CN115622618A

CN115622618A - Method and apparatus for optical fiber measurement

Info

Publication number: CN115622618A
Application number: CN202110785733.0A
Authority: CN
Inventors: 李明; 艾凡; 金丹灵
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-07-12
Filing date: 2021-07-12
Publication date: 2023-01-17
Also published as: WO2023284444A1

Abstract

The application provides a method and a device for optical fiber measurement, comprising the following steps: determining the size of a first SRS energy transfer according to the energy transfer relationship between at least two service lights and corresponding OTDR pulse signals, wherein the at least two service lights comprise a first service light and a second service light, the wavelengths or powers of the first service light and the second service light are different, the first service light and the first OTDR pulse signals are transmitted simultaneously, and the second service light and the second OTDR pulse signals are transmitted simultaneously; and generating a target OTDR test curve according to the first OTDR test curve and the first SRS energy transfer size for optical fiber measurement. And calculating the SRS transferred energy by measuring the OTDR test curve under different service lights and the energy relation of the different service lights, and further recovering the OTDR test curve which is not influenced by the SRS to determine the optical fiber loss condition.

Description

Method and apparatus for optical fiber measurement

Technical Field

The present application relates to the field of optical communications, and more particularly, to a method and apparatus for fiber optic measurements.

Background

Currently, optical fibers are gaining attention as important transmission media in optical communication systems. The optical fiber itself comprises a large number of fusion joints, jumping fibers and single boards, and the positions can affect the signal transmission quality in the use process. Generally, an Optical Time Domain Reflectometer (OTDR) may be used to determine the transmission characteristics of each position of the optical fiber, thereby improving the quality of the optical fiber.

However, the stimulated raman scattering effect is widely existed in the optical fiber transmission system, so that energy transfer easily occurs between optical signals of different frequencies in the optical fiber, and the optical fiber loss result of the OTDR measurement is not accurate.

Therefore, how to enable the OTDR to acquire accurate fiber measurement information is an urgent problem to be solved.

Disclosure of Invention

The application provides a method and a device for optical fiber measurement, which can enable OTDR to acquire accurate optical fiber measurement information.

In a first aspect, a method for optical fiber measurement is provided, which is applied to an optical network system, and the method may be performed by a network manager or a network element.

The method comprises the following steps: determining the energy transfer size of a first Stimulated Raman Scattering (SRS) according to the energy transfer relationship between at least two kinds of service lights and corresponding Optical Time Domain Reflectometer (OTDR) pulse signals, wherein the at least two kinds of service lights comprise a first service light and a second service light, the wavelengths or powers of the first service light and the second service light are different, the first service light and the first OTDR pulse signals are transmitted simultaneously, the second service light and the second OTDR pulse signals are transmitted simultaneously, and the energy transfer size of the first SRS corresponds to the first service light; and generating a target OTDR test curve according to the first OTDR test curve and the first SRS energy transfer size, wherein the first OTDR test curve is generated by coupling the first OTDR pulse signal and the first service light, and the target OTDR test curve is used for optical fiber measurement.

According to the scheme provided by the application, through measuring the OTDR test curve under the condition of different service lights for multiple times and the energy relation injected by each service light during multiple times of measurement, the SRS transfer energy is calculated, and the OTDR signal curve which is not influenced by the SRS is recovered, so that the OTDR can accurately measure the optical fiber loss.

With reference to the first aspect, in certain implementations of the first aspect, the at least two service lights include at least one of the following optical signals: signal light originating from the optical channel transport unit OTU, dummy light for filling the channel.

With reference to the first aspect, in some implementations of the first aspect, the number of wavelength channels in the optical network system is increased or decreased to obtain the first service light and the second service light, where the number of wavelength channels or the wavelength range between the first service light and the second service light is different.

With reference to the first aspect, in some implementation manners of the first aspect, optical power of service light in an optical network system is adjusted to obtain first service light and second service light, where optical power of the first service light and optical power of the second service light are different.

With reference to the first aspect, in certain implementations of the first aspect, the first SRS energy transfer size Δ Ρ _SRS1 Satisfies the following conditions:

second SRS energy transfer size Δ P _SRS2 Satisfies the following conditions:

wherein the second SRS energy transfer size is determined according to the energy relation of at least two service lights, the second SRS energy transfer size corresponds to the second service light, v _i Is the frequency, v, of the ith service light _j Frequency, v, of the jth service light _OTDR1 Is the frequency, v, of the first OTDR pulse signal _OTDR2 Is the power, P, of the second OTDR pulse signal _si Is the power of the ith traffic light, P _sj Is the power of the jth service light, P _OTDR1 Is the power, P, of the first OTDR pulse signal and the second OTDR pulse signal _OTDR2 Is the power of the second OTDR pulse signal, g _R (v _i -v _OTDR1 ) Is the Raman gain coefficient between the first OTDR pulse signal and the ith service light, g _R (v _j -v _OTDR2 ) As a second OTDR pulse signalAnd a Raman gain coefficient between the jth service light and the j-th service light, wherein m and n are the numbers of the first service light and the second service light respectively, m, n, i and j are integers which are larger than zero, i is smaller than or equal to m, j is smaller than or equal to n, K is a proportionality coefficient, and K is a real number.

With reference to the first aspect, in certain implementations of the first aspect, the first OTDR test curve trace ₁ And a second OTDR test curve trace ₂ The difference Δ trace between satisfies:

Δtrace＝trace ₁ -trace ₂ ＝ΔP _SRS1 -ΔP _SRS2 ，

wherein the second OTDR test curve trace ₂ Is generated by coupling the second OTDR pulse signal with the second service light.

With reference to the first aspect, in certain implementations of the first aspect, the amount of energy transfer Δ P between the OTDR pulse signal and the first traffic light _SRS1 Also satisfies:

with reference to the first aspect, in certain implementations of the first aspect, the target OTDR test curve trace ₀ Satisfies the following conditions:

trace ₀ ＝trace ₁ -ΔP _SRS1 。

similarly, the second SRS energy transfer size Δ P _SRS2 Also satisfies:

correspondingly, the target OTDR test curve trace ₀ Also satisfies:

trace ₀ ＝trace ₂ -ΔP _SRS2 。

in a second aspect, there is provided an apparatus for optical fiber measurement, applied to an optical network system, including: the determining unit is configured to determine, according to an energy transfer relationship between at least two kinds of service light and corresponding optical time domain reflectometer OTDR pulse signals, a first stimulated raman scattering SRS energy transfer size, where the at least two kinds of service light include first service light and second service light, the first service light and the second service light are different in wavelength or power, the first service light and the first OTDR pulse signal are transmitted at the same time, the second service light and the second OTDR pulse signal are transmitted at the same time, and the first SRS energy transfer size corresponds to the first service light; and generating a target OTDR test curve according to the first OTDR test curve and the first SRS energy transfer size, wherein the first OTDR test curve is generated by coupling the first OTDR pulse signal and the first service light, and the target OTDR test curve is used for optical fiber measurement.

With reference to the second aspect, in some implementations of the second aspect, the at least two service lights include at least one of the following optical signals: signal light originating from the optical channel transport unit OTU, dummy light for filling the channel.

With reference to the second aspect, in some implementations of the second aspect, the processing unit is configured to increase or decrease the number of wavelength channels in the optical network system to obtain the first service light and the second service light, where the number of wavelength channels or the wavelength range between the first service light and the second service light is different.

With reference to the second aspect, in some implementation manners of the second aspect, the processing unit is further configured to adjust optical power of service light in the optical network system to obtain first service light and second service light, where optical power of the first service light and the optical power of the second service light are different.

In certain implementations of the second aspect in combination with the second aspect, the first SRS energy transfer size Δ Ρ _SRS1 Satisfies the following conditions:

second SRS energy transfer size Δ P _SRS2 Satisfies the following conditions:

wherein the second SRS energy transfer size is determined according to the energy relation of at least two service lights, the second SRS energy transfer size corresponds to the second service light, v _i Is the frequency, v, of the ith service light _j Is the frequency, v, of the jth service light _OTDR1 Is the frequency, v, of the first OTDR pulse signal _OTDR2 Is the power of the second OTDR pulse signal, is the power of the ith traffic light, P _sj Is the power, P, of the jth service light _OTDR1 Is the power, P, of the first OTDR pulse signal _OTDR2 Is the power of the second OTDR pulse signal, g _R (v _i -v _OTDR1 ) Is the Raman gain coefficient between the first OTDR pulse signal and the ith service light, g _R (v _j -v _OTDR2 ) The number of the first OTDR pulse signal and the number of the second OTDR pulse signal are respectively equal to the number of the jth service light, m and n are integers which are larger than zero, i is smaller than or equal to m, j is smaller than or equal to n, K is a proportionality coefficient, and K is a real number.

With reference to the second aspect, in certain implementations of the second aspect, the first OTDR test curve trace ₁ With a second OTDR test curve trace ₂ The difference Δ trace between satisfies:

Δtrace＝trace ₁ -trace ₂ ＝ΔP _SRS1 -ΔP _SRS2

With reference to the second aspect, in certain implementations of the second aspect, the amount of energy transfer Δ P between the OTDR pulse signal and the first traffic light _SRS1 Also satisfies:

with reference to the second aspect, in certain implementations of the second aspect, the target OTDR test curve trace ₀ Satisfies the following conditions:

trace ₀ ＝trace ₁ -ΔP _SRS1 。

similarly, the second SRS energy transfer size Δ P _SRS2 Also satisfies:

correspondingly, the target OTDR test curve trace ₀ Also satisfies:

trace ₀ ＝trace ₂ -ΔP _SRS2 。

in a third aspect, an optical network system is provided, which includes: the system comprises an Optical Time Domain Reflectometer (OTDR), an optical Fiber Interface Unit (FIU) and a Wavelength Selection Switch (WSS);

the wavelength selective switch WSS is used for acquiring at least two service lights, wherein the at least two service lights comprise a first service light and a second service light, and the wavelength or the power of the first service light is different from that of the second service light; the optical time domain reflectometer OTDR comprises a laser, a first Optical Time Domain Reflectometer (OTDR) module and a second Optical Time Domain Reflectometer (OTDR) module, wherein the laser is used for transmitting a first OTDR pulse signal and a second OTDR pulse signal to an optical fiber link to be detected, the first OTDR pulse signal is transmitted with first service light at the same time, and the second OTDR pulse signal is transmitted with second service light at the same time; the optical detector is used for receiving a first optical signal and a second optical signal reflected by an optical fiber link to be detected, wherein the first optical signal corresponds to the first OTDR pulse signal, and the second optical signal corresponds to the second OTDR pulse signal; the processor is used for generating a first OTDR test curve according to the first optical signal received by the optical detector and generating a second OTDR test curve according to the second optical signal received by the optical detector;

an optical fiber interface unit FIU for optically coupling the first OTDR pulse signal with the first service and for optically coupling the second OTDR pulse signal with the second service.

In a fourth aspect, a communication apparatus is provided, including: means or elements for implementing the method of the first aspect or any of its possible implementations.

In a fifth aspect, the present application provides a computer-readable storage medium having stored thereon computer instructions which, when executed on a computer, cause a method as in the first aspect or any one of the possible implementations of the first aspect to be performed.

In a sixth aspect, the present application provides a computer program product comprising computer program code to, when run on a computer, cause a method as in the first aspect or any one of the possible implementations of the first aspect to be performed.

In a seventh aspect, the present application provides a chip, including: a processor, configured to invoke and execute the computer program from the memory, so that the communication device installed with the chip performs the method according to the first aspect or any one of the possible implementation manners of the first aspect.

According to the scheme of the embodiment of the application, an OTDR test curve under two or more different service lights is respectively measured, the size of Stimulated Raman Scattering (SRS) transfer energy of OTDR signal light is calculated according to the multiple OTDR test curves and the energy relation of service light injection in multiple measurements, and the OTDR signal curve which is not affected by SRS is recovered to obtain an accurate OTDR measurement result. The realization method can ensure that the OTDR can accurately measure the information such as optical fiber attenuation and the like, and ensure the transmission quality of signals.

Drawings

Fig. 1 is a schematic diagram of an example of an online transmission system to which the present application is applied.

Fig. 2 is a schematic diagram of an example of an optical time domain reflectometer structure to which the present application is applied.

Fig. 3 is a schematic diagram showing an example of stimulated raman scattering power transfer to which the present application is applied.

Fig. 4 is a schematic diagram showing an example of the relationship between the normalized raman gain coefficient and the frequency difference to which the present application is applied.

Fig. 5 is a schematic diagram of an example of the test results of the optical time domain reflectometer under different service light injections to which the present application is applied.

Fig. 6 is a schematic diagram showing an example of a method for measuring an optical fiber to which the present application is applied.

Fig. 7 is a schematic diagram showing an example of the results of the optical fiber measurement to which the present application is applied.

Fig. 8 is another exemplary illustration of results for fiber optic measurements to which the present application is applicable.

Fig. 9 is a schematic view showing an example of an apparatus for optical fiber measurement to which the present invention is applied.

Fig. 10 is another exemplary view of an apparatus for optical fiber measurement to which the present application is applied.

Detailed Description

The technical solution in the present application will be described below with reference to the accompanying drawings.

Optical fiber communication is a communication mode in which light waves are used as carriers and optical fibers are used as transmission media.

From a physical point of view, the optical fiber can be divided into two parts, namely a proximal optical fiber and a distal optical fiber. The optical fiber is used for connecting optical devices in a site, and the optical fiber is used as a near-end optical fiber. An off-site structure is formed between the ODP and the transmission receiving end, and an optical fiber used for transmitting signals outside the site is used as a far-end optical fiber. Specifically, the station typically includes optical elements such as a multiplexer/demultiplexer unit, a wavelength division multiplexer unit, an optical fiber connector, a flange, and an optical attenuator, which are connected to a transmission transmitting end. The optical fiber connecting these optical devices is the near-end optical fiber, and the optical fiber pulled out of the station is the far-end optical fiber.

The optical fiber comprises a large number of fusion joints, jumping fibers and single plates, transmission loss and damage are easy to occur at the positions in the using process, and meanwhile, most of manufacturing materials of the optical fiber are glass and are fragile. Therefore, in the use process, the connection between the optical device and the proximal optical fiber, the fusion point of the optical fiber, the occurrence of fracture and bending of the optical fiber, and the like all affect the quality of signal transmission, these conditions can be called events, and the types of events can generally include attenuation, gain, reflection and tail end, and the quality of the optical fiber can be repaired and improved only by accurately identifying these events. The location of events in the fiber is determined using an Optical Time Domain Reflectometer (OTDR). In general, an OTDR is connected to a multiplexer/demultiplexer, and transmits a pulse laser beam to an optical fiber and receives an optical signal reflected by the pulse laser beam propagating through the optical fiber. From the intensity change of the received light, the transmission characteristics of each position of the optical fiber can be judged, and further, the existence of an event and the position of the event can be judged.

Fig. 1 is a schematic diagram of an example of an online transmission system to which the present application is applied. As shown in fig. 1, the online transmission system includes an Optical Time Domain Reflectometer (OTDR) 110, a service light, a Wavelength Selective Switch (WSS), a Fiber Interface Unit (FIU) 120, an optical fiber 130, and the like.

In the on-line transmission process, the pulse signal emitted by the OTDR is transmitted simultaneously with the service light, and typically, the wavelength of the OTDR pulse signal is 1490nm to 1510nm, and the service light includes signal light originating from an optical channel transport unit (OTU) and dummy light (e.g., a C-band optical signal and/or an L-band optical signal) for filling a channel. Among them, the service light generally belongs to the capacity ranges of the C band (C band) and the L band (L band). The OTDR includes a transmitter Tx, which may be, for example, an Optical Supervisory Channel (OSC) transmitter. Illustratively, OSC signals modulated using OTDR are sent from the OTDR and fed into the optical fiber under test. The OTDR uses the OSC signal to monitor the fibre loss events in the fibre under test, which events may include fresnel reflections and/or rayleigh backscattering. Among them, the FIU120 is a coupler for coupling different waveforms. For example, the FIU couples the OSC signal and the C-band signal. Illustratively, the fiber 130 may provide a 155Mbps data link for transmitting the OSC signals. The OTDR may be coupled with a computer device (e.g., a server) to provide or receive control information and OTDR information.

Fig. 2 is a schematic diagram of an example of an OTDR structure to which the present application is applied. As shown in fig. 2, the OTDR includes: a laser (laser) 201, an optical detector (APD) 202, a processor 203, a laser driver 204, an optical circulator (circulator), and the like. Wherein the processor 203 comprises: a trans-impedance amplifier (TIA), a Low Noise Amplifier (LNA), an analog filter unit, an analog-to-digital converter (ADC), a logic processing unit, a signal processing unit, and the like. It should be understood that the OTDR may also include a Digital Signal Processor (DSP), a pulse generator, an amplifier (amplifier), and other functional devices.

The laser is used for emitting test light to the optical fiber link to be tested, and the laser in the traditional OTDR can be adopted. The DSP triggers a pulse generator of the laser to generate a pulse signal, and the pulse signal is converted into a control signal of the laser through a laser driver, so that the laser emits light, namely test light is generated to enter an optical fiber link to be tested. And acquiring events such as an optical splitter, a connection point and the like by testing scattered signals and reflected signals generated by light in the optical fiber link to be tested.

The optical circulator is used for receiving the test optical signal transmitted by the laser and outputting the test optical signal to the optical fiber link to be tested.

The photo detector APD is used to convert the received optical signal into a current signal that is proportional to the optical intensity of the optical signal.

The digital processor DSP is used to generate instructions that cause the pulse generator to generate a pulse signal, which may contain information on pulse width, period, etc. Illustratively, the DSP generates periodic trigger pulses that are adjusted by a pulse generator to a signal of fixed pulse width and duty cycle. Then, the laser driver completes high-power driving, so that the laser generates pulse laser of a monitoring wave band.

The pulse generator is connected with the DSP and used for generating corresponding pulse signals when receiving instructions of the DSP. Illustratively, one pulse signal is generated in one test period, or a plurality of repetitive pulse signals of fixed pulse width and duty ratio are generated in one test period.

And the laser driver is connected with the pulse generator and is used for converting the pulse signal generated by the pulse generator into the control signal. The control signal is used to drive the laser to emit OTDR pulse signals of corresponding pulse width and power intensity.

Illustratively, the laser driver 204 is configured to send instructions to the laser 201, and control the laser 201 to emit a pulsed laser signal according to the instructions. The laser 201 is used for emitting pulse laser, the optical detector APD 202 is used for receiving optical signals reflected by an optical fiber to be tested, and the processor 203 is used for processing the optical signals received by the APD 202 into test data.

Specifically, the signal processing unit drives the laser 201 to emit OTDR pulse signals with corresponding pulse width and power intensity through the laser driver 204 according to the parameters configured by the user. The laser 201 emits a pulsed laser signal of a corresponding pulse width and power intensity in accordance with instructions sent by the laser driver. Optionally, an optical circulator is disposed at a port of the optical fiber to be tested to distinguish an incident signal from a reflected signal. An OTDR pulse laser signal emitted by the laser 201 is injected into the optical fiber link to be tested through the optical circulator to be tested, and an OTDR detection signal reflected back through the optical fiber link is received by the optical detector 202 through the optical circulator. The processor 203 converts the received optical signal into a current signal, converts the current signal into a voltage signal with a proper amplitude through the transimpedance amplifier TIA and the low noise amplifier LNA, reduces noise in the voltage signal through the analog filtering unit, and converts the noise-reduced voltage signal into a corresponding digital signal through the analog-to-digital converter ADC acquisition unit. At this time, the logic processing unit may process the digital signal into displayable OTDR test data according to the logic operation, and transmit to the signal processing unit.

It will be appreciated that both the rayleigh backscatter and fresnel reflected light signals from each branch in the on-line transmission system will return through the fiber backbone and eventually enter the optical detector 202 through the optical circulator. The intensity of the rayleigh backscatter and fresnel reflected light signals is related to the pulse width and light intensity of the test optical signal emitted by the OTDR. Generally, the greater the optical power, the greater the returned optical signal.

The optical time domain reflectometer OTDR is an optoelectronic integration instrument manufactured by using backscattering generated by rayleigh scattering of light in an optical fiber and fresnel reflection generated by discontinuous points of light in the optical fiber. The basic principle of OTDR operation is to analyze the transmission characteristics of the fiber, such as length, attenuation, and fault, by detecting the energy distribution curve of the back-scattered light of the pulse laser on the fiber line with time (distance). An optical pulse is input to the optical fiber to be tested, when the optical pulse is transmitted forwards along the optical fiber line, part of signals can be scattered and reflected back, and the signals are continuously sampled at high speed to obtain a curve reflecting the characteristics of attenuation, fault and the like of the optical fiber.

OTDR measures the scattered signal of light. The scattered signal of light is related to the peak power and pulse width of the probe pulse light, and decreases as the transmission distance increases. Usually, the OTDR sets a range to be tested, i.e. a test range, in the test process, where the test range may be equal to or shorter than the length of the optical fiber to be tested. The test range of the OTDR is realized by controlling the test time of each pulse in the pulse laser, and the test time of each pulse is the time required from the emission end of the pulse OTDR to the end point of the test range and then from the end point of the test range to the emission end of the OTDR. The emission time interval between two adjacent pulses in the pulse laser is the test time of each pulse.

Fig. 3 is a schematic diagram of an example of stimulated raman scattering SRS power transfer of a Wavelength Division Multiplexing (WDM) signal to which the present invention is applied. Stimulated raman scattering SRS is a broadband effect related to the interaction between light and silicon atom vibration modes, and widely exists in optical fiber transmission systems, mainly resulting in energy transfer between optical signals of different frequencies in the optical fiber.

It should be understood that wavelength division multiplexing WDM is a technique that combines optical carrier signals (carrying various information) of two or more different wavelengths together at a transmitting end via a multiplexer (also called a multiplexer) and couples them into the same optical fiber on an optical line for transmission.

As shown in fig. 3, the left diagram is a schematic diagram of an input optical signal, it can be considered that the power of a plurality of input signals with different wavelengths is the same when the input optical signals are input, and after the input optical signals are transmitted through an optical fiber link, the right diagram is a schematic diagram of the output of the plurality of input optical signals with different wavelengths. It can be seen that the signal power is reduced for short wavelengths. It is considered that a signal having a short wavelength transfers energy to a signal having a long wavelength. For example, for an online transmission system, when the OTDR optical signal is transmitted simultaneously with the service light, it is usually the OTDR optical signal that transfers energy to the service light.

The amount of energy transfer of the SRS between the two signals of frequencies v1 and v2 can be calculated by the following formula:

ΔP _SRS ∝g _R (Δv)*P _v1 *P _v2

wherein, P _v1 And P _v2 Power of two signals, Δ v is the frequency difference of the two signals, g _R (Δ v) is a raman gain coefficient between the two signal lights. I.e. the middle graph in fig. 3 represents the normalized raman gain coefficient g _R (Δ v) (dB) with the signal light wavelength λ. It can be seen that SRS energy transfer and power P of the two signals _v1 And P _v2 And a Raman gain coefficient g _R (Δ v) is proportional. And, g _R (Δ v) is a positive number when the frequency difference Δ v between the two signals is positive, and a negative number when Δ v is negative.

Fig. 4 is a schematic diagram showing an example of the relationship between the normalized raman gain coefficient and the frequency difference to which the present application is applied. As shown in fig. 4, the abscissa may represent the frequency difference between the OTDR signal and the traffic light (in terahertz, THz) and the ordinate is the normalized raman gain coefficient (in dB). Wherein, due to the stimulated Raman scattering SRS energy transfer, the normalized Raman gain coefficient is maximum near the frequency difference of 13.2THz, and the Raman gain coefficient after the frequency difference exceeds 25THz is very small.

The common OTDR wavelength is in the vicinity of 1625nm, 1510nm and the like, and is in the low-loss window of the optical fiber. Experiments show that for 1520 nm-1625 nm service light, the influence of SRS effect can be effectively avoided by using the OTDR with the wavelength of 1310 nm. However, the loss of the OTDR having a wavelength of 1310nm in the optical fiber is higher than the loss of the optical fiber having a wavelength of 1500nm, which makes the OTDR detection distance limited.

Fig. 5 is a schematic diagram of an example of an OTDR test result of an optical time domain reflectometer under different service light injections in an online scenario, which is applicable to the present application. That is, the OTDR uses the returned optical signal from the optical fiber link under test to generate OTDR trace information, which includes the power trace of the returned optical signal.

The OTDR obtains attenuation information by using back-scattered light generated when light propagates in an optical fiber, and can be used to measure the attenuation of the optical fiber, the splice loss, the location of a fault point of the optical fiber, and to know the loss distribution of the optical fiber along the length. Due to non-uniform density of the fiber material, non-uniform doping composition, and imperfections in the fiber itself, scattering occurs at every point along the length of the fiber as light is transmitted through the fiber. The OTDR records the intensity of the scattered light collected at each time point. Because the speed of light is fixed, the time for collecting signals has a corresponding relation with the transmission distance of light in the optical fiber, so that the time can be converted into the length of the optical fiber.

As shown in fig. 5, the OTDR test curve quantifies the degree information of fresnel reflection and rayleigh scattering. Where the abscissa represents the test distance, i.e., the length of the fiber under test (in km), and the ordinate represents the relative intensity of the returning optical signal (in dB). The measured optical fiber loss coefficient is about 0.19dB/km when no service light exists, and the measured optical fiber loss coefficients are about 0.25dB/km and 0.35dB/km respectively after C band service light and C band + L band service light are injected respectively. It can be seen from this curve that the relative intensity is gradually decreasing with increasing length of the fiber, but the trend is very gradual. Additional losses and reflections occur due to fusion splices, breaks in the fiber, e.g., the OTDR trace exhibits a peak at 80km, which is a simulated reflection event, attenuation event, etc. OTDR measurements rely on these events to analyze the state of the fiber link and to deduce the location of these reflection and attenuation events based on the length of the fiber.

This means that, during the on-line transmission process, the OTDR signal may have energy transfer with the service light due to the SRS effect. Since the traffic light is different, the SRS effect is also different. Therefore, the OTDR cannot measure the real information such as the fiber attenuation, and the OTDR test result is inaccurate.

To sum up, for the online transmission scenario, energy transfer may occur between the OTDR signal and the service light due to the SRS effect, so that the OTDR may not accurately measure information such as optical fiber loss.

In view of this, the technical solution of the present application provides an OTDR test curve under two different service lights, which is measured by an OTDR test method. Through the two curves and the energy relation of the service light injection during two times of measurement, the size of the OTDR signal light SRS transfer energy is calculated, and then the OTDR signal curve which is not influenced by the SRS is restored, and a correct measurement result is obtained.

In order to facilitate understanding of the embodiments of the present application, the following descriptions are made:

in the present application, "at least two" means two or more. "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone, wherein A and B can be singular or plural. In the description of the text of this application, the character "/" generally indicates that the former and latter associated objects are in an "or" relationship. In the formula of the present application, the character "/" indicates that the preceding and following related objects are in a relationship of "division".

It is to be understood that the various numerical references referred to in the embodiments of the present application are merely for descriptive convenience and are not intended to limit the scope of the embodiments of the present application. The sequence numbers of the above processes do not mean the sequence of execution, and the execution sequence of each process should be determined by its function and inherent logic, and should not limit the implementation process of the embodiment of the present application.

In the embodiments of the present application, "first", "second", and various numerical references indicate distinction for convenience of description, and do not limit the scope of the embodiments of the present application. For example, different indication information is distinguished.

In this application, "for indicating" may include for direct indication and for indirect indication. When a certain indication information is described for indicating a, the indication information may be included to directly indicate a or indirectly indicate a, and does not mean that a is necessarily carried in the indication information.

The specific indication method may be any of various existing indication methods, such as, but not limited to, the above indication methods, various combinations thereof, and the like. The specific details of various indication modes can refer to the prior art, and are not described in detail herein. As can be seen from the above description, when a plurality of information of the same type are required to be indicated, for example, different information may be indicated differently. In a specific implementation process, a required indication manner may be selected according to a specific need, and the indication manner selected in the embodiment of the present application is not limited, so that the indication manner related to the embodiment of the present application should be understood to cover various methods that enable a party to be indicated to obtain information to be indicated.

The method provided by the embodiment of the application will be described in detail below with reference to the accompanying drawings.

Fig. 6 is a schematic flowchart of a method for measuring an optical fiber according to an embodiment of the present application, where the specific steps 600 include:

s610, determining the energy transfer size of the first stimulated Raman scattering SRS according to the energy transfer relation between at least two kinds of service light and the corresponding OTDR pulse signals.

In order to facilitate understanding of the technical solution of the present application, the technical solution of the present application is exemplarily described below by taking two measurements as an example.

That is, the at least two service lights include a first service light and a second service light, and the first service light and the second service light have different wavelengths or powers.

The first SRS energy transfer size is used to indicate an energy transfer amount between an OTDR pulse signal of an optical time domain reflectometer and corresponding service light, where the OTDR pulse signal and the corresponding service light signal are transmitted simultaneously.

Illustratively, the first SRS energy transfer size corresponds to the first traffic light, and is used to indicate an energy transfer amount between the first OTDR pulse and the first traffic light when the two are transmitted simultaneously.

In this embodiment of the present application, the energy transfer relationship between at least two service lights and corresponding OTDR pulse signals of the optical time domain reflectometer includes: energy conversion of first service light and corresponding first OTDR pulse signalShift relation Δ P _SRS1 And the energy transfer relationship Δ P between the second service light and the corresponding first OTDR pulse signal _SRS2 The ratio, difference, etc. between. For example, according to the proportional relationship of the following formula (3) and the difference relationship of the following formula (5), the energy value of the first service light and the energy value of the second service light can be determined, and then the OTDR measurement curve that is not affected by the SRS can be recovered, and an accurate optical fiber loss condition can be obtained.

By way of example and not limitation, each of the at least two service lights comprises at least one of the following optical signals: signal light originating from the optical channel transport unit OTU, dummy light for filling the channel.

In general, the energy transfer size Δ P for the first SRS _SRS1 The following formula can be used for the calculation of (c):

similarly, the second SRS energy transfer size Δ P _SRS2 The following formula can be used for the calculation of (c):

the second SRS energy transfer size may also be determined according to an energy transfer relationship between at least two service lights and corresponding OTDR pulse signals, where the second SRS energy transfer size corresponds to the second service light and is used to indicate an energy transfer amount between the second OTDR pulse and the second service light when the two are transmitted simultaneously. v. of _i Is the frequency, v, of the ith service light _i Is the frequency, v, of the jth service light _OTDR1 Is the frequency, v, of the first OTDR pulse signal _OTDR2 Is the frequency, P, of the second OTDR pulse signal _si Is the power of the ith traffic light, P _sj Is the power of the jth service light, P _OTDR1 Is the power, P, of the first OTDR pulse signal _OTDR2 Is the power of the second OTDR pulse signal, g _R (v _i -v _OTDR1 ) Is a first OTDR pulseRaman gain coefficient between signal and ith service light, g _R (v _j -v _OTDR2 ) And the Raman gain coefficient between the second OTDR pulse signal and the jth service light, wherein m and n are the numbers of the first service light and the second service light in two times of measurement respectively, m, n, i and j are integers larger than zero, i is smaller than or equal to m, j is smaller than or equal to n, K is a proportionality coefficient, and K is a real number.

It is understood that in the examples of the present application, K and P _OTDR It can be predicted in advance or no measurement is required. Then at K and P _OTDR When the specific numerical value cannot be determined, the delta P can be further determined by the quotient of the two values _SRS1 And Δ P _SRS2 The energy relationship between them. Namely:

in the above formula (3), the frequencies and powers of the first OTDR pulse signal and the second OTDR pulse signal may be the same or different. The present application is not limited to this, and it is only necessary to determine the proportional relationship between the first SRS energy transfer size and the second SRS energy transfer size in two measurements.

In the embodiment of the present application, the determination of the first service light and the second service light may be implemented in the following manners. Namely:

a possible implementation manner may be to increase or decrease the number of wavelength channels in the optical network system, that is, the channels of the service lights may be closed or opened by devices such as the WSS under different service light conditions, so as to obtain the first service light and the second service light.

The number of wavelength channels or wavelength ranges between the first service light and the second service light are different.

Illustratively, at the first measurement, both the signal light in the traffic light and the dummy optical channel for channel filling are opened. At the time of the second measurement, the signal light in the service light and the dummy light channel for channel filling are closed by half at equal intervals.

Specifically, when the measurement is performed for the first time, the number of channels of the traffic light is set to X. And setting the number of channels of the service light as Y during the second measurement. Therefore, the number of wavelength channels of the service light is different in the two measurements, and the corresponding wavelength ranges are also different. Taking the service light of the C spreading channel as an example, it is assumed that there are 120 optical signal transmission channels, and the number of signal channels occupied by the OTDR signal light in transmission is 10. Then, in the first measurement, the signal light and the dummy light in the service light occupy all the remaining 110 channels when transmitted. In the second measurement, the signal light and the dummy light in the service light only occupy half of the remaining 110 channels when transmitted.

It should be noted that, in a specific implementation, a channel occupied by the signal light is usually unchanged, and for the second measurement, a signal channel that is closed by half at an equal interval may be regarded as a dummy light channel that is closed by half at an equal interval.

In another possible implementation manner, the first service light and the second service light may be obtained by adjusting optical power of the service light in the optical network system, that is, optical power between the first service light and the second service light is different.

Illustratively, the power of the first traffic light is set to X dB at the time of the first measurement. At the time of the second measurement, the power of the second traffic light is set to Y dB. Therefore, the power of the service light measured twice is different, and the corresponding service light is selected differently.

Exemplarily, before calculating the first SRS energy transfer size, a first OTDR test curve corresponding to the first service light and a second OTDR test curve corresponding to the second service light need to be measured respectively.

Specifically, for the online transmission system shown in fig. 1, at the time of the first measurement, both the signal light in the service light and the dummy optical channel for channel filling are opened, i.e., the first service light. The first OTDR pulse signal and the first service light are transmitted simultaneously, an optical signal is generated through FIU coupling and then transmitted to the optical fiber link to be tested, a first OTDR test curve is generated according to the reflected optical signal and is recorded as trace ₁ . At the time of the second measurement, willThe signal light in the service light and the dummy light channel used for channel filling are equally spaced and closed half, i.e. the second service light. The second OTDR pulse signal and the second service light are transmitted simultaneously, an optical signal is generated through FIU coupling and then transmitted to the optical fiber link to be tested, a second OTDR test curve is generated according to the reflected optical signal and is recorded as trace ₂ . At this time, the traffic optical power of the input fiber 130 is reduced by 3dB.

It should be noted that the first OTDR pulse signal and the second OTDR pulse signal may be the same or different.

In an implementation manner, when the first OTDR pulse signal and the second OTDR pulse signal are the same, that is, the wavelength and the power of the first OTDR pulse signal and the second OTDR pulse signal are the same, at this time, only the energy relationship between the first service light and the second service light needs to be determined, and then the first SRS energy transfer size is calculated.

In another implementation manner, when the first OTDR pulse signal and the second OTDR pulse signal are different, that is, the wavelength or the power of the first OTDR pulse signal and the second OTDR pulse signal are different, not only the energy relationship between the first service light and the second service light needs to be determined, but also the energy relationship between the first OTDR pulse signal and the second OTDR pulse signal needs to be determined, so as to calculate the energy transfer size of the first SRS.

The specific determination manner for the energy relationship between the first OTDR pulse signal and the second OTDR pulse signal may refer to the determination manner for the energy relationship between the first service light and the second service light. For brevity, no further description is provided herein.

It should be understood that both implementations described above can solve the technical problem, and the present application is not limited thereto in particular.

Then, the difference between the magnitudes of the energy transfer between the two OTDR measurements satisfies:

Δtrace＝trace ₁ -trace ₂ (4)

it should be noted that, closing the service optical channels at equal intervals is only an exemplary illustration, so as to more clearly describe the technical solutions of the embodiments of the present application, and does not constitute a limitation on the technical solutions provided by the present application.

Optionally, the signal channel of the traffic light is closed by half at unequal intervals, or the signal channel of the traffic light is closed by one third at equal intervals, and so on, in the measurement, this application is not limited to this specifically. The acquisition conditions of different service lights are only used for calculating the power transfer of the SRS through multiple measurements, and further obtaining the OTDR measurement result which is not influenced by the SRS.

The energy transfer between the two OTDR measurement results is also equivalent to the energy transfer between the two service lights, that is, the formula (4) may also satisfy:

Δtrace＝trace ₁ -trace ₂ ＝ΔP _SRS1 -ΔP _SRS2 (5)

then, according to the above equation (3) and equation (5), the energy size of the first SRS transition can be further calculated. Namely:

similarly, the energy size of the second SRS transition satisfies:

illustratively, for the technical solution in the embodiment of the present application, the optical power of the traffic light in the second measurement is half of the optical power of the first measurement, that is, Δ P _SRS1 ＝2ΔP _SRS2 (8) Substituting the formula (8) into the above calculation formula (6) and formula (7), the calculated first SRS transfer amount satisfies:

ΔP _SRS1 ＝2*(trace ₁ -trace ₂ ) (9)

correspondingly, the energy size of the second SRS transfer satisfies:

ΔP _SRS2 ＝Δtrace＝trace ₁ -trace ₂ (10)

s620, generating a target OTDR test curve according to the first OTDR test curve and the first SRS energy transfer size.

Wherein the target OTDR test curve is used for fiber measurement. The specific implementation process of the first OTDR test curve has already been described in detail in step S610, and is not described herein again for brevity.

Thus, according to the first OTDR test curve trace ₁ And formula (6) can recover OTDR signal curve trace not affected by SRS ₀ Comprises the following steps:

trace ₀ ＝trace ₁ -ΔP _SRS1 (11)

likewise, trace according to a second OTDR test curve ₂ With the second SRS energy transfer size (i.e., equation (7)), a target OTDR test curve trace may also be generated ₀ . Namely:

trace ₀ ＝trace ₂ -ΔP _SRS2 (12)

it should be noted that the recovered OTDR signal curves in the above equation (11) and equation (12) are identical. It should be understood that, in the above embodiment, taking two different service light conditions as an example, optical fiber measurement is performed, SRS energy transfer size is calculated, and an OTDR measurement curve that is not affected by SRS is recovered. The implementation manner is only illustrative and does not constitute a limitation to the technical solution of the present application.

Optionally, the OTDR measurement may also be performed on three different service light conditions as an example, and the number of the service lights and the measurement times are not specifically limited in the present application.

Illustratively, according to the method 600, at this time, an OTDR test curve needs to be measured three times, and the three measurement results are compared with each other to determine a proportional relationship and a difference relationship of the three service light energies, so as to recover the trace ₀ Finally, the recovered 3 trace ₀ And averaging to obtain an OTDR measurement result and the like which are not affected by the SRS.

Fig. 7 is a schematic diagram showing an example of the results of the optical fiber measurement to which the present application is applied. As shown in fig. 7, the abscissa represents the fiber length (in km) and the ordinate represents the relative intensity (in dB) of the return optical signal.

It can be seen from this graph that the relative intensity is gradually decreasing as the length of the fiber increases. Additional losses and reflections are generated due to fusion splices, breaks in the fiber, for example, the OTDR trace exhibits a peak at 95km, which is a simulated reflection event, attenuation event, etc. OTDR measurements rely on these events to analyze the state of the fiber link and to deduce the location of these reflection and attenuation events based on the length of the fiber.

Wherein, taking the C-band of the full-wave extended service light as an example, the frequency of the service light is 196.65 to 190.7THz. The dotted line shown in fig. 7 shows that, in an off-line scenario, an OTDR curve that is not affected by SRS and is measured after all service lights are turned off, that is, an OTDR curve without SRS effect, meets trace ₀ ＝trace ₁ -ΔP _SRS1 . The solid line represents an OTDR test curve obtained by measurement after all the service lights (i.e. including 120 service lights at an interval of 50 GHz), i.e. trace1, and the SRS transfer energy included therein is Δ P _SRS1 . At this time, the fiber input power of each service light can be measured by a spectrometer or the like. For example, in the first measurement, the power of the ith traffic light is denoted as P _si . In the second measurement, the power of the jth service light is recorded as P _sj . The dotted line represents an OTDR test curve obtained by measurement after closing half of the service optical channel at equal intervals (correspondingly, the service optical power is reduced by 3 dB), that is, trace2, and the SRS transfer energy included therein is Δ P _SRS2 The wavelength and optical power of the residual channel can be obtained by an instrument device such as a spectrometer. The delta P can be obtained according to the formulas (3) and (5) _SRS1 And Δ P _SRS2 And finally, obtaining the recovered OTDR curve according to the formulas (11) and (12).

In the embodiment of the present application, the traffic channels of half of the closed channels at equal intervals are used, which is equivalent to equations (9) and (10) simplified from equations (6) and (7).

FIG. 8 is another exemplary illustration of results for fiber optic measurements suitable for use with the present application. As shown in fig. 8, the abscissa represents the fiber length (in km) and the ordinate represents the relative intensity (in dB) of the return optical signal.

It can be seen from this plot that the relative intensity is gradually decreasing as the length of the fiber increases. Additional losses and reflections occur due to fusion splices, breaks in the fiber, e.g., OTDR traces exhibit peaks at 95km, which are simulated reflection events, attenuation events, etc. OTDR measurements rely on these events to analyze the state of the fiber link and deduce the location of these reflection and attenuation events based on the length of the fiber.

The dotted line shows an OTDR test curve which is recovered and obtained without stimulated Raman scattering SRS effect according to the technical scheme provided by the application and aiming at the online transmission system. The solid line represents an OTDR curve that is not affected by SRS and is measured after all service lights are turned off in an offline scenario, that is, an OTDR curve without SRS effect.

Therefore, the two curves are almost completely overlapped, which shows that the OTDR measurement result obtained based on the technical scheme of the application is real and accurate, and the processing effect is good.

It should be understood that the graphs shown in fig. 7 and fig. 8 are only exemplary, are used for more clearly explaining the technical solutions of the embodiments of the present application, and do not constitute limitations on the technical solutions provided by the embodiments of the present application. For example, the OTDR measurement may be performed by taking the service light L band as an example, or may also be performed by taking the service light C band + L band as an example.

In summary, the present application provides an on-line scene OTDR measurement SRS compensation scheme, which measures OTDR test curves under two or more different service lights, respectively, calculates the amount of SRS transfer energy of the OTDR signal light according to the energy relationship between the multiple measurement curves and the service light injected during multiple measurements, recovers the OTDR signal curve that is not affected by the SRS, and obtains the OTDR measurement result that is not affected by the SRS. The implementation mode does not need hardware change, can be used in both an online scene and an offline scene, supports the OTDR wavelength to be set in a wave band of 1500-1650 nm and is positioned in an optical fiber low-loss window, and enables the OTDR ranging capability to be stronger.

The method-side embodiment of the present application for optical fiber measurement is described in detail above with reference to fig. 1 to 8, and the apparatus-side embodiment of the present application for optical fiber measurement is described in detail below with reference to fig. 9 and 10. It is to be understood that the description of the apparatus embodiments corresponds to the description of the method embodiments and therefore reference may be made to the method embodiments in the foregoing, for parts which are not described in detail.

Fig. 9 is a schematic block diagram of a communication device provided in an embodiment of the present application. As shown in fig. 9, the communication apparatus 1000 may include a processing unit 1100, a determining unit 1200, and a generating unit 1300.

It is to be understood that the communication device 1000 may include means for performing the method of the method 600 in fig. 6. Also, the units and other operations and/or functions described above in the communication device 1000 are respectively for implementing the corresponding flows of the method 600 in fig. 6.

Exemplarily, the determining unit 1200 is configured to determine a first stimulated raman scattering SRS energy transfer size according to an energy transfer relationship between at least two service lights and corresponding optical time domain reflectometer OTDR pulse signals, where the at least two service lights include a first service light and a second service light, the first service light and the second service light have different wavelengths or powers, the first service light and the first OTDR pulse signal are transmitted simultaneously, the second service light and the second OTDR pulse signal are transmitted simultaneously, and the first SRS energy transfer size corresponds to the first service light.

A generating unit 1300, configured to generate a target OTDR test curve according to the first OTDR test curve and the first SRS energy transfer size, where the first OTDR test curve is generated by optically coupling the first OTDR pulse signal and the first service, and the target OTDR test curve is used for optical fiber measurement.

Optionally, the processing unit 1100 is configured to increase or decrease the number of wavelength channels in the optical network system to obtain the first service light and the second service light, where the number of wavelength channels or the wavelength range between the first service light and the second service light is different.

The processing unit 1100 is further configured to adjust optical power of service light in an optical network system to obtain first service light and second service light, where optical power of the first service light and the second service light is different.

It is also to be understood that the processing unit 1100 in the communication device 1000 may be implemented by at least one processor.

It is further understood that the processing unit 1100 in the communication device 1000 may be implemented by a processor, a microprocessor, an integrated circuit or the like integrated on the chip or system of chips.

Fig. 10 is another schematic block diagram of a communication device 2000 provided in an embodiment of the present application. As shown in fig. 10, the communications device 2000 includes a processor 2010, a transceiver 2020, and a memory 2030. Wherein the processor 2010, the transceiver 2020, and the memory 2030 are in communication with each other via the internal connection path, the memory 2030 is configured to store instructions, and the processor 2010 is configured to execute the instructions stored in the memory 2030 to control the transceiver 2020 to transmit and/or receive signals.

Illustratively, the processor 2010 is configured to determine a first stimulated raman scattering SRS energy transfer size according to an energy transfer relationship between at least two service lights and corresponding optical time domain reflectometer OTDR pulse signals, where the at least two service lights include a first service light and a second service light, the first service light and the second service light have different wavelengths or powers, the first service light and the first OTDR pulse signal are transmitted simultaneously, the second service light and the second OTDR pulse signal are transmitted simultaneously, and the first SRS energy transfer size corresponds to the first service light.

The processor 2010 is further configured to generate a target OTDR test curve according to the first OTDR test curve and the first SRS energy transfer size, where the first OTDR test curve is generated by coupling the first OTDR pulse signal and the first service, and the target OTDR test curve is used for optical fiber measurement.

Optionally, the processor 2010 is further configured to increase or decrease the number of wavelength channels in the optical network system to obtain the first service light and the second service light, where the number of wavelength channels or the wavelength range between the first service light and the second service light is different.

The processor 2010 is further configured to adjust optical power of the service light in the optical network system to obtain a first service light and a second service light, where optical power of the first service light and optical power of the second service light are different.

It is to be understood that the communication device 2000 may be adapted to perform the various steps and/or procedures of the above-described method embodiments. Alternatively, the memory 2030 may include a read-only memory and a random access memory, and provide instructions and data to the processor. The portion of memory may also include non-volatile random access memory. The memory 2030 may be a separate device or may be integrated into the processor 2010. The processor 2010 may be configured to execute the instructions stored in the memory 2030, and when the processor 2010 executes the instructions stored in the memory, the processor 2010 is configured to perform the various steps and/or flows of the above-described method embodiments corresponding to OTDR.

The transceiver 2020 may include a transmitter and a receiver, among others. The transceiver 2020 may further include one or more antennas. The processor 2010 and the memory 2030 and the transceiver 2020 may be devices integrated on different chips. For example, the processor 2010 and the memory 2030 may be integrated within a baseband chip and the transceiver 2020 may be integrated within a radio frequency chip. The processor 2010 and the memory 2030 may also be integrated devices on a single chip with the transceiver 2020. This is not a limitation of the present application.

The transceiver 2020 may also be a communication interface, such as an input/output interface, a circuit, or the like. The transceiver 2020 may be integrated with the processor 2010 and the memory 2020 on the same chip, such as a baseband chip.

It should be understood that the specific examples in the embodiments of the present application are only for helping those skilled in the art to better understand the technical solutions of the present application, and the above specific implementation can be considered as the best implementation of the present application, and not for limiting the scope of the embodiments of the present application.

It should be noted that the actions or methods performed by the controller may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, the actions or methods performed by the controller may be implemented in whole or in part in a computer program product. The computer program product comprises one or more computer instructions or computer programs. The procedures or functions described in accordance with the embodiments of the present application are produced in whole or in part when the computer instructions or the computer program are loaded or executed on a computer. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by wire (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that contains one or more collections of available media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium, which may be a solid state hard disk.

Optionally, the memory and the processor in the foregoing apparatus embodiments may be physically separate units, or the memory and the processor may also be integrated together, which is not limited in this application.

The processor in the embodiments of the present application may be an integrated circuit chip having the capability of processing signals. In implementation, the steps of the above method embodiments may be performed by integrated logic circuits of hardware in a processor or instructions in the form of software. The processor may be a general purpose processor, a Digital Signal Processor (DSP), an application-specific integrated circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, or discrete hardware components. 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 the embodiments of the present application may be directly implemented by a hardware encoding processor, or implemented by a combination of hardware and software modules in the encoding processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in a memory, and a processor reads information in the memory and completes the steps of the method in combination with hardware of the processor.

The memory in the embodiments of the present application may be either volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. The non-volatile memory may be a read-only memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an electrically Erasable EPROM (EEPROM), or a flash memory. Volatile memory can be Random Access Memory (RAM), which acts as external cache memory. By way of example, but not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), dynamic Random Access Memory (DRAM), synchronous Dynamic Random Access Memory (SDRAM), double data rate SDRAM, enhanced SDRAM, SLDRAM, synchronous Link DRAM (SLDRAM), and Direct Rambus RAM (DRRAM). It should be noted that the memory of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It can be clearly understood by those skilled in the art that, for convenience and simplicity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the methods described in the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a U disk, a removable hard disk, a Read Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method for optical fiber measurement, applied to an optical network system, the method comprising:

determining the energy transfer size of a first Stimulated Raman Scattering (SRS) according to the energy transfer relationship between at least two kinds of service lights and corresponding Optical Time Domain Reflectometer (OTDR) pulse signals, wherein the at least two kinds of service lights comprise a first service light and a second service light, the wavelengths or powers of the first service light and the second service light are different, the first service light and the first OTDR pulse signals are transmitted simultaneously, the second service light and the second OTDR pulse signals are transmitted simultaneously, and the energy transfer size of the first SRS corresponds to the first service light;

and generating a target OTDR test curve according to the first OTDR test curve and the first SRS energy transfer size, wherein the first OTDR test curve is generated by coupling the first OTDR pulse signal and the first service light, and the target OTDR test curve is used for the optical fiber measurement.

2. The method of claim 1, wherein the at least two traffic lights comprise at least one of the following optical signals: signal light originating from the optical channel transport unit OTU, dummy light for filling the channel.

3. The method according to claim 1 or 2, characterized in that the method further comprises:

increasing or decreasing the number of wavelength channels in the optical network system to obtain the first service light and the second service light, where the number of wavelength channels or the wavelength range of the first service light is different from that of the second service light.

4. The method according to any one of claims 1 to 3, further comprising:

and adjusting the optical power of the service light in the optical network system to obtain the first service light and the second service light, wherein the optical power of the first service light is different from that of the second service light.

5. Method according to any of claims 1 to 4, characterized in that the first SRS energy transfer size Δ P _SRS1 Satisfies the following conditions:

second SRS energy transfer size Δ P _SRS2 Satisfies the following conditions:

wherein the second SRS energy transfer size is determined according to the energy relation of the at least two service lights, the second SRS energy transfer size corresponds to the second service light, v _i For the frequency, v, of the ith service light _j Is the frequency, v, of the jth service light _OTDR1 Is the frequency, v, of the first OTDR pulse signal _OTDR2 Is the frequency, P, of the second OTDR pulse signal _si Is the power, P, of the ith traffic light _sj Is the power, P, of the jth service light _OTDR Is the power, P, of the first OTDR pulse signal _OTDR2 Is the power, g, of the second OTDR pulse signal _R (v _i -v _OTDR1 ) (ii) a Raman gain coefficient between the first OTDR pulse signal and the ith traffic light, g _R (v _j -v _OTDR2 ) And a raman gain coefficient between the second OTDR pulse signal and the jth service light, where m and n are numbers of the first service light and the second service light, respectively, m, n, i, and j are integers greater than zero, and i is less than or equal to m, j is less than or equal to n, K is a proportionality coefficient, and K is a real number.

6. Method according to claim 5, characterized in that said first OTDR test curve trace ₁ With a second OTDR test curve trace ₂ Δ trace satisfies:

Δtrace＝trace ₁ -trace ₂ ＝ΔP _SRS1 -ΔP _SRS2 ，

wherein the second OTDR test curve trace ₂ Is generated by optically coupling the second OTDR pulse signal with the second service.

7. The method of claim 6, wherein the first SRS energy transfer size Δ P _SRS1 Also satisfies:

8. the method of claim 7, wherein the target OTDR test curve trace ₀ Satisfies the following conditions:

trace ₀ ＝trace ₁ -ΔP _SRS1 。

9. an apparatus for optical fiber measurement, applied to an optical network system, comprising:

a determining unit, configured to determine, according to an energy transfer relationship between at least two service lights and corresponding optical time domain reflectometer OTDR pulse signals, a size of a first stimulated raman scattering SRS energy transfer, where the at least two service lights include a first service light and a second service light, where wavelengths or powers of the first service light and the second service light are different, the first service light and the first OTDR pulse signal are transmitted at the same time, the second service light and the second OTDR pulse signal are transmitted at the same time, and the size of the first SRS energy transfer corresponds to the first service light;

a generating unit, configured to generate a target OTDR test curve according to a first OTDR test curve and the first SRS energy transfer size, where the first OTDR test curve is generated by coupling the first OTDR pulse signal and the first service, and the target OTDR test curve is used for the optical fiber measurement.

10. The apparatus of claim 9, wherein the at least two traffic lights comprise at least one of the following optical signals: signal light originating from the optical channel transport unit OTU, dummy light for filling the channel.

11. The apparatus of claim 9 or 10, further comprising:

a processing unit, configured to increase or decrease the number of wavelength channels in the optical network system to obtain the first service light and the second service light, where the number of wavelength channels or the wavelength range of the first service light is different from that of the second service light.

12. The apparatus according to any one of claims 9 to 11,

the processing unit is further configured to adjust optical power of the service light in the optical network system to obtain the first service light and the second service light, where optical power of the first service light is different from optical power of the second service light.

13. The apparatus according to any of claims 9-12, wherein the first SRS energy transfer size Δ Ρ _SRS1 Satisfies the following conditions:

second SRS energy transfer size Δ P _SRS2 Satisfies the following conditions:

wherein the second SRS energy transfer size is determined according to an energy relation of the at least two service lights, the second SRS energy transfer size corresponds to the second service light, v _i Is the frequency, v, of the ith service light _j Frequency, v, of the jth service light _OTDR1 Is the frequency, v, of the first OTDR pulse signal _OTDR2 Is the frequency, P, of the second OTDR pulse signal _si Is the power, P, of the ith traffic light _sj Is the power, P, of the jth service light _OTDR1 Is the power, P, of the first OTDR pulse signal _OTDR2 Is the power of the second OTDR pulse signal, g _R (v _i -v _OTDR1 ) Is a Raman gain coefficient, g, between the first OTDR pulse signal and the i-th service light _R (v _j -v _OTDR2 ) And a raman gain coefficient between the second OTDR pulse signal and the jth service light, where m and n are numbers of the first service light and the second service light, respectively, and m, n, i, and j are integers greater than zero, where i is less than or equal to m, j is less than or equal to n, K is a proportionality coefficient, and K is a real number.

14. The apparatus of claim 13, wherein the first OTDR test curve trace ₁ With a second OTDR test curve trace ₂ The difference Δ trace of (a) satisfies:

Δtrace＝trace ₁ -trace ₂ ＝ΔP _SRS1 -ΔP _SRS2

15. According to the rightThe apparatus of claim 14, wherein the first amount of SRS energy transfer, Δ Ρ _SRS1 Also satisfies:

16. the apparatus of claim 15, wherein the target OTDR test curve trace ₀ Satisfies the following conditions:

trace ₀ ＝trace ₁ -ΔP _SRS1 。

17. an optical network system, comprising: the system comprises an Optical Time Domain Reflectometer (OTDR), an optical Fiber Interface Unit (FIU) and a Wavelength Selection Switch (WSS);

the wavelength selective switch WSS is configured to obtain at least two service lights, where the at least two service lights include a first service light and a second service light, and the first service light and the second service light have different wavelengths or powers;

the optical time domain reflectometer OTDR comprises a laser, and is used for transmitting a first OTDR pulse signal and a second OTDR pulse signal to a fiber link to be tested, wherein the first OTDR pulse signal is transmitted with the first service light at the same time, and the second OTDR pulse signal is transmitted with the second service light at the same time; an optical detector, configured to receive a first optical signal and a second optical signal reflected by the optical fiber link to be tested, where the first optical signal corresponds to the first OTDR pulse signal, and the second optical signal corresponds to the second OTDR pulse signal; a processor configured to generate a first OTDR test curve according to the first optical signal received by the optical detector, and generate a second OTDR test curve according to the second optical signal received by the optical detector;

the fiber interface unit FIU is configured to optically couple the first OTDR pulse signal and the first service, and to optically couple the second OTDR pulse signal and the second service.

18. A computer storage medium having stored therein computer instructions which, when executed on a computer, cause the computer to perform the method of any one of claims 1 to 8.

19. A chip, comprising: a processor for calling and running a computer program from a memory so that a communication device on which the chip is installed performs the method of any one of claims 1 to 8.

20. A computer program product, characterized in that the computer program code or instructions, when executed on a computer, cause the computer to perform the method according to any of claims 1 to 8.