Optical Signal-to-Noise Ratio Detection Method, Apparatus and Computer Storage Medium

Abstract

The present invention discloses an optical signal-to-noise ratio (OSNR) detection method, device, and computer storage medium. The OSNR detection method includes adjusting a detection light source to a spontaneous radiation state; adjusting the signal width of the detection light source to a first width based on the spectrum bandwidth of the channel to be measured, and obtaining the total channel power at the optical performance monitoring point of the receiving station; adjusting the signal width of the detection light source to a second width, and obtaining the noise power at the optical performance monitoring point of the receiving station, wherein the second width is smaller than the first width and the center frequencies of the corresponding signals of the two are staggered; and determining the OSNR of the channel to be measured based on the total channel power and noise power. By providing detection light to the channel to be measured through the detection light source, while simultaneously changing the waveform of the detection light source and using the total channel power and noise power monitored by the optical performance monitoring point of the receiving station, the OSNR of the channel to be measured is calculated, thereby achieving optical performance monitoring of idle service paths and greatly improving network maintenance and management capabilities.

Description

Technical Field

[0001] The present invention relates to the technical field of optical performance detection, and in particular to an optical signal-to-noise ratio detection method, device and computer storage medium. Background Art

[0002] Optical Transport Network (OTN) is a new optical transport technology that enables the transmission, switching, and multiplexing of signals at various granularities. OTNs place significant demands on service survivability, requiring a significant amount of idle optical path resources to provide recovery paths for failed services.

[0003] Currently, mainstream optical path performance testing technologies are based on measuring the performance parameters of service optical signals along the optical path, such as optical power and optical signal-to-noise ratio (OSNR), to evaluate the performance of the test optical path. However, idle channels in optical transport networks lack service optical signals, and components such as optical switches and wavelength selective switches (WSSs) passing through them are also turned off. In this situation, existing technologies are unable to monitor the optical performance of these idle channels. Summary of the Invention

[0004] The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

[0005] The embodiments of the present invention provide an optical signal-to-noise ratio detection method, device, and computer storage medium, which implement optical signal-to-noise ratio detection of an idle channel by adjusting the signal width of a detection light source.

[0006] In a first aspect, an embodiment of the present invention provides an optical signal-to-noise ratio detection method, which is applied to an optical signal-to-noise ratio detection system. The optical signal-to-noise ratio detection system includes a detection light source disposed at a transmitting site, wherein an output end of the detection light source is connected to a line-side port of the transmitting site. The optical signal-to-noise ratio detection method includes:

[0007] Adjusting the detection light source to be in a spontaneous radiation state;

[0008] Adjusting the signal width of the detection light source to a first width based on the spectrum bandwidth of the channel to be measured, and obtaining the total channel power at the optical performance monitoring point of the receiving site, wherein the channel to be measured is an idle channel from the line-side port of the transmitting site to the line-side port of the receiving site, and the first width is not greater than the spectrum bandwidth of the channel to be measured;

[0009] Adjusting the signal width of the detection light source to a second width, and obtaining the noise power at the optical performance monitoring point of the receiving end site, wherein the second width is smaller than the first width and a center frequency of a signal corresponding to the second width is staggered from a center frequency of a signal corresponding to the first width;

[0010] The optical signal-to-noise ratio of the channel to be measured is determined according to the total channel power and the noise power.

[0011] In a second aspect, an embodiment of the present invention provides an optical signal-to-noise ratio detection method, which is applied to an optical signal-to-noise ratio detection system. The optical signal-to-noise ratio detection system includes a detection light source provided at a remote site, and an output end of the detection light source is connected to a line-side port of the remote site. The optical signal-to-noise ratio detection method includes:

[0012] Adjusting the detection light source to be in a spontaneous radiation state;

[0013] Adjusting the signal width of the detection light source to a first width according to the spectrum bandwidth of the channel to be measured, obtaining the total power of the first channel at the optical performance monitoring point of the transmitting site and the total power of the second channel at the optical performance monitoring point of the receiving site, wherein the channel to be measured is an idle channel from the line-side port of the transmitting site to the line-side port of the receiving site, and the first width is no greater than the spectrum bandwidth of the channel to be measured;

[0014] Adjusting the signal width of the detection light source to a second width, obtaining a first noise power at an optical performance monitoring point of the transmitting site and a second noise power at an optical performance monitoring point of the receiving site, wherein the second width is smaller than the first width and a center frequency of a signal corresponding to the second width is staggered from a center frequency of a signal corresponding to the first width;

[0015] The optical signal-to-noise ratio of the channel to be measured is determined according to the first channel total power, the second channel total power, the first noise power, and the second noise power.

[0016] In a third aspect, an embodiment of the present invention provides an optical signal-to-noise ratio detection system, comprising at least one processor and a memory for communicating with the at least one processor; the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the optical signal-to-noise ratio detection method as described in the first aspect or the optical signal-to-noise ratio detection method as described in the second aspect.

[0017] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the optical signal-to-noise ratio detection method as described in the first aspect or the optical signal-to-noise ratio detection method as described in the second aspect.

[0018] The optical signal-to-noise ratio detection method provided by the embodiments of the present invention has at least the following beneficial effects: the optical signal-to-noise ratio detection method of the embodiments of the present invention is applied to an idle service path. A detection light source is used to provide detection light to the channel under test. The waveform of the detection light source is simultaneously changed. The total channel power and noise power monitored by an optical performance monitoring point at a receiving site are used to calculate the optical signal-to-noise ratio of the channel under test. This enables optical performance monitoring of the idle service path, significantly improving network maintenance and management capabilities. Compared to existing optical performance monitoring solutions, the signal width of the detection light source is adjusted based on the spectral bandwidth of the channel under test. This can better adapt to the environment of the channel under test when it is transmitting service, thereby obtaining a more accurate optical signal-to-noise ratio result.

[0019] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purposes and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the technical solution of the present invention and constitute a part of the specification. Together with the examples of the present invention, they are used to explain the technical solution of the present invention and do not constitute a limitation to the technical solution of the present invention.

[0021] Figure 1 This is a flow chart of the overall method of optical signal-to-noise ratio detection method provided by one embodiment of the present invention;

[0022] Figure 2 is a schematic diagram of channel power at a first width provided by an embodiment of the present invention;

[0023] Figure 3 is a schematic diagram of channel power under a second width provided by an embodiment of the present invention;

[0024] Figure 4 This is a flow chart of adjusting the working state of a detection light source provided by an embodiment of the present invention;

[0025] Figure 5 This is a flow chart of calculating the optical signal-to-noise ratio of a channel to be measured under a direct connection to an idle port provided by an embodiment of the present invention;

[0026] Figure 6This is a flow chart of calculating the optical signal-to-noise ratio of a channel to be measured under a non-directly connected idle port provided by an embodiment of the present invention;

[0027] Figure 7 This is a flow chart of the overall method of optical signal-to-noise ratio detection method provided by one embodiment of the present invention;

[0028] Figure 8 This is a flow chart of calculating the optical signal-to-noise ratio of a channel to be measured in a remote site situation provided by one embodiment of the present invention;

[0029] Figure 9 This is a schematic diagram of the network structure provided by Example 1 of the present invention;

[0030] Figure 10 This is a schematic diagram of the network structure provided by Example 2 of the present invention;

[0031] Figure 11 This is a schematic diagram of the network structure provided in Example 3 of the present invention. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0033] Optical Transport Network (OTN) inherits the advantages of Synchronous Digital Hierarchy (SDH) and Wavelength Division Multiplexing (DWM) networks, combining their large capacity and robust control mechanisms. OTN enables the transmission, switching, and multiplexing of signals at various granularities. Furthermore, OTN supports a wide range of upper-layer services and protocols, making it a crucial networking technology for optical transport networks.

[0034] OTN increases the transmission capacity of a single optical fiber by combining and transmitting different wavelengths simultaneously along a single fiber. The combined signal of different wavelengths is amplified by optical amplifiers at the site as it passes through the site, increasing the transmission distance. However, the amplifiers also amplify noise signals during the signal amplification process, resulting in a significant increase in noise after the signal passes through multiple amplifiers. To monitor and control the signal quality at each site, optical performance monitoring has been introduced into optical communication networks, with OSNR being a crucial indicator in optical performance testing.

[0035] OSNR is the ratio of optical signal power to noise power within an effective bandwidth of 0.1nm. By selecting a specific wavelength channel at a site for measurement, the optical signal power and noise power output by the optical amplifier device at that site can be obtained, thereby evaluating the channel quality of that wavelength channel between sites. Therefore, to obtain the optical signal power and noise power, it is necessary to monitor the service optical signals on the service path. Monitoring idle channels without service optical signals is not possible. To ensure service survivability, OTN reserves a large number of idle optical path resources to provide recovery path resources for failed services. However, since the optical performance indicators of idle channels cannot be predicted in advance, when a service failure occurs and is switched to these idle channels, the service cannot be successfully restored, resulting in long service interruptions and seriously affecting the network service quality.

[0036] Based on this, an embodiment of the present invention provides an optical signal-to-noise ratio detection method, which provides a detection means for detecting the OSNR of an idle channel to be tested. By changing the waveform of the detection light source and utilizing optical performance monitoring technology, the signal power and noise power of the channel to be tested are respectively detected at the receiving site, thereby calculating the OSNR of the channel to be tested and realizing optical performance monitoring of the idle channel.

[0037] Reference Figure 1 An embodiment of the present invention provides an optical signal-to-noise ratio detection method, which is applied to an optical signal-to-noise ratio detection system. The optical signal-to-noise ratio detection system includes a detection light source disposed at a transmitting site, wherein an output end of the detection light source is connected to a line-side port of the transmitting site. The optical signal-to-noise ratio detection method includes but is not limited to the following steps S100, S200, S300, and S400.

[0038] Step S100: adjusting the detection light source to be in a spontaneous radiation state.

[0039] To measure the OSNR of an idle channel, this embodiment of the present invention connects an additional detection light source to the channel under test, providing the optical signal for measurement. Because the detection light source does not actually carry traffic, a noise signal is generated using spontaneous emission, which serves as the initial optical signal for OSNR measurement.

[0040] It is understandable that the idle channel corresponds to an idle port in the current site in terms of hardware. The idle port can be the upper port or loopback port of an optical switch (such as an optical filter), the input port or loopback port of a combiner such as a coupling device, the upper port of an arrayed waveguide grating (AWG) device, etc. In addition, an idle channel corresponds to a wavelength channel on the optical path that does not carry any service, which means that the wavelength channel does not carry any service only at the monitoring moment. It can also mean that the wavelength channel is not scheduled to carry any service and is completely idle. The determination of an idle channel can be made by a tester based on the actual service activation situation, or it can be automatically determined by detecting whether there is any service message on the wavelength channel, which is not limited here.

[0041] The detection light source can be composed of different hardware methods. For example, the detection light source directly uses a tunable laser light source to generate a laser with a central wavelength corresponding to the channel to be measured. However, the tunable laser light source can only generate a laser with a central wavelength at a time, which has certain limitations. For another example, the detection light source is composed of a spontaneous radiation source and an optical filter. The output end of the spontaneous radiation source is connected to the input end of the optical filter, and the output end of the optical filter is connected to the idle port. Among them, the spontaneous radiation source can use an erbium doped fiber application amplifier (EDFA). At this time, the input end of the EDFA is not connected to the input source, and the EDFA is placed in the spontaneous radiation (Amplified Spontaneous Emission, ASE) state. A noise source covering multiple channels can be obtained, and the optical filter can be various wave combiner and splitter devices with filtering functions such as AWG and WSS, which are used to select wavelength channels for the EDFA.

[0042] Step S200: Adjusting the signal width of the detection light source to a first width based on the spectrum bandwidth of the channel to be measured, and obtaining the total channel power at the optical performance monitoring point of the receiving site. The channel to be measured is an idle channel from the line-side port of the transmitting site to the line-side port of the receiving site, and the first width is no greater than the spectrum bandwidth of the channel to be measured.

[0043] Step S300: Adjust the signal width of the detection light source to a second width, obtain the noise power at the optical performance monitoring point of the receiving end site, the second width is smaller than the first width and the center frequency of the signal corresponding to the second width is staggered with the center frequency of the signal corresponding to the first width.

[0044] In this embodiment of the present invention, the two ends of the channel to be measured are defined as the line-side port of the transmitting site and the line-side port of the receiving site, respectively. Service add / drop paths on the equipment side of the transmitting site and service add / drop paths on the equipment side of the receiving site are not included. Therefore, the OSNR of the channel to be measured in this embodiment of the present invention actually refers to the OSNR between the optical performance monitoring points of the two sites.

[0045] Typically, an optical signal at an optical performance monitoring point can only capture the power of the current channel. To obtain the OSNR of the channel under test, embodiments of the present invention employ a method of varying the waveform of the detection light source, measuring the power of the current channel at both ends of the receiving station, thereby calculating the signal optical power of the channel under test. Specifically, in step S200, the signal width of the detection light source is set to a first width based on the spectral width of the channel under test. This ensures that the detection light source fills the spectral width of the channel under test with an optical signal of the corresponding width. This ensures that the total channel power measured at the optical performance monitoring point at the receiving station closely matches the actual service-carrying scenario of the channel under test, and also facilitates subsequent variation of the detection light source's signal width to obtain the noise power. Then, in step S300, the signal width of the detection light source is changed to a second width. Since the second width is smaller than the first width, the operation of step S300 actually narrows the detection light source so that only a certain width of the optical signal exists in the channel to be tested, and the remaining wavelength channels outside the width are shielded by the optical filter. In this way, after the optical signal of the second width passes through the various amplifier devices of the channel to be tested and reaches the receiving end site, the remaining wavelength channels will show a noise floor. Then, the power of these wavelength channels measured at the optical performance monitoring point of the receiving end site is the noise power, which can be referred to as Figure 2 and Figure 3 As shown, they are waveform diagrams under the first width and the second width respectively.

[0046] It is worth noting that the first width can be set to be equal to the spectrum width of the channel to be measured, so that the detection light source can fill the entire channel to be measured, and the total channel power obtained is more accurate. It can also be set to be slightly smaller than the spectrum width of the channel to be measured. In this case, the first width is determined based on an empirical value to facilitate the subsequent measurement of OSNR. The second width can be set according to the network architecture of the channel to be measured. For example, in a 100G optical transmission system, the two adjacent channels used to carry services are 100GHz apart, and the optical channel spectrum width is 50GHz. The optical filter can set the signal width to 12.5GHz, then there is 37.5GHz of idle position in 50GHz for measuring the noise floor, and the width of 12.5GHz can be selected to measure the noise power. It can be understood that in order to measure OSNR by noise power, the center frequency of the signal under the second width is offset relative to the center frequency of the signal under the first width, so that data monitoring is performed on the channel corresponding to the center frequency of the signal under the first width at the optical performance monitoring point.

[0047] It is understood that optical performance monitoring points can be implemented using optical performance monitoring modules (OPMs). With the maturity of reconfigurable optical add-drop multiplexer (ROADM) technology, OPMs are widely used for online channel optical power monitoring, facilitating the measurement of optical performance indicators such as OSNR. OPMs can be implemented in a variety of ways, such as diffraction-based structures consisting of volume gratings and array detectors, or interferometric structures using tunable optical filter (TOF) technology, which are not limited here.

[0048] Step S400: determining the optical signal-to-noise ratio of the channel to be measured according to the total channel power and the noise power.

[0049] After the total channel power and noise power are obtained in the above steps S200 and S300, the signal optical power can be obtained by subtracting the two. According to the calculation formula of the signal optical power, the noise power and the corresponding OSNR, the OSNR of the channel to be measured can be obtained.

[0050] Among them, OSNR = (total channel power - noise power) / noise power corresponding to 0.1nm spectrum width. OCh Indicates the first width, B noise Indicates the second width, B 0.1 Indicates a spectral width of 0.1 nm, P OCh Indicates the total channel power, P noise represents the noise power, then OSNR can be calculated as follows:

[0051]

[0052] Through the above steps, a detection light source is provided for an idle channel under test, and the signal width of the detection light source is varied, so that the total channel power and noise power of the channel under test can be obtained at the optical performance testing point at the receiving site, thereby calculating the OSNR of the channel under test. The spectral width of the channel under test can be selected to a larger value, for example, at a 50 GHz width. This embodiment of the present invention can still provide detection light that fills the spectral width, effectively simulating an environment in which the channel under test is carrying services in a multi-wavelength environment. Therefore, the measured OSNR is more closely aligned with actual service scenarios.

[0053] It's important to note that the OSNR calculated in the above formula doesn't necessarily represent the OSNR value of the channel under test. Depending on the location of the test light source at the receiving site, the resulting OSNR may include the OSNR between the device-side add port and the line-side port. In this case, the OSNR calculated in the above formula is subtracted from the OSNR between the device-side add port and the line-side port to obtain the OSNR of the channel under test. Because the location of the test light source is involved, this part of the OSNR correction is explained in detail below based on different test light source locations.

[0054] Based on the above overall solution, in order to further fit the actual business scenario of the channel to be tested, the power of the spontaneous radiation source can be adjusted. Figure 4 , which can be achieved through the following steps:

[0055] Step S110, placing the spontaneous radiation source in a spontaneous radiation state;

[0056] Step S120: Adjust the spontaneous radiation power of the spontaneous radiation source to be the same as the service access power of the channel to be measured.

[0057] Considering the power that needs to be set for the channel under test when carrying services, that is, the service access power, the power of the spontaneous emission source in the ASE state is adjusted to the same as the service access power. In this way, based on the power characteristics of the optical signal transmitted in the channel under test, the power received by the receiving site at this time is similar to the power received by the channel under test when carrying services. Therefore, the OSNR calculated based on the received power at this time can accurately reflect the actual OSNR in the service carrying scenario.

[0058] It is understandable that the detection light source is set at the originating site to connect to the line side port of the originating site, which is divided into two cases: a direct connection port and an indirect connection port. The following describes these two connection methods in detail.

[0059] (1) The output end of the detection light source is directly connected to the line side port of the transmitting site. The output end of the detection light source can be connected to the line side port of the transmitting site end-to-end through a single optical fiber. In this case, the detection light source does not pass through the device side port of the transmitting site.

[0060] In the above case, the OSNR calculation in step S400 is achieved by the following steps, referring to Figure 5 :

[0061] Step S410, determining the signal optical power of the channel to be measured according to the total channel power and the noise power;

[0062] Step S420 , determining the optical signal-to-noise ratio of the channel to be measured according to the spectrum bandwidth, signal optical power, and noise power of the channel to be measured.

[0063] First, determine the signal optical power of the channel to be measured. Since the total channel power detected at the receiving site is the superposition of the signal optical power and the noise power, the signal optical power can be obtained by simply subtracting the noise power from the total channel power. Then, the OSNR of the channel to be measured can be calculated using the above OSNR calculation formula.

[0064] Because services need to pass through the add / drop ports on the equipment side in the OTN, including the two sections from the equipment side add port at the transmitting site to the line side port at the transmitting site and from the line side port at the receiving site to the equipment side drop port at the receiving site, in order to obtain the OSNR value of the service in the actual transmission path, the OSNR obtained above is corrected:

[0065]

[0066] Among them, OSNR 业务 Indicates the OSNR of the actual transmission path of the service, OSNR 待测 Indicates the OSNR of the channel to be tested, OSNR 上路 Indicates the OSNR from the device-side add port at the originating site to the line-side port at the originating site. 下路 Indicates the OSNR of the dropped channel from the line-side port at the receiving site to the device-side port at the receiving site.

[0067] (2) When the output end of the detection light source is connected to the line-side port of the transmitting site through the add port of the transmitting site, it means that there is no idle port on the line side, but there is an idle add port on the device side. The detection light source can be directly connected to the add port.

[0068] In the above case, the OSNR calculation in step S400 is achieved by the following steps, referring to Figure 6 :

[0069] Step S430, determining the signal optical power of the channel to be measured according to the total channel power and the noise power;

[0070] Step S440, obtaining an added optical signal-to-noise ratio from the device-side added port of the originating site to the line-side port of the originating site;

[0071] Step S450 , determining the optical signal-to-noise ratio of the channel to be measured according to the spectrum bandwidth, the added optical signal-to-noise ratio, the signal optical power, and the noise power of the channel to be measured.

[0072] Similarly, first determine the signal optical power of the channel to be measured. Since the total channel power detected at the receiving site is the sum of the signal optical power and the noise power, the signal optical power can be obtained by simply subtracting the noise power from the total channel power. Then, according to the above OSNR calculation formula, the OSNR between the equipment-side add port at the transmitting site and the line-side port at the receiving site can be obtained. This OSNR includes the OSNR of the channel to be measured and the OSNR between the equipment-side add port at the transmitting site and the line-side port at the transmitting site. Therefore, the OSNR of the channel to be measured is calculated as follows:

[0073]

[0074] Among them, OSNR 待测 Indicates the OSNR of the channel to be tested. OSNR1 indicates the OSNR between the device-side add port at the transmitting site and the line-side port at the receiving site. 上路 Indicates the OSNR from the device-side added port at the originating site to the line-side port at the originating site.

[0075] To obtain the OSNR value of the service in the actual transmission path, the OSNR of the drop channel from the line-side port of the receiving site to the device-side of the receiving site can be added to OSNR1, as shown in the following formula:

[0076]

[0077] Among them, OSNR 业务 Indicates the OSNR of the actual transmission path of the service, OSNR 下路 Indicates the OSNR of the dropped channel from the line-side port at the receiving site to the device-side port at the receiving site.

[0078] It is understandable that the above OSNR 上路 and OSNR 下路 The OSNR values of these segments can be obtained through conventional means during the site deployment or operation and maintenance phase, which will not be described in detail here.

[0079] On the other hand, the path from the add port to the line-side port may pass through multiple components, such as several amplifiers and optical filters. Therefore, the OSNR from the equipment-side add port at the transmitting site to the line-side port at the transmitting site may be composed of multiple OSNR segments. Similarly, the OSNR from the line-side port at the receiving site to the equipment-side drop port at the receiving site may also be composed of multiple OSNR segments. The specific OSNR depends on the actual device connection method at the site.

[0080] According to the above two OSNR measurement scenarios, the detection light sources are all set at the originating site and are directly or indirectly connected to the line-side port of the originating site. However, in some cases, there are no idle ports locally at the originating site, and the channel to be measured needs to be measured through the idle ports of the remote site. Therefore, an embodiment of the present invention also provides an optical signal-to-noise ratio detection method, which is applied to an optical signal-to-noise ratio detection system. The optical signal-to-noise ratio detection system includes a detection light source set at a remote site, and the output end of the detection light source is connected to the line-side port of the remote site. The optical signal-to-noise ratio detection method includes but is not limited to the following steps S500, S600, S700 and S800, with reference to Figure 7 :

[0081] Step S500, adjusting the detection light source to be in a spontaneous radiation state;

[0082] In this embodiment of the present invention, a detection light source is located at a remote site. The remote site has an idle port connected to the detection light source. The idle port at the remote site is a line-side port and is connected to the line-side port of the first site via an optical cable. Similarly, to obtain optical signals covering multiple channels, the detection light source is placed in a spontaneous emission state.

[0083] It can be understood that the detection light source in the embodiment of the present invention can also be composed of a spontaneous radiation source and an optical filter. The output end of the spontaneous radiation source is connected to the input end of the optical filter, and the output end of the optical filter is connected to the idle port. As for the hardware devices used for the spontaneous radiation source and the optical filter, please refer to the description of step S100, which will not be repeated here.

[0084] Step S600: Adjusting the signal width of the detection light source to a first width based on the spectrum bandwidth of the channel to be measured, obtaining the total power of the first channel at the optical performance monitoring point of the transmitting site and the total power of the second channel at the optical performance monitoring point of the receiving site, wherein the channel to be measured is an idle channel from the line-side port of the transmitting site to the line-side port of the receiving site, and the first width is no greater than the spectrum bandwidth of the channel to be measured;

[0085] Step S700: Adjusting the signal width of the detection light source to a second width, obtaining a first noise power at an optical performance monitoring point at a transmitting site and a second noise power at an optical performance monitoring point at a receiving site, wherein the second width is smaller than the first width and a center frequency of a signal corresponding to the second width is offset from a center frequency of a signal corresponding to the first width;

[0086] Step S800 : determining an optical signal-to-noise ratio of a channel to be measured according to the first channel total power, the second channel total power, the first noise power, and the second noise power.

[0087] Since the embodiment of the present invention cannot directly use the transmitting site as the measurement starting point, it is necessary to calculate the OSNR of the channel to be measured based on the OSNR of the paths at both ends. Specifically, the first site and the second site each have an optical performance monitoring point. Starting from the remote site, the signal width of the detection light source is set to the first width, and the first channel total power is obtained at the optical performance monitoring point of the transmitting site and the second channel total power is obtained at the optical performance monitoring point of the receiving site. Then, the signal width of the detection light source is adjusted to the second width, and the first noise power is obtained at the optical performance monitoring point of the transmitting site and the second noise power is obtained at the optical performance monitoring point of the receiving site. rate, thus obtaining two sets of data from the remote site. The first set of data is the total power and the first noise power of the first channel between the remote site and the transmitting site. The second set of data is the total power and the second noise power of the second channel between the remote site and the receiving site. Based on the first set of data and the above OSNR calculation formula, the OSNR from the line-side port of the remote site to the line-side port of the transmitting site can be obtained. Based on the second set of data and the above OSNR calculation formula, the OSNR from the line-side port of the transmitting site to the line-side port of the receiving site can be obtained. The OSNR obtained from the two sets of data can be subtracted to determine the OSNR of the channel to be measured, as shown in the following formula:

[0088]

[0089] Among them, OSNR 待测 Indicates the OSNR of the channel under test, OSNR2 indicates the OSNR from the line-side port of the remote site to the line-side port of the transmitting site, and OSNR3 indicates the OSNR from the line-side port of the remote site to the line-side port of the receiving site.

[0090] Reference Figure 8 , the above calculation process can be performed by following the steps below:

[0091] Step S810: determining a first signal power from a line-side port of a remote site to a line-side port of a transmitting site according to a first channel total power and a first noise power;

[0092] Step S820: determining a second signal power from the line-side port of the remote site to the line-side port of the receiving site according to the second channel total power and the second noise power;

[0093] Step S830 : determining an optical signal-to-noise ratio of the channel to be measured according to the spectrum bandwidth, the first signal power, the first noise power, the second signal power, and the second noise power of the channel to be measured.

[0094] Among them, the calculation method of determining the OSNR between the line side port of the remote site and the line side port of the transmitting site based on the spectrum bandwidth, the first signal power and the first noise power of the channel to be measured can refer to step S400. Similarly, the calculation method of determining the OSNR from the line side port of the remote site to the line side port of the receiving site based on the spectrum bandwidth, the second signal power and the second noise power of the channel to be measured can also refer to step S400. The detailed calculation process is not expanded here.

[0095] Similarly, to represent the OSNR of the actual service transmission path, it is necessary to consider the OSNR between the equipment-side add port at the transmitting site and the line-side port at the transmitting site, as well as the OSNR between the line-side port at the receiving site and the equipment-side drop port at the receiving site. Therefore, the above OSNR is modified according to the actual service transmission path:

[0096]

[0097] Among them, OSNR 业务 Indicates the OSNR of the actual transmission path of the service, OSNR 上路 Indicates the OSNR from the device-side add port at the originating site to the line-side port at the originating site. 下路 Indicates the OSNR of the dropped channel from the line-side port at the receiving site to the device-side port at the receiving site.

[0098] It is understandable that the path from the add port to the line-side port may pass through multiple components, such as several amplifier devices, several optical filters, etc. Therefore, the OSNR from the equipment-side add port at the transmitting site to the line-side port at the transmitting site may be composed of multiple OSNR segments. Similarly, the OSNR from the line-side port at the receiving site to the equipment-side drop port at the receiving site may also be composed of multiple OSNR segments, which is determined by the actual device connection method at the site.

[0099] The method for measuring OSNR at a remote site according to the embodiment of the present invention enables measurement of a channel to be measured at the remote site, solving the problem of being unable to measure the OSNR of the channel to be measured because the site has no idle ports.

[0100] Whether measuring the OSNR of the channel under test at a local or remote site, the total channel power and noise power of the channel under test can be obtained by adjusting the width of the detection light source. The signal optical power of the channel under test can be obtained, and the OSNR of the channel under test can be calculated. This enables optical performance monitoring of idle service paths, greatly improving network maintenance and management capabilities.

[0101] The optical signal-to-noise ratio detection method according to the embodiment of the present invention is described below using three practical examples:

[0102] Example 1: Measuring OSNR using a local port direct connection:

[0103] Reference Figure 9 Given the network line configuration diagram, this example requires measuring the OSNR of the idle channel from the transmitting site A, through the through-site B, to the receiving site C. In terms of hardware, the detection light source uses an EDFA type optical amplifier OA and a wavelength selective switch. Figure 9 OA#41 and WSS#41 are used to represent them respectively. WSS#41 is directly connected to the line-side port of the originating site A.

[0104] Assume that the center frequency of the idle channel to be measured is 192.1 THz and the width is 50 GHz.

[0105] Connect the D2 port of WSS#41 to the A2 port of WSS#21, and connect the detection light source from WSS#21 to the line side direction #2;

[0106] Turn on the optical amplifiers and wavelength selective switches on the channel to be tested. For WSS#51 and WSS#52, assign light with a center frequency of 192.1 THz and a bandwidth of 50 GHz to the connected ports.

[0107] Measuring the total channel power: Operate WSS#41 and assign the light with a center frequency of 192.1THz and a width of 50GHz to the D2 port of WSS#41. Read the power spectrum from the OPM at the receiving end site B and obtain the channel power with a center frequency of 192.1THz and a width of 50GHz. This is the total channel power, recorded as P OCh In this step, the first width set by WSS#41 is equal to the spectrum width of the channel to be measured, and the OPM is set at the output end of OA#61 at the receiving site B;

[0108] Measuring noise power: Operate WSS#41 and assign light with a center frequency of 192.0875 GHz and a width of 12.5 GHz to port D2 of WSS#41. Read the power spectrum from the OPM at receiving site B and obtain the channel power with a center frequency of 192.1125 GHz and a width of 12.5 GHz. This is the noise power, denoted as P. noise It can be seen that the second width set by WSS#41 in this step is 12.5 GHz.

[0109] According to the above channel total power and noise power, determine the OSNR of the channel to be measured and substitute it into the following formula:

[0110]

[0111] Among them, B OCh 50GHz, B noise 12.5GHz, B0.1 The frequency is 12.5 GHz. In this example, the OSNR calculated by the above formula is the OSNR between the line-side port of the transmitting site A and the line-side port of the receiving site C. 待测 .

[0112] Correct OSNR based on the actual transmission path of the service: For service light, if it travels from the originating site A to the receiving site C, it also needs to pass through the add-in part of the originating site A and the drop-in part of the receiving site C. Currently, there are many methods in the industry to obtain the OSNR of the add-in and drop-in parts, which will not be expanded here. Assume that the OSNR of the add-in part of the originating site A is OSNR 上路 , the OSNR of the drop channel at the receiving site C is OSNR 下路 , then the corrected OSNR between the add port (service board port) of the transmitting site A and the drop port (service board port) of the receiving site C is 业务 as follows:

[0113]

[0114] Example 2: Measuring OSNR on a local port with indirect connection:

[0115] Reference Figure 10 In the given network line configuration diagram, the difference between Example 2 and Example 1 is that there is no idle port on the line side of the originating site A, but there is an idle port on the device side of the add port. The detection light source is connected to the idle port on the device side of the add port of the originating site A. In terms of hardware, the detection light source also uses an EDFA type optical amplifier OA and a wavelength selective switch. Figure 10 In the figure, they are represented by OA#41 and WSS#41 respectively. The D1 port of WSS#41 is connected to the device-side add port of the originating site A, that is, the A3 port of WSS#32.

[0116] Assume that the center frequency of the idle channel to be measured is 192.1 THz and the width is 50 GHz.

[0117] Two power values are measured separately according to the method in the above example 1. According to the OSNR calculation formula, the OSNR between the equipment-side add port of the transmitting site A and the line-side port of the receiving site C can be obtained, which is recorded as OSNR1.

[0118] Correct the OSNR based on the actual service transmission path: Since OSNR1 already includes the OSNR of the upstream portion of the transmitting site A, we only need to obtain the OSNR of the downstream portion of the receiving site C:

[0119]

[0120] Example 3: Measuring OSNR on a remote port:

[0121] Reference Figure 11 In the given network line configuration diagram, the difference between Example 3 and Example 1 is that the detection light source is connected to an idle port at remote site D, which is the line-side port of remote site D. Similarly, the OSNR of the idle channel from the transmitting site A, through the pass-through site B, to the receiving site C is measured. In terms of hardware, the detection light source uses an EDFA type optical amplifier OA and a wavelength selective switch. Figure 11 OA#41 and WSS#41 are used to represent them respectively. WSS#41 is directly connected to the line-side port of remote site D.

[0122] Assume that the center frequency of the idle channel to be measured is 192.1 THz and the width is 50 GHz.

[0123] According to the method of the above-mentioned example 1, the OSNR between the line-side port of the remote site D and the line-side port of the transmitting site A can be obtained according to the OSNR calculation formula, which is recorded as OSNR2, and the OSNR between the line-side port of the remote site D and the line-side port of the receiving site B can be obtained, which is recorded as OSNR3.

[0124] Subtracting the two OSNRs obtained can determine the OSNR of the channel to be measured, as shown in the following formula:

[0125]

[0126] Correct OSNR based on the actual transmission path of the service: For service light, if it travels from the originating site A to the receiving site C, it also needs to pass through the add-in part of the originating site A and the drop-in part of the receiving site C. Assume that the OSNR of the add-in part of the originating site A is OSNR 上路 , the OSNR of the drop channel at the receiving site C is OSNR 下路 , then the corrected OSNR between the add port (service board port) of the transmitting site A and the drop port (service board port) of the receiving site C is 业务 as follows:

[0127]

[0128] An embodiment of the present invention further provides an optical signal-to-noise ratio detection system, comprising at least one processor and a memory for communicating with the at least one processor; the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the aforementioned optical signal-to-noise ratio detection method.

[0129] Take the example of a control processor and memory in an optical signal-to-noise ratio detection system that can be connected via a bus. The memory, as a non-transient computer-readable storage medium, can be used to store non-transient software programs and non-transient computer executable programs. In addition, the memory may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk memory, a flash memory device, or other non-transient solid-state memory device. In some embodiments, the memory may optionally include a memory remotely located relative to the control processor, and these remote memories may be connected to the optical signal-to-noise ratio detection system via a network. Examples of the above-mentioned networks include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0130] Those skilled in the art will appreciate that the above device structure does not limit the optical signal-to-noise ratio detection system, and may include more or fewer components, or a combination of certain components, or different component arrangements.

[0131] The embodiment of the present invention further provides a computer-readable storage medium, which stores computer-executable instructions. The computer-executable instructions are executed by one or more control processors. For example, the execution of the control processors can enable the one or more control processors to perform the optical signal-to-noise ratio detection method in the above method embodiment, for example, to perform the above-described Figure 1 Steps S100 to S400 of the method, Figure 4 Steps S110 to S120 of the method, Figure 5 Steps S410 to S420 of the method, Figure 6 Steps S430 to S450 of the method, Figure 7 Steps S500 to S800 of the method and Figure 8 Method steps S810 and S830 in .

[0132] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, i.e., they may be located in one place or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of this embodiment.

[0133] Those skilled in the art will appreciate that all or some of the steps and systems in the method disclosed above can be implemented as software, firmware, hardware, and appropriate combinations thereof. Some physical components or all physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or implemented as hardware, or implemented as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, and the computer-readable medium can include computer storage media (or non-transitory media) and communication media (or temporary media). As known to those skilled in the art, the term computer storage media is included in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data) and is volatile and non-volatile, removable, and non-removable. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory, or other memory technology, CD-ROM, digital versatile disks (DVD), or other optical disk storage, magnetic cassettes, magnetic tapes, disk storage, or other magnetic storage devices, or any other medium that can be used to store desired information and can be accessed by a computer. Furthermore, as is well known to those skilled in the art, communication media typically embodies computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0134] The above is a specific description of the preferred implementation of the present application, but the present application is not limited to the above implementation mode. Technical personnel familiar with the field can also make various equivalent modifications or substitutions without violating the spirit of the present application. These equivalent modifications or substitutions are all included in the scope defined by the claims of the present application.

Claims

1. An optical signal-to-noise ratio detection method, applied to an optical signal-to-noise ratio detection system, the optical signal-to-noise ratio detection system comprising a detection light source disposed at a transmitting site, the output end of the detection light source being connected to a line-side port of the transmitting site, the optical signal-to-noise ratio detection method comprising: Adjusting the detection light source to be in a spontaneous radiation state; Adjusting the signal width of the detection light source to a first width based on the spectrum bandwidth of the channel to be measured, and obtaining the total channel power at the optical performance monitoring point of the receiving site, wherein the channel to be measured is an idle channel from the line-side port of the transmitting site to the line-side port of the receiving site, and the first width is not greater than the spectrum bandwidth of the channel to be measured; Adjusting the signal width of the detection light source to a second width, and obtaining the noise power at the optical performance monitoring point of the receiving end site, wherein the second width is smaller than the first width and a center frequency of a signal corresponding to the second width is staggered from a center frequency of a signal corresponding to the first width; The optical signal-to-noise ratio of the channel to be measured is determined according to the total channel power and the noise power.

2. The optical signal-to-noise ratio detection method according to claim 1, wherein: The detection light source includes a spontaneous radiation source and an optical filter, and the output end of the spontaneous radiation source is connected to the input end of the optical filter.

3. The optical signal-to-noise ratio detection method according to claim 2, wherein: The spontaneous radiation source is an erbium-doped fiber amplifier, and the optical filter is a wavelength selective switch.

4. The optical signal-to-noise ratio detection method according to claim 3, wherein: The step of adjusting the detection light source to be in a spontaneous radiation state includes: placing the spontaneous radiation source in a spontaneous radiation state; The spontaneous radiation power of the spontaneous radiation source is adjusted to be the same as the service access power of the channel to be measured.

5. The optical signal-to-noise ratio detection method according to claim 1, wherein: The output end of the detection light source is directly connected to the line side port of the transmitting site, and determining the optical signal-to-noise ratio of the channel to be measured according to the total power of the channel and the noise power includes: Determine the signal optical power of the channel to be measured according to the total channel power and the noise power; The optical signal-to-noise ratio of the channel to be measured is determined according to the spectrum bandwidth of the channel to be measured, the signal optical power, and the noise power.

6. The optical signal-to-noise ratio detection method according to claim 1, wherein: The output end of the detection light source is connected to the line-side port of the transmitting site through the device-side add port of the transmitting site, and the determining the optical signal-to-noise ratio of the channel to be measured according to the total channel power and the noise power includes: Determine the signal optical power of the channel to be measured according to the total channel power and the noise power; Obtaining an added optical signal-to-noise ratio from a device-side added port of the originating site to a line-side port of the originating site; The optical signal-to-noise ratio of the channel to be measured is determined according to the spectrum bandwidth of the channel to be measured, the added optical signal-to-noise ratio, the signal optical power, and the noise power.

7. An optical signal-to-noise ratio detection method, applied to an optical signal-to-noise ratio detection system, the optical signal-to-noise ratio detection system comprising a detection light source disposed at a remote site, the output end of the detection light source being connected to a line-side port of the remote site, the optical signal-to-noise ratio detection method comprising: Adjusting the detection light source to be in a spontaneous radiation state; Adjusting the signal width of the detection light source to a first width according to the spectrum bandwidth of the channel to be measured, obtaining the total power of the first channel at the optical performance monitoring point of the transmitting site and the total power of the second channel at the optical performance monitoring point of the receiving site, wherein the channel to be measured is an idle channel from the line-side port of the transmitting site to the line-side port of the receiving site, and the first width is no greater than the spectrum bandwidth of the channel to be measured; Adjusting the signal width of the detection light source to a second width, obtaining a first noise power at an optical performance monitoring point of the transmitting site and a second noise power at an optical performance monitoring point of the receiving site, wherein the second width is smaller than the first width and a center frequency of a signal corresponding to the second width is staggered from a center frequency of a signal corresponding to the first width; The optical signal-to-noise ratio of the channel to be measured is determined according to the first channel total power, the second channel total power, the first noise power, and the second noise power.

8. The optical signal-to-noise ratio detection method according to claim 7, wherein: The determining the optical signal-to-noise ratio of the channel to be measured according to the first channel total power, the second channel total power, the first noise power, and the second noise power includes: Determine a first signal power from the line-side port of the remote site to the line-side port of the originating site according to the first channel total power and the first noise power; Determine a second signal power from the line side port of the remote site to the line side port of the receiving site according to the second channel total power and the second noise power; An optical signal-to-noise ratio (OSNR) of the channel to be measured is determined according to the spectrum bandwidth of the channel to be measured, the first signal power, the first noise power, the second signal power, and the second noise power.

9. An optical signal-to-noise ratio detection system, characterized in that: The invention comprises at least one processor and a memory for communicating with the at least one processor; the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the optical signal-to-noise ratio detection method according to any one of claims 1 to 6 or the optical signal-to-noise ratio detection method according to any one of claims 7 to 8.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the optical signal-to-noise ratio detection method according to any one of claims 1 to 6 or the optical signal-to-noise ratio detection method according to any one of claims 7 to 8.

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