CN113572520B

CN113572520B - Optical network terminal and method for determining port connected with optical network terminal

Info

Publication number: CN113572520B
Application number: CN202010358089.4A
Authority: CN
Inventors: 董振华; 曾小飞; 董小龙; 金超
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-04-29
Filing date: 2020-04-29
Publication date: 2022-10-04
Anticipated expiration: 2040-04-29
Also published as: WO2021218146A1; CN113572520A

Abstract

The application provides an optical network terminal and a method for determining a port connected with the optical network terminal, and relates to the technical field of optical fiber communication. The optical network terminal includes: the optical fiber interface, the light receiving subassembly, the optical transmission subassembly, first filter and second filter, be provided with first filter between optical fiber interface and the optical transmission subassembly, and the optical transmission subassembly is located the transmission light way of first filter, first filter is used for the last optical signal transmission to the optical fiber interface that the optical transmission subassembly sent, the light receiving subassembly through with first filter, the cooperation of second filter realizes receiving test light signal and business light signal, the wavelength of test light signal is inequality with the wavelength of business light signal. By adopting the method and the device, the realization difficulty of the ONT can be reduced.

Description

Optical network terminal and method for determining port connected with optical network terminal

Technical Field

The present application relates to the field of optical fiber communication technologies, and in particular, to an optical network terminal and a method for determining a port to which the optical network terminal is connected.

Background

With the development of Optical fiber communication technology, passive Optical Networks (PONs) are rapidly developed and deployed on a large scale. The PON is a point-to-multipoint system, and is formed by sequentially connecting an Optical Line Terminal (OLT), an Optical Distribution Network (ODN), and an Optical Network Terminal (ONT). The ODN is a passive optical network, which is composed of passive devices, and mainly includes an optical fiber and a Splitter (Splitter). Because the ODN realizes transmission of optical signals from the OLT to the ONTs by a point-to-point connection method, the ODN has the characteristics of wide coverage area, huge data of branch optical paths, complex scene and the like, and in addition, the ODN is not powered on, fault location troubleshooting of the ODN is difficult, the accuracy of fault location is particularly important, and a port where the ONTs are connected in the ODN needs to be accurately identified to realize fault location.

In the related art, in order to identify the ports of the ONTs connected in the ODN, a reflection grating is disposed at the port of each optical splitter of the ODN, for one optical splitter, reflection gratings that reflect optical signals with different wavelengths are disposed at different ports of the optical splitter, for optical splitters in the i-th (i is greater than or equal to 2) stage optical splitter, the wavelengths of the optical signals respectively reflected by the reflection gratings disposed at the ports of each of the two optical splitters are λ 1 to λ n, and n is the number of ports of each optical splitter in the i-th stage optical splitter. And at the ONT side, an external device is externally connected to the ONT, and the external device is used for detecting the power of the received test optical signal, so that the test optical signal with multiple wavelengths can be input into the ODN, and the multiple wavelengths consist of the wavelengths of the optical signals which can be reflected by the reflection grating arranged at the port of each optical splitter in the ODN. Thus, if the power of the test optical signal with a certain wavelength received by the external device of a certain ONT is the minimum, it indicates that the test optical signal with the wavelength is reflected by the reflection grating, and it can be determined that the port where the reflection grating corresponding to the wavelength is located is the port connected by the ONT in the ODN.

Because each ONT needs to be connected with an external device to determine the port to which the ONT is connected in the ODN, the implementation difficulty of the ONT is high.

Disclosure of Invention

The embodiment of the application provides an optical network terminal and a method for determining a port connected with the optical network terminal, and by adopting the method, the implementation difficulty of the ONT can be reduced, and the port connected with the ONT in an ODN can be determined efficiently.

In a first aspect, an ONT is provided, which includes an optical fiber interface, a light receiving module, a light emitting module, a first filter, and a second filter. A first filter is arranged between the optical fiber interface and the light emission component, the light emission component is positioned on a transmission light path of the first filter, and the first filter is used for transmitting an uplink light signal sent by the light emission component to the optical fiber interface; the optical receiving component is matched with the first filter and the second filter to receive the test optical signal and the service optical signal, and the wavelength of the test optical signal is different from that of the service optical signal. The test optical signal is used to determine the port to which the ONT is connected in the ODN and the level of the optical splitter to which the port to which the ONT is connected in the ODN belongs. Thus, the reception of the test optical signal and the service optical signal can be realized by one ONT.

In a possible implementation manner, the light receiving component and the second filter are positioned on a reflected light path of the first filter; the first filter is also used for reflecting the test optical signal and the service optical signal received by the optical fiber interface to the second filter; the second filter is used for transmitting the test optical signal and the service optical signal to the optical receiving component.

In the solution shown in the present application, the light receiving component and the second filter are located on the reflected light path of the first filter. The first filter plate is used for transmitting the uplink optical signal sent by the light emission assembly to the optical fiber interface and reflecting the test optical signal and the downlink service optical signal received by the optical fiber interface to the second filter plate. The second filter segment may be configured to transmit the test optical signal and the downstream service optical signal to the optical receive module. Therefore, the receiving of the test optical signal and the service optical signal can be realized through one ONT, and the realization difficulty of the ONT is reduced.

In one possible implementation, the light receiving assembly includes a first light receiving assembly and a second light receiving assembly; the second filter is positioned on the transmission light path of the first filter and positioned between the first filter and the light emission component; the first light receiving component is positioned on the reflected light path of the first filter; the second light receiving component is positioned on a reflection light path of the second filter; the first filter is also used for reflecting the test optical signal received by the optical fiber interface to the first optical receiving component and transmitting the service optical signal received by the optical fiber interface to the second filter; the second filter is used for reflecting the service optical signal received by the optical fiber interface to the second optical receiving component, and the second filter is also used for transmitting the uplink optical signal sent by the light emitting component to the first filter.

Therefore, one ONT comprises two optical receiving components which are respectively used for receiving the downlink service optical signal and the test optical signal, so that the test optical signal and the downlink service optical signal can be received by one ONT, and the implementation difficulty of the ONT is reduced.

In one possible implementation, the light receiving assembly includes a first light receiving assembly and a second light receiving assembly; the second filter is positioned on the transmission light path of the first filter and positioned between the first filter and the light emission component; the second light receiving component is positioned on the reflected light path of the first filter; the first light receiving component is positioned on a reflection light path of the second filter; the first filter is also used for reflecting the service optical signal received by the optical fiber interface to the second optical receiving component and transmitting the test optical signal received by the optical fiber interface to the second filter; the second filter is used for reflecting the test optical signals received by the optical fiber interface to the first optical receiving assembly, and the second filter is also used for transmitting the uplink optical signals sent by the optical transmitting assembly to the first filter.

In a possible implementation manner, the ONT further includes a processor, and the processor is electrically connected to the light receiving component; the processor is configured to determine a first difference between each total power of the received test optical signal and the service optical signal and a power of the service optical signal, determine a first wavelength of the received test optical signal when the first difference is smaller than a first value, and determine a port of the ODN connected to the ONT as a port corresponding to the first wavelength; or the processor is configured to determine a second difference between the maximum total power and each total power of the received test optical signal and the traffic optical signal, and determine a first wavelength of the received test optical signal when the second difference is greater than a second value; determining that a port of an ODN connected to the ONT is a port corresponding to the first wavelength, where the maximum total power is a maximum value of multiple total powers of the received test optical signal and the service optical signal.

In the solution shown in the present application, the ONT further includes a processor, and the processor is electrically connected to the light receiving assembly. In order to determine the ports to which the ONTs are connected in the ODN, each port of the optical splitter in the ODN is provided with a reflective grating, and the wavelengths of the optical signals that can be reflected by the reflective gratings provided at each port are different. Test optical signals with various wavelengths are input into the ODN, and the various wavelengths are composed of the wavelengths of the optical signals capable of being reflected by the reflection grating arranged at each port of the optical splitter of the ODN. The optical receiving component of the ONT may detect the total power of the test optical signal and the service optical signal received each time. The processor may retrieve the pre-stored power of the traffic optical signal, which may be the power detected by the optical receiving component when no test optical signal is input to the ODN. The processor may take a difference between each total power and the power of the traffic optical signal to obtain a first difference corresponding to each total power. The processor may then determine a first difference value corresponding to each total power and a first value, and if the first difference value corresponding to the total power is smaller than the first value for a certain total power, may determine a first wavelength of the received test optical signal to which the total power belongs. And the processor enables the port connected by the ONT in the ODN to be a port corresponding to the first wavelength.

Alternatively, the optical receiving component of the ONT may detect the total power of the test optical signal and the service optical signal received each time. The processor may determine a maximum value (i.e., a maximum total power) of the detected plurality of total powers, and then calculate a second difference value between the maximum value and each detected total power to obtain a second difference value corresponding to each total power. The processor may determine a magnitude of a second difference and a second value for each total power. The processor determines a first wavelength of the received test light signal when a second difference corresponding to the total power is greater than a second value. In this way, the port to which the ONT is connected in the ODN can be determined.

In a possible implementation manner, the processor is further configured to determine a third difference value between the first total power and the second total power, where the first total power and the second total power are powers when the test optical signal received by the optical receiving component includes an optical signal with an offset wavelength; when the first total power is corresponded, the optical signal input to the ODN comprises a test optical signal with a target wavelength and an optical signal with an offset wavelength; when the second total power is corresponded, the optical signal input into the ODN comprises the optical signal with the offset wavelength and does not comprise the test optical signal with the target wavelength; the offset wavelength is a wavelength obtained by offsetting a target value by a target wavelength, the power of a test optical signal with the target wavelength after being reflected at a port corresponding to the target wavelength of a first-stage optical splitter of the ODN is greater than or equal to a threshold value for generating a Brillouin amplification effect, the power of the test optical signal with the target wavelength after being reflected at a port corresponding to the target wavelength of a second-stage optical splitter of the ODN is smaller than the threshold value for generating the Brillouin amplification effect, and the target wavelength is one of the first wavelengths when the first wavelengths include a plurality of wavelengths; if the third difference is greater than or equal to the target threshold, determining that the port corresponding to the target wavelength belongs to the first-stage optical splitter of the ODN; and if the third difference is smaller than the target threshold, determining that the port corresponding to the target wavelength belongs to the second-stage optical splitter of the ODN.

In the solution shown in the present application, the processor may further obtain powers detected by the optical receiving component when the received test optical signal includes an optical signal with an offset wavelength, that is, the first total power and the second total power. When the detected power is the first total power, the optical signal with the offset wavelength included in the test optical signal received by the optical receiving component is an optical signal when the test optical signal with the target wavelength and the optical signal with the offset wavelength are input to the ODN together, and when the detected power is the second total power, the optical signal with the offset wavelength included in the test optical signal received by the optical receiving component is an optical signal when the test optical signal with the target wavelength is not input to the ODN. Specifically, the test optical signal with the target wavelength may be amplified at a first port of a first-stage optical splitter of the ODN, while the optical signal with the offset wavelength is not amplified at a second port of a second-stage optical splitter of the ODN, and reflection gratings disposed at the first port and the second port reflect the test optical signal with the target wavelength. The target wavelength is one of the first wavelengths. The processor may determine a third difference between the first total power and the second total power, and determine a magnitude of the third difference and the target threshold. If the third difference is greater than or equal to the target threshold, it may be determined that the port corresponding to the target wavelength belongs to the first-stage optical splitter of the ODN, and it may be determined that the port corresponding to a wavelength other than the target wavelength in the first wavelength belongs to the second-stage optical splitter of the ODN. If the third difference is smaller than the target threshold, it may be determined that the port corresponding to the target wavelength belongs to the second-stage optical splitter of the ODN, and it may be determined that the port corresponding to the wavelength other than the target wavelength in the first wavelength belongs to the first-stage optical splitter of the ODN. In this way, the level of the splitter to which the port to which the ONT is connected in the ODN belongs can be accurately determined.

In a possible implementation manner, the ONT further includes a processor, and the processor is electrically connected to the first light receiving component; the processor is configured to determine a fourth difference between the maximum power and each power of the test optical signal received by the first optical receiving component, and when it is determined that the fourth difference is greater than the second value, determine a first wavelength of the test optical signal received by the first optical receiving component, determine that a port of the ODN connected to the ONT is a port corresponding to the first wavelength, and determine that the maximum power is a maximum value among the multiple powers of the received test optical signal.

In the solution shown in the present application, the ONT further includes a processor, and the processor is electrically connected to the light receiving module, and certainly, the processor is electrically connected to the first light receiving module. In order to determine the ports to which the ONTs are connected in the ODN, each port of the optical splitter in the ODN is provided with a reflective grating, and the wavelength corresponding to the reflective grating provided in each port is different (that is, the wavelength of the optical signal that can be reflected by each reflective grating is different). Test optical signals with various wavelengths are input into the ODN, and the various wavelengths consist of wavelengths corresponding to reflection gratings arranged at each port of an optical splitter of the ODN. The first optical receiving component of the ONT may detect the power of the test optical signal received each time. The processor may determine a maximum value among a plurality of powers of the test optical signal received by the first optical receiving assembly and then calculate a fourth difference value of the maximum power and each power of the test optical signal received by the first optical receiving assembly. The processor judges the magnitude of a fourth difference value corresponding to each power and the magnitude of a second numerical value, and determines a first wavelength of the test optical signal received by the first optical receiving assembly corresponding to the power when the fourth difference value corresponding to a certain power is larger than the second numerical value. The processor may then determine that the port to which the ONT is connected in the ODN is the port corresponding to the first wavelength. The port corresponding to the first wavelength is a port in the ODN, where a reflection grating for reflecting the test optical signal of the first wavelength is disposed. In this way, the port to which the ONT is connected in the ODN can be determined.

In a possible implementation, the light emitting component is located on the reflected light path of the first filter. The light receiving assembly and the second filter are positioned on the transmission light path of the first filter. The first filter plate is used for reflecting the uplink optical signal sent by the light emission component to the optical fiber interface, and can also be used for transmitting the test optical signal and the service optical signal received by the optical fiber interface to the second filter plate. The second filter segment may be for transmitting the test optical signal and the service optical signal to the optical receiving component. In this way, the optical receiving module can receive the test optical signal and the service optical signal. The optical receiving component may detect a total power of the received test optical signal and the traffic optical signal. The service optical signal is a downlink service optical signal. Therefore, the receiving of the test optical signal and the service optical signal can be realized through one ONT, and the realization difficulty of the ONT is reduced.

In a possible implementation manner, the light receiving assembly includes a first light receiving assembly and a second light receiving assembly, and the second filter is located on a transmission light path of the first filter and located between the first filter and the second light receiving assembly. The first light receiving component is positioned on the reflected light path of the second filter, and the light emitting component is positioned on the reflected light path of the first filter. The first filter is used for transmitting the uplink optical signal transmitted by the optical transmission component to the optical fiber interface through reflection, so that normal uplink service of the ONT is realized. The first filter is also used for transmitting the test optical signal and the service optical signal received by the optical fiber interface to the second filter. The second filter is used for transmitting the service optical signal received by the optical fiber interface to the second optical receiving component. The second filter is also used for reflecting the test optical signal received by the optical fiber interface to the first optical receiving component. Thus, the second optical receiving component can receive the service optical signal and perform normal downlink service, and the first optical receiving component can receive the test optical signal and detect the power of the received test optical signal. Therefore, the receiving of the test optical signal and the service optical signal can be realized through one ONT, and the realization difficulty of the ONT is reduced.

In a possible implementation manner, the light receiving assembly includes a first light receiving assembly and a second light receiving assembly, and the second filter is located on a transmission light path of the first filter and located between the first filter and the first light receiving assembly. The second light receiving component is positioned on the reflected light path of the second filter, and the light emitting component is positioned on the reflected light path of the first filter. The first filter is used for transmitting the uplink optical signal emitted by the optical transmission component to the optical fiber interface through reflection, so that normal uplink service of the ONT is realized. The first filter is also used for transmitting the test optical signal and the service optical signal received by the optical fiber interface to the second filter. The second filter is used for reflecting the service optical signal received by the optical fiber interface to the second optical receiving component. The second filter is also used for transmitting the test optical signal received by the optical fiber interface to the first optical receiving component. Thus, the second optical receiving component can receive the service optical signal to perform normal downlink service, and the first optical receiving component can receive the test optical signal to detect the power of the received test optical signal. Therefore, the receiving of the test optical signal and the service optical signal can be realized through one ONT, and the realization difficulty of the ONT is reduced.

In a possible implementation manner, the light receiving assembly includes a first light receiving assembly and a second light receiving assembly, and the second filter is located on a transmission light path of the first filter and located between the first filter and the first light receiving assembly. The second light receiving component is positioned on the reflection light path of the first filter, and the light emitting component is positioned on the reflection light path of the second filter. The second filter is used for reflecting the uplink optical signal transmitted by the light emission component to the first filter, and the first filter is used for transmitting the uplink optical signal transmitted by the light emission component to the optical fiber interface, so that normal uplink service of the ONT is realized. The first filter is also used for reflecting the service optical signals received by the optical fiber interface to the second optical receiving component, and the first filter is also used for transmitting the test optical signals received by the optical fiber interface to the second filter. The second filter is also used for transmitting the test optical signal received by the optical fiber interface to the first optical receiving component. Thus, the second optical receiving component can receive the service optical signal to perform normal downlink service, and the first optical receiving component can receive the test optical signal to detect the power of the received test optical signal. Therefore, the receiving of the test optical signal and the service optical signal can be realized through one ONT, and the realization difficulty of the ONT is reduced.

In a possible implementation manner, the light receiving assembly includes a first light receiving assembly and a second light receiving assembly, and the second filter is located on a transmission light path of the first filter and located between the first filter and the second light receiving assembly. The first light receiving component is positioned on the reflection light path of the first filter, and the light emitting component is positioned on the reflection light path of the second filter. The second filter is used for reflecting the uplink optical signal transmitted by the light emission component to the first filter, and the first filter is used for transmitting the uplink optical signal transmitted by the light emission component to the optical fiber interface, so that normal uplink service of the ONT is realized. The first filter is also used for reflecting the test optical signal received by the optical fiber interface to the first optical receiving component, and the first filter is also used for transmitting the service optical signal received by the optical fiber interface to the second filter. The second filter is also used for transmitting the service optical signal received by the optical fiber interface to the second optical receiving component. Thus, the second optical receiving component can receive the service optical signal and perform normal downlink service, and the first optical receiving component can receive the test optical signal and detect the power of the received test optical signal. Therefore, the receiving of the test optical signal and the service optical signal can be realized through one ONT, and the realization difficulty of the ONT is reduced.

In a second aspect, a tunable laser is provided, where the tunable laser includes a laser, a beam splitter, a first optical modulator, and a light combiner, where the beam splitter includes a first light outlet and a second light outlet; the laser is used for outputting test optical signals with various wavelengths; the beam splitter is positioned between the laser and the first light modulator, the beam splitter is positioned at a light outlet of the laser, and the first light modulator is positioned at a first light outlet of the beam splitter; the beam splitter is used for dividing a test optical signal with a target wavelength entering the beam splitter into a first test optical signal and a second test optical signal, and outputting the first test optical signal and the second test optical signal through a first light outlet and a second light outlet respectively, wherein the target wavelength belongs to multiple wavelengths; the light combiner is positioned at the light outlet of the first light modulator and the second light outlet of the beam splitter; the first optical modulator is used for shifting the wavelength of the first test optical signal by a target value to obtain an optical signal with a shifted wavelength, the optical combiner is used for combining a second test optical signal and the optical signal with the shifted wavelength and outputting the combined optical signal, the power of the second test optical signal after being reflected at a first port of a first-stage optical splitter of the ODN is greater than or equal to a threshold value for generating a Brillouin amplification effect, the power of the second test optical signal after being reflected at a second port of a second-stage optical splitter of the ODN is smaller than the threshold value for generating the Brillouin amplification effect, the center wavelength of a reflection grating arranged at the first port is a target wavelength, and the center wavelength of the reflection grating arranged at the second port is the target wavelength. Therefore, two paths of optical signals can be generated by the wavelength-adjustable laser, one path of optical signal is a second test optical signal, and the other path of optical signal is an offset wavelength optical signal obtained by offsetting the wavelength of the second test optical signal.

In one possible implementation, the tunable wavelength laser further includes a second optical modulator; the second light modulator is positioned between the second light outlet of the beam splitter and the light combiner; the second optical modulator is used to adjust the power of the second test optical signal entering the second optical modulator. In this way, the power of the second test optical signal can be flexibly controlled.

In a third aspect, there is provided a system for determining the topology of an optical access network, the system comprising a tuneable wavelength laser, an ONT, and a wavelength division multiplexer or coupler, wherein: the tunable wavelength laser is the tunable wavelength laser of the second aspect; the ONT is the ONT of the first aspect; the wavelength division multiplexer or coupler is used to combine the service optical signal and the test optical signal into a bundle of optical signals. In this way, the topology of the optical access network can be determined efficiently.

In one possible implementation, the system further includes an ODN; the ODN is connected with the wavelength division multiplexer or the coupler and the ONT; the ODN comprises a first-stage optical splitter and a second-stage optical splitter, wherein each port of the first-stage optical splitter and each port of the second-stage optical splitter are provided with a reflection grating, and the wavelength of an optical signal which can be reflected by the reflection grating is different from the wavelength of a service optical signal. Therefore, the topology of the optical access network can be determined by arranging the reflection grating at the port of the optical splitter of the ODN, and the efficiency of determining the topology of the optical access network is improved.

In a possible implementation manner, each port of the first-stage optical splitter and each port of each optical splitter of the second-stage optical splitter are provided with a reflection grating with the same wavelength; for any one of the first-stage optical splitter and the second-stage optical splitter, each port of the optical splitter adopts a reflection grating with different wavelengths. Therefore, as the port of each optical splitter is provided with the reflection grating with the same wavelength, the number of the wavelengths of the test optical signals can be reduced, and the wavelength adjusting range of the wavelength-adjustable laser can be further reduced.

In one possible implementation, the tunable wavelength laser is disposed in the OLT.

In a fourth aspect, a method for outputting a test optical signal is provided, which is applied to the tunable laser of the second aspect; the method comprises the following steps: outputting a test optical signal with a target wavelength, wherein the target wavelength belongs to the wavelengths of various test optical signals which can be output by the tunable wavelength laser; dividing the test optical signal with the target wavelength into two optical signals, wherein the two optical signals comprise a first test optical signal and a second test optical signal; carrying out wavelength offset processing on the first test optical signal to obtain an optical signal with offset wavelength; and synthesizing a second test optical signal and an optical signal with the offset wavelength, and outputting the synthesized optical signal, wherein the power of the second test optical signal after being reflected at a port corresponding to the target wavelength of the first-stage optical splitter of the ODN is greater than or equal to the threshold value for generating the Brillouin amplification effect, and the power of the second test optical signal after being reflected at a port corresponding to the target wavelength of the second-stage optical splitter of the ODN is less than the threshold value for generating the Brillouin amplification effect.

According to the scheme, the adjustable wavelength laser can output the test optical signal with the target wavelength, the adjustable wavelength laser can divide the test optical signal with the target wavelength into two optical signals, and the two optical signals can comprise a first test optical signal and a second test optical signal. The wavelengths of the first test optical signal and the second test optical signal are both target wavelengths. The tunable laser may shift a target wavelength of the first test optical signal by a target value to obtain an optical signal with a shifted wavelength. The tunable wavelength laser may output the second test optical signal and/or the optical signal at the offset wavelength, i.e. to the ODN. The power of the second test optical signal after being reflected at the port corresponding to the target wavelength of the first-stage optical splitter of the ODN is greater than or equal to the threshold value for generating the brillouin amplification effect, and the power of the second test optical signal after being reflected at the port corresponding to the target wavelength of the second-stage optical splitter of the ODN is less than the threshold value for generating the brillouin amplification effect. That is, the second test optical signal is used to amplify the optical signal with the offset wavelength at the port corresponding to the target wavelength of the first-stage optical splitter of the ODN, and is used to not amplify the optical signal with the offset wavelength at the port corresponding to the target wavelength of the optical splitter except the first optical splitter in the ODN. In this way, if the port to which the ONT is connected is the port corresponding to the target wavelength of the first-stage optical splitter, the power of the test optical signal detected by the ONT is the power of the amplified optical signal with the offset wavelength, and the detected power is relatively high.

In one possible implementation, the method further includes: adjusting the power of the second test optical signal; combining the second test optical signal and the offset wavelength optical signal, comprising: and synthesizing the optical signal with the offset wavelength and the second test optical signal after the power is adjusted. In this way, the power of the second test optical signal can be flexibly adjusted.

In a possible implementation manner, the target wavelength is a wavelength corresponding to a port of the target optical network terminal ONT connected in the optical distribution network ODN; the test optical signal of the target wavelength is used for testing the level of the optical splitter to which the port connected by the target ONT in the ODN belongs, and the target wavelength is one of the wavelengths corresponding to the port connected by the target ONT in the ODN; before synthesizing the second test optical signal and the optical signal with the offset wavelength, the method further comprises: receiving a wavelength output instruction sent by the OLT, wherein the wavelength output instruction is used for indicating to output a test optical signal of a target wavelength; the method also comprises receiving a closing instruction of a second test optical signal sent by the OLT; the output of the second test optical signal is stopped, and an optical signal of an offset wavelength is output.

In the solution shown in this application, the current OLT knows that a wavelength corresponding to a port where a target ONT (any ONT) is connected in the ODN is a target wavelength, and at this time, the OLT may send a wavelength output instruction to the tunable wavelength laser, where the wavelength output instruction is used to instruct the tunable wavelength laser to output a test optical signal of the target wavelength. Therefore, the adjustable wavelength laser can output the test optical signal with the target wavelength, and the adjustable wavelength laser can combine the second test optical signal and the optical signal with the offset wavelength into one optical signal and output the optical signal. The tunable wavelength laser may further receive a shutdown instruction of the second test optical signal sent by the OLT. The tunable wavelength laser may turn off the output of the second test optical signal and output only the optical signal at the offset wavelength to the ODN. In this way, the test optical signal can be flexibly output and data can be provided for identifying the level of the optical splitter to which the port to which the ONT is connected in the ODN belongs.

In a possible implementation manner, before outputting the test optical signal of the target wavelength, the method further includes: receiving a closing instruction of an optical signal with offset wavelength sent by the OLT and an instruction for sending out various testing optical signals, closing the output of the optical signal with offset wavelength, and outputting various testing optical signals according to the preset wavelength sequence of the testing optical signals, wherein the various testing optical signals are used for determining the port of the target ONT connected in the ODN.

According to the scheme, the OLT can send a closing instruction of an optical signal with offset wavelength and send instructions of various test optical signals to the adjustable wavelength laser. The tunable wavelength laser may receive both commands and then turn off the output of the optical signal at the offset wavelength. The tunable wavelength laser may emit multiple test optical signals according to a preset wavelength sequence (which may be issued to the tunable wavelength laser by an OLT through an instruction or may be preconfigured in the tunable wavelength laser). In this way, the tunable wavelength laser may output only the second test optical signal of each of the beams of test optical signals. The optical receiving component of the ONT detects the total power of the second test optical signal and the service optical signal. In this way, data may be provided for the port that determines the ONT is connected in the ODN.

In a fifth aspect, a method for determining a port to which an optical network terminal is connected is provided, where the method is applied to the ONT of the first aspect or the system of the third aspect, and the method includes: acquiring a difference value between first power and second power corresponding to a target ONT, wherein the wavelength corresponding to a port connected by the target ONT in an Optical Distribution Network (ODN) is a first wavelength, and one wavelength included in the first wavelength is a target wavelength; the offset wavelength is a wavelength obtained by offsetting the target wavelength by the target value, and the first power and the second power are powers when the optical signal received by the target ONT comprises the optical signal with the offset wavelength; when the optical signal corresponds to the first power, the optical signal input to the optical distribution network ODN together with the optical signal with the offset wavelength includes a test optical signal with a target wavelength; when the second power is corresponded, the optical signal input into the ODN includes an optical signal with an offset wavelength and does not include a test optical signal with a target wavelength, the power of the test optical signal with the target wavelength after being reflected at a port corresponding to the target wavelength of the first-stage optical splitter of the ODN is greater than or equal to a threshold value for generating a brillouin amplification effect, and the power of the test optical signal with the target wavelength after being reflected at a port corresponding to the target wavelength of the second-stage optical splitter of the ODN is smaller than the threshold value for generating the brillouin amplification effect; if the difference is larger than or equal to the target threshold, determining that the port corresponding to the target wavelength belongs to a first-stage optical splitter of the ODN; and if the difference is smaller than the target threshold, determining that the port corresponding to the target wavelength belongs to the second-stage optical splitter of the ODN.

In the solution shown in this application, the target ONT may obtain the first power and the second power, and when the target ONT detects the first power, the optical signal input to the ODN by the tunable wavelength laser is the test optical signal with the target wavelength and the optical signal with the offset wavelength. Thus, the optical signals input into the ODN include a test optical signal at a target wavelength and an optical signal at an offset wavelength. When the target ONT detects the second power, the optical signal input into the ODN by the tunable wavelength laser is an optical signal with an offset wavelength, and thus the optical signal input into the ODN is an optical signal with an offset wavelength. The targeted ONT may determine a difference between the first power and the second power. The targeted ONT may determine a magnitude of a difference between the first power and the second power and a targeted threshold. If the difference between the first power and the second power is greater than or equal to the target threshold, the target ONT may determine that a port corresponding to the target wavelength belongs to the first stage optical splitter of the ODN, and may determine that a port corresponding to another wavelength other than the target wavelength in the first wavelength belongs to the second stage optical splitter of the ODN. If the difference is smaller than the target threshold, the target ONT may determine that the port corresponding to the target wavelength belongs to the second-stage optical splitter of the ODN, and may determine that the port corresponding to another wavelength other than the target wavelength in the first wavelength belongs to the first-stage optical splitter of the ODN. The reason is that the difference between the first power and the second power is relatively large, which indicates that the intensity of the optical signal with the offset wavelength received by the target ONT is relatively high, and indicates that the test optical signal with the target wavelength amplifies the optical signal with the offset wavelength, and it can be determined that the port with the target wavelength belongs to the first-stage optical splitter. Because the difference between the first power and the second power is smaller, it is indicated that the intensity of the optical signal with the offset wavelength received by the target ONT is lower, and it is indicated that the test optical signal with the target wavelength does not amplify the optical signal with the offset wavelength, and it can be determined that the port with the target wavelength belongs to the second-stage optical splitter.

In one possible implementation, the method further includes: acquiring third power when optical signals received by a target ONT comprise test optical signals with one wavelength, wherein the one wavelength is any one of multiple wavelengths, and the multiple wavelengths are wavelengths corresponding to different ports of each optical splitter of the ODN; determining a difference value between the third power corresponding to each wavelength and the power of the service optical signal; and if the difference between the third power corresponding to the first wavelength and the power of the service optical signal is smaller than the first value, determining that the port connected by the target ONT in the ODN is the port corresponding to the first wavelength.

In the solution shown in this application, the target ONT may obtain the third power when the optical signal received by the target ONT includes the test optical signal with one wavelength. The one wavelength is any one of a plurality of wavelengths corresponding to different ports of each optical splitter of the ODN. The target ONT may calculate a difference between the third power corresponding to each wavelength and the power of the service optical signal. And judging the difference between the third power corresponding to each wavelength and the power of the service optical signal and the first value, and if the difference between the third power corresponding to the first wavelength and the power of the service optical signal is smaller than the first value, determining that a port connected to the target ONT in the ODN is a port corresponding to the first wavelength. In this way, the port to which the ONT is connected in the ODN can be determined.

In a sixth aspect, an apparatus for determining a port to which an optical network terminal is connected is provided, the apparatus comprising a plurality of modules, and the plurality of modules implement the method for determining a port to which an optical network terminal is connected provided in the fifth aspect by executing instructions.

In a seventh aspect, a port identification device is provided, which includes a processor and a memory, wherein:

the memory having stored therein computer instructions; the processor executes the computer instructions to implement the method of the fifth aspect.

In an eighth aspect, there is provided a computer readable storage medium storing computer instructions which, when executed by a port identification device, cause the port identification device to perform the method of the fifth aspect.

In a ninth aspect, the present application provides a computer program product comprising computer instructions which, when executed by a port identification device, cause the port identification device to perform the method of the fifth aspect described above.

Drawings

Fig. 1 is a schematic diagram of an optical network terminal according to an exemplary embodiment of the present application;

FIG. 2 is a schematic diagram of the transmission of a traffic optical signal and a test optical signal provided by an exemplary embodiment of the present application;

fig. 3 is a schematic structural diagram of an optical network terminal according to an exemplary embodiment of the present application;

fig. 4 is a schematic structural diagram of an optical network terminal according to an exemplary embodiment of the present application;

fig. 5 is a schematic structural diagram of an optical network terminal according to an exemplary embodiment of the present application;

fig. 6 is a schematic structural diagram of an optical network terminal according to an exemplary embodiment of the present application;

fig. 7 is a schematic structural diagram of an optical network terminal according to an exemplary embodiment of the present application;

fig. 8 is a schematic structural diagram of an optical network terminal according to an exemplary embodiment of the present application;

fig. 9 is a schematic structural diagram of an optical network terminal according to an exemplary embodiment of the present application;

fig. 10 is a schematic structural diagram of an optical network terminal according to an exemplary embodiment of the present application;

fig. 11 is a schematic power diagram of an optical signal received by an optical network terminal according to an exemplary embodiment of the present application;

fig. 12 is a schematic structural diagram of an optical network terminal according to an exemplary embodiment of the present application;

FIG. 13 is a schematic diagram of a tunable wavelength laser according to an exemplary embodiment of the present application;

FIG. 14 is a schematic diagram of a tunable wavelength laser according to an exemplary embodiment of the present application;

FIG. 15 is a schematic flow chart of outputting a test optical signal provided by an exemplary embodiment of the present application;

fig. 16 is a schematic diagram of a system for determining a topology of an optical access network according to an exemplary embodiment of the present application;

fig. 17 is a schematic diagram of an optical distribution network provided by an exemplary embodiment of the present application;

fig. 18 is a schematic flow chart illustrating a process for determining a port of an optical network termination connected to an optical distribution network according to an exemplary embodiment of the present application;

FIG. 19 is a schematic illustration of amplification of an optical signal at an offset wavelength provided by an exemplary embodiment of the present application;

FIG. 20 is a block diagram illustrating an exemplary embodiment of a device for determining port identification provided herein;

fig. 21 is a schematic structural diagram of an apparatus for determining a port to which an optical network terminal is connected according to an exemplary embodiment of the present application.

Description of the drawings

An optical fiber interface 1, a light receiving component 2;

a light emitting component 3, a first filter 4;

a second filter 5, a processor 6;

a first light receiving element 21, a second light receiving element 22;

a laser 10, a beam splitter 20;

a first optical modulator 30, a light combiner 40;

second optical modulator 50, ONT100;

a tunable wavelength laser 200, a wavelength division multiplexer 300;

coupler 400, ODN500.

Detailed Description

To make the objects, technical solutions and advantages of the present application more clear, the following detailed description of the embodiments of the present application will be made with reference to the accompanying drawings.

To facilitate an understanding of the embodiments of the present application, the following first introduces concepts of the terms involved:

stimulated Brillouin amplification effect (i.e., stimulated Brillouin scattering, SBS)): stimulated brillouin scattering originates from the interaction of the laser electric field with the acoustic field in molecules or solids, i.e. the interaction of photons with phonons, also called phonon scattering. Stimulated brillouin scattering refers to a nonlinear optical effect in which a strong incident laser field induces a strong acoustic wave field in a medium and is scattered by it.

The generation process of the stimulated brillouin scattering is as follows: under the action of the electric field of laser, the medium is changed in periodic density and dielectric constant through electrostriction effect to induce an acoustic wave field, so that a coherent scattering process is generated between incident laser and the acoustic wave field. When the strong pumping laser field is injected into the medium, the electrostrictive effect of the light wave field starts to act, so that the acoustic vibration (phonon) of some states in the medium is greatly enhanced, the enhanced acoustic wave field also enhances the scattering effect on the injected laser, and the acoustic wave field, the laser wave field and the scattered light wave field of the laser exist in the medium at the same time and are coupled with each other. When the intensity of the incident laser reaches the threshold value, the respective loss effects are compensated by the enhancement effect of the acoustic wave field and the scattered light wave field in the medium, and the stimulated amplification or oscillation effect (namely the stimulated Brillouin amplification effect) of the induced acoustic wave field and the Brillouin scattered light wave field is generated. The scattered light has characteristics of stimulated emission such as a small divergence angle and a narrow line width, and is called stimulated brillouin scattering. It should be noted here that the stimulated brillouin amplification effect only occurs between two optical signals with opposite transmission directions.

The reflection grating is used for reflecting the optical signals incident to the reflection grating, and each reflection grating reflects the optical signals with one wavelength.

In the embodiment of the present application, an ONT is provided, where the ONT includes an optical fiber interface 1, a light receiving module 2, a light emitting module 3, a first filter 4, and a second filter 5, and the first filter 4 may be a 45-degree filter. Be provided with first filter 4 between optical fiber interface 1 and the optical transmission subassembly 3, optical transmission subassembly 3 is located the transmission light path of first filter 4. The optical transmission module 3 is used for sending an uplink optical signal when the ONT sends data uplink. The first filter 4 is used for transmitting the uplink optical signal emitted by the optical transmitting component 3 to the optical fiber interface 1.

The optical receiving component 2 can be matched with the first filter 4 and the second filter 5 to receive the test optical signal and the service optical signal (that is, the downlink service optical signal in the direction from the OLT to the ONT, and the service optical signal mentioned later is a downlink service optical signal), and the wavelength of the test optical signal is different from the wavelength of the service optical signal. The test optical signal is used to determine the port to which the ONT is connected in the ODN and the level of the optical splitter to which the port to which the ONT is connected in the ODN belongs. Thus, the reception of the test optical signal and the downstream service optical signal can be realized by one ONT.

In one possible implementation, as shown in fig. 1, the light receiving element 2 and the second filter 5 are located in the reflected light path of the first filter 4. The first filter 4 is used for transmitting the uplink optical signal emitted by the light emitting component 3 to the optical fiber interface 1, and can also be used for reflecting the test optical signal and the service optical signal received by the optical fiber interface 1 to the second filter 5. The second filter segment 5 may be used to transmit the test optical signal and the service optical signal to the light receiving module 2. In this way, the optical receiving module 2 can receive the test optical signal and the service optical signal. The optical receiving module 2 can detect the total power of the received test optical signal and the traffic optical signal. Wherein, the service optical signal is a downlink service optical signal. Thus, the reception of the test optical signal and the service optical signal can be realized by one ONT. Only the case where the first filter segment 4 is one filter segment is shown in fig. 1.

In one possible implementation, in fig. 1, the first filter 4 may be a tilted wave plate, such as the first filter 4 is a 45-degree tilted wave plate. First filter 4 can include a plurality of filters, and these a plurality of filters cooperate each other, will test light signal and business light signal reflection to second filter 5 to these a plurality of filters cooperate each other, make the pin direction of light receiving component 2 suitable, and then make the volume of ONT minimum. For example, the first filter 4 includes 2 filters (filter a and filter B), and both of the two filters are 45-degree filters, the filter a reflects the test optical signal and the service optical signal vertically downward in the horizontal plane, the filter B reflects the test optical signal and the service optical signal reflected by the filter a to the horizontal leftward direction, and then the light receiving assembly 2 is located on the left side in fig. 1.

In a possible implementation manner, in fig. 1, the second filter 5 includes a first surface and a second surface, the first surface is a surface on which the test optical signal and the service optical signal are incident to the second filter 5 for the first time, and the second surface is a back surface of the second filter 5 opposite to the first surface. The coating film of the first surface can transmit the service optical signal, the test optical signal and the intermediate optical signal, the coating film of the second surface can transmit the test optical signal and the service optical signal and block the intermediate optical signal, and the intermediate optical signal is an optical signal with a wavelength between the wavelength of the service optical signal and the wavelength of the test optical signal.

In a possible implementation manner, in fig. 1, the second filter 5 may be a band-pass filter, which is usually a fabry-perot type filter, and has a specific structure: the glass substrate is coated with a semitransparent metal layer, then coated with magnesium oxide layers, and further coated with a semitransparent metal layer, wherein the two metal layers form two parallel plates of the Fabry-Perot type optical filter. The window for transmitting the service optical signal is formed by using a Fabry-Perot type optical filter, and if the window for the test optical signal is added, the metal layer coating on the glass substrate can be changed to cover the wavelengths of the service optical signal and the test optical signal. Then, a stop band (i.e. the above-mentioned intermediate optical signal) is added between the service optical signal and the test optical signal by means of a coating, so as to achieve the separation of the wavelength of the service optical signal from the wavelength of the test optical signal.

For example, as shown in fig. 2, the original service optical signal has a wavelength range of λ 1 to λ 2, and after the metal layer coating film on the glass substrate is changed, the wavelength ranges of the cover service optical signal and the test optical signal are λ 1 to λ 3 (λ 2 < λ 3), and the wavelength ranges of the intermediate optical signal are λ 2 to λ 4, and λ 2 is not included. Fig. 2 shows that the wavelength of the test optical signal is greater than the wavelength of the service optical signal, but it is also possible that the wavelength of the test optical signal is less than the wavelength of the service optical signal.

In a possible implementation manner, in fig. 1, the second filter 5 may include two filters, the filter to which the service optical signal firstly enters may transmit the service optical signal, the test optical signal, and the intermediate optical signal, and the filter to which the service optical signal later enters may transmit the test optical signal and the service optical signal and block the intermediate optical signal, where the intermediate optical signal is an optical signal with a wavelength between the wavelength of the service optical signal and the wavelength of the test optical signal.

In one possible implementation, as shown in fig. 3, the light emitting assembly 3 is located in the reflected light path of the first filter 4. The light receiving component 2 and the second filter 5 are located on the transmission light path of the first filter 4. The first filter 4 is used for reflecting the uplink optical signal emitted by the light emitting component 3 to the optical fiber interface 1, and can also be used for transmitting the test optical signal and the service optical signal received by the optical fiber interface 1 to the second filter 5. The second filter segment 5 may be used to transmit the test optical signal and the service optical signal to the light receiving module 2. In this way, the optical receiving module 2 can receive the test optical signal and the service optical signal. The optical receiving module 2 may detect the total power of the received test optical signal and the traffic optical signal. Wherein, the service optical signal is a downlink service optical signal. Thus, the reception of the test optical signal and the service optical signal can be realized by one ONT.

It should be noted that for the ONTs shown in fig. 3, the first filter 4 and the second filter 5 can refer to the description in fig. 1, and the first filter 4 may also include a plurality of filters.

In one possible implementation, as shown in fig. 4, the light receiving module 2 includes a first light receiving module 21 and a second light receiving module 22, and the second filter 5 is located on the transmission light path of the first filter 4 and between the first filter 4 and the light emitting module 3. The first light receiving element 21 is located on the reflection light path of the first filter 4, and the second light receiving element 22 is located on the reflection light path of the second filter 5. The first filter 4 is configured to transmit the uplink optical signal emitted by the light emitting module 3 to the optical fiber interface 1, and further configured to reflect the test optical signal received by the optical fiber interface 1 to the first light receiving module 21. Thus, the first light receiving element 21 can receive the test light signal and detect the power of the received test light signal.

The first filter 4 is further configured to transmit the service optical signal received by the optical fiber interface 1 to the second filter 5. The second filter 5 is configured to reflect the service optical signal received by the optical fiber interface 1 to the second optical receiving component 22. In this way, the second optical receiving component 22 can receive the service optical signal and perform normal downlink service.

The second filter 5 may also be configured to transmit the uplink optical signal sent by the optical transmitting component 3 to the first filter 4, and the first filter 4 is configured to transmit the uplink optical signal to the optical fiber interface 1, so as to implement normal uplink service of the ONT.

In one possible implementation, as shown in fig. 5, the light receiving module 2 includes a first light receiving module 21 and a second light receiving module 22, and the second filter 5 is located on the transmission light path of the first filter 4 and between the first filter 4 and the light emitting module 3. The second light receiving element 22 is located on the reflection light path of the first filter 4, and the first light receiving element 21 is located on the reflection light path of the second filter 5. The first filter 4 is configured to transmit the uplink optical signal emitted by the optical transmitter module 3 to the optical fiber interface 1, and further configured to reflect the service optical signal received by the optical fiber interface 1 to the second optical receiver module 22. Thus, the second optical receiving module 22 can receive the service optical signal and perform normal downlink service.

The first filter 4 is further configured to transmit the test light signal received by the optical fiber interface 1 to the second filter 5. The second filter 5 is used for reflecting the test light signal received by the optical fiber interface 1 to the first light receiving component 21. Thus, the first light receiving element 21 can receive the test light signal and detect the power of the received test light signal.

The second filter 5 may also be configured to transmit the uplink optical signal sent by the optical transmitting component 3 to the first filter 4, so as to implement normal uplink service of the ONT.

In one possible implementation, as shown in fig. 6, the light receiving module 2 includes a first light receiving module 21 and a second light receiving module 22, and the second filter 5 is located on the transmission light path of the first filter 4 and between the first filter 4 and the second light receiving module 22. The first light receiving component 21 is located on the reflection light path of the second filter 5, and the light emitting component 3 is located on the reflection light path of the first filter 4. The first filter 4 is configured to transmit an uplink optical signal transmitted by the optical transmit module 3 to the optical fiber interface 1 through reflection, so as to implement normal uplink service of the ONT. The first filter 4 is further configured to transmit the test optical signal and the service optical signal received by the optical fiber interface 1 to the second filter 5.

The second filter 5 is configured to transmit the service optical signal received by the optical fiber interface 1 to the second optical receiving component 22. The second filter 5 is further configured to reflect the test light signal received by the optical fiber interface 1 to the first light receiving component 21. Thus, the second optical receiving module 22 can receive the service optical signal and perform normal downlink service, and the first optical receiving module 21 can receive the test optical signal and detect the power of the received test optical signal.

In one possible implementation, as shown in fig. 7, the light receiving module 2 includes a first light receiving module 21 and a second light receiving module 22, and the second filter 5 is located on the transmission light path of the first filter 4 and between the first filter 4 and the first light receiving module 21. The second light receiving component 22 is located on the reflection light path of the second filter 5, and the light emitting component 3 is located on the reflection light path of the first filter 4. The first filter 4 is configured to transmit an uplink optical signal transmitted by the optical transmitting component 3 to the optical fiber interface 1 through reflection, so as to implement normal uplink service of the ONT. The first filter 4 is further configured to transmit the test optical signal and the service optical signal received by the optical fiber interface 1 to the second filter 5.

The second filter 5 is configured to reflect the service optical signal received by the optical fiber interface 1 to the second optical receiving component 22. The second filter 5 is also used for transmitting the test light signal received by the optical fiber interface 1 to the first light receiving component 21. Thus, the second optical receiver module 22 can receive the service optical signal and perform normal downlink service, and the first optical receiver module 21 can receive the test optical signal and detect the power of the received test optical signal.

In one possible implementation, as shown in fig. 8, the light receiving module 2 includes a first light receiving module 21 and a second light receiving module 22, and the second filter 5 is located on the transmission light path of the first filter 4 and between the first filter 4 and the first light receiving module 21. The second light receiving component 22 is located on the reflection light path of the first filter 4, and the light emitting component 3 is located on the reflection light path of the second filter 5. The second filter 5 is configured to reflect the uplink optical signal transmitted by the optical transmitter module 3 to the first filter 4, and the first filter 4 is configured to transmit the uplink optical signal transmitted by the optical transmitter module 3 to the optical fiber interface 1, so as to implement normal uplink service of the ONT. The first filter 4 is further configured to reflect the service optical signal received by the optical fiber interface 1 to the second optical receiving component 22, and the first filter 4 is further configured to transmit the test optical signal received by the optical fiber interface 1 to the second filter 5.

The second filter 5 is also used for transmitting the test light signal received by the optical fiber interface 1 to the first light receiving component 21.

Thus, the second optical receiver module 22 can receive the service optical signal and perform normal downlink service, and the first optical receiver module 21 can receive the test optical signal and detect the power of the received test optical signal.

In one possible implementation, as shown in fig. 9, the light receiving module 2 includes a first light receiving module 21 and a second light receiving module 22, and the second filter 5 is located on the transmission light path of the first filter 4 and between the first filter 4 and the second light receiving module 22. The first light receiving component 21 is located on the reflection light path of the first filter 4, and the light emitting component 3 is located on the reflection light path of the second filter 5. The second filter 5 is configured to reflect the uplink optical signal transmitted by the optical transmitter module 3 to the first filter 4, and the first filter 4 is configured to transmit the uplink optical signal transmitted by the optical transmitter module 3 to the optical fiber interface 1, so as to implement normal uplink service of the ONT. The first filter 4 is further configured to reflect the test optical signal received by the optical fiber interface 1 to the first optical receiving component 21, and the first filter 4 is further configured to transmit the service optical signal received by the optical fiber interface 1 to the second filter 5.

The second filter 5 is also used for transmitting the service optical signal received by the optical fiber interface 1 to the second optical receiving component 22.

Thus, the second optical receiving module 22 can receive the service optical signal and perform normal downlink service, and the first optical receiving module 21 can receive the test optical signal and detect the power of the received test optical signal.

In a possible implementation manner, in a case that the light receiving module 2 includes the first light receiving module 21 and the second light receiving module 22, a zero-degree filter may also be added before the first light receiving module 21 and the second light receiving module 22, where the zero-degree filter added before the first light receiving module 21 is used to filter out other optical signals except for the test optical signal, and the zero-degree filter added before the second light receiving module 22 is used to filter out other optical signals except for the downstream service optical signal.

In a possible implementation manner, corresponding to the ONT shown in fig. 1, as shown in fig. 10, the ONT further includes a processor 6, and the processor 6 is electrically connected to the light receiving module 2. In order to determine the ports of the ONTs connected in the ODN, each port of the optical splitter in the ODN is provided with a reflective grating, and the wavelength of the optical signal that can be reflected by the reflective grating provided at each port is different. Test optical signals with various wavelengths are input into the ODN, and the various wavelengths are composed of the wavelengths of the optical signals capable of being reflected by the reflection grating arranged at each port of the optical splitter of the ODN. The optical receiving module 2 of the ONT may detect the total power of the test optical signal and the service optical signal received each time.

The processor 6 may obtain a pre-stored power of the service optical signal, which may be the power of the service optical signal detected by the optical receiving element 2 when no test optical signal is input to the ODN. The processor 6 may take a difference between each total power and the power of the traffic optical signal to obtain a first difference corresponding to each total power. The processor 6 may then determine the magnitude of the first difference and the first value corresponding to each total power, and if the first difference corresponding to a certain total power is smaller than the first value, may determine the first wavelength of the received test optical signal to which the certain total power belongs. The processor 6 sets the port where the ONT is connected in the ODN as the port corresponding to the first wavelength. It should be noted here that the port corresponding to the first wavelength is a port where the reflection grating of the first wavelength is located, and the port belongs to the optical splitter.

In a possible implementation manner, as shown in fig. 10, the ONT further includes a processor 6 corresponding to the ONT shown in fig. 1, and the processor 6 is electrically connected to the light receiving module 2. In order to determine the ports of the ONTs connected in the ODN, each port of the optical splitter in the ODN is provided with a reflective grating, and the wavelength of the optical signal that can be reflected by the reflective grating provided at each port is different. Test optical signals with various wavelengths are input into the ODN, and the various wavelengths are composed of the wavelengths of the optical signals capable of being reflected by the reflection grating arranged at each port of the optical splitter of the ODN. The optical receiving module 2 of the ONT may detect the total power of the test optical signal and the service optical signal received each time.

The processor 6 may determine a maximum value (i.e., a maximum total power) of the detected plurality of total powers, and then calculate a second difference value between the maximum value and each detected total power, to obtain a second difference value corresponding to each total power. The processor may determine a magnitude of a second difference and a second value for each total power. The processor 6 determines the first wavelength of the received test light signal when the second difference corresponding to the total power is greater than the second value. The processor 6 may determine that the port to which the ONT is connected in the ODN is the port corresponding to the first wavelength. It should be noted here that the port corresponding to the first wavelength is a port where the reflection grating of the first wavelength is located, and the port belongs to the optical splitter.

It should be noted that, because the port of the reflection grating is disposed in the ODN and reflects the optical signal with the wavelength corresponding to the reflection grating, the test optical signal with the wavelength corresponding to the reflection grating is reflected back after being incident on the reflection grating, and does not reach the ONT, so that the ONT can only detect the power of the service optical signal, and thus it can be determined that the ONT is connected to the port where the reflection grating is located in the ONT. For example, as shown in fig. 11, the plurality of wavelengths are 8 wavelengths (λ 1 to λ 8), and a first difference between the total power detected by the ONT and the power of the service optical signal at λ 1 and λ 4 is smaller than a first value, it can be determined that the ports to which the ONT is connected in the ODN are the ports corresponding to λ 1 and λ 4, respectively.

It should be further noted that, in the ODN, the reflection gratings disposed at different ports of the first optical splitter reflect the test optical signals with different wavelengths, the reflection gratings disposed at different ports of the second optical splitter reflect the test optical signals with different wavelengths, and the wavelengths corresponding to the different ports of the first optical splitter are the same as or different from the wavelengths corresponding to the different ports of each optical splitter of the second optical splitter. For example, the first-stage optical splitter includes 8 ports, and the 8 ports correspond to wavelengths λ 1 to λ 8, and each optical splitter of the second-stage optical splitter includes 8 ports, and the 8 ports correspond to wavelengths λ 1 to λ 8. Or, the first-stage optical splitter includes 8 ports, the wavelengths corresponding to the 8 ports are λ 1 to λ 8, each optical splitter of the second-stage optical splitter includes 8 ports, and the wavelengths corresponding to the 8 ports are λ 9 to λ 16. Under the condition that the wavelengths corresponding to the different ports of the first-stage optical splitter are the same as the wavelengths corresponding to the different ports of each of the second-stage optical splitters, the first wavelength determined by the processor 6 only includes one wavelength, which may indicate that the port connected by the ONT in the first-stage optical splitter in the ODN is the port corresponding to the wavelength, and the port connected in the second-stage optical splitter is also the port corresponding to the wavelength.

It should be noted that, in fig. 4 to 10, the first filter 4 in each ONT may be composed of a plurality of filters, and the plurality of filters cooperate with each other to satisfy the function of the first filter 4, and to minimize the volume of the ONT. The second filter 5 may consist of a plurality of filters in each kind of ONT, which cooperate with each other to minimize the volume of the ONT in addition to fulfilling the function of the second filter 5.

It should be further noted that, in the embodiment of the present application, the first filter 4 and the second filter 5 both transmit optical signals in the horizontal direction during transmission, and during implementation, the optical signals may also be transmitted along other directions by adjusting the arrangement of the first filter 4 and the second filter 5.

In a possible implementation manner, in the foregoing process, when the ONT is connected to a port corresponding to a first wavelength in the ODN, and when the wavelengths corresponding to different ports of the first-stage optical splitter are the same as the wavelengths corresponding to different ports of each second-stage optical splitter (for example, the first wavelength includes λ 1 and λ 4, the ports connected by the ONT in the ODN are the ports corresponding to λ 1 and λ 4, respectively, but it cannot be determined whether the port corresponding to λ 1 belongs to the first-stage optical splitter or the second-stage optical splitter of the ODN, and likewise, cannot be determined whether the port corresponding to λ 4 belongs to the first-stage optical splitter or the second-stage optical splitter of the ODN), the present embodiment further provides a level for determining the optical splitter to which the port corresponding to the first wavelength connected by the ONT in the ODN belongs, and processes as:

the processor 6 may further obtain powers detected by the optical receiving component 2 when the received test optical signal includes an optical signal of an offset wavelength, i.e., a first total power and a second total power. When the detected power is the first total power, the optical signal with the offset wavelength included in the test optical signal received by the optical receiving component 2 is an optical signal when the test optical signal with the target wavelength and the optical signal with the offset wavelength are input to the ODN together, and when the detected power is the second total power, the optical signal with the offset wavelength included in the test optical signal received by the optical receiving component 2 is an optical signal when the test optical signal with the target wavelength is not input to the ODN. Specifically, the test optical signal with the target wavelength may be amplified at a first port of a first-stage optical splitter of the ODN, while the optical signal with the offset wavelength is not amplified at a second port of a second-stage optical splitter of the ODN, and reflection gratings disposed at the first port and the second port reflect the test optical signal with the target wavelength. The target wavelength is one of the above-described first wavelengths, for example, the first wavelength includes λ 1 and λ 4, and the target wavelength is λ 1 or λ 4.

The processor 6 may determine a third difference between the first total power and the second total power, and determine a magnitude of the third difference from the target threshold. If the third difference is greater than or equal to the target threshold, it may be determined that the port corresponding to the target wavelength belongs to the first-stage optical splitter of the ODN, and it may be determined that the port corresponding to a wavelength other than the target wavelength in the first wavelength belongs to the second-stage optical splitter of the ODN. If the third difference is smaller than the target threshold, it may be determined that the port corresponding to the target wavelength belongs to the second-stage optical splitter of the ODN, and it may be determined that the port corresponding to the wavelength other than the target wavelength in the first wavelength belongs to the first-stage optical splitter of the ODN.

The optical signal with the offset wavelength is amplified after the test optical signal with the target wavelength is transmitted to the first port of the first-stage optical splitter of the ODN, and the power of the reflected second test optical signal is greater than or equal to the threshold value for generating the brillouin amplification effect. After the test optical signal with the target wavelength is transmitted to the second port of the second-stage optical splitter of the ODN, although the test optical signal with the target wavelength is reflected by the reflection grating arranged on the second port, the test optical signal with the target wavelength is attenuated by the first-stage optical splitter and the second-stage optical splitter, the intensity of the test optical signal with the target wavelength after being reflected by the reflection grating arranged on the second port is relatively low, the power of the reflected second test optical signal is less than the threshold value for generating the brillouin amplification effect, and the optical signal with the offset wavelength cannot be amplified, so that the intensity of the optical signal with the offset wavelength transmitted to the ONT is relatively low, and the first total power is relatively low. The second total power represents the total power of the service optical signal and the test optical signal detected by the optical receiving component 2 when the test optical signal with the target wavelength and the optical signal with the offset wavelength are not input to the ODN together, that is, the total power of the service optical signal and the test optical signal detected by the optical receiving component 2 when only the optical signal with the offset wavelength is input to the ODN. Therefore, when the difference between the first total power and the second total power is relatively large, it is described that the port corresponding to the target wavelength connected to the ONT belongs to the first-stage optical splitter of the ODN, and when the difference between the first total power and the second total power is relatively small, it is described that the port corresponding to the target wavelength connected to the ONT belongs to the second-stage optical splitter of the ODN.

In a possible implementation manner, as shown in fig. 12, corresponding to the ONT of fig. 4, the ONT further includes a processor 6, and the processor 6 is electrically connected to the light receiving module 2, and of course, the processor 6 is electrically connected to the first light receiving module 21. In order to determine the ports to which the ONTs are connected in the ODN, each port of the optical splitter in the ODN is provided with a reflective grating, and the wavelength corresponding to the reflective grating provided in each port is different (that is, the wavelength of the optical signal that can be reflected by each reflective grating is different). Test optical signals with various wavelengths are input into the ODN, and the various wavelengths consist of wavelengths corresponding to reflection gratings arranged at each port of an optical splitter of the ODN. The first optical receiving component 21 of the ONT may detect the power of the test optical signal received each time.

The processor 6 may determine the maximum value among the plurality of powers of the test optical signal received by the first optical receiving module 21, and then calculate a fourth difference value of the maximum power and each power of the test optical signal received by the first optical receiving module 21. The processor determines the magnitude of the fourth difference value and the second value corresponding to each power, and determines the first wavelength of the test optical signal received by the first optical receiving element 21 corresponding to a certain power when the fourth difference value corresponding to the certain power is greater than the second value. The processor 6 may then determine that the port to which the ONT is connected in the ODN is the port corresponding to the first wavelength. The port corresponding to the first wavelength is a port in the ODN, where a reflection grating for reflecting the test optical signal of the first wavelength is disposed.

It should be noted here that the reason why the ports where the ONTs are connected in the ODN can be determined here is: since the ONT cannot receive the test optical signal of which wavelength, it is described that the ONT is connected to a port provided with a reflection grating for reflecting the optical signal of the wavelength, and the port connected to the ONT in the ODN can be determined by using this principle.

In a possible implementation manner, in a case that the optical receiving component 2 includes the first optical receiving component 21 and the second optical receiving component 22, the ONT connects a port corresponding to the first wavelength in the OND, and in a case that the wavelength corresponding to the different port of the first-stage optical splitter is the same as the wavelength corresponding to the different port of each optical splitter of the second-stage optical splitter, the embodiment of the present application further provides determining the level of the optical splitter to which the port corresponding to the first wavelength connected by the ONT in the ODN belongs, and the processing is:

the processor 6 may also obtain the powers, i.e., the first power and the second power, detected by the first optical receiving element 21 when the received test optical signal includes an optical signal of an offset wavelength. When the detected power is the first power, the optical signal when the test optical signal received by the first optical receiving element 21 includes the optical signal with the offset wavelength and the test optical signal with the target wavelength, which are input to the ODN together; when the detected power is the second power, the test optical signal received by the first optical receiving element 21 includes an optical signal of an offset wavelength when the test optical signal of the target wavelength is not input to the ODN together with the optical signal. Specifically, the test optical signal with the target wavelength may amplify the optical signal with the offset wavelength at a first port of a first-stage optical splitter of the ODN, but not amplify the optical signal with the offset wavelength at a second port of a second-stage optical splitter of the ODN, and reflection gratings disposed at the first port and the second port reflect the test optical signal with the target wavelength. The target wavelength is one of the wavelengths included in the first wavelength.

The processor 6 may determine a fifth difference between the first power and the second power, and determine the magnitude of the fifth difference and the target threshold. If the fifth difference is greater than or equal to the target threshold, it may be determined that the port corresponding to the target wavelength belongs to the first-stage optical splitter of the ODN, and it may be determined that the port corresponding to a wavelength other than the target wavelength in the first wavelength belongs to the second-stage optical splitter of the ODN. If the fifth difference is smaller than the target threshold, it may be determined that the port corresponding to the target wavelength belongs to the second-stage optical splitter of the ODN, and it may be determined that the port corresponding to the wavelength other than the target wavelength in the first wavelength belongs to the first-stage optical splitter of the ODN. The principles herein are the same as those described in the foregoing and are not described in further detail herein.

Thus, through the ONT, not only the port connected by the ONT in the ODN can be determined, but also the level of the optical splitter to which the port connected by the ONT in the ODN belongs can be determined.

In the embodiment of the present application, as shown in fig. 13, a device for outputting a test optical signal, that is, a tunable wavelength laser is further provided. The tunable laser includes a laser 10, a beam splitter 20, a first optical modulator 30, and a light combiner 40, where the beam splitter 20 includes a first light outlet and a second light outlet. The laser 10 can output test optical signals with various wavelengths, which are wavelengths of optical signals that can be reflected by the reflection grating disposed at the port of the beam splitter in the ODN. The beam splitter 20 may be located between the laser 10 and the first optical modulator 30, and the beam splitter 20 is located at the light outlet of the laser 10, and the first optical modulator 30 is located at the first light outlet of the beam splitter 20. The light combiner 40 is located at the light outlet of the first light modulator 30 and the second light outlet of the beam splitter 20.

The beam splitter 20 is configured to split the test optical signal with the target wavelength output by the laser 10 into a first test optical signal and a second test optical signal, and output the first test optical signal and the second test optical signal through the first light outlet and the second light outlet, respectively, where the first test optical signal is input to the first optical modulator 30. The first optical modulator 30 may shift the wavelength of the first test optical signal by a target value to obtain an optical signal of a shifted wavelength. And a second test optical signal output by the second light outlet enters the optical combiner.

The light combiner 40 combines the second test light signal and the light signal with the offset wavelength to obtain a light signal, and outputs the light signal. In addition, when the first optical modulator 30 turns off the output, the optical combiner 40 may output only the second test optical signal, and when the second test optical signal is not present, the optical combiner 40 may output only the optical signal with the shifted wavelength.

Under the condition that the optical combiner 40 outputs the second test optical signal and the optical signal with the offset wavelength, after the second test optical signal and the optical signal with the offset wavelength enter the ODN, a port corresponding to the target wavelength of the first-stage optical splitter in the OND reflects the second test optical signal, and the power of the reflected second test optical signal is greater than or equal to the threshold value for generating the brillouin amplification effect, so that the optical signal with the offset wavelength can be amplified. The port corresponding to the target wavelength of the second-stage optical splitter in the ODN performs reflection processing on the second test optical signal, and the second test optical signal after reflection processing has low intensity due to attenuation of the first-stage optical splitter and the second-stage optical splitter, and the power of the second test optical signal is smaller than the threshold value for generating the brillouin amplification effect, so that the optical signal with the offset wavelength cannot be amplified. In this way, it can be used to distinguish whether the port to which the ONT is connected in the ODN belongs to the first stage optical splitter or the second stage optical splitter.

In a possible implementation manner, as shown in fig. 14, the tunable wavelength laser further includes a second optical modulator 50, where the second optical modulator 50 is located between the second light outlet of the beam splitter 20 and the light combiner 40, and the second optical modulator 50 may be configured to adjust the power of the second test optical signal entering the second optical modulator 50, so that the power of the second test optical signal satisfies that the optical signal with the offset wavelength is amplified at a port corresponding to the target wavelength of the first-stage optical splitter of the ODN, and the optical signal with the offset wavelength is not amplified at a port corresponding to the target wavelength of the optical splitter other than the first optical splitter in the ODN (the principle is described above).

In one possible implementation, the first optical modulator 30 may be an electro-optic modulator and the second optical modulator 50 may be a semiconductor modulator.

In the embodiment of the present application, a method for outputting a test optical signal in a tunable laser corresponding to the tunable laser shown in fig. 13 is also provided. The execution flow of the method is shown in fig. 15:

step 1501, the tunable wavelength laser outputs a test optical signal with a target wavelength, where the target wavelength is a wavelength of any one of multiple test optical signals that can be output by the tunable wavelength laser. The target wavelength is one of the wavelengths included in the first wavelength.

Step 1502, the tunable wavelength laser splits the test optical signal with the target wavelength into two optical signals, where the two optical signals include a first test optical signal and a second test optical signal.

In this implementation, the tunable wavelength laser may split a test optical signal at a target wavelength into two optical signals, which may include a first test optical signal and a second test optical signal. The wavelengths of the first test optical signal and the second test optical signal are both target wavelengths.

In step 1503, the tunable laser performs wavelength shift processing on the first test optical signal to obtain an optical signal with shifted wavelength.

In this embodiment, the tunable laser may shift the target wavelength of the first test optical signal by a target value, so as to obtain an optical signal with a shifted wavelength. For example, where the bandwidth of the reflective grating is less than 20GHz, the target value may be 10GHz, such that the offset wavelength is the sum of the target wavelength and the wavelength corresponding to 10GHz, or the offset wavelength is the difference between the target wavelength and the wavelength corresponding to 10 GHz.

Step 1504, the tunable wavelength laser synthesizes a second test optical signal and an optical signal with the offset wavelength, and outputs the synthesized optical signal, wherein the power of the second test optical signal after being reflected at a port corresponding to the target wavelength of the first-stage optical splitter of the ODN is greater than or equal to the threshold value for generating the brillouin amplification effect, and the power of the second test optical signal after being reflected at a port corresponding to the target wavelength of the second-stage optical splitter of the ODN is less than the threshold value for generating the brillouin amplification effect.

In this embodiment, the tunable wavelength laser may output the second test optical signal and/or the optical signal with the offset wavelength, i.e. to the ODN.

Here, when the second test optical signal and the optical signal with the offset wavelength coexist, the second test optical signal and the optical signal with the offset wavelength are combined into one optical signal to be output, the port corresponding to the target wavelength of the first-stage optical splitter in the OND performs reflection processing on the second test optical signal, the power of the reflected second test optical signal is greater than or equal to the threshold value for generating the brillouin amplification effect, and the optical signal with the offset wavelength can be amplified. The port corresponding to the target wavelength of the second-stage optical splitter in the ODN reflects the second test optical signal, and the reflected second test optical signal is low in intensity due to the attenuation of the first-stage optical splitter and the second-stage optical splitter, and the power of the reflected second test optical signal is smaller than the threshold value for generating the Brillouin amplification effect, so that the optical signal with the offset wavelength cannot be amplified. In this way, if the port to which the ONT is connected is the port corresponding to the target wavelength of the first-stage optical splitter, the power of the test optical signal detected by the ONT is the power of the amplified optical signal with the offset wavelength, and the detected power is relatively high.

In the flow of fig. 15, in order to make the power of the second test optical signal satisfy the condition that the optical signal with the offset wavelength is amplified at the port corresponding to the target wavelength of the first-stage optical splitter of the ODN, the optical signal with the offset wavelength is not amplified at the port corresponding to the target wavelength of the optical splitter other than the first optical splitter in the ODN. The tunable wavelength laser can adjust the power of the second test optical signal, so that the tunable wavelength laser can synthesize the second test optical signal after power adjustment and the optical signal with offset wavelength into one optical signal, and output the optical signal to the ODN.

In a possible implementation manner, before step 1501, the current OLT knows that a wavelength corresponding to a port connected by a target ONT (any ONT) in the ODN is a target wavelength, and at this time, the OLT may send a wavelength output instruction to the tunable wavelength laser, where the wavelength output instruction is used to instruct the tunable wavelength laser to output a test optical signal of the target wavelength. The tunable wavelength laser may then output the test optical signal at the target wavelength, and in step 1504, the tunable wavelength laser may output the second test optical signal and the optical signal at the offset wavelength to the ODN. Thus, in fig. 1, the optical receiving module 2 of the ONT detects the first total power. In fig. 4, the first optical receiving component 21 of the ONT detects the first power.

In addition, after the tunable wavelength laser outputs the second test optical signal and the optical signal with the offset wavelength, the tunable wavelength laser may further receive a turn-off instruction of the second test optical signal. The tunable wavelength laser may turn off the output of the second test optical signal and output only the optical signal at the offset wavelength to the ODN. Thus, in fig. 1, the optical receiving module 2 of the ONT detects the second total power. In fig. 4, the first optical receiving component 21 of the ONT detects the second power.

In this way, the ONT may determine, based on the first total power and the second total power, that a port corresponding to a target wavelength to which the target ONT is connected in the ODN belongs to the first-stage optical splitter or the second-stage optical splitter. Alternatively, the ONT may determine, based on the first power and the second power, that a port corresponding to a target wavelength connected by the target ONT in the ODN belongs to the first-stage optical splitter or the second-stage optical splitter (this process is described in the foregoing and is not described here again).

In a possible implementation manner, the processing of detecting the port to which the target ONT is connected in the ODN is:

the adjustable wavelength laser receives a closing instruction of an output port where an optical signal with offset wavelength is located, the closing instruction is sent by the OLT, the output of the output port where the optical signal with offset wavelength is located is closed, and various testing optical signals are output according to a preset wavelength sequence of the testing optical signals, wherein the various testing optical signals are used for determining ports, connected in the ODN, of a target ONT.

In this embodiment, the OLT may send a turn-off command for the optical signal with the offset wavelength and a command for sending out various test optical signals to the tunable wavelength laser. The tunable wavelength laser may receive both commands and then turn off the output of the shifted wavelength optical signal (which may specifically be the output of the first optical modulator 30).

The tunable laser may emit a plurality of test optical signals according to a preset wavelength sequence (which may be issued to the tunable laser by an instruction from the OLT or may be preconfigured in the tunable laser). In this way, the tunable wavelength laser can output only the second test optical signal of each test optical signal. In fig. 1, the optical receiving component 2 of the ONT detects the total power of the second test optical signal and the service optical signal, and in fig. 4, the first optical receiving component 21 of the ONT detects the power of the second test optical signal. Thus, the ONT may determine the port to which the ONT is connected in the ODN based on the total power or the power (this process is described in the foregoing and is not described here again).

In an embodiment of the present application, there is further provided a system for determining a topology of an optical access network, the system including an ONT100, a tunable wavelength laser 200, and a wavelength division multiplexer 300 or a coupler 400; specifically, the tunable wavelength laser 200 is shown in fig. 13 and 14, and the ONT100 is shown in any one of fig. 1, 3 to 10. The wavelength division multiplexer 300 and the coupler 400 may be configured to combine the service optical signal and the test optical signal into a single optical signal, where the service optical signal refers to a downstream service optical signal, i.e., a service optical signal from the OLT to the ONT 100.

In one possible implementation, as shown in fig. 16, the system for determining the topology of the optical access network further includes an ODN500, where the ODN500 is connected to the wavelength division multiplexer 300 or the coupler 400, and the ODN500 is connected to the ONTs 100.

The ODN500 includes a first-stage optical splitter and a second-stage optical splitter, each port of the first-stage optical splitter and the second-stage optical splitter is provided with a reflection grating, and the wavelength of an optical signal that can be reflected by the reflection grating is different from the wavelength of a service optical signal.

Specifically, each port of the first-stage optical splitter and each port of the second-stage optical splitter are provided with a reflection grating with the same wavelength, and for any one of the first-stage optical splitter and the second-stage optical splitter, each port of the optical splitter adopts a reflection grating with different wavelengths. For example, as shown in fig. 17, the ODN500 includes a first-stage optical splitter and a second-stage optical splitter, the first-stage optical splitter is a 1 × 8 optical splitter, the second-stage optical splitter includes 8 1 × 8 optical splitters, wavelengths of optical signals that can be reflected by reflection gratings respectively disposed at different ports of the first-stage optical splitter are λ 1 to λ 8, and wavelengths of optical signals that can be reflected by reflection gratings respectively disposed at different ports of any one of the second-stage optical splitters are λ 1 to λ 8. In fig. 17 the second stage splitter shows only one splitter.

Or, each port of the first-stage optical splitter and each port of each optical splitter of the second-stage optical splitter are provided with reflection gratings with different wavelengths, and each port of each optical splitter of the second-stage optical splitter is provided with a reflection grating with the same wavelength. For example, the first-stage optical splitter is a 1 × 8 optical splitter, the second-stage optical splitter includes 8 optical splitters 1 × 8, the wavelengths of the optical signals that can be reflected by the reflection gratings respectively disposed at different ports of the first-stage optical splitter are λ 1 to λ 8, and the wavelengths of the optical signals that can be reflected by the reflection gratings respectively disposed at different ports of any one of the second-stage optical splitters are λ 9 to λ 16.

In one possible implementation, the tunable wavelength laser 200 may be disposed in the OLT.

In this embodiment, the tunable wavelength laser 200 and the ONT100 in the system for determining the topology of the optical access network may cooperate to determine the port of the ONT100 connected in the ODN500 (see the flow shown in fig. 15 and the flow shown in fig. 18), i.e. determine the topology of the optical access network.

In this embodiment of the present application, a method for determining a port to which an ONT is connected is further provided, where an execution main body of the method may be a port identification device, and the port identification device may be an ONT, may also be an OLT, and may also be other terminals or servers, and the like, which is not limited in this embodiment of the present application, and the following description takes the port identification device as the ONT as an example:

as shown in fig. 18, the execution flow of the method may be as follows:

step 1801, obtaining a difference between a first power and a second power corresponding to a target ONT, where a wavelength corresponding to a port of the target ONT connected in an optical distribution network ODN is a target wavelength; the offset wavelength is a wavelength obtained by offsetting the target wavelength by the target value, and the first power and the second power are powers when the optical signal received by the target ONT comprises the optical signal with the offset wavelength; when the optical signal corresponds to the first power, the optical signal input to the optical distribution network ODN together with the optical signal with the offset wavelength includes a test optical signal with a target wavelength; and when the second power is corresponded, the optical signal input into the ODN includes an optical signal with the offset wavelength and does not include a test optical signal with the target wavelength, the power of the test optical signal with the target wavelength after being reflected at a port corresponding to the target wavelength of the first-stage optical splitter of the ODN is greater than or equal to the threshold value for generating the brillouin amplification effect, and the power of the test optical signal with the target wavelength after being reflected at a port corresponding to the target wavelength of the second-stage optical splitter of the ODN is smaller than the threshold value for generating the brillouin amplification effect.

The target ONT is any ONT, a wavelength corresponding to a port of the target ONT connected in the optical distribution network ODN is a target wavelength (that is, a wavelength included in the aforementioned first wavelength), and the offset wavelength is a wavelength obtained by offsetting a target value from the target wavelength.

In this embodiment, the target ONT may obtain a first power and a second power, where the first power is a power when an optical signal received by the target ONT includes an optical signal with an offset wavelength, and when the target ONT detects the first power, an optical signal input to the ODN by the tunable wavelength laser is a test optical signal with the target wavelength and an optical signal with the offset wavelength. Thus, the optical signals input into the ODN include a test optical signal at a target wavelength and an optical signal at an offset wavelength.

The second power is a power when the optical signal received by the target ONT includes an optical signal with an offset wavelength, and when the target ONT detects the second power, the optical signal input into the ODN by the tunable wavelength laser is the optical signal with the offset wavelength, so that the optical signal input into the ODN is the optical signal with the offset wavelength.

The targeted ONT may determine a difference between the first power and the second power.

Here, the test optical signal with the target wavelength is obtained by amplifying the optical signal with the offset wavelength at the port corresponding to the target wavelength of the first stage optical splitter of the ODN, and is not obtained by amplifying the optical signal with the offset wavelength at the port corresponding to the target wavelength of the second stage optical splitter of the ODN.

It should be noted here that the OLT may notify the ONT of the wavelength of the optical signal sent out this time, and notify whether a test optical signal with the target wavelength is input this time. In this way, the ONT may know which detected power is the first power and which detected power is the second power, and subsequently, may further determine whether a port of a target wavelength connected by the target ONT in the ODN belongs to the first-stage optical splitter or the second-stage optical splitter.

Step 1802, if the difference is greater than or equal to the target threshold, determining that a port corresponding to the target wavelength belongs to a first-stage optical splitter of the ODN; and if the difference value is smaller than the target threshold value, determining that the port corresponding to the target wavelength belongs to the second-stage optical splitter of the ODN.

In this embodiment, the target ONT may determine a difference between the first power and the second power and a target threshold. If the difference between the first power and the second power is greater than or equal to the target threshold, the target ONT may determine that a port corresponding to the target wavelength belongs to the first stage optical splitter of the ODN, and may determine that a port corresponding to another wavelength other than the target wavelength in the first wavelength belongs to the second stage optical splitter of the ODN. If the difference is smaller than the target threshold, the target ONT may determine that the port corresponding to the target wavelength belongs to the second-stage optical splitter of the ODN, and may determine that the port corresponding to another wavelength other than the target wavelength in the first wavelength belongs to the first-stage optical splitter of the ODN. The reason is that the difference between the first power and the second power is relatively large, which indicates that the intensity of the optical signal with the offset wavelength received by the target ONT is relatively high, and indicates that the test optical signal with the target wavelength amplifies the optical signal with the offset wavelength, and it can be determined that the port with the target wavelength belongs to the first-stage optical splitter. Because the difference between the first power and the second power is relatively small, it indicates that the strength of the optical signal with offset wavelength received by the target ONT is relatively low, and it indicates that the test optical signal with target wavelength does not amplify the optical signal with offset wavelength, and it can be determined that the port with target wavelength belongs to the second-stage optical splitter.

It should be noted that, if fig. 18 corresponds to the target ONT in fig. 1, the first power and the second power corresponding to the target ONT are total powers of the optical signal with offset wavelength and the service optical signal, that is, the first power is the above first total power, and the second power is the above second total power, and if fig. 18 corresponds to the target ONT in fig. 4 to fig. 9, the first power and the second power corresponding to the target ONT are powers of the optical signal with offset wavelength, that is, the first power is the above first power, and the second power is the above second power.

In a possible implementation manner, corresponding to the target ONT in fig. 1, this embodiment further provides a method for determining a port to which the target ONT is connected in the ODN, where the process may be as follows:

the method comprises the steps of obtaining third power when an optical signal received by a target ONT comprises a test optical signal with one wavelength, wherein the one wavelength is any one of multiple wavelengths, the multiple wavelengths are wavelengths corresponding to different ports of each optical splitter of an ODN, determining a difference value between the third power corresponding to each wavelength and the power of a service optical signal, and if the difference value between the third power corresponding to the first wavelength and the power of the service optical signal is smaller than a first value, determining a port connected in the ODN by the target ONT as a port corresponding to the first wavelength.

In this embodiment, the target ONT may obtain the third power when the test optical signal with one wavelength is included in the optical signal received by the target ONT. The one wavelength is any one of a plurality of wavelengths corresponding to different ports of each optical splitter of the ODN. For example, each optical splitter includes 8 ports, and the 8 ports correspond to λ 1 to λ 8, so that the target ONT can acquire 8 third powers.

The targeted ONT may calculate a difference between the third power corresponding to each wavelength and the power of the service optical signal. And judging the difference between the third power corresponding to each wavelength and the power of the service optical signal and the first value, and if the difference between the third power corresponding to the first wavelength and the power of the service optical signal is smaller than the first value, determining that a port connected by the target ONT in the ODN is a port corresponding to the first wavelength. This is because the third power corresponding to the first wavelength is relatively low, which means that the optical signal of the first wavelength is reflected and does not enter the target ONT, and then the port connected to the target ONT in the ODN is the port corresponding to the first wavelength.

In a possible implementation manner, corresponding to fig. 1, the embodiment of the present application further provides a method for determining a port to which a target ONT is connected in an ODN, where the processing may be as follows:

acquiring third power when optical signals received by a target ONT comprise test optical signals with one wavelength, wherein the one wavelength is any one of multiple wavelengths, and the multiple wavelengths are wavelengths corresponding to different ports of each optical splitter of the ODN; determining a difference value between the maximum power and a third power corresponding to each wavelength; and if the difference value of the maximum power and the third power corresponding to the target wavelength is larger than the second numerical value, determining that the port connected by the target ONT in the ODN is the port corresponding to the target wavelength.

In this embodiment, the target ONT may obtain the third power when the test optical signal with one wavelength is included in the optical signal received by the target ONT. The one wavelength is any one of a plurality of wavelengths corresponding to different ports of each optical splitter of the ODN. For example, each optical splitter includes 8 ports, and the 8 ports correspond to λ 1 to λ 8, respectively, so that the target ONT can acquire 8 third powers.

The target ONT may determine a maximum power of the plurality of third powers, then calculate a difference between the maximum power and the third power corresponding to each wavelength, and when the difference between the maximum power and the third power corresponding to the target wavelength is greater than a second value, the target ONT may determine that a port connected in the ODN is a port corresponding to the target wavelength. For example, if the target ONT is connected to the port corresponding to λ 1 and the port corresponding to λ 8 of the ODN, it may be determined that the difference between the maximum power and the third power corresponding to λ 1 is greater than the second value, and the difference between the maximum power and the third power corresponding to λ 8 is greater than the second value.

It should be noted here that, in the flow shown in fig. 18, the ONT is used as an execution subject to determine the level of the optical splitter to which the port of the target ONT connected in the ODN belongs, but in this embodiment of the present application, the OLT may also be used as an execution subject to determine the level of the optical splitter to which the port of the target ONT connected in the ODN belongs, and the port of the target ONT connected in the ODN is determined to be the same as the flow in the ONT, except that the target ONT needs to send the power detected by the target ONT to the OLT. The target ONT may send the first power and the second power detected by the ONT to the OLT, and after the OLT receives the first power and the second power, a difference between the first power and the second power may be determined, and the subsequent processing may be referred to as the processing of the execution main body by the ONT. Specifically, the target OLT may control the tunable wavelength laser to emit a test optical signal of a target wavelength, and send a notification to the target ONT to send the detected first power, and the target OLT may also control the tunable wavelength laser to emit a test optical signal of a target wavelength, and stop outputting the test optical signal of the target wavelength, only output an optical signal of an offset wavelength, send a notification to the target ONT, and send the detected second power. The target ONT may send the detected first power to the OLT, and the target ONT may also send the detected second power to the OLT, and the OLT determines a reception order of the first power and the second power, takes the first received power as the first power, and takes the second received power as the second power. Of course, the targeted ONT may send intermediate process data to the OLT. For example, the targeted ONT sends a difference of the first power and the second power to the OLT.

In the above description, the ONT is used as an execution subject to determine a port to which a target ONT is connected in the ODN, but in this embodiment of the application, the OLT may also be used as an execution subject to determine a port to which the target ONT is connected in the ODN. The ONT may also send the third power corresponding to each wavelength to the OLT, and the OLT determines a port to which the target ONT is connected in the ODN based on the third power corresponding to each wavelength. Or the target ONT may also send intermediate processing data to the OLT, where the intermediate processing data may also include a difference between a maximum power of the third power corresponding to the multiple wavelengths and the third power corresponding to each wavelength, and the OLT determines, based on each difference, a port to which the target ONT is connected in the ODN. Specifically, the OLT controls the tunable wavelength laser to emit test optical signals with multiple wavelengths according to a preset wavelength sequence, and the OLT issues a notification to the target ONT to instruct the target ONT to send multiple detected powers to the OLT. The targeted ONTs may send to the OLT in the order in which power was detected. Thus, the OLT may sequentially correspond the multiple wavelengths to the power transmitted by the target ONT based on the sequence of the transmission power of the target ONT, that is, obtain the third power corresponding to each wavelength.

It should be noted that, in the above description, the principle that the test optical signal of the target wavelength amplifies the optical signal of the offset wavelength is the stimulated brillouin amplification effect, and the test optical signal of the target wavelength is used as the pump light. As shown in fig. 19, a schematic diagram that the test optical signal with the target wavelength amplifies the optical signal with the offset wavelength at the port corresponding to the target wavelength of the first-stage optical splitter is also provided.

In addition, as shown in fig. 20, the above-described port identification apparatus includes a memory 2001 and a processor 2002. The Memory 2001 may be a Read-Only Memory (ROM), a static Memory device, a dynamic Memory device, or the like. The memory 2001 may store computer instructions that, when executed by the processor 2002 stored in the memory 2001, the processor 2002 is configured to perform a method of fault localization. The memory may also store data. Processor 2002 may employ a general-purpose Central Processing Unit (CPU), an application ASIC, a Graphics Processing Unit (GPU), or any combination thereof. The processor 2002 may include one or more chips.

Fig. 21 is a block diagram of an apparatus for determining a port to which an optical network terminal is connected according to an embodiment of the present application. The apparatus may be implemented as part or all of an apparatus by software, hardware, or a combination of the two, and the apparatus provided in this embodiment of the present application may implement the process described in embodiment 18 of the present application, where the apparatus includes: an obtaining module 2110 and a determining module 2120, wherein:

an obtaining module 2110, configured to obtain a difference between a first power and a second power corresponding to a target ONT, where a wavelength corresponding to a port of the target ONT connected in an optical distribution network ODN is a first wavelength, and one wavelength included in the first wavelength is a target wavelength; the offset wavelength is a wavelength obtained by offsetting the target wavelength by a target value, and the first power and the second power are powers when optical signals received by the target ONT include optical signals with the offset wavelength; when the first power is corresponded, the optical signal input to the ODN comprises a test optical signal with the target wavelength and an optical signal with the offset wavelength; when the second power is corresponding, the optical signal input into the ODN includes the optical signal with the offset wavelength and does not include the test optical signal with the target wavelength, where power of the test optical signal with the target wavelength after being reflected at a port corresponding to the target wavelength of the first stage optical splitter of the ODN is greater than or equal to a threshold value for generating a brillouin amplification effect, and power of the test optical signal with the target wavelength after being reflected at a port corresponding to the target wavelength of the second stage optical splitter of the ODN is less than the threshold value for generating the brillouin amplification effect, which may be specifically used to implement the obtaining function in step 1801 and the implicit step included in step 1801;

a determining module 2120, configured to determine that a port corresponding to the target wavelength belongs to the first-stage optical splitter of the ODN if the difference is greater than or equal to a target threshold; if the difference is smaller than the target threshold, it is determined that the port corresponding to the target wavelength belongs to the second-stage optical splitter of the ODN, and the determination function in step 1802 and the implicit step included in step 1802 may be specifically implemented.

In a possible implementation manner, the obtaining module 2110 is further configured to obtain a third power when an optical signal received by the target ONT includes a test optical signal with one wavelength, where the one wavelength is any one of multiple wavelengths, and the multiple wavelengths are wavelengths corresponding to different ports of each optical splitter of the ODN;

the determining module 2120 is further configured to determine a difference between the third power corresponding to each wavelength and the power of the service optical signal; if the difference between the third power corresponding to the first wavelength and the power of the service optical signal is smaller than a first value, determining that a port to which the target ONT is connected in the ODN is a port corresponding to the first wavelength.

The division of the modules in the embodiments of the present application is illustrative, and is only a logical function division, and in actual implementation, there may be another division manner, and in addition, each functional module in each embodiment of the present application may be integrated in one processor, may also exist alone physically, or may also be integrated in one module by two or more modules. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode.

In the above embodiments, all or part of the implementation may be implemented by software, hardware, firmware or any combination thereof, and when implemented by software, all or part of the implementation may be implemented in the form of a computer program product. The computer program product comprises one or more computer instructions which, when loaded and executed on the OLT, cause the processes or functions according to the embodiments of the application to take place in whole or in part. The computer instructions may be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium. The computer readable storage medium may be any available medium that can be accessed by the OLT or a data storage device comprising one or more integrated servers, data centers, and the like. The usable medium may be a magnetic medium (such as a floppy Disk, a hard Disk, a magnetic tape, etc.), an optical medium (such as a Digital Video Disk (DVD), etc.), or a semiconductor medium (such as a solid state Disk, etc.).

Claims

1. An optical network terminal ONT is characterized in that the ONT comprises an optical fiber interface, an optical receiving component, an optical transmitting component, a first filter, a second filter and a processor;

the first filter is arranged between the optical fiber interface and the light emission component, the light emission component is positioned on a transmission light path of the first filter, and the first filter is used for transmitting an uplink light signal emitted by the light emission component to the optical fiber interface;

the light receiving assembly and the second filter are positioned on a reflected light path of the first filter;

the first filter is further configured to reflect the test optical signal and the service optical signal received by the optical fiber interface to the second filter;

the second filter is used for transmitting the test optical signal and the service optical signal to the optical receiving component, the wavelength of the test optical signal is different from that of the service optical signal, and the test optical signal is sent by an adjustable wavelength laser at the side of an Optical Line Terminal (OLT);

the processor is electrically connected with the light receiving assembly;

the processor is configured to determine a first difference between each total power of the received test optical signal and the service optical signal and the power of the service optical signal, determine a first wavelength of the received test optical signal when the first difference is smaller than a first value, and determine a port of an Optical Distribution Network (ODN) to which the ONT is connected as a port corresponding to the first wavelength; or,

the processor is configured to determine a second difference between the maximum total power and each total power of the received test optical signal and the traffic optical signal, and determine a first wavelength of the received test optical signal when the second difference is greater than a second value; determining that a port of an ODN to which the ONT is connected is a port corresponding to the first wavelength, where the maximum total power is a maximum value of multiple total powers of the test optical signal and the service optical signal received by the optical receiving component.

2. The ONT of claim 1, wherein the processor is further configured to determine a third difference between a first total power and a second total power, the first total power and the second total power being powers at which the test optical signal received by the optical receiving component comprises an optical signal at an offset wavelength; when the first total power is corresponded, the optical signal input to the ODN comprises a test optical signal with a target wavelength and an optical signal with the offset wavelength; when corresponding to the second total power, the optical signal input into the ODN includes the optical signal of the offset wavelength and does not include the test optical signal of the target wavelength; the offset wavelength is a wavelength obtained by offsetting a target value by the target wavelength, the power of a test optical signal of the target wavelength after being reflected at a port corresponding to the target wavelength of a first-stage optical splitter of an ODN is greater than or equal to a threshold value for generating a brillouin amplification effect, the power of a test optical signal of the target wavelength after being reflected at a port corresponding to the target wavelength of a second-stage optical splitter of the ODN is less than the threshold value for generating the brillouin amplification effect, and the target wavelength is one of the first wavelengths when the first wavelength includes multiple wavelengths;

if the third difference is greater than or equal to a target threshold, determining that the port corresponding to the target wavelength belongs to the first-stage optical splitter of the ODN; and if the third difference is smaller than the target threshold, determining that the port corresponding to the target wavelength belongs to a second-stage optical splitter of the ODN.

3. The wavelength-tunable laser is characterized by comprising a laser, a beam splitter, a first optical modulator and a light combiner, wherein the beam splitter comprises a first light outlet and a second light outlet;

the laser is used for outputting test optical signals with various wavelengths;

the beam splitter is positioned between the laser and the first optical modulator, the beam splitter is positioned at a light outlet of the laser, and the first optical modulator is positioned at a first light outlet of the beam splitter;

the beam splitter is configured to split a test optical signal of a target wavelength entering the beam splitter into a first test optical signal and a second test optical signal, and output the first test optical signal and the second test optical signal through the first light outlet and the second light outlet, respectively, where the target wavelength belongs to the multiple wavelengths;

the light combiner is positioned at a light outlet of the first light modulator and a second light outlet of the beam splitter;

the first optical modulator is used for shifting the wavelength of the first test optical signal by a target value to obtain an optical signal with shifted wavelength, and the optical combiner is used for combining the second test optical signal and the optical signal with shifted wavelength and outputting the combined optical signal;

the power of the second test optical signal after being reflected at the port corresponding to the target wavelength of the first-stage optical splitter of the optical distribution network ODN is greater than or equal to the threshold value for generating the brillouin amplification effect, and the power of the second test optical signal after being reflected at the port corresponding to the target wavelength of the second-stage optical splitter of the ODN is smaller than the threshold value for generating the brillouin amplification effect.

4. The tunable wavelength laser of claim 3, further comprising a second optical modulator;

the second light modulator is positioned between the second light outlet of the beam splitter and the light combiner;

the second optical modulator is used for adjusting the power of the second test optical signal entering the second optical modulator.

5. A system for determining the topology of an optical access network, the system comprising a tuneable wavelength laser, an optical network termination, ONT, and a wavelength division multiplexer or coupler, wherein:

the tunable wavelength laser is the tunable wavelength laser of claim 3 or 4;

the ONT is the ONT of claim 1 or 2;

the wavelength division multiplexer or the coupler is used for combining the service optical signal and the test optical signal into a beam of optical signal.

6. The system of claim 5, further comprising an Optical Distribution Network (ODN);

the ODN is connected with the wavelength division multiplexer or the coupler, and the ODN is connected with the ONT;

the ODN comprises a first-stage optical splitter and a second-stage optical splitter, wherein reflection gratings are arranged at ports of the first-stage optical splitter and the second-stage optical splitter, and the wavelength of an optical signal which can be reflected by the reflection gratings is different from the wavelength of a service optical signal.

7. The system of claim 6, wherein the ports of the first stage splitter are provided with a reflective grating of the same wavelength as the ports of each of the second stage splitters;

for any one of the first-stage optical splitter and the second-stage optical splitter, each port of the optical splitter adopts reflection gratings with different wavelengths.

8. A system according to any of claims 5 to 7, characterized in that said tunable wavelength laser is arranged in an optical line termination OLT.

9. A method of outputting a test optical signal, characterized by applying to the tunable wavelength laser according to claim 3 or 4; the method comprises the following steps:

outputting a test optical signal with a target wavelength, wherein the target wavelength belongs to the wavelengths of a plurality of test optical signals which can be output by the tunable wavelength laser;

dividing the test optical signal with the target wavelength into two optical signals, wherein the two optical signals comprise a first test optical signal and a second test optical signal;

carrying out wavelength offset processing on the first test optical signal to obtain an optical signal with offset wavelength;

and synthesizing the second test optical signal and the optical signal with the offset wavelength, and outputting the synthesized optical signal, wherein the power of the second test optical signal after being reflected at a port corresponding to the target wavelength of a first-stage optical splitter of an Optical Distribution Network (ODN) is greater than or equal to a threshold value for generating a Brillouin amplification effect, and the power of the second test optical signal after being reflected at a port corresponding to the target wavelength of a second-stage optical splitter of the ODN is less than the threshold value for generating the Brillouin amplification effect.

10. The method of claim 9, further comprising:

adjusting the power of the second test optical signal;

said combining said second test optical signal and said offset wavelength optical signal comprises:

and synthesizing the optical signal with the shifted wavelength and the second test optical signal with the adjusted power.

11. The method according to claim 9 or 10, wherein the target wavelength is a wavelength corresponding to a port to which the target optical network terminal ONT is connected in an optical distribution network ODN; the test optical signal with the target wavelength is used for testing the level of an optical splitter to which a port of the target optical network terminal ONT connected in the ODN belongs, and the target wavelength is one of wavelengths corresponding to the port of the target optical network terminal ONT connected in the ODN;

before the combining the second test optical signal and the optical signal with the offset wavelength, the method further includes:

receiving a wavelength output instruction sent by an optical line terminal OLT, wherein the wavelength output instruction is used for instructing to output a test optical signal of the target wavelength;

the method further comprises the following steps:

receiving a closing instruction of the second testing optical signal sent by the OLT;

and stopping outputting the second test optical signal, and outputting the optical signal with the offset wavelength.

12. The method according to claim 9 or 10, wherein before outputting the test optical signal at the target wavelength, the method further comprises:

receiving a closing instruction of the optical signal with the offset wavelength sent by the OLT and sending out instructions of the various test optical signals;

turning off the output of the offset wavelength optical signal;

and outputting the plurality of test optical signals according to a preset wavelength sequence of the test optical signals, wherein the plurality of test optical signals are used for determining a port of a target ONT connected in the ODN.

13. A method of determining a port to which an optical network termination, ONT, is connected, for use with the ONT of claim 1 or 2 or the system of any one of claims 5 to 8, the method comprising:

acquiring a difference value between first power and second power corresponding to a target ONT, wherein a wavelength corresponding to a port connected by the target ONT in an Optical Distribution Network (ODN) is a first wavelength, and one wavelength included in the first wavelength is a target wavelength; the offset wavelength is a wavelength obtained by offsetting the target wavelength by a target value, and the first power and the second power are powers when optical signals received by the target ONT include optical signals with the offset wavelength; when the first power is corresponded, the optical signal input to the ODN comprises a test optical signal of the target wavelength and an optical signal of the offset wavelength; when the second power is corresponded, the optical signal input into the ODN includes an optical signal with the offset wavelength and does not include a test optical signal with the target wavelength, the power of the test optical signal with the target wavelength after being reflected at a port corresponding to the target wavelength of a first-stage optical splitter of the ODN is greater than or equal to a threshold value for generating a brillouin amplification effect, and the power of the test optical signal with the target wavelength after being reflected at a port corresponding to the target wavelength of a second-stage optical splitter of the ODN is less than the threshold value for generating the brillouin amplification effect;

if the difference is larger than or equal to a target threshold, determining that the port corresponding to the target wavelength belongs to a first-stage optical splitter of the ODN; and if the difference is smaller than the target threshold, determining that the port corresponding to the target wavelength belongs to a second-stage optical splitter of the ODN.

14. The method of claim 13, further comprising:

acquiring third power when an optical signal received by the target ONT comprises a test optical signal with one wavelength, wherein the one wavelength is any one of multiple wavelengths, and the multiple wavelengths are wavelengths corresponding to different ports of each optical splitter of the ODN;

determining a difference value between the third power corresponding to each wavelength and the power of the service optical signal;

if the difference between the third power corresponding to the first wavelength and the power of the service optical signal is smaller than a first value, determining that a port to which the target ONT is connected in the ODN is a port corresponding to the first wavelength.

15. An apparatus for determining a port to which an optical network termination, ONT, is connected, when applied to the ONT of claim 1 or 2 or the system of any one of claims 5 to 8, the apparatus comprising:

an obtaining module, configured to obtain a difference between a first power and a second power corresponding to a target ONT, where a wavelength corresponding to a port of the target ONT connected in an Optical Distribution Network (ODN) is a first wavelength, and one wavelength included in the first wavelength is a target wavelength; the offset wavelength is a wavelength obtained by offsetting the target wavelength by a target value, and the first power and the second power are powers when optical signals received by the target ONT include optical signals with the offset wavelength; when the first power is corresponded, the optical signal input to the ODN comprises a test optical signal with the target wavelength and an optical signal with the offset wavelength; when the second power is corresponded, the optical signal input into the ODN includes the optical signal with the offset wavelength and does not include the test optical signal with the target wavelength, the power of the test optical signal with the target wavelength after being reflected at the port corresponding to the target wavelength of the first stage optical splitter of the ODN is greater than or equal to the threshold value for generating the brillouin amplification effect, and the power of the test optical signal with the target wavelength after being reflected at the port corresponding to the target wavelength of the second stage optical splitter of the ODN is less than the threshold value for generating the brillouin amplification effect;

a determining module, configured to determine that a port corresponding to the target wavelength belongs to a first-stage optical splitter of the ODN if the difference is greater than or equal to a target threshold; and if the difference is smaller than the target threshold, determining that the port corresponding to the target wavelength belongs to a second-stage optical splitter of the ODN.

16. The apparatus of claim 15, wherein the obtaining module is further configured to obtain a third power when the optical signal received by the target ONT includes a test optical signal with one wavelength, where the one wavelength is any one of multiple wavelengths, and the multiple wavelengths are wavelengths corresponding to different ports of each optical splitter of the ODN;

the determining module is further configured to determine a difference between the third power corresponding to each wavelength and the power of the service optical signal; if the difference between the third power corresponding to the first wavelength and the power of the service optical signal is smaller than a first value, determining that a port, to which the target ONT is connected in the ODN, is a port corresponding to the first wavelength.