotation of the polarization state based on the digital envelope signal further comprises:

Determining the variation of the rotation speed of the polarization state in a set time period based on the digital envelope signal;

and determining time indication information, wherein the time indication information is used for indicating the time when the variation exceeds a threshold value.

15. An optical communication system comprising a first communication device, a second communication device and means for monitoring an optical signal RSOP according to any one of claims 1 to 8, the first communication device and the second communication device being connected by a transmission link, the means for monitoring an optical signal RSOP being connected to the transmission link.

16. A computer device, the computer device comprising a processor and a memory; the memory is used for storing a software program, and the processor is used for enabling the computer device to realize the method according to any one of claims 9 to 14 by executing the software program stored in the memory.

17. A computer readable storage medium storing computer instructions which, when executed by a computer device, cause the computer device to perform the method of any one of claims 9 to 14.