CN105874727B

CN105874727B - A kind of method and device for detecting optical signal to noise ratio

Info

Publication number: CN105874727B
Application number: CN201480070041.6A
Authority: CN
Inventors: 李朝晖; 马会肖; 王大伟
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2014-03-13
Filing date: 2014-03-13
Publication date: 2018-06-05
Anticipated expiration: 2034-03-13
Also published as: WO2015135173A1; CN105874727A

Abstract

An embodiment of the present invention provides a kind of method and devices for detecting optical signal to noise ratio, are related to the communications field, for reducing the error of the optical signal to noise ratio of light signal to be checked.Described device includes：Signal acquiring unit, coherent reception unit, reference spectra acquiring unit and spectroscopy unit；Signal acquiring unit, for obtaining light signal to be checked；Coherent reception unit for detecting light signal to be checked on the first monitoring point, and obtains the luminous power spectrum of light signal to be checked；Reference spectra acquiring unit for obtaining the link model of optical signal transmission to be detected on the first monitoring point, and determines according to link model the response characteristic of the transmission link of light signal to be checked；It is additionally operable to obtain the first spectrum；And reference spectra is determined according to response characteristic and the first spectrum；Spectroscopy unit, for determining optical signal to noise ratio of the light signal to be checked on the first monitoring point according to the luminous power of light signal to be checked spectrum and reference spectra.The present invention is suitable for the scene of detection optical signal to noise ratio.

Description

Method and device for detecting optical signal-to-noise ratio

Technical Field

The present invention relates to the field of communications, and in particular, to a method and an apparatus for detecting an optical signal-to-noise ratio.

Background

In an optical fiber communication system, in order to manage and monitor an optical network, important parameters in the optical network need to be monitored, and among many parameters, an optical signal to noise ratio can accurately reflect the quality of an optical network operation state, so that the optical signal to noise ratio becomes an important index for measuring the quality of an optical fiber link.

In the prior art, a spectrum analyzer is usually used to obtain a power spectrum of an optical signal to be detected in a certain channel, and a signal spectrum emitted by a transmitter and not passing through any device is used as a reference spectrum, so as to calculate a ratio of optical signal power to optical noise power in the power spectrum of the optical signal to be detected according to the obtained power spectrum and the reference spectrum of the optical signal to be detected, and further calculate an optical signal-to-noise ratio of the optical signal to be detected.

In the process of calculating the osnr, the osnr of the optical signal to be detected is calculated by using a signal spectrum emitted by the transmitter without passing through any device as a reference spectrum, and the signal spectrum emitted by the transmitter needs to pass through some devices having a filtering function in an actual transmission process, so that the signal spectrum emitted by the transmitter is changed in the transmission process, and thus the osnr calculated by using the signal spectrum without passing through any device as the reference spectrum is different from the osnr calculated in the actual transmission process, that is, an error of the osnr of the optical signal to be detected calculated by using the signal spectrum without passing through any device as the reference spectrum is increased.

Disclosure of Invention

The embodiment of the invention provides a method and a device for detecting an optical signal-to-noise ratio, which are used for reducing the error of the optical signal-to-noise ratio of an optical signal to be detected.

In order to achieve the above purpose, the embodiment of the invention adopts the following technical scheme:

in a first aspect, an embodiment of the present invention provides an apparatus for detecting an optical signal-to-noise ratio, including: the device comprises a signal acquisition unit, a coherent receiving unit, a reference spectrum acquisition unit and a spectrum analysis unit; the signal acquisition unit is used for acquiring an optical signal to be detected; the coherent receiving unit is used for detecting the optical signal to be detected on a first monitoring point and acquiring an optical power spectrum of the optical signal to be detected; the reference spectrum acquisition unit is used for acquiring a link model of the optical signal transmission to be detected at the first monitoring point and determining the response characteristic of the transmission link of the optical signal to be detected according to the link model; the reference spectrum acquisition unit is also used for acquiring a first spectrum; wherein the first spectrum is a signal spectrum emitted by an emitting end and not passing through any device; the reference spectrum acquisition unit is further configured to determine a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected and the first spectrum; and the spectrum analysis unit is used for determining the optical signal to noise ratio of the optical signal to be detected on the first monitoring point according to the optical power spectrum of the optical signal to be detected and the reference spectrum.

In a first possible implementation manner of the first aspect, the reference spectrum obtaining unit is further configured to obtain the first spectrum, and includes: the reference spectrum acquisition unit is specifically configured to acquire a modulation format of the optical signal to be detected, and determine the first spectrum according to the modulation format; or, the reference spectrum obtaining unit is specifically configured to determine whether the optical signal to be detected carries a pilot signal, and determine the first spectrum according to the pilot signal when it is determined that the optical signal to be detected carries the pilot signal.

With reference to the first aspect or the first possible implementation manner of the first aspect, in a second possible implementation manner of the first aspect, the apparatus further includes: a storage unit; the storage unit is configured to pre-store a link model for optical signal transmission to be detected, or pre-store a model of at least one network node through which the optical signal to be detected passes during transmission; the reference spectrum obtaining unit, configured to obtain, at the first monitoring point, the link model of the optical signal transmission to be detected, includes: the reference spectrum acquisition unit is specifically configured to acquire, from the storage unit, a link model of optical signal transmission to be detected at the first monitoring point; or, the reference spectrum obtaining unit is specifically configured to determine, at the first monitoring point, a link model for transmission of the optical signal to be detected according to a network node through which the optical signal to be detected passes and a model of the at least one network node stored in the storage unit, where the network node passes and is obtained by a network side.

With reference to the first aspect, or the first or second possible implementation manner of the first aspect, in a third possible implementation manner of the first aspect, the coherent receiving unit includes: the system comprises a polarization control module, a local oscillator laser module, a first polarization beam splitting module, a second polarization beam splitting module, a first optical frequency mixing module, a second optical frequency mixing module, a photoelectric detection module, an analog-to-digital conversion module and a digital signal processing module; the coherent receiving unit, configured to obtain an optical power spectrum of the optical signal to be detected, includes: the local oscillator laser module is used for transmitting local oscillator optical signals at a first frequency interval; the first polarization beam splitting module is configured to split the optical signal to be detected into a first optical signal and a second optical signal that are orthogonal to each other, and input the first optical signal and the second optical signal to the first optical mixing module and the second optical mixing module, respectively; the second polarization beam splitting module is configured to split the local oscillator optical signal into a first local oscillator optical signal and a second local oscillator optical signal that are orthogonal to each other, and input the first local oscillator optical signal and the second local oscillator optical signal to the first optical frequency mixing module and the second optical frequency mixing module, respectively; the polarization control module is configured to control the first optical signal and the first local oscillator optical signal so that directions of the first optical signal and the first local oscillator optical signal are the same, and control the second optical signal and the second local oscillator optical signal so that directions of the second optical signal and the second local oscillator optical signal are the same; the first optical frequency mixing module is configured to perform frequency mixing on the first optical signal and the first local oscillator optical signal to obtain a first frequency mixing signal, and input the first frequency mixing signal to the photodetection module; wherein the first mixing signal comprises at least two mutually orthogonal optical signals; the second optical frequency mixing module is configured to perform frequency mixing on the second optical signal and the second local oscillator optical signal to obtain a second frequency mixing signal, and input the second frequency mixing signal to the photoelectric detection module; wherein the second mixing signal comprises at least two mutually orthogonal optical signals; the photoelectric detection module is configured to detect the first mixing signal and the second mixing signal, obtain an analog optical power signal of the first mixing signal and the second mixing signal, and input the analog optical power signal to the analog-to-digital conversion module; the analog-to-digital conversion module is used for converting the analog optical power signal into a digital optical power signal and inputting the digital optical power signal to the digital signal processing module; the digital signal processing module is used for performing first processing on the digital optical power signal to obtain an optical power spectrum of the optical signal to be detected; the first processing comprises Fast Fourier Transform (FFT), frequency spectrum splicing, power correction and coefficient compensation.

With reference to the first aspect or any one of the first to third possible implementation manners of the first aspect, in a fourth possible implementation manner of the first aspect, the acquiring the optical signal to be detected by the signal acquiring unit includes: the signal acquisition unit is specifically used for acquiring the optical signal to be detected in unidirectional transmission; or, the signal obtaining unit is specifically configured to obtain the optical signal to be detected transmitted in an uplink and the optical signal to be detected transmitted in a downlink.

With reference to the fourth possible implementation manner of the first aspect, in a fifth possible implementation manner of the first aspect, the reference spectrum acquiring unit includes: an uplink reference spectrum acquisition module and a downlink reference spectrum acquisition module; the uplink reference spectrum acquisition module is configured to acquire a link model of an uplink for transmitting the optical signal to be detected at the first monitoring point, and determine a response characteristic of a transmission link of the optical signal to be detected of the uplink according to the link model; the uplink reference spectrum acquisition module is further used for acquiring a first spectrum; the first spectrum is a signal spectrum which is emitted by an emitting end and does not pass through any node; the uplink reference spectrum acquisition module is further configured to determine a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected of the uplink and the first spectrum; the downlink reference spectrum acquisition module is configured to acquire a link model of the downlink for transmitting the optical signal to be detected at the first monitoring point, and determine a response characteristic of a transmission link of the optical signal to be detected of the downlink according to the link model; the downlink reference spectrum acquisition module is also used for acquiring a first spectrum; the first spectrum is a signal spectrum which is emitted by an emitting end and does not pass through any node; the downlink reference spectrum acquisition module is further configured to determine a reference spectrum according to the response characteristic of the transmission link of the to-be-detected optical signal of the downlink and the first spectrum.

In a second aspect, an embodiment of the present invention provides a method for detecting an optical signal-to-noise ratio, including: the detection device acquires an optical signal to be detected; the detection device acquires an optical power spectrum of the optical signal to be detected at a first monitoring point; the detection device acquires a link model of the optical signal transmission to be detected at the first monitoring point, and determines the response characteristic of the transmission link of the optical signal to be detected according to the link model; the detection device acquires a first spectrum; wherein the first spectrum is a signal spectrum emitted by an emitting end and not passing through any device; the detection device determines a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected and the first spectrum; and the detection device determines the optical signal-to-noise ratio of the optical signal to be detected on the first monitoring point according to the optical power spectrum of the optical signal to be detected and the reference spectrum.

In a first possible implementation manner of the second aspect, the acquiring, by the detecting device, a first spectrum includes: the detection device acquires a modulation format of the optical signal to be detected, and determines the first spectrum according to the modulation format; or, the detection device determines whether the optical signal to be detected carries a pilot signal, and determines the first spectrum according to the pilot signal when determining that the optical signal to be detected carries the pilot signal.

With reference to the second aspect, or the first possible implementation manner of the second aspect, in a second possible implementation manner of the second aspect, the acquiring, by the detection device, the link model of the optical signal transmission to be detected at the first monitoring point includes: the detection device acquires a pre-stored link model for transmitting the optical signal to be detected from the first monitoring point; or, the detection device determines, at the first monitoring point, a link model for transmission of the optical signal to be detected according to a network node through which the optical signal to be detected passes acquired by a network side and a model of at least one network node stored in advance.

With reference to the second aspect, or the first or second possible implementation manner of the second aspect, in a third possible implementation manner of the second aspect, the acquiring, by the detecting device, the optical power spectrum of the optical signal to be detected at the first monitoring point includes: the detection device transmits local oscillator optical signals at a first frequency interval, and divides the transmitted local oscillator optical signals into a first local oscillator optical signal and a second local oscillator optical signal which are orthogonal to each other; the detection device divides the acquired optical signal to be detected into a first optical signal and a second optical signal which are orthogonal to each other, controls the directions of the first optical signal and the first local oscillator optical signal so as to enable the direction of the first optical signal to be consistent with the direction of the first local oscillator optical signal, and controls the directions of the second optical signal and the second local oscillator optical signal so as to enable the direction of the second optical signal to be the same as the direction of the second local oscillator optical signal; the detection device mixes the first optical signal with the first local oscillator optical signal to obtain a first mixed frequency signal, and mixes the second optical signal with the second local oscillator optical signal to obtain a second mixed frequency signal; wherein the first mixing signal comprises at least two mutually orthogonal optical signals; the second mixing signal comprises at least two mutually orthogonal optical signals; the detection device detects the first mixing signal and the second mixing signal, obtains analog optical power signals of the first mixing signal and the second mixing signal, and converts the analog optical power signals into digital optical power signals; the detection device carries out first processing on the digital optical power signal to obtain an optical power spectrum of the optical signal to be detected; the first processing comprises Fast Fourier Transform (FFT), frequency spectrum splicing, power correction and coefficient compensation.

With reference to the second aspect, or any one of the first to third possible implementation manners of the second aspect, in a fourth possible implementation manner of the second aspect, the acquiring, by the detection device, an optical signal to be detected includes: the detection device acquires the optical signal to be detected in one-way transmission; or, the detection device obtains the optical signal to be detected transmitted by the uplink and the optical signal to be detected transmitted by the downlink.

With reference to the fourth possible implementation manner of the second aspect, in a fifth possible implementation manner of the second aspect, the determining, by the detection device, a link model of transmission of the optical signal to be detected at the first monitoring point, and according to the link model, a response characteristic of a transmission link of the optical signal to be detected includes: the detection device acquires a link model of the optical signal transmission to be detected transmitted by the uplink at the first monitoring point, and determines the response characteristic of the transmission link of the optical signal to be detected transmitted by the uplink according to the link model; or, the detection device obtains a link model of the optical signal transmission to be detected transmitted in the downlink from the first monitoring point, and determines the response characteristic of the transmission link of the optical signal to be detected transmitted in the downlink according to the link model; the determining, by the detection device, a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected and the first spectrum includes: the detection device determines the optical signal-to-noise ratio of the optical signal to be detected transmitted by the uplink on the first monitoring point according to the optical power spectrum of the optical signal to be detected transmitted by the uplink and the reference spectrum; or, the detection device determines the optical signal-to-noise ratio of the optical signal to be detected transmitted in the downlink at the first monitoring point according to the optical power spectrum of the optical signal to be detected transmitted in the downlink and the reference spectrum.

In a third aspect, an embodiment of the present invention provides a detection apparatus, including: the communication interface is used for acquiring an optical signal to be detected; the communication interface is further configured to acquire an optical power spectrum of the optical signal to be detected at a first monitoring point; the communication interface is further configured to acquire a link model of optical signal transmission to be detected at the first monitoring point; the processor is used for determining the response characteristic of the transmission link of the optical signal to be detected according to the link model acquired by the communication interface; the communication interface is further used for acquiring a first spectrum; the first spectrum is a signal spectrum which is transmitted by a transmitting terminal and does not pass through any network node; the processor is further configured to determine a reference spectrum according to the first spectrum acquired by the communication interface and response characteristics of a transmission link of the optical signal to be detected; the processor is further configured to determine an optical signal-to-noise ratio of the optical signal to be detected at the first monitoring point according to the reference spectrum and the optical power spectrum of the optical signal to be detected, which is acquired by the communication interface.

In a first possible implementation manner of the third aspect, the communication interface is specifically configured to acquire a modulation format of the optical signal to be detected, and determine the first spectrum according to the modulation format; or, the communication interface is specifically configured to determine whether the optical signal to be detected carries a pilot signal, and determine the first spectrum according to the pilot signal when it is determined that the optical signal to be detected carries the pilot signal.

With reference to the third aspect, or the first possible implementation manner of the third aspect, in a second possible implementation manner of the third aspect, the apparatus further includes: a memory; the memory is configured to pre-store a link model for optical signal transmission to be detected, or pre-store a model of at least one network node through which the optical signal to be detected passes during transmission; the communication interface, configured to acquire, at the first monitoring point, the link model of the optical signal transmission to be detected includes: the communication interface is specifically configured to obtain, at the first monitoring point, the link model of the optical signal transmission to be detected from the memory; or, the communication interface is specifically configured to determine, at the first monitoring point, a link model for transmission of the optical signal to be detected according to a network node through which the optical signal to be detected passes acquired by a network side and the model of the at least one network node stored in the memory.

With reference to the third aspect, or the first or second possible implementation manner of the third aspect, in a third possible implementation manner of the third aspect, the obtaining, by the communication interface, an optical power spectrum of the optical signal to be detected at the first monitoring point includes: the communication interface is specifically configured to transmit a local oscillator optical signal at a first frequency interval, and divide the transmitted local oscillator optical signal into a first local oscillator optical signal and a second local oscillator optical signal that are orthogonal to each other; dividing the acquired optical signal to be detected into a first optical signal and a second optical signal which are orthogonal to each other, controlling the directions of the first optical signal and the first local oscillator optical signal so as to enable the direction of the first optical signal to be consistent with the direction of the first local oscillator optical signal, and controlling the directions of the second optical signal and the second local oscillator optical signal so as to enable the direction of the second optical signal to be the same as the direction of the second local oscillator optical signal; mixing the first optical signal and the first local oscillator optical signal to obtain a first mixed frequency signal, and mixing the second optical signal and the second local oscillator optical signal to obtain a second mixed frequency signal; wherein the first mixing signal comprises at least two mutually orthogonal optical signals; the second mixing signal comprises at least two mutually orthogonal optical signals; detecting the first mixing signal and the second mixing signal, acquiring analog optical power signals of the first mixing signal and the second mixing signal, and converting the analog optical power signals into digital optical power signals; performing first processing on the digital optical power signal to obtain an optical power spectrum of the optical signal to be detected; the first processing comprises Fast Fourier Transform (FFT), frequency spectrum splicing, power correction and coefficient compensation.

With reference to the third aspect, or any one of the first to third possible implementation manners of the third aspect, in a fourth possible implementation manner of the third aspect, the obtaining, by the communication interface, an optical signal to be detected includes: the communication interface is specifically used for acquiring the optical signal to be detected in unidirectional transmission; or, the communication interface is specifically configured to acquire the optical signal to be detected transmitted by an uplink and the optical signal to be detected transmitted by a downlink.

With reference to the fourth possible implementation manner of the third aspect, in a fifth possible implementation manner of the third aspect, the communication interface is further configured to obtain, at the first monitoring point, a link model of optical signal transmission to be detected for the uplink transmission; the processor is further configured to determine, according to the link model of the optical signal transmission to be detected of the uplink transmission acquired by the communication interface, a response characteristic of a transmission link of the optical signal to be detected of the uplink transmission; the processor is further configured to determine a reference spectrum according to a response characteristic of a transmission link of the optical signal to be detected transmitted by the uplink and the first spectrum acquired by the communication interface; the communication interface is further configured to acquire, at the first monitoring point, a link model of optical signal transmission to be detected, where the optical signal transmission is to be detected, and the link model is transmitted in the downlink; the processor is further configured to determine, according to the link model of the optical signal transmission to be detected of the downlink transmission, which is obtained by the communication interface, a response characteristic of a transmission link of the optical signal to be detected of the downlink transmission; the processor is further configured to determine a reference spectrum according to a response characteristic of a transmission link of the optical signal to be detected transmitted in the downlink and the first spectrum acquired by the communication interface.

The embodiment of the invention provides a method and a device for detecting an optical signal-to-noise ratio, wherein the device comprises: the optical signal detection device comprises a signal acquisition unit, a coherent receiving unit, a reference spectrum acquisition unit and a spectrum analysis unit, wherein the signal acquisition unit is used for acquiring an optical signal to be detected, the coherent receiving unit is used for detecting the optical signal to be detected on a first monitoring point and acquiring an optical power spectrum of the optical signal to be detected, the reference spectrum acquisition unit is used for acquiring a link model and a first spectrum transmitted by the optical signal to be detected on the first monitoring point, determining the response characteristic of a transmission link of the optical signal to be detected according to the acquired link model, and further determining a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected and the first spectrum, so that the spectrum analysis unit determines the optical signal-to-noise ratio of the optical signal to be detected on the first monitoring point according to the optical power spectrum and. In this way, the reference spectrum adopted by the spectrum analysis unit when determining the osnr of the optical signal to be detected is determined according to the link model of the optical signal to be detected and the first spectrum, thereby reducing the osnr error of the optical signal to be detected.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a functional schematic diagram of a detection apparatus according to an embodiment of the present invention;

FIG. 2 is a functional diagram of a coherent receiving unit of the detecting apparatus shown in FIG. 1;

FIG. 3 is a functional diagram of another detecting device according to an embodiment of the present invention;

FIG. 4 is a functional diagram of a reference spectrum acquisition unit of the detection apparatus shown in FIG. 1;

fig. 5 is a schematic flowchart of a method for detecting an optical signal-to-noise ratio according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a detection apparatus according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The embodiment of the invention provides a device for detecting the optical signal-to-noise ratio, which comprises: signal acquisition section 101, coherent reception section 102, reference spectrum acquisition section 103, and spectrum analysis section 104. Wherein,

the signal acquiring unit 101 is configured to acquire an optical signal to be detected.

It should be noted that, the signal obtaining unit 101 obtains different optical signals to be detected according to different network systems.

Specifically, in a DWDM (Dense Wavelength Division Multiplexing) network system, the signal obtaining unit 101 is specifically configured to obtain the optical signal to be detected in unidirectional transmission.

The optical signal to be detected which is transmitted in the one-way mode is an optical signal transmitted on an optical fiber link.

In a network system having a bidirectional transmission signal in a single optical fiber, such as a PON (Passive optical network) network system, the signal obtaining unit 101 is specifically configured to obtain the optical signal to be detected transmitted in an uplink and the optical signal to be detected transmitted in a downlink.

The uplink refers to a link when an ONU (Optical Network Unit) sends a signal to an OLT (Optical line Terminal); the downlink refers to a link when the OLT transmits a signal to the ONU.

The coherent receiving unit 102 is configured to detect the optical signal to be detected at a first monitoring point, and acquire an optical power spectrum of the optical signal to be detected.

The first monitoring point is a point on the optical fiber link, wherein the signal transmitted by the transmitting end passes through at least one network node.

Further, the coherent receiving unit 102, as shown in fig. 2, includes: the optical module comprises a polarization control module 1021, a local oscillator laser module 1022, a first polarization beam splitting module 1023, a second polarization beam splitting module 1024, a first optical frequency mixing module 1025, a second optical frequency mixing module 1026, a photoelectric detection module 1027, an analog-to-digital conversion module 1028 and a digital signal processing module 1029.

The local oscillator laser module 1022 is configured to transmit a local oscillator optical signal at a first frequency interval.

The first polarization beam splitting module 1023 is configured to split the optical signal to be detected into a first optical signal and a second optical signal that are orthogonal to each other, and input the first optical signal and the second optical signal to the first optical mixing module 1025 and the second optical mixing module 1026, respectively.

The second polarization beam splitting module 1024 is configured to split the local oscillator optical signal into a first local oscillator optical signal and a second local oscillator optical signal that are orthogonal to each other, and input the first local oscillator optical signal and the second local oscillator optical signal to the first optical frequency mixing module 1025 and the second optical frequency mixing module 1026 respectively.

The polarization control module 1021 is configured to control the first optical signal and the first local oscillator optical signal so that directions of the first optical signal and the first local oscillator optical signal are the same, and control the second optical signal and the second local oscillator optical signal so that directions of the second optical signal and the second local oscillator optical signal are the same.

The first optical frequency mixing module 1025 is configured to mix the first optical signal and the first local oscillator optical signal to obtain a first frequency mixing signal, and input the first frequency mixing signal to the photodetection module 1027. Wherein the first mixing signal comprises at least two mutually orthogonal optical signals.

The second optical frequency mixing module 1026 is configured to mix the second optical signal and the second local oscillator optical signal to obtain a second frequency mixing signal, and input the second frequency mixing signal to the photodetection module. Wherein the second mixing signal comprises at least two mutually orthogonal optical signals.

The photodetection module 1027 is configured to detect the first mixing signal and the second mixing signal, obtain an analog optical power signal of the first mixing signal and the second mixing signal, and input the analog optical power signal to the analog-to-digital conversion module 1028.

The analog-to-digital conversion module 1028 is configured to convert the analog optical power signal into a digital optical power signal, and input the digital optical power signal to the digital signal processing module 1029;

the digital signal processing module 1029 is configured to perform a first processing on the digital optical power signal to obtain an optical power spectrum of the optical signal to be detected.

Wherein the first processing includes Fast Fourier Transform (FFT), spectrum splicing, power correction, and coefficient compensation.

Specifically, in the DWDM network system, the local oscillator laser module 1022 changes the carrier frequency by a certain step length, and transmits the local oscillator optical signal by the changed carrier frequency; the first polarization beam splitting module 1023 splits the optical signal to be detected, which is transmitted in one direction, into a first optical signal and a second optical signal which are orthogonal to each other, and sends the first optical signal and the second optical signal to the first optical mixing module 1025 and the second optical mixing module 1026 respectively; the second polarization beam splitting module 1024 divides the local oscillation optical signal emitted by the local oscillation laser module 1022 into a first local oscillation optical signal and a second local oscillation optical signal which are orthogonal to each other, and respectively sends the first local oscillation optical signal and the second local oscillation optical signal to the first optical frequency mixing module 1025 and the second optical frequency mixing module 1026; the polarization control module 1021 controls the directions of the first optical signal and the first local oscillator optical signal so that the direction of the first optical signal is the same as the direction of the first local oscillator optical signal, and controls the directions of the second optical signal and the second local oscillator optical signal so that the direction of the second optical signal is the same as the direction of the second local oscillator optical signal; the first optical frequency mixing module 1025 performs frequency mixing on the received first optical signal and the first local oscillator optical signal to obtain at least two optical signals with orthogonal phases, and sends the at least two optical signals with orthogonal phases to each of the photoelectric detection modules 1027; the second optical frequency mixing module 1026 mixes the received second optical signal with a second local oscillator optical signal to obtain at least two optical signals with orthogonal phases, and sends the at least two optical signals with orthogonal phases to each of the photoelectric detection modules 1027; the photodetection module 1027 detects the received signal, determines an analog optical power signal of the received signal, and sends the calculated analog optical power signal of the received signal to the analog-to-digital conversion module 1028; the analog-to-digital conversion module 1028 converts the input analog optical power signal to obtain a digital optical power signal of the optical signal, and inputs the obtained digital optical power signal to the digital signal processing module 1029; the digital signal processing module 1029 performs FFT, spectrum splicing, power correction and coefficient compensation on the received digital optical power signal to obtain an optical power spectrum of the optical signal to be detected, which is transmitted unidirectionally.

It should be noted that, in a network system having a single optical fiber with bidirectional transmission signals, the method for the coherent receiving unit 102 to obtain the optical power spectrum of the optical signal to be detected of the uplink and the optical power spectrum of the optical signal to be detected of the downlink at the first monitoring point is similar to the method for the coherent receiving unit 102 to obtain the optical power spectrum of the optical signal to be detected of the unidirectional transmission at the first monitoring point in the DWDM system, and details of the method are not repeated herein.

The reference spectrum obtaining unit 103 is configured to obtain a link model of the optical signal transmission to be detected at the first monitoring point, and determine a response characteristic of a transmission link of the optical signal to be detected according to the link model.

The link model is a set of all network nodes passed by the optical signal to be detected during transmission.

Further, the detection device, as shown in fig. 3, further includes: and a memory unit 105.

The storage unit 105 is configured to store a link model for transmitting the optical signal to be detected in advance;

or, a model of at least one network node through which the optical signal to be detected passes during transmission is stored in advance.

It should be noted that, according to different network systems, the reference spectrum acquiring unit 103 acquires different link models for optical signal transmission to be detected at the first monitoring point, specifically as follows:

in the DWDM network system, the reference spectrum obtaining unit 103 is configured to obtain, at the first monitoring point, a link model for transmitting the optical signal to be detected in unidirectional transmission, and determine, according to the link model, a response characteristic of a transmission link of the optical signal to be detected in unidirectional transmission.

Specifically, in the DWDM network system, when the reference spectrum obtaining unit 103 obtains the link model of the optical signal transmission to be detected in the unidirectional transmission at the first monitoring point, the obtaining method is different for different parameter configurations of the DWDM network system, and specifically, the method is as follows:

the reference spectrum obtaining unit 103 is specifically configured to determine, at the first monitoring point, a link model for transmission of the optical signal to be detected according to the network node through which the optical signal to be detected passes obtained by the network side and the model of the at least one network node stored in the storage unit 105.

That is to say, when the parameters of the DWDM network system are configured in a dynamic configuration, before transmitting optical signals with different wavelengths, the transmitting end needs to add different optical labels to the optical signals with different wavelengths in a coding manner, and for an optical signal with one wavelength, the network side needs to decode and re-encode the optical label to generate a new optical label when passing through each network node.

Therefore, the network side generates information of each network node through which an optical signal with a wavelength is transmitted from the transmitting end according to the decoding and re-encoding information of the optical signal with a wavelength at each network node, and feeds back the information of each network node through which the optical signal with a wavelength is transmitted from the transmitting end to the reference spectrum obtaining unit 103, that is, feeds back the information of each network node through which the optical signal to be detected which is transmitted in a unidirectional manner is transmitted from the transmitting end to the reference spectrum obtaining unit 103. At this time, the reference spectrum obtaining unit 103 determines, at the first monitoring point, each network node through which the received optical signal to be detected transmitted in the unidirectional manner passes and the number of each network node according to information of each network node through which the received optical signal to be detected transmitted in the unidirectional manner passes, so as to obtain, in the storage unit 105, a model of each network node through which the optical signal to be detected transmitted in the unidirectional manner passes according to the number of each network node and each network node, further determine a link model of the optical signal to be detected transmitted in the unidirectional manner according to information of each network node and the obtained model of each network node, and determine a change of the signal spectrum of the optical signal to be detected transmitted in the unidirectional manner when the optical signal to be detected passes through each network node according to the link model of the optical signal to be detected transmitted in the unidirectional manner, so as to determine a change of the signal spectrum of the optical signal to be detected passing through each Response characteristics of a transmission link for optical signals.

It should be noted that, when the parameters of the DWDM network system are configured to be dynamically configured, the reference spectrum obtaining unit 103 may also obtain a link model of the optical signal transmission to be detected in unidirectional transmission according to other methods, which is not limited in the present invention.

Or, the reference spectrum obtaining unit 103 is specifically configured to obtain, at the first monitoring point, the link model of the optical signal transmission to be detected from the storage unit 105.

That is, when the parameters of the DWDM network system are configured in a fixed configuration, the network node through which the unidirectionally transmitted optical signal to be detected passes before the first monitoring point is fixed, the reference spectrum acquisition unit 103 may store in advance a link model through which the unidirectionally transmitted optical signal to be detected passes before the first monitoring point in the storage unit 105, so as to directly obtain the link model of the optical signal transmission to be detected of the unidirectional transmission from the storage unit 105 after obtaining the modulation format of the optical signal transmission to be detected of the unidirectional transmission, and determines the change of signal spectrum when the optical signal to be detected which is transmitted in one way passes through each network node according to the link model of the optical signal to be detected which is transmitted in one way, therefore, the response characteristic of the transmission link of the optical signal to be detected which is transmitted in a unidirectional mode is determined according to the signal spectrum change of the optical signal to be detected passing through each network node.

As an example, assuming that there are 3 network nodes through which the Optical signal to be detected transmitted in the unidirectional manner passes before the first monitoring point, each of the network nodes is a first ROADM (Reconfigurable Optical Add-drop Multiplexer), a second ROADM and an Optical signal amplifier, and the sequence of the network nodes through which the Optical signal to be detected transmitted in the unidirectional manner passes before the first monitoring point is the first ROADM, the Optical signal amplifier and the second ROADM, the storage unit 105 stores in advance that the Optical signal to be detected transmitted in the unidirectional manner passes through the first ROADM, the Optical signal amplifier and the link model of the second ROADM in sequence before the first monitoring point, so that after the modulation format of the Optical signal to be detected transmitted in the unidirectional manner is obtained, the link models of the Optical signal to be detected transmitted in the unidirectional manner passes through the first ROADM, the Optical signal amplifier and the second ROADM in sequence before the first monitoring point are directly obtained from the storage unit 105, and determining the change of the signal spectrum of the optical signal to be detected which is transmitted in the unidirectional mode when the optical signal to be detected passes through the first ROADM, the optical signal amplifier and the second ROADM according to the link model of the optical signal to be detected which is transmitted in the unidirectional mode, so that the response characteristic of the transmission link of the optical signal to be detected which is transmitted in the unidirectional mode is determined according to the change of the signal spectrum of the optical signal to be detected which passes through the first ROADM, the optical signal amplifier and the second ROADM.

Further, in a network system having a bidirectional transmission signal in a single optical fiber, the reference spectrum acquiring unit 103, as shown in fig. 4, includes: an uplink reference spectrum obtaining module 1031 and a downlink reference spectrum obtaining module 1032.

The uplink reference spectrum obtaining module 1031 is configured to obtain, at the first monitoring point, a link model of optical signal transmission to be detected transmitted in the uplink transmission, and determine, according to the link model, a response characteristic of a transmission link of the optical signal to be detected transmitted in the uplink transmission.

Specifically, the method for acquiring the link model of the optical signal transmission to be detected transmitted in the uplink transmission by the uplink reference spectrum acquisition module 1031, and determining the response characteristic of the transmission link of the optical signal to be detected in the uplink transmission according to the link model is similar to the method for acquiring the link model of the optical signal transmission to be detected in the unidirectional transmission in the DWDM network system, and determining the response characteristic of the transmission link of the optical signal to be detected in the unidirectional transmission according to the link model, and the details are not repeated herein.

The downlink reference spectrum obtaining module 1032 is configured to obtain, at the first monitoring point, a link model of the optical signal transmission to be detected transmitted in the downlink transmission, and determine, according to the link model, a response characteristic of a transmission link of the optical signal to be detected transmitted in the downlink transmission.

Specifically, the method for acquiring the link model of the optical signal transmission to be detected transmitted in the downlink transmission by the downlink reference spectrum acquisition module 1032 and determining the response characteristic of the transmission link of the optical signal to be detected transmitted in the downlink transmission according to the link model is similar to the method for acquiring the link model of the optical signal transmission to be detected in the unidirectional transmission in the DWDM network system and determining the response characteristic of the transmission link of the optical signal to be detected in the unidirectional transmission according to the link model, and the description of the method is omitted here.

The reference spectrum acquiring unit 103 is further configured to acquire a first spectrum.

The first spectrum is a signal spectrum which is emitted by an emitting end and does not pass through any node.

Specifically, in the DWDM network system, if only one modulation format of the optical signal to be detected is transmitted from the transmitting end, the reference spectrum acquiring unit 103 directly acquires the first spectrum.

If the modulation format of the optical signal to be detected emitted by the emitting end is at least one, the reference spectrum obtaining unit 103 obtains the first spectrum by the following methods.

In the first method, the reference spectrum obtaining unit 103 is specifically configured to obtain a modulation format of the optical signal to be detected, and determine the first spectrum according to the modulation format.

And the modulation format is a transmission format adopted during the transmission of the unidirectionally transmitted optical signal to be detected.

That is to say, the reference spectrum acquiring unit 103 acquires the optical signal to be detected in unidirectional transmission at the first monitoring point, and uses the acquired optical signal to be detected in unidirectional transmission as its own input signal, the neural network in the reference spectrum acquiring unit 103 extracts characteristic parameters in the input signal, for example, extracts time domain characteristics of the signal, the time domain characteristics of which include the instantaneous amplitude, instantaneous phase or histogram of instantaneous frequency or other statistical parameters of the signal, then forms an input vector according to the extracted characteristic parameter sample, and uses the input vector as the input of the neural network, and further trains the network according to a certain neural network function, and when the training step number, the training error, the training time or the training gradient value reach a preset threshold value, the training is automatically terminated, and returns to the trained neural network, and matching the trained neural network, that is, comparing the output of the trained neural network with a pre-stored sample, finding out a sample most similar to the output of the trained neural network by using a minimum mean square error criterion, and using the sample as a modulation format of the optical signal to be detected in the unidirectional transmission acquired by the reference spectrum acquisition unit 103, thereby determining that the signal spectrum of the optical signal to be detected in the unidirectional transmission does not pass through any network node, namely the first spectrum.

In the second method, the reference spectrum obtaining unit 103 is specifically configured to determine whether the optical signal to be detected carries a pilot signal, and determine the first spectrum according to the pilot signal when it is determined that the optical signal to be detected carries the pilot signal.

That is to say, the reference spectrum acquiring unit 103 determines whether the optical signal to be detected that is transmitted unidirectionally carries a pilot signal at the first monitoring point, and determines the modulation format of the optical signal to be detected that is transmitted unidirectionally according to the frequency of the pilot signal when it is determined that the optical signal to be detected that is transmitted unidirectionally carries the pilot signal, so as to determine that the signal spectrum of the optical signal to be detected that is transmitted unidirectionally does not pass through any network node, that is, the first spectrum.

It should be noted that the transmitting end may transmit optical signals with different modulation formats, and before transmitting the optical signals, pilot signals with different frequencies are carried in the optical signals with different modulation formats, so that the reference spectrum obtaining unit 103 may determine the modulation format of the optical signal to be detected that is transmitted in a unidirectional manner according to the frequency of the carried pilot signal.

It should be noted that, the reference spectrum obtaining unit 103 may also obtain the modulation format of the optical signal to be detected in the unidirectional transmission according to other methods, which is not limited in the present invention.

It should be noted that, in a network system having a single optical fiber with bidirectional transmission signals, a method for the uplink reference spectrum obtaining unit 1031 and the downlink reference spectrum obtaining unit 1032 to obtain the first spectrum respectively is similar to a method for the reference spectrum obtaining unit 103 to obtain the first spectrum in the DWDM network system, and details of the present invention are not repeated herein.

The reference spectrum obtaining unit 103 is further configured to determine a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected and the first spectrum.

Specifically, in the DWDM network system, the reference spectrum obtaining unit 103 is specifically configured to determine the reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected that is transmitted unidirectionally and the first spectrum.

That is to say, after determining the response characteristic of the transmission link of the optical signal to be detected in unidirectional transmission and acquiring the first spectrum, the reference spectrum acquisition unit 103 multiplies the waveform generated by the response characteristic of the transmission link of the optical signal to be detected in unidirectional transmission by the waveform of the first spectrum, so as to obtain a new waveform, that is, the determination reference spectrum.

In a network system having a single optical fiber with bidirectional transmission signals, the uplink reference spectrum obtaining module 1031 is further configured to determine a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected transmitted by the uplink and the first spectrum.

That is to say, after determining the response characteristic of the transmission link of the optical signal to be detected transmitted in the uplink and acquiring the first spectrum, the uplink reference spectrum acquisition unit 1031 multiplies the waveform generated by the response characteristic of the transmission link of the optical signal to be detected transmitted in the uplink by the waveform of the first spectrum, so as to obtain a new waveform, that is, the new waveform is the determination reference spectrum.

The downlink reference spectrum obtaining module 1032 is further configured to determine a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected transmitted in the downlink and the first spectrum.

That is to say, after determining the response characteristic of the transmission link of the optical signal to be detected transmitted in the downlink and acquiring the first spectrum, the downlink reference spectrum acquiring unit 1032 multiplies the waveform generated by the response characteristic of the transmission link of the optical signal to be detected transmitted in the downlink by the waveform of the first spectrum, so as to obtain a new waveform, that is, the new waveform is the determination reference spectrum.

The spectrum analysis unit 104 is configured to determine an optical signal-to-noise ratio of the optical signal to be detected at the first monitoring point according to the optical power spectrum of the optical signal to be detected and the reference spectrum.

Specifically, in the DWDM network system, the spectral analysis unit 104 determines the optical signal-to-noise ratio of the optical signal to be detected in the unidirectional transmission at the first monitoring point according to the optical power spectrum of the optical signal to be detected in the unidirectional transmission acquired by the coherent reception unit 102 and the reference spectrum determined by the reference spectrum acquisition unit 103, and the specific determination method includes the following steps:

step one, the spectrum analysis unit 104 selects two bands with different center wavelengths and the same bandwidth from the optical power spectrum of the optical signal to be detected of the unidirectional transmission acquired by the coherent reception unit 102, that is, selects two bands with different center frequencies and the same bandwidth, and respectively marks them as a first band and a second band, and calculates a power value P (BW) of the first band₁) And power value P (BW) of the second band₂) (ii) a A third band having the same center frequency and bandwidth as the first band and a fourth band having the same center frequency and bandwidth as the second band are selected from the reference spectrum determined by the reference spectrum obtaining unit 103, and a power value R (BW) of the third band is calculated₁) And a power value R (BW) of a fourth band₂)。

Step two, the spectral analysis unit 104 calculates a power value P (BW) of the first band of the optical signal to be detected transmitted unidirectionally according to the calculated BW₁) With the power value P (BW) of the second band₂) Is compared with the power value R (BW) of the third band of the reference spectrum₁) And a power value R (BW) of a fourth band₂) The difference value is divided, and the ratio of the total power of the optical signal to be detected which is transmitted in a single direction to the total power of the reference spectrum is calculated, namely:

the spectral analysis unit 104 is based on a formulaAnd calculating the ratio of the total power of the optical signal to be detected in unidirectional transmission to the total power of the reference spectrum.

It should be noted that, when a ratio of a total power of the optical signal to be detected in the unidirectional transmission to a total power of the reference spectrum is obtained, it is assumed that noise in two bands with the same bandwidth is flat, that is, noise power in two bands with the same bandwidth is the same.

Thirdly, the spectrum analysis unit 104 determines the actual signal total power of the unidirectionally transmitted optical signal to be detected according to the multiplication of the total power of the unidirectionally transmitted optical signal to be detected and the ratio of the total power of the unidirectionally transmitted optical signal to be detected and the total power of the reference spectrum; and determining the actual noise total power of the optical signal to be detected in the unidirectional transmission according to the total power of the reference spectrum and the ratio of the total power of the optical signal to be detected in the unidirectional transmission to the total power of the reference spectrum. Namely:

the spectral analysis unit 104 is based on the formula S_eAnd KR is used for acquiring the signal power value of the optical signal to be detected which is transmitted in the unidirectional mode.

According to formula N_eAnd acquiring the noise power value of the unidirectional transmission optical signal to be detected.

It should be noted that the total power P of the optical signal to be detected in the unidirectional transmission is obtained by integrating the obtained optical power spectrum of the optical signal to be detected in the unidirectional transmission by the spectrum analysis unit 104; the total power R of the reference spectrum is obtained by integrating the acquired reference spectrum by the spectrum analysis unit 104.

And fourthly, the spectral analysis unit 104 determines the optical signal to noise ratio of the optical signal to be detected which is transmitted in one way according to the ratio of the total power of the actual signal of the optical signal to be detected which is transmitted in one way to the total power of the actual noise of the optical signal to be detected which is transmitted in one way. Namely:

the spectral analysis unit 104 is based on a formulaAnd calculating the optical signal-to-noise ratio of the optical signal to be detected which is transmitted in the one-way mode on the first monitoring point.

In addition, P (BW)₁) The power value of the first wave band of the optical signal to be detected which is transmitted in a single direction; p (BW)₂) Is a sheetA power value of a second waveband of the transmitted optical signal to be detected; r (BW)₁) A power value for a third band of the reference spectrum; r (BW)₂) Is the power value of the fourth band of the reference spectrum; k is the ratio of the total power of the optical signal to be detected in one-way transmission to the total power of the reference spectrum; s_eThe actual signal power value of the optical signal to be detected is transmitted in a single direction; n is a radical of_eThe actual noise power value of the optical signal to be detected is transmitted in a single direction; BW is the channel bandwidth; BW (Bandwidth)_0.1Is 0.1nm equivalent bandwidth.

It should be noted that, the method for determining the optical signal-to-noise ratio of the optical signal to be detected in the unidirectional transmission by the spectrum analysis unit 104 according to the optical power spectrum of the optical signal to be detected in the unidirectional transmission and the reference spectrum may also be other methods, which is not limited in the present invention.

It should be noted that, when determining the optical signal-to-noise ratio of the optical signal to be detected which is transmitted in one direction at least one monitoring point, the detection device is provided at each monitoring point, and the detection device at each monitoring point can only determine the optical signal-to-noise ratio of the optical signal to be detected which is transmitted in one direction at the monitoring point.

It should be noted that, in a network system having a bidirectional transmission signal in a single optical fiber, the method for determining the optical signal-to-noise ratio of the optical signal to be detected transmitted in the uplink by the spectrum analysis unit 104 and the method for determining the optical signal-to-noise ratio of the optical signal to be detected transmitted in the downlink by the spectrum analysis unit 104 are similar to the method for determining the optical signal-to-noise ratio of the optical signal to be detected transmitted in the unidirectional transmission in the DWDM network system by the spectrum analysis unit 104, and the description of the method is omitted herein.

The embodiment of the invention provides a device for detecting the optical signal-to-noise ratio, which comprises: the optical signal detection device comprises a signal acquisition unit, a coherent receiving unit, a reference spectrum acquisition unit and a spectrum analysis unit, wherein the signal acquisition unit is used for acquiring an optical signal to be detected, the coherent receiving unit is used for detecting the optical signal to be detected on a first monitoring point and acquiring an optical power spectrum of the optical signal to be detected, the reference spectrum acquisition unit is used for acquiring a link model and a first spectrum transmitted by the optical signal to be detected on the first monitoring point, determining the response characteristic of a transmission link of the optical signal to be detected according to the acquired link model, and further determining a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected and the first spectrum, so that the spectrum analysis unit determines the optical signal-to-noise ratio of the optical signal to be detected on the first monitoring point according to the optical power spectrum and. In this way, the reference spectrum adopted by the spectrum analysis unit when determining the osnr of the optical signal to be detected is determined according to the link model of the optical signal to be detected and the first spectrum, thereby reducing the osnr error of the optical signal to be detected.

An embodiment of the present invention provides a method for detecting an optical signal-to-noise ratio, as shown in fig. 5, including:

101. the detection device acquires an optical signal to be detected.

It should be noted that, the detection device obtains different optical signals to be detected according to different network systems.

Specifically, in the DWDM network system, the detection device obtains the optical signal to be detected in unidirectional transmission.

In a network system having a bidirectional transmission signal in a single optical fiber, for example, in a PON network system, a detection apparatus acquires the optical signal to be detected transmitted in an uplink and the optical signal to be detected transmitted in a downlink.

102. The detection device detects the optical signal to be detected on a first monitoring point and obtains an optical power spectrum of the optical signal to be detected.

Further, the detection device transmits the local oscillator optical signal at a first frequency interval, and divides the transmitted local oscillator optical signal into a first local oscillator optical signal and a second local oscillator optical signal which are orthogonal to each other; dividing the acquired optical signal to be detected into a first optical signal and a second optical signal which are orthogonal to each other, controlling the directions of the first optical signal and the first local oscillator optical signal so as to enable the direction of the first optical signal to be consistent with the direction of the first local oscillator optical signal, and controlling the directions of the second optical signal and the second local oscillator optical signal so as to enable the direction of the second optical signal to be the same as the direction of the second local oscillator optical signal; mixing the first optical signal and the first local oscillator optical signal to obtain a first mixing signal, and mixing the second optical signal and the second local oscillator optical signal to obtain a second mixing signal; detecting the first mixing signal and the second mixing signal, acquiring analog optical power signals of the first mixing signal and the second mixing signal, and converting the analog optical power signals into digital optical power signals; and finally, performing first processing on the digital optical power signal to obtain an optical power spectrum of the optical signal to be detected.

Wherein the first mixing signal comprises at least two mutually orthogonal optical signals; the second mixing signal comprises at least two mutually orthogonal optical signals. The first processing comprises FFT transformation, frequency spectrum splicing, power correction and coefficient compensation.

Specifically, in the DWDM network system, the detection device changes the carrier frequency by a certain step length, transmits the local oscillation optical signal by the changed carrier frequency, and divides the transmitted local oscillation optical signal into a first local oscillation optical signal and a second local oscillation optical signal which are orthogonal to each other; dividing the acquired optical signal to be detected in unidirectional transmission into a first optical signal and a second optical signal which are orthogonal to each other, and simultaneously controlling the directions of the first optical signal and the first local oscillator optical signal so that the direction of the first optical signal is the same as that of the first local oscillator optical signal, and controlling the directions of the second optical signal and the second local oscillator optical signal so that the direction of the second optical signal is the same as that of the second local oscillator optical signal; and finally, carrying out FFT (fast Fourier transform), frequency spectrum splicing, power correction and coefficient compensation on the obtained digital optical power signal to obtain an optical power spectrum of the optical signal to be detected in one-way transmission.

It should be noted that, in a network system having a single optical fiber with bidirectional transmission signals, a method for acquiring, by a detection device, an optical power spectrum of an optical signal to be detected in an uplink and an optical power spectrum of an optical signal to be detected in a downlink at a first monitoring point is similar to a method for acquiring, by a detection device, an optical power spectrum of an optical signal to be detected in a unidirectional transmission at a first monitoring point in a DWDM system, and the description of the method is omitted here.

103. The detection device acquires the link model of the optical signal transmission to be detected at the first monitoring point, and determines the response characteristic of the transmission link of the optical signal to be detected according to the link model.

It should be noted that, according to different network systems, the detection apparatus obtains different link models for transmission of the optical signal to be detected at the first monitoring point, specifically as follows:

in a DWDM network system, a detection device acquires a link model of the unidirectional transmission of the optical signal to be detected at the first monitoring point, and determines the response characteristic of a transmission link of the unidirectional transmission optical signal to be detected according to the link model.

Specifically, in the DWDM network system, when the detection apparatus obtains the link model of the unidirectional transmission optical signal transmission to be detected at the first monitoring point, the obtaining method is different for different parameter configurations of the DWDM network system, specifically as follows:

and the detection device determines a link model for transmitting the optical signal to be detected at the first monitoring point according to the network node through which the optical signal to be detected passes and the pre-stored model of the at least one network node, which are acquired by the network side.

Therefore, the network side generates information of each network node through which the optical signal with one wavelength is transmitted from the transmitting end according to the decoding and recoding information of the optical signal with one wavelength at each network node, and feeds back the information of each network node through which the optical signal with one wavelength is transmitted from the transmitting end to the detecting device, namely feeds back the information of each network node through which the optical signal to be detected which is transmitted in a unidirectional way is transmitted from the transmitting end to the detecting device. At this time, the detection device determines the number of each network node and each network node through which the optical signal to be detected which is transmitted in the unidirectional direction passes according to the information of each network node through which the received optical signal to be detected which is transmitted in the unidirectional direction passes on the first monitoring point, so as to obtain a model of each network node through which the optical signal to be detected which is transmitted in the unidirectional direction passes from at least one pre-stored model of the network node according to the number of each network node and each network node, further determine a link model of the optical signal to be detected which is transmitted in the unidirectional direction according to the information of each network node and the obtained model of each network node, determine the change of the signal spectrum when the optical signal to be detected which is transmitted in the unidirectional direction passes through each network node according to the link model of the optical signal to be detected which is transmitted in the unidirectional direction, and determine the change of the signal spectrum when the optical signal to be detected passes The response characteristics of the transmission link of the optical signal are detected.

It should be noted that, when the parameters of the DWDM network system are configured to be dynamically configured, the detection apparatus may further obtain the link model of the optical signal transmission to be detected in the unidirectional transmission according to other methods, which is not limited in the present invention.

And the detection device acquires a prestored link model for transmitting the optical signal to be detected from the first monitoring point.

That is to say, when the parameters of the DWDM network system are configured in a fixed configuration, the network node through which the optical signal to be detected that is transmitted in the unidirectional transmission passes before the first monitoring point is fixed, so the detection apparatus may store in advance the link model through which the optical signal to be detected that is transmitted in the unidirectional transmission passes before the first monitoring point, and thus directly obtain the pre-stored link model of the optical signal to be detected that is transmitted in the unidirectional transmission after obtaining the modulation format of the optical signal to be detected that is transmitted in the unidirectional transmission.

And determining the change of the signal spectrum of the optical signal to be detected in the unidirectional transmission when the optical signal to be detected in the unidirectional transmission passes through each network node according to the link model of the optical signal to be detected in the unidirectional transmission, so as to determine the response characteristic of the transmission link of the optical signal to be detected in the unidirectional transmission according to the signal spectrum change of the optical signal to be detected passing through each network node.

As an example, it is assumed that there are 3 network nodes through which the unidirectionally transmitted Optical signal to be detected passes before the first monitoring point, namely a first ROADM (Reconfigurable Optical Add-drop Multiplexer), a second ROADM and an Optical signal amplifier, and the order of the network nodes passed by the optical signal to be detected in the unidirectional transmission before the first monitoring point is a first ROADM, an optical signal amplifier and a second ROADM, the detection device stores in advance the link model of the optical signal to be detected which is transmitted in one way and passes through the first ROADM, the optical signal amplifier and the second ROADM in sequence before the first monitoring point, therefore, after the modulation format of the unidirectional transmission optical signal to be detected is obtained, the prestored link model of the unidirectional transmission optical signal to be detected sequentially passes through the first ROADM, the optical signal amplifier and the second ROADM before the first monitoring point is directly determined as the link model of the unidirectional transmission optical signal to be detected passing through before the first monitoring point.

And determining the change of the signal spectrum of the optical signal to be detected which is transmitted in the unidirectional mode when the optical signal to be detected passes through the first ROADM, the optical signal amplifier and the second ROADM according to the link model of the optical signal to be detected which is transmitted in the unidirectional mode, so that the response characteristic of the transmission link of the optical signal to be detected which is transmitted in the unidirectional mode is determined according to the change of the signal spectrum of the optical signal to be detected which passes through the first ROADM, the optical signal amplifier and the second ROADM.

In the PON network system, the detection apparatus obtains, at the first monitoring point, a link model of optical signal transmission to be detected transmitted in the uplink transmission, and determines, according to the link model, a response characteristic of a transmission link of the optical signal to be detected transmitted in the uplink transmission.

Specifically, the method for acquiring the link model of the optical signal transmission to be detected transmitted in the uplink transmission by the detection device and determining the response characteristic of the transmission link of the optical signal to be detected transmitted in the uplink transmission according to the link model is similar to the method for acquiring the link model of the optical signal transmission to be detected in the unidirectional transmission in the DWDM network system and determining the response characteristic of the transmission link of the optical signal to be detected in the unidirectional transmission according to the link model, and the details are not repeated herein.

Or, the detection apparatus obtains a link model of the optical signal transmission to be detected transmitted in the downlink from the first monitoring point, and determines the response characteristic of the transmission link of the optical signal to be detected transmitted in the downlink according to the link model.

Specifically, the method for acquiring the link model of the optical signal transmission to be detected in downlink transmission by the detection device and determining the response characteristic of the transmission link of the optical signal to be detected in downlink transmission according to the link model is similar to the method for acquiring the link model of the optical signal transmission to be detected in unidirectional transmission in the DWDM network system and determining the response characteristic of the transmission link of the optical signal to be detected in unidirectional transmission according to the link model, and the details are not repeated herein.

104. The detection device acquires a first spectrum.

Specifically, in the DWDM network system, if only one modulation format of the optical signal to be detected is transmitted from the transmitting end, the detecting device directly acquires the first spectrum.

If the modulation format of the optical signal to be detected emitted by the emitting end is at least one, the method for acquiring the first spectrum by the detection device includes the following methods.

In a first method, a detection device obtains a modulation format of the optical signal to be detected, and determines the first spectrum according to the modulation format.

That is, the detecting device collects the optical signal to be detected in unidirectional transmission on the first monitoring point, and uses the collected optical signal to be detected in unidirectional transmission as its own input signal, the neural network in the detecting device firstly extracts characteristic parameters from the input signal, for example, extracts the time domain characteristics of the signal, the time domain characteristics of which include the instantaneous amplitude, instantaneous phase or histogram of instantaneous frequency or other statistical parameters of the signal, then forms an input vector according to the extracted characteristic parameter sample, and uses the input vector as the input of the neural network, and further trains the network according to a certain neural network function, when the training step number, training error, training time or training gradient value reach the preset threshold value, the training is automatically terminated, and returns to the trained neural network, and matches the trained neural network, the output of the trained neural network is compared with a prestored sample, a sample which is most similar to the output of the trained neural network is found out by adopting a minimum mean square error criterion, and the sample is used as a modulation format of the optical signal to be detected which is acquired by the detection device and transmitted in one direction, so that the signal spectrum of the optical signal to be detected which is transmitted in one direction and does not pass through any network node is determined, namely the first spectrum.

In the second method, the detection device determines whether the optical signal to be detected carries a pilot signal, and determines the first spectrum according to the pilot signal when determining that the optical signal to be detected carries the pilot signal.

That is to say, the detection device determines whether the optical signal to be detected which is transmitted unidirectionally carries a pilot signal at the first monitoring point, and determines the modulation format of the optical signal to be detected which is transmitted unidirectionally according to the frequency of the pilot signal when it is determined that the optical signal to be detected which is transmitted unidirectionally carries the pilot signal, so as to determine that the signal spectrum of the optical signal to be detected which is transmitted unidirectionally does not pass through any network node, that is, the first spectrum.

It should be noted that the transmitting end may transmit optical signals with different modulation formats, and before transmitting the optical signals, pilot signals with different frequencies are carried in the optical signals with different modulation formats, so that the detection apparatus may determine the modulation format of the optical signal to be detected in unidirectional transmission according to the frequency of the carried pilot signal.

It should be noted that the detection apparatus may also obtain the modulation format of the optical signal to be detected in the unidirectional transmission according to other methods, which is not limited in the present invention.

It should be noted that, in a network system having a single fiber with bidirectional transmission signals, the method for acquiring the first spectrum by the detection apparatus is similar to the method for acquiring the first spectrum by the detection apparatus in the DWDM network system, and the description of the present invention is omitted here.

105. And the detection device determines a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected and the first spectrum.

Specifically, in the DWDM network system, the detection device determines the reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected transmitted in the unidirectional direction and the first spectrum.

That is to say, after determining the response characteristic of the transmission link of the optical signal to be detected in unidirectional transmission and acquiring the first spectrum, the detection device multiplies the waveform generated by the response characteristic of the transmission link of the optical signal to be detected in unidirectional transmission by the waveform of the first spectrum, so as to obtain a new waveform, that is, the new waveform is the determination reference spectrum.

In a network system with bidirectional transmission signals in a single optical fiber, a detection device determines a reference spectrum according to the response characteristic of a transmission link of an optical signal to be detected transmitted by an uplink and the first spectrum.

That is to say, after determining the response characteristic of the transmission link of the optical signal to be detected transmitted by the uplink and acquiring the first spectrum, the detection device multiplies the waveform generated by the response characteristic of the transmission link of the optical signal to be detected transmitted by the uplink by the waveform of the first spectrum, so as to obtain a new waveform, that is, the determination reference spectrum.

Or, the detection device determines the reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected transmitted in the downlink and the first spectrum.

That is to say, after determining the response characteristic of the transmission link of the optical signal to be detected transmitted in the downlink and acquiring the first spectrum, the detection device multiplies the waveform generated by the response characteristic of the transmission link of the optical signal to be detected transmitted in the downlink by the waveform of the first spectrum, so as to obtain a new waveform, that is, the determination reference spectrum.

It should be noted that, the step 102 has no sequence with any one of the steps 103, 104, and 105, and the present invention is not limited thereto.

106. And the detection device determines the optical signal-to-noise ratio of the optical signal to be detected on the first monitoring point according to the optical power spectrum of the optical signal to be detected and the reference spectrum.

Specifically, in the DWDM network system, the detection device determines the optical signal-to-noise ratio of the optical signal to be detected in the unidirectional transmission at the first monitoring point according to the acquired optical power spectrum of the optical signal to be detected in the unidirectional transmission and the determined reference spectrum, and the specific determination method includes the following steps:

step one, the detection device selects two wave bands with different central wavelengths and the same bandwidth from the acquired optical power spectrum of the optical signal to be detected in the unidirectional transmission, namely selects two wave bands with different central frequencies and the same bandwidth, respectively records the two wave bands as a first wave band and a second wave band, and calculates a power value P (BW) of the first wave band₁) And power value P (BW) of the second band₂) (ii) a Selecting a third wave band with the same center frequency and bandwidth as the first wave band and a fourth wave band with the same center frequency and bandwidth as the second wave band from the determined reference spectrum, and calculating the power value R (BW) of the third wave band₁) And a power value R (BW) of a fourth band₂)。

Step two, the detection device calculates the power value P (BW) of the first wave band of the optical signal to be detected in one-way transmission₁) With the power value P (BW) of the second band₂) Is compared with the power value R (BW) of the third band of the reference spectrum₁) And a power value R (BW) of a fourth band₂) The difference value is divided, and the ratio of the total power of the optical signal to be detected which is transmitted in a single direction to the total power of the reference spectrum is calculated, namely:

the detection device is based on the formulaAnd calculating the ratio of the total power of the optical signal to be detected in unidirectional transmission to the total power of the reference spectrum.

Step three, the detection device multiplies the ratio of the total power of the optical signal to be detected which is transmitted in a single direction to the total power of the reference spectrum to determine the actual signal total power of the optical signal to be detected which is transmitted in a single direction; and determining the actual noise total power of the optical signal to be detected in the unidirectional transmission according to the total power of the reference spectrum and the ratio of the total power of the optical signal to be detected in the unidirectional transmission to the total power of the reference spectrum. Namely:

the detection device is based on formula S_eAnd KR is used for acquiring the signal power value of the optical signal to be detected which is transmitted in the unidirectional mode.

It should be noted that the total power P of the optical signal to be detected in the unidirectional transmission is obtained by integrating the optical power spectrum of the acquired optical signal to be detected in the unidirectional transmission by the detection device; the total power R of the reference spectrum is obtained by integrating the acquired reference spectrum by the detection device.

And fourthly, determining the optical signal-to-noise ratio of the unidirectionally transmitted optical signal to be detected by the detection device according to the ratio of the determined actual signal total power of the unidirectionally transmitted optical signal to be detected and the determined actual noise total power of the unidirectionally transmitted optical signal to be detected. Namely:

the detection device is based on the formulaAnd calculating the optical signal-to-noise ratio of the optical signal to be detected which is transmitted in the one-way mode on the first monitoring point.

In addition, P (BW)₁) The power value of the first wave band of the optical signal to be detected which is transmitted in a single direction; p (BW)₂) The power value of a second wave band of the optical signal to be detected which is transmitted in a single direction; r (BW)₁) A power value for a third band of the reference spectrum; r (BW)₂) Is the power value of the fourth band of the reference spectrum; k is the ratio of the total power of the optical signal to be detected in one-way transmission to the total power of the reference spectrum; s_eThe actual signal power value of the optical signal to be detected is transmitted in a single direction; n is a radical of_eThe actual noise power value of the optical signal to be detected is transmitted in a single direction; BW is the channel bandwidth; BW (Bandwidth)_0.1Is 0.1nm equivalent bandwidth.

It should be noted that, the method for determining the optical signal-to-noise ratio of the optical signal to be detected in the unidirectional transmission by the detection device according to the optical power spectrum and the reference spectrum of the optical signal to be detected in the unidirectional transmission may also be other methods, which is not limited in this invention.

It should be noted that, in a network system having a bidirectional transmission signal in a single optical fiber, the method for determining the optical signal-to-noise ratio of the optical signal to be detected transmitted in the uplink and the method for determining the optical signal-to-noise ratio of the optical signal to be detected transmitted in the downlink are similar to the method for determining the optical signal-to-noise ratio of the optical signal to be detected transmitted in the single optical fiber in the DWDM network system, and the description of the present invention is omitted here.

The embodiment of the invention provides a method for detecting an optical signal-to-noise ratio, wherein after a detection device acquires an optical signal to be detected, an optical power spectrum of the optical signal to be detected is acquired at a first monitoring point, a link model and a first spectrum for transmitting the optical signal to be detected are acquired at the first monitoring point, so that the response characteristic of a transmission link of the optical signal to be detected is determined according to the acquired link model, a reference spectrum is determined according to the response characteristic of the transmission link of the optical signal to be detected and the first spectrum, and finally the optical signal-to-noise ratio of the optical signal to be detected at the first monitoring point is determined according to the optical power spectrum of the optical signal to be detected and the reference spectrum. In this way, the reference spectrum adopted by the detection device when determining the osnr of the optical signal to be detected is determined according to the link model of the optical signal to be detected and the first spectrum, thereby reducing the osnr error of the optical signal to be detected.

An embodiment of the present invention provides a detection apparatus, as shown in fig. 6, including: a processor (processor)601, a communication Interface (Communications Interface)602, a memory (memory)603, and a communication bus 604; the processor 601, the communication interface 602, and the memory 603 complete communication with each other through the communication bus 604.

The processor 601 may be a central processing unit CPU or an application specific Integrated circuit asic or one or more Integrated circuits configured to implement embodiments of the present invention.

The memory 603 is used to store program code, which includes computer operating instructions. The memory 603 may comprise a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory. The processor 601 is used to call the program code in the memory 603. The method specifically comprises the following steps:

the communication interface 602 is configured to acquire an optical signal to be detected.

It should be noted that, the communication interface 602 obtains different optical signals to be detected according to different network systems.

Specifically, in the DWDM network system, the communication interface 602 is specifically configured to acquire the optical signal to be detected in unidirectional transmission.

In a network system having a bidirectional transmission signal in a single optical fiber, such as a PON network system, the communication interface 602 is specifically configured to acquire the optical signal to be detected transmitted in an uplink and the optical signal to be detected transmitted in a downlink.

The uplink refers to a link when the ONU sends a signal to the OLT; the downlink refers to a link when the OLT transmits a signal to the ONU.

The communication interface 602 is further configured to acquire an optical power spectrum of the optical signal to be detected at a first monitoring point.

Further, the communication interface 602 is specifically configured to transmit a local oscillator optical signal at a first frequency interval, and divide the transmitted local oscillator optical signal into a first local oscillator optical signal and a second local oscillator optical signal that are orthogonal to each other; dividing the acquired optical signal to be detected into a first optical signal and a second optical signal which are orthogonal to each other, controlling the directions of the first optical signal and the first local oscillator optical signal so as to enable the direction of the first optical signal to be consistent with the direction of the first local oscillator optical signal, and controlling the directions of the second optical signal and the second local oscillator optical signal so as to enable the direction of the second optical signal to be the same as the direction of the second local oscillator optical signal; mixing the first optical signal and the first local oscillator optical signal to obtain a first mixed frequency signal, and mixing the second optical signal and the second local oscillator optical signal to obtain a second mixed frequency signal; detecting the first mixing signal and the second mixing signal, acquiring analog optical power signals of the first mixing signal and the second mixing signal, and converting the analog optical power signals into digital optical power signals; and performing first processing on the digital optical power signal to obtain an optical power spectrum of the optical signal to be detected.

Specifically, in the DWDM network system, the communication interface 602 changes the carrier frequency by a certain step length, transmits the local oscillation optical signal by the changed carrier frequency, and divides the transmitted local oscillation optical signal into a first local oscillation optical signal and a second local oscillation optical signal which are orthogonal to each other; dividing the acquired optical signal to be detected in unidirectional transmission into a first optical signal and a second optical signal which are orthogonal to each other, and simultaneously controlling the directions of the first optical signal and the first local oscillator optical signal so that the direction of the first optical signal is the same as that of the first local oscillator optical signal, and controlling the directions of the second optical signal and the second local oscillator optical signal so that the direction of the second optical signal is the same as that of the second local oscillator optical signal; and finally, carrying out FFT (fast Fourier transform), frequency spectrum splicing, power correction and coefficient compensation on the obtained digital optical power signal to obtain an optical power spectrum of the optical signal to be detected in one-way transmission.

It should be noted that, in a network system having a single optical fiber with bidirectional transmission signals, the method for the communication interface 602 to obtain the optical power spectrum of the optical signal to be detected of the uplink and the optical power spectrum of the optical signal to be detected of the downlink at the first monitoring point is similar to the method for the communication interface 602 to obtain the optical power spectrum of the optical signal to be detected of the unidirectional transmission at the first monitoring point in the DWDM system, and the description of the method is omitted here.

The communication interface 602 is further configured to obtain, at the first monitoring point, a link model of optical signal transmission to be detected.

The memory 603 is further configured to store a link model of the optical signal transmission to be detected in advance.

It should be noted that, according to different network systems, the communication interface 602 obtains different link models for transmission of the optical signal to be detected at the first monitoring point, which is specifically as follows:

in the DWDM network system, the communication interface 602 is configured to obtain, at the first monitoring point, a link model of the unidirectional transmission of the optical signal to be detected.

Specifically, in the DWDM network system, when the communication interface 602 acquires the link model of the unidirectional transmission optical signal transmission to be detected at the first monitoring point, the acquisition method is different for different parameter configurations of the DWDM network system, which is specifically as follows:

the communication interface 602 is specifically configured to determine, at the first monitoring point, a link model for transmission of the optical signal to be detected according to a network node through which the optical signal to be detected passes acquired by a network side and the model of the at least one network node stored in the memory 603.

That is, when the parameters of the DWDM network system are configured to be dynamically configured, before the transmitting end transmits optical signals with different wavelengths, different optical labels need to be added to the optical signals with different wavelengths respectively in a coding manner, for an optical signal with a wavelength, the network side decodes the optical label when passing through each network node, and re-encodes the optical label to generate a new optical label, therefore, the network side generates information of each network node through which the optical signal with one wavelength is transmitted from the transmitting end according to the decoding and recoding information of the optical signal with one wavelength at each network node, and feeds back information of each network node through which an optical signal of one wavelength is transmitted from the transmitting end to the communication interface 602, that is, information of each network node through which the optical signal to be detected is transmitted from the transmitting end in the unidirectional transmission is fed back to the communication interface 602. At this time, the communication interface 602 determines, at the first monitoring point, the number of each network node and each network node through which the optical signal to be detected that is transmitted in the unidirectional direction passes according to the information of each network node through which the received optical signal to be detected that is transmitted in the unidirectional direction passes, so as to obtain, in the memory 603, a model of each network node through which the optical signal to be detected that is transmitted in the unidirectional direction passes according to the number of each network node and each network node, and further determine a link model of the optical signal to be detected that is transmitted in the unidirectional direction according to the information of each network node and the obtained model of each network node.

It should be noted that, when the parameters of the DWDM network system are configured to be dynamically configured, the communication interface 602 may also obtain a link model of the optical signal transmission to be detected in unidirectional transmission according to other methods, which is not limited in the present invention.

Or, the communication interface 602 is specifically configured to obtain, at the first monitoring point, the link model of the optical signal transmission to be detected from the memory 603.

That is to say, when the parameters of the DWDM network system are configured in a fixed configuration, the network node through which the optical signal to be detected that is transmitted in a single direction passes before the first monitoring point is fixed, so that the link model through which the optical signal to be detected that is transmitted in a single direction passes before the first monitoring point may be stored in the memory 603 in advance in the communication interface 602, so that after the modulation format of the optical signal to be detected that is transmitted in a single direction is obtained, the link model of the optical signal to be detected that is transmitted in a single direction is directly obtained from the memory 603.

For example, assuming that there are 3 network nodes through which the optical signal to be detected in unidirectional transmission passes before the first monitoring point, the network nodes are respectively a first ROADM, a second ROADM and an optical signal amplifier, and the order of the network nodes through which the optical signal to be detected in unidirectional transmission passes before the first monitoring point is the first ROADM, the optical signal amplifier and the second ROADM, the memory 603 stores in advance the link models in which the optical signal to be detected in unidirectional transmission passes through the first ROADM, the optical signal amplifier and the second ROADM in sequence before the first monitoring point, so that after the modulation format of the optical signal to be detected in unidirectional transmission is obtained, the link models in which the optical signal to be detected in unidirectional transmission passes through the first ROADM, the optical signal amplifier and the second ROADM in sequence before the first monitoring point are directly obtained from the memory 603.

The processor 601 is configured to determine a response characteristic of the transmission link of the optical signal to be detected according to the link model acquired by the communication interface 602.

Specifically, when the communication interface 602 acquires the link model of the optical signal to be detected in unidirectional transmission, the processor 601 determines, according to the link model of the optical signal to be detected in unidirectional transmission, a change of a signal spectrum of the optical signal to be detected in unidirectional transmission when the optical signal to be detected passes through each network node, so as to determine a response characteristic of a transmission link of the optical signal to be detected in unidirectional transmission according to a signal spectrum change of the optical signal to be detected passing through each network node.

In a network system having a single optical fiber with bidirectional transmission signals, the communication interface 602 is further configured to obtain, at the first monitoring point, a link model of the optical signal transmission to be detected for the uplink transmission.

Specifically, the method for the communication interface 602 to obtain the link model of the optical signal transmission to be detected for uplink transmission is similar to the method for the communication interface 602 to obtain the link model of the optical signal transmission to be detected for unidirectional transmission in the DWDM network system, and details of the method are not repeated herein.

The communication interface 602 is further configured to obtain, at the first monitoring point, a link model of the optical signal transmission to be detected of the downlink transmission.

Specifically, the method for the communication interface 602 to obtain the link model of the optical signal transmission to be detected in downlink transmission is similar to the method for the communication interface 602 to obtain the link model of the optical signal transmission to be detected in unidirectional transmission in the DWDM network system, and details of the method are not repeated herein.

The processor 601 is further configured to determine, according to the link model obtained by the communication interface 602, a response characteristic of a transmission link of the optical signal to be detected for uplink transmission.

Specifically, when the communication interface 602 acquires the link model of the optical signal to be detected transmitted by the uplink, the processor 601 determines, according to the link model of the optical signal to be detected transmitted by the uplink, a change of a signal spectrum of the optical signal to be detected transmitted by the uplink when the optical signal to be detected transmitted by the uplink passes through each network node, so as to determine a response characteristic of a transmission link of the optical signal to be detected transmitted by the uplink according to a signal spectrum change of the optical signal to be detected transmitted by the uplink passing through each network node.

The processor 601 is further configured to determine, according to the link model obtained by the communication interface 602, a response characteristic of a transmission link of the optical signal to be detected for downlink transmission.

Specifically, when the communication interface 602 acquires a link model of the optical signal to be detected transmitted in the downlink, the processor 601 determines, according to the link model of the optical signal to be detected transmitted in the downlink, a change of a signal spectrum of the optical signal to be detected transmitted in the downlink when the optical signal to be detected transmitted in the downlink passes through each network node, so as to determine a response characteristic of a transmission link of the optical signal to be detected transmitted in the downlink according to a signal spectrum change of the optical signal to be detected transmitted in the downlink passing through each network node.

The communication interface 602 is further configured to obtain a first spectrum.

Specifically, in the DWDM network system, if only one modulation format of the optical signal to be detected is transmitted from the transmitting end, the communication interface 602 directly acquires the first spectrum.

If the modulation format of the optical signal to be detected transmitted by the transmitting end is at least one, the following methods may be used for the communication interface 602 to obtain the first spectrum.

The first method, the communication interface 602, is specifically configured to obtain a modulation format of the optical signal to be detected, and determine the first spectrum according to the modulation format.

That is to say, the communication interface 602 collects the optical signal to be detected in unidirectional transmission at the first monitoring point, and uses the collected optical signal to be detected in unidirectional transmission as its own input signal, the neural network in the communication interface 602 extracts characteristic parameters in the input signal, for example, extracts time domain characteristics of the signal, the time domain characteristics of which include the instantaneous amplitude, instantaneous phase or instantaneous frequency histogram or other statistical parameters of the signal, then forms an input vector according to the extracted characteristic parameter samples, and uses the input vector as the input of the neural network, and trains the network according to a certain neural network function, when the training step number, the training error, the training time or the training gradient value reach a preset threshold value, the training is automatically terminated, and returns to the trained neural network, and matches the trained neural network, the output of the trained neural network is compared with a pre-stored sample, a sample most similar to the output of the trained neural network is found out by adopting a minimum mean square error criterion, and the sample is used as a modulation format of the optical signal to be detected which is acquired by the communication interface 602 and is transmitted in a unidirectional manner, so that the signal spectrum of the optical signal to be detected which is transmitted in the unidirectional manner and does not pass through any network node is determined, namely the first spectrum.

The second method, the communication interface 602, is specifically configured to determine whether the optical signal to be detected carries a pilot signal, and determine the first spectrum according to the pilot signal when it is determined that the optical signal to be detected carries the pilot signal.

That is to say, the communication interface 602 determines, at the first monitoring point, whether the optical signal to be detected that is unidirectionally transmitted carries a pilot signal, and when it is determined that the optical signal to be detected that is unidirectionally transmitted carries a pilot signal, determines a modulation format of the optical signal to be detected that is unidirectionally transmitted according to a frequency of the pilot signal, so as to determine that a signal spectrum of the optical signal to be detected that is unidirectionally transmitted does not pass through any network node, that is, the first spectrum.

It should be noted that the transmitting end may transmit optical signals with different modulation formats, and before transmitting the optical signals, pilot signals with different frequencies are carried in the optical signals with different modulation formats, so that the communication interface 602 may determine the modulation format of the optical signal to be detected that is transmitted in a unidirectional manner according to the frequency of the carried pilot signal.

It should be noted that the communication interface 602 may also obtain the modulation format of the optical signal to be detected in unidirectional transmission according to other methods, which is not limited in the present invention.

It should be noted that, in a network system having bidirectional transmission signals in a single optical fiber, the method for the communication interface 602 to obtain the first spectrum is similar to the method for the communication interface 602 to obtain the first spectrum in a DWDM network system, and the details of the present invention are not repeated herein.

The processor 601 is further configured to determine a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected and the first spectrum acquired by the communication interface 602.

Specifically, in the DWDM network system, the processor 601 is specifically configured to determine the reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected that is unidirectionally transmitted and the first spectrum acquired by the communication interface 602.

That is to say, when the response characteristic of the transmission link of the optical signal to be detected that is unidirectionally transmitted is acquired and the communication interface 602 acquires the first spectrum, the processor 601 multiplies the waveform generated by the response characteristic of the transmission link of the optical signal to be detected that is unidirectionally transmitted by the waveform of the first spectrum acquired by the communication interface 602, so as to obtain a new waveform, that is, the determination reference spectrum.

In a network system having a single optical fiber for bidirectional signal transmission, the processor 601 is further configured to determine a reference spectrum according to a response characteristic of a transmission link of the optical signal to be detected transmitted in the uplink and the first spectrum acquired by the communication interface 602.

That is to say, when determining the response characteristic of the transmission link of the optical signal to be detected transmitted in the uplink and the first spectrum acquired by the communication interface 602, the processor 601 multiplies the waveform generated by the response characteristic of the transmission link of the optical signal to be detected transmitted in the uplink by the waveform of the first spectrum acquired by the communication interface 602, so as to obtain a new waveform, that is, a determination reference spectrum.

The processor 601 is further configured to determine a reference spectrum according to a response characteristic of a transmission link of the optical signal to be detected transmitted in the downlink and the first spectrum acquired by the communication interface 602.

That is to say, when determining the response characteristic of the transmission link of the optical signal to be detected transmitted in the downlink and the first spectrum acquired by the communication interface 602, the processor 601 multiplies the waveform generated by the response characteristic of the transmission link of the optical signal to be detected transmitted in the downlink by the waveform of the first spectrum acquired by the communication interface 602, so as to obtain a new waveform, that is, a determination reference spectrum.

The processor 601 is further configured to determine an optical signal-to-noise ratio of the optical signal to be detected at the first monitoring point according to the reference spectrum and the optical power spectrum of the optical signal to be detected, which is acquired by the communication interface module 602.

Specifically, in the DWDM network system, the processor 601 determines the optical signal-to-noise ratio of the optical signal to be detected in unidirectional transmission at the first monitoring point according to the determined reference spectrum and the optical power spectrum of the optical signal to be detected in unidirectional transmission acquired by the communication interface 602, and the specific determination method includes the following steps:

step one, the processor 601 selects two bands with different center wavelengths and the same bandwidth from the optical power spectrum of the optical signal to be detected of the unidirectional transmission acquired by the communication interface 602, that is, selects two bands with different center frequencies and the same bandwidth, and respectively records the two bands as a first band and a second band, and calculates a power value P (BW) of the first band₁) And power value P (BW) of the second band₂) (ii) a Selecting a third wave band with the same center frequency and bandwidth as the first wave band and a fourth wave band with the same center frequency and bandwidth as the second wave band from the determined reference spectrum, and calculating the power value R (BW) of the third wave band₁) And a power value R (BW) of a fourth band₂)。

Step two, the processor 601 calculates the power value P (BW) of the first band of the optical signal to be detected transmitted unidirectionally according to the calculated value₁) And a secondPower value P (BW) of band₂) Is compared with the power value R (BW) of the third band of the reference spectrum₁) And a power value R (BW) of a fourth band₂) The difference value is divided, and the ratio of the total power of the optical signal to be detected which is transmitted in a single direction to the total power of the reference spectrum is calculated, namely:

the processor 601 is according to a formulaAnd calculating the ratio of the total power of the optical signal to be detected in unidirectional transmission to the total power of the reference spectrum.

Step three, the processor 601 multiplies the ratio of the total power of the optical signal to be detected in unidirectional transmission to the total power of the reference spectrum, and determines the actual signal total power of the optical signal to be detected in unidirectional transmission; and determining the actual noise total power of the optical signal to be detected in the unidirectional transmission according to the total power of the reference spectrum and the ratio of the total power of the optical signal to be detected in the unidirectional transmission to the total power of the reference spectrum. Namely:

the processor 601 is according to formula S_eAnd KR is used for acquiring the signal power value of the optical signal to be detected which is transmitted in the unidirectional mode.

It should be noted that the total power P of the optical signal to be detected in the unidirectional transmission is obtained by integrating the optical power spectrum of the acquired optical signal to be detected in the unidirectional transmission by the processor 601; the total power R of the reference spectrum is obtained by the processor 601 integrating the acquired reference spectrum.

And step four, the processor 601 determines the optical signal to noise ratio of the optical signal to be detected in the unidirectional transmission according to the ratio of the total power of the actual signal of the optical signal to be detected in the unidirectional transmission to the total power of the actual noise of the optical signal to be detected in the unidirectional transmission. Namely:

the processor 601 is according to a formulaAnd calculating the optical signal-to-noise ratio of the optical signal to be detected which is transmitted in the one-way mode on the first monitoring point.

It should be noted that, the processor 601 may also be another method for determining the optical signal-to-noise ratio of the optical signal to be detected in the unidirectional transmission according to the optical power spectrum and the reference spectrum of the optical signal to be detected in the unidirectional transmission, which is not limited in the present invention.

It should be noted that, in a network system having a bidirectional transmission signal in a single optical fiber, the method for determining the optical signal-to-noise ratio of the optical signal to be detected transmitted in the uplink and the method for determining the optical signal-to-noise ratio of the optical signal to be detected transmitted in the downlink by the processor 601 are similar to the method for determining the optical signal-to-noise ratio of the optical signal to be detected transmitted in the unidirectional transmission in the DWDM network system by the processor 601, and the description of the present invention is omitted here.

The embodiment of the invention provides a device for detecting an optical signal to noise ratio, wherein after the optical signal to be detected is obtained, the detection device obtains an optical power spectrum of the optical signal to be detected at a first monitoring point, and obtains a link model and a first spectrum for transmitting the optical signal to be detected at the first monitoring point, so that the response characteristic of a transmission link of the optical signal to be detected is determined according to the obtained link model, a reference spectrum is determined according to the response characteristic of the transmission link of the optical signal to be detected and the first spectrum, and finally the optical signal to noise ratio of the optical signal to be detected at the first monitoring point is determined according to the optical power spectrum of the optical signal to be detected and the reference spectrum. In this way, the reference spectrum adopted by the detection device when determining the osnr of the optical signal to be detected is determined according to the link model of the optical signal to be detected and the first spectrum, thereby reducing the osnr error of the optical signal to be detected.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other manners. 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 invention may be integrated into one processing unit, or each unit may be physically included alone, or two or more units may be integrated into one unit. The integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit.

The integrated unit implemented in the form of a software functional unit may be stored in a computer readable storage medium. The software functional unit 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 some steps of the methods according to the embodiments of the present invention. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A detection device, comprising: the device comprises a signal acquisition unit, a coherent receiving unit, a reference spectrum acquisition unit and a spectrum analysis unit; wherein,

the signal acquisition unit is used for acquiring an optical signal to be detected;

the coherent receiving unit is used for detecting the optical signal to be detected on a first monitoring point and acquiring an optical power spectrum of the optical signal to be detected;

the reference spectrum acquisition unit is used for acquiring a link model of the optical signal transmission to be detected at the first monitoring point and determining the response characteristic of the transmission link of the optical signal to be detected according to the link model;

the reference spectrum acquisition unit is also used for acquiring a first spectrum; the first spectrum is a signal spectrum which is transmitted by a transmitting terminal and does not pass through any network node;

the reference spectrum acquisition unit is further configured to determine a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected and the first spectrum;

and the spectrum analysis unit is used for determining the optical signal to noise ratio of the optical signal to be detected on the first monitoring point according to the optical power spectrum of the optical signal to be detected and the reference spectrum.

2. The apparatus of claim 1, wherein the reference spectrum obtaining unit is further configured to obtain the first spectrum comprising:

the reference spectrum acquisition unit is specifically configured to acquire a modulation format of the optical signal to be detected, and determine the first spectrum according to the modulation format; or,

the reference spectrum obtaining unit is specifically configured to determine whether the optical signal to be detected carries a pilot signal, and determine the first spectrum according to the pilot signal when it is determined that the optical signal to be detected carries the pilot signal.

3. The apparatus of claim 1 or 2, further comprising: a storage unit;

the storage unit is configured to pre-store a link model for optical signal transmission to be detected, or pre-store a model of at least one network node through which the optical signal to be detected passes during transmission;

the reference spectrum obtaining unit, configured to obtain, at the first monitoring point, the link model of the optical signal transmission to be detected, includes:

the reference spectrum acquisition unit is specifically configured to acquire, from the storage unit, a link model of optical signal transmission to be detected at the first monitoring point; or,

the reference spectrum obtaining unit is specifically configured to determine, at the first monitoring point, a link model for transmission of the optical signal to be detected according to a network node through which the optical signal to be detected passes obtained by a network side and the model of the at least one network node stored in the storage unit.

4. The apparatus of claim 1, wherein the coherent receiving unit comprises: the system comprises a polarization control module, a local oscillator laser module, a first polarization beam splitting module, a second polarization beam splitting module, a first optical frequency mixing module, a second optical frequency mixing module, a photoelectric detection module, an analog-to-digital conversion module and a digital signal processing module;

the coherent receiving unit, configured to obtain an optical power spectrum of the optical signal to be detected, includes:

the local oscillator laser module is used for transmitting local oscillator optical signals at a first frequency interval;

the first polarization beam splitting module is configured to split the optical signal to be detected into a first optical signal and a second optical signal that are orthogonal to each other, and input the first optical signal and the second optical signal to the first optical mixing module and the second optical mixing module, respectively;

the second polarization beam splitting module is configured to split the local oscillator optical signal into a first local oscillator optical signal and a second local oscillator optical signal that are orthogonal to each other, and input the first local oscillator optical signal and the second local oscillator optical signal to the first optical frequency mixing module and the second optical frequency mixing module, respectively;

the polarization control module is configured to control the first optical signal and the first local oscillator optical signal so that directions of the first optical signal and the first local oscillator optical signal are the same, and control the second optical signal and the second local oscillator optical signal so that directions of the second optical signal and the second local oscillator optical signal are the same;

the first optical frequency mixing module is configured to perform frequency mixing on the first optical signal and the first local oscillator optical signal to obtain a first frequency mixing signal, and input the first frequency mixing signal to the photodetection module; wherein the first mixing signal comprises at least two mutually orthogonal optical signals;

the second optical frequency mixing module is configured to perform frequency mixing on the second optical signal and the second local oscillator optical signal to obtain a second frequency mixing signal, and input the second frequency mixing signal to the photoelectric detection module; wherein the second mixing signal comprises at least two mutually orthogonal optical signals;

the photoelectric detection module is configured to detect the first mixing signal and the second mixing signal, obtain an analog optical power signal of the first mixing signal and the second mixing signal, and input the analog optical power signal to the analog-to-digital conversion module;

the analog-to-digital conversion module is used for converting the analog optical power signal into a digital optical power signal and inputting the digital optical power signal to the digital signal processing module;

the digital signal processing module is used for performing first processing on the digital optical power signal to obtain an optical power spectrum of the optical signal to be detected; the first processing comprises Fast Fourier Transform (FFT), frequency spectrum splicing, power correction and coefficient compensation.

5. The apparatus of claim 1, wherein the signal obtaining unit for obtaining the optical signal to be detected comprises:

the signal acquisition unit is specifically used for acquiring the optical signal to be detected in unidirectional transmission; or,

the signal acquiring unit is specifically configured to acquire the optical signal to be detected transmitted by an uplink and the optical signal to be detected transmitted by a downlink.

6. The apparatus of claim 5, wherein the reference spectrum obtaining unit comprises: an uplink reference spectrum acquisition module and a downlink reference spectrum acquisition module;

the uplink reference spectrum acquisition module is configured to acquire a link model of optical signal transmission to be detected transmitted in the uplink transmission at the first monitoring point, and determine a response characteristic of a transmission link of the optical signal to be detected transmitted in the uplink transmission according to the link model;

the uplink reference spectrum acquisition module is further configured to determine a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected transmitted by the uplink and the first spectrum;

the downlink reference spectrum acquisition module is configured to acquire a link model of optical signal transmission to be detected transmitted in the downlink transmission at the first monitoring point, and determine a response characteristic of a transmission link of the optical signal to be detected transmitted in the downlink transmission according to the link model;

the downlink reference spectrum acquisition module is further configured to determine a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected transmitted in the downlink and the first spectrum.

7. A method for detecting an optical signal-to-noise ratio, comprising:

the detection device acquires an optical signal to be detected;

the detection device acquires an optical power spectrum of the optical signal to be detected at a first monitoring point;

the detection device acquires a link model of the optical signal transmission to be detected at the first monitoring point, and determines the response characteristic of the transmission link of the optical signal to be detected according to the link model;

the detection device acquires a first spectrum; wherein the first spectrum is a signal spectrum emitted by an emitting end and not passing through any device;

the detection device determines a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected and the first spectrum;

and the detection device determines the optical signal-to-noise ratio of the optical signal to be detected on the first monitoring point according to the optical power spectrum of the optical signal to be detected and the reference spectrum.

8. The method of claim 7, wherein the detecting means acquiring a first spectrum comprises:

the detection device acquires a modulation format of the optical signal to be detected, and determines the first spectrum according to the modulation format; or,

the detection device determines whether the optical signal to be detected carries a pilot signal, and determines the first spectrum according to the pilot signal when determining that the optical signal to be detected carries the pilot signal.

9. The method according to claim 7 or 8, wherein the detecting device obtaining the link model of the optical signal transmission to be detected at the first monitoring point comprises:

the detection device acquires a pre-stored link model for optical signal transmission to be detected from the first monitoring point; or,

and the detection device determines a link model for transmission of the optical signal to be detected at the first monitoring point according to the network node through which the optical signal to be detected passes and a pre-stored model of at least one network node acquired by a network side.

10. The method of claim 7, wherein the detecting device acquiring the optical power spectrum of the optical signal to be detected at the first monitoring point comprises:

the detection device transmits local oscillator optical signals at a first frequency interval, and divides the transmitted local oscillator optical signals into a first local oscillator optical signal and a second local oscillator optical signal which are orthogonal to each other;

the detection device divides the acquired optical signal to be detected into a first optical signal and a second optical signal which are orthogonal to each other, controls the directions of the first optical signal and the first local oscillator optical signal so as to enable the direction of the first optical signal to be consistent with the direction of the first local oscillator optical signal, and controls the directions of the second optical signal and the second local oscillator optical signal so as to enable the direction of the second optical signal to be the same as the direction of the second local oscillator optical signal;

the detection device mixes the first optical signal with the first local oscillator optical signal to obtain a first mixed frequency signal, and mixes the second optical signal with the second local oscillator optical signal to obtain a second mixed frequency signal; wherein the first mixing signal comprises at least two mutually orthogonal optical signals; the second mixing signal comprises at least two mutually orthogonal optical signals;

the detection device detects the first mixing signal and the second mixing signal, obtains analog optical power signals of the first mixing signal and the second mixing signal, and converts the analog optical power signals into digital optical power signals;

the detection device carries out first processing on the digital optical power signal to obtain an optical power spectrum of the optical signal to be detected; the first processing comprises Fast Fourier Transform (FFT), frequency spectrum splicing, power correction and coefficient compensation.

11. The method of claim 7, wherein the detecting device acquiring the optical signal to be detected comprises:

the detection device acquires the optical signal to be detected in one-way transmission; or,

the detection device acquires the optical signal to be detected transmitted by an uplink and the optical signal to be detected transmitted by a downlink.

12. The method according to claim 11, wherein the detecting device obtains a link model of the optical signal transmission to be detected at the first monitoring point, and determining the response characteristic of the transmission link of the optical signal to be detected according to the link model comprises:

the detection device acquires a link model of the optical signal transmission to be detected transmitted by the uplink at the first monitoring point, and determines the response characteristic of the transmission link of the optical signal to be detected transmitted by the uplink according to the link model; or,

the detection device acquires a link model of optical signal transmission to be detected transmitted in the downlink from the first monitoring point, and determines the response characteristic of the transmission link of the optical signal to be detected transmitted in the downlink according to the link model;

the determining, by the detection device, a reference spectrum according to the response characteristic of the transmission link of the optical signal to be detected and the first spectrum includes:

the detection device determines the optical signal-to-noise ratio of the optical signal to be detected transmitted by the uplink on the first monitoring point according to the optical power spectrum of the optical signal to be detected transmitted by the uplink and the reference spectrum; or,

and the detection device determines the optical signal-to-noise ratio of the optical signal to be detected transmitted by the downlink on the first monitoring point according to the optical power spectrum of the optical signal to be detected transmitted by the downlink and the reference spectrum.

13. A detection device, comprising:

the communication interface is used for acquiring an optical signal to be detected;

the communication interface is further configured to acquire an optical power spectrum of the optical signal to be detected at a first monitoring point;

the communication interface is further configured to acquire a link model of optical signal transmission to be detected at the first monitoring point;

the processor is used for determining the response characteristic of the transmission link of the optical signal to be detected according to the link model acquired by the communication interface;

the communication interface is further used for acquiring a first spectrum; the first spectrum is a signal spectrum which is transmitted by a transmitting terminal and does not pass through any network node;

the processor is further configured to determine a reference spectrum according to the first spectrum acquired by the communication interface and response characteristics of a transmission link of the optical signal to be detected;

the processor is further configured to determine an optical signal-to-noise ratio of the optical signal to be detected at the first monitoring point according to the reference spectrum and the optical power spectrum of the optical signal to be detected, which is acquired by the communication interface.