WO2014012256A1

WO2014012256A1 - Optical network monitoring module, optical communication network, and optical network monitoring method

Info

Publication number: WO2014012256A1
Application number: PCT/CN2012/078972
Authority: WO
Inventors: 李书; 陈聪
Original assignee: 华为技术有限公司
Priority date: 2012-07-20
Filing date: 2012-07-20
Publication date: 2014-01-23
Also published as: CN102893539B; CN102893539A

Abstract

The present invention is applicable to the field of communications, and provides an optical network monitoring module, an optical communication network, and an optical network monitoring method. The monitoring module comprises: a first emitting device, used for emitting a downstream light wave; a first receiving device, used for receiving a first reflection light of the downstream light wave reflected by an optical network; a second emitting device, used for emitting a test light wave having the same wavelength with an upstream light wave; and a second receiving device, used for receiving a second reflection light of the upstream light wave and the test light wave reflected by the optical network. In the present invention, by combining the reflection light detection of the downstream light wave and the test light wave, the test capability is improved; the wavelengths of the test light wave and the upstream light wave are the same, so that the present invention is especially applicable to a networking environment having a limited dynamic range and a great branch ratio, thereby effectively solving a problem that an detection effect is poor due to a relatively weak reflection energy, so as to realize accurate and effective monitoring on the optical network with the great branch ratio, and improving the stability of communication services.

Description

Optical network monitoring module, optical communication system and optical network monitoring method

Technical field

The invention belongs to the field of communications, and in particular relates to an optical network monitoring module, an optical communication system and an optical network monitoring method.

Background technique

As users' demand for bandwidth continues to increase, traditional copper broadband access systems are increasingly facing bandwidth bottlenecks. At the same time, fiber-optic communication technologies with huge bandwidth capacity are becoming more mature, and application costs are declining year by year, making fiber access networks become A strong competitor for the next generation of broadband access networks, especially passive optical networks are more competitive.

The typical optical access network topology consists of an OLT (Optical Line Terminal) located in the central office. , an optical line terminal) and a number of point-to-multipoint structures consisting of ONUs (Optical Network Units) on the user side, the OLT is at a predetermined wavelength (eg 1490nm) light is used as the downlink communication carrier, while ONU is at another predetermined wavelength (such as 1310nm) The light is the uplink communication carrier. The two devices are connected by an optical fiber that passes through the optical splitter.

As the network layout continues to spread, the coverage of optical networks continues to expand. In this large-scale application environment, monitoring of the fiber network becomes very important in order to ensure the stability of the communication service. How to realize low-cost and effective test monitoring of optical networks has become a hot spot of current concern.

The industry's common monitoring method is to use OTDR (Optical Time Domain Refletometer, Optical time domain reflectometer) to detect and locate faults in optical networks. OTDR The basic principle is to detect the fault of the optical network and the location of the fault by using the retroreflection generated when the light wave propagates in the optical network. Specifically, a certain wavelength of light is incident on the optical network, and then the corresponding reflected light energy is measured. The size of the optical network reflects the state of the optical network, and different wavelengths have different reflection characteristics during transmission. The detection method is divided into external and built-in two types, as shown in the figure. 1-1 and 1-2, as the name implies, the difference between external and built-in is the difference of the detection devices used. The external method uses large independent OTDR equipment through optical splitter or WDM (wavelength division multiplexing). The device is connected to the optical network for measurement and monitoring, and the built-in method is to integrate the detection device into the optical module for small integration, although the built-in OTDR In terms of performance characteristics such as dynamic range, it is inferior to external type, but it is a hot spot because it can be perfectly integrated with existing networks and is cheaper than external methods. Built-in OTDR Generally, the internal device is shared with the optical module. The test medium generally adopts the OLT downlink data wavelength. This test method performs network monitoring by measuring the amount of back reflection of the downlink data wavelength.

In the prior art, an OLT optical module structure integrated with an optical time domain reflectometer function is shown in FIG. 2, wherein the device F1, F2, F3, and F4 are all coated, F1 and F2 act as splitting, F3 and F4 are isolated, and the downstream light emitted by the laser passes through F1 and F2. The two-way optical path entering the uppermost vertical direction is transmitted to the optical fiber network, and F2 reflects the upstream optical wave from the optical network to be received by the first photodetector. At the same time, F2 Through the descending light wave and its reflected wave, the reflected wave is reflected by F1 to the second photodetector, and the condition of the optical fiber network is tested by detecting the part of the light energy.

This solution is based on the existing optical module structure, adding a new WDM device and receiver (second photodetector) to achieve OTDR The function. However, the scheme uses a single wavelength (wavelength of the descending light wave) to test, due to the limitation of the dynamic range of the system, the ratio of large branches such as 1:32 and 1:64 (OLT and ONU) The proportion of the network environment, the back-end network reflected back the light is very weak, can not achieve good monitoring of network conditions.

technical problem

The purpose of embodiments of the present invention is to provide An optical network monitoring module aims to solve the shortcomings of the existing built-in optical time domain reflectometer in network monitoring capability, so as to achieve effective monitoring of large branches than optical networks.

Technical solution

The embodiments of the present invention provide the following technical solutions:

first,

An optical network monitoring module is provided, including:

a first transmitting device for transmitting a downward light wave;

a first receiving device, configured to receive first reflected light reflected by the downlink optical wave through the optical network;

a second transmitting device, configured to emit a test light wave having the same wavelength as the upstream light wave;

The second receiving device is configured to receive an uplink light wave and a second reflected light that is reflected back by the test light wave through the optical network.

Specifically, the first transmitting device and the first receiving device are connected to the first waveguide by using the first optical splitter;

The first waveguide is configured to output the downlink optical wave to the optical network, and transmit the first reflected light to the first receiving device by using the first optical splitter;

The second transmitting device and the second receiving device are connected to the second waveguide through the second optical splitter;

The second waveguide is configured to output the test light wave to the optical network, and transmit the second reflected light and the upstream light wave to the second receiving device through the second optical splitter.

Further, the optical network monitoring module further includes a third waveguide, configured to perform coupling transmission with the first waveguide and the second waveguide, output the downlink optical wave and the test optical wave to the optical network, and output the first reflection Light is coupled to the first waveguide, coupling the second reflected light and the upstream light wave to the second waveguide.

Further, the ends of the first waveguide, the second waveguide, and the third waveguide are both tapered structures for improving coupling efficiency.

Preferably, the ratio of the energy of the downward optical wave outputted by the first optical splitter to the first waveguide to the energy of the first reflected light outputted to the first receiving device is 9:1;

a ratio of an energy of an upstream light wave outputted by the second optical splitter to the second receiving device and an energy of a test light wave outputted to the second waveguide is 9:1.

Further, the optical network monitoring module further includes:

a coating mirror for reflecting or transmitting a downward optical wave outputted by the first waveguide to the optical network, and reflecting or transmitting the first reflected light to the first waveguide;

Transmitting or reflecting the test light wave outputted by the second waveguide to the optical network, and transmitting or reflecting the upstream light wave and the second reflected light to the second waveguide.

Further, the coating mirror is integrated with the first waveguide and the second waveguide.

Alternatively, the optical network monitoring module further includes:

a diffraction grating for coupling a downward optical wave output by the first waveguide and a test optical wave output by the second waveguide into the optical network, and coupling the first reflected light to the first waveguide, and the second reflected light and the uplink The light waves are coupled to the second waveguide.

Further, the optical network monitoring module further includes:

a third transmitting device, configured to emit a third optical wave different from a wavelength of the descending light wave and the test light wave;

The third reflected light reflected by the third optical wave via the optical network is received by the first receiving device or the second receiving device.

The second aspect,

An optical communication system is provided, comprising an optical line termination and an optical network unit, the optical line termination comprising the optical network monitoring module described above.

The third aspect,

An optical network monitoring method is provided, the method comprising the steps of:

Transmitting a downward wave of light to the optical network;

Receiving the first reflected light reflected by the downlink optical wave through the optical network;

Transmitting, to the optical network, test light waves having the same wavelength as the upstream light wave;

Receiving a second reflected light reflected by the test light wave through the optical network;

The working state of the optical network is judged according to the light wave reflected from the optical network.

Specifically, the wavelength of the descending light wave is 1490 nm; and the wavelength of the upstream light wave is 1310 nm.

Further, before the determining, according to the optical wave reflected by the optical network, the working state of the optical network, the method further includes:

Transmitting, to the optical network, a third optical wave having a different wavelength from the descending optical wave and the upstream optical wave;

Receiving a third reflected light reflected by the third optical wave through the optical network.

Beneficial effect

The monitoring module provided by the embodiment of the invention adopts PLC (Planar Light-wave Circuit) , planar optical waveguide line) four-way (including: upper and lower data optical path and test wavelength of the emission optical path and reflected light receiving optical path) structure, combining the descending light wave and the reflected light detection of the test light wave, the test range covers two wavelengths In addition, the test light wave used in this embodiment has the same wavelength as the upstream light wave. Since the end of the network has the same light reflectance as the wavelength of the upstream light wave, it is regarded as the wavelength to be detected, and is dynamic. The networking environment with limited scope and large branch ratio is especially suitable, which can effectively solve the problem of poor detection effect caused by weak reflection energy at the back end of the network, and realize accurate and effective monitoring of the optical network with large branch ratio, thereby improving communication. Business stability.

DRAWINGS

Figure 1-1 is a schematic diagram of a system structure of an optical network monitoring using an external OTDR in the prior art;

Figure 1-2 is a schematic diagram of the system structure of the prior art using the built-in OTDR for optical network monitoring;

2 is a schematic structural diagram of an OLT optical module integrated with an optical time domain reflectometer in the prior art;

3 is a schematic structural diagram (1) of an optical network monitoring module according to a first embodiment of the present invention;

4 is a schematic structural diagram of an optical network monitoring module according to a first embodiment of the present invention (2);

FIG. 5 is a schematic structural diagram of an optical network monitoring module according to a first embodiment of the present invention (3);

6 is a schematic structural diagram of an optical network monitoring module according to a first embodiment of the present invention (4);

FIG. 7 is a flowchart of an optical network monitoring method according to a second embodiment of the present invention.

Embodiments of the invention

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The specific implementation of the present invention is described in detail below in conjunction with specific embodiments:

实施例一： Embodiment 1:

Figure 3 shows a first embodiment of the present invention A schematic diagram of the structure of the optical network monitoring module. For the convenience of description, only the parts related to the present embodiment are shown.

The optical network monitoring module includes a first transmitting device 101, a first receiving device 102, and a second transmitting device 103. And a second receiving device 104. Wherein: the first launching device 101 The downlink optical wave is transmitted to the optical network, and the downlink optical wave is partially reflected by the backscattering or the fault during the transmission to the user end, and the first reflected light reflected by the optical network is returned along the original optical path, and the first receiving is performed. Device 102 Receiving, the first reflected light serves as a data basis for monitoring work as a light wave to be detected. In addition, the second transmitting device 103 Transmitting a test light wave to the optical network, the test light wave is the same as the wavelength of the uplink light wave transmitted by the user end to the network office end, and the test light wave is also partially reflected by backscattering or fault, and the second reflected light reflected back is received by the second Device 104 Receiving, the second reflected light serves as data for monitoring work as another light wave to be detected. In the actual monitoring work, by detecting the reflected wave of the downstream light wave and the test light wave, the data of the downlink light wave, the test light wave and the reflected wave are processed by using a preset algorithm to realize real-time detection of the network fault and ensure the stability of the network state. .

The monitoring module provided by the embodiment of the invention adopts PLC (Planar Light-wave Circuit) , planar optical waveguide line) four-way structure, combining the reflected light wave and the reflected light detection of the test light wave, the test range covers two wavelengths, so that the test capability is improved; and, the test light wave and the upward light wave used in the embodiment The wavelength is the same. Since the end of the network has the same light reflectance as the wavelength of the upstream light wave, it is used as the wavelength to be detected. It is especially suitable for the networking environment with limited dynamic range and large branch ratio. The problem of poor detection effect caused by weak reflection energy enables accurate and effective monitoring of optical networks with large branch ratios, thereby improving the stability of communication services.

The monitoring module in the embodiment of the present invention can be used for 1490nm downlink light wave and 1310nm upstream light wave. The optical network, that is, the wavelength of the downward light wave emitted by the first transmitting device 101 is 1490 nm, and the wavelength of the test light wave emitted by the second transmitting device 103 is 1310 nm.

Further referring to FIG. 3, preferably, the first transmitting device 101, the first receiving device 102, and the second transmitting device 103 And the second receiving device 104 performs input and output of the optical signal through the waveguide. Specifically, the first transmitting device 101 and the first receiving device 102 can pass through the optical splitter (the first optical splitter 105) Connecting a waveguide (the first waveguide 106), and outputting the downward optical wave emitted by the first transmitting device 101 to the optical network through the first waveguide 106 while passing through the first waveguide 106. The first reflected light reflected by the optical network is received, and the first reflected light is transmitted to the first receiving device 102 through the first optical splitter 105. Similarly, the second transmitting device 103 and the second receiving device 104 The second waveguide 108 is connected by the second optical splitter 107, and the second transmitting device 103 is passed through the second waveguide 108. The emitted test light wave is output to the optical network, and the second reflected light reflected by the optical network and the upstream light wave transmitted by the user end are received and transmitted to the second receiving device 104 through the second optical splitter 107.

Further, the module may further include a third waveguide 109, and the first waveguide 106 and the second waveguide 108. Coupling, the third waveguide 109 is a direct interaction channel between the monitoring module and the optical network, and the downstream optical wave and the second waveguide 108 output from the first waveguide 106 are on the one hand. The output test light waves are output directly to the optical network, and on the other hand, the first reflected light reflected by the optical network is coupled to the first waveguide 106, and the second reflected light and the upstream optical wave are coupled to the second waveguide 108.

Further, referring to FIG. 4, the first transmitting device 101 and the first receiving device 102 may also pass through the fourth waveguide 110, respectively. The first optical splitter 105 is connected to the fifth waveguide 111, and the descending optical wave is input to the first optical splitter 105 through the fourth waveguide 110, and the first reflected light is output to the fifth waveguide through the first optical splitter 105. 111, and then input to the first receiving device 102. Similarly, the second transmitting device 103 and the second receiving device 104 can pass through the sixth waveguide 112 and the seventh waveguide 113, respectively. Connected to the second optical splitter 107, the test optical wave is input to the second optical splitter 105 through the sixth waveguide 112, and the second reflected light and the upstream optical wave are output to the seventh waveguide through the second optical splitter 107. And further input to the second receiving device 104.

In the embodiment of the present invention, the uplink, the descending light wave, the test light wave, and the first and second reflected light are transmitted through the waveguide, and the installation position and the relative distance of each device are relatively flexible compared to the conventional method of using the spatial light coupling. The amplitude reduces the module volume; and the spatial optical coupling method requires extremely high assembly precision of each device, which is easy to cause test error. The waveguide is used for optical transmission, and complicated and fine optical path control is not required, which facilitates device assembly and can reduce testing. Errors, which in turn reduce assembly costs.

As a modification of the embodiment, the first waveguide 106, the second waveguide 108, and the third waveguide 109 may be The end portion is processed, and the end portion of each waveguide coupled with the other waveguide is tapered, and the specific shape thereof is gradually increased along the non-terminal end surface of the waveguide to increase the incident area of the end surface, and the light is incident. The surface can be adjusted as needed to achieve the accommodating reception of the incident light, thereby improving the coupling efficiency of the light wave.

Further, the first optical splitter 105 and the second optical splitter 107 may be used. The split ratio is designed. Preferably, the ratio of the energy of the descending light wave outputted by the first optical splitter 105 to the first waveguide 106 to the energy of the first reflected light outputted to the first receiving device 102 is 9:1. In order to ensure that the reception of the first reflected light does not affect the transmission and quality of the downstream optical wave, and ensure the smooth transmission of the downstream optical wave. The second optical splitter 107 is directed to the second receiving device 104 The ratio of the energy of the output upstream light wave to the energy of the test light wave outputted to the second waveguide 108 is 9:1, ensuring that the test light wave does not affect the reception quality of the upstream light wave.

In an embodiment of the invention, a device for cooperating with optical wave coupling transmission may also be included. Preferably, the device can be a coated mirror 114 The coating mirror 114 can selectively reflect and transmit the light wave, and the coating mirror 114 reflects the descending light wave outputted by the first waveguide 106 toward the optical network, and can be reflected into the third waveguide 109 by the third waveguide. 109. The optical network is input, and at the same time, the first reflected light transmitted by the third waveguide 109 is reflected into the first waveguide 106, and is output from the first waveguide 106 to the first receiving device 102. And the coated mirror 114, the test light wave output from the second waveguide 108 is also transmitted to the third waveguide 109, and the third waveguide 109 is input to the optical network while the third waveguide 109 is The transmitted upstream light and the second reflected light are transmitted to the second waveguide 108 and transmitted by the second waveguide 108 to the second receiving device 104.

Specifically, the coating mirror 114 is disposed between the first waveguide 106 and the second waveguide 108, and the coating mirror 114 An air gap is formed between the first, second, and third waveguides. As shown in FIG. 3, the first transmitting device 101, the first receiving device 102 is placed on the left side of the coating mirror 114 - the reflective side, and the second transmitting device 103 And the second receiving device 104 is placed on the right side of the coating mirror 114 - the light transmitting side, and the descending light wave is outputted by the first waveguide 106 and then reflected by the coating mirror 114, thereby being coupled into the third waveguide 109. While reflecting and coupling the first reflected light into the first waveguide 106; and transmitting and coupling the test light output from the second waveguide 108 into the third waveguide 109 The second reflected light and the upward optical wave are transmitted and coupled into the second waveguide 108. Of course, the first transmitting device 101 and the first receiving device 102 and the second transmitting device 103 and the second receiving device 104 You can also adjust the position.

In the embodiment of the present invention, the coating mirror 114 The first, second, and third waveguides may be integrally connected to each other. In actual manufacturing, the coupling ends of the first, second, and third waveguides may be previously combined with the coating mirror 114. A reasonable matching design is carried out, and the same process is used to process and coat the corresponding waveguide, so that the coating mirror 114 Forming a fixed integral structure with the first, second, and third waveguides, and the integrated structure can avoid the problem of poor matching between the lens and the waveguide, and can ensure data acquisition, compared with the manner of inserting the corresponding lens after the waveguide is configured. The accuracy of the module ensures the accuracy of the module. Of course, the device does not rule out the adoption TFF (Thin Film Filter) 115 and other devices with selective reflection and transmission, as shown in Figure 4. However, in order to avoid the problem of poor matching with the waveguide, the above-described plated film 114 is preferably used in this embodiment.

Referring to FIG. 5, as another preferred implementation, the light-wave coupling device may also be a diffraction grating 116. Also used to couple the downstream light and the test light into the optical network, couple the first reflected light to the first receiving device 102, and couple the second reflected light and the upstream light wave to the second receiving device 104. The diffraction grating 116 It can be etched and formed on the same material together with the corresponding waveguide, and is integrated with the waveguide like the coated mirror 114. Unlike the use of a coated mirror, the diffraction grating 116 can be disposed on the first waveguide. 106, the second side of the second waveguide 108 and the third waveguide 109. The descending light waves output from the first waveguide 106 pass through the diffraction grating 116 from the test light waves output from the second waveguide 108. Coupled to the third waveguide 109, the first and second reflected light and the upstream optical wave outputted through the third waveguide 109 are coupled to the corresponding first waveguide 106 and second waveguide 108 via the diffraction grating 116. Medium. By using the diffraction grating 116 and the coupling transmission of the optical signal, each of the transmitting device and the receiving device and the waveguide can be disposed on the same side of the diffraction grating 116, thereby shortening the length of the monitoring module to some extent.

As another improvement of the embodiment of the present invention, a third transmitting device 117 may be further added. A third optical wave having a different wavelength from the above-mentioned descending light wave and the test light wave is emitted, as shown in FIG. The third reflected light reflected by the third optical wave through the optical network may be used by the first receiving device 102. Receive. Specifically, a third optical splitter 118 may be added between the first optical splitter 105 and the first receiving device 102 to enable the third transmitting device 117 and the first receiving device 102. The third optical splitter 118 is connected in common, and the third reflected light is transmitted to the first receiving device 102 via the first optical splitter 105 and the third optical splitter 118. The third optical splitter 118 The split ratio can be 1:1, that is, the ratio of the energy of the third light wave outputted by the third optical splitter 118 to the third reflected light input is 1:1. . The wavelength of the third light wave can be reasonably set according to actual monitoring conditions, and can be 1650 nm or 1625 nm, and other reasonable wavelengths can be selected.

In the embodiment of the present invention, the test capability of the module is further improved by adding a third test light wave. Moreover, other test wavelengths can be continuously added according to actual needs to further expand the monitoring range.

In the actual monitoring work, the wavelength of the test can be selected according to the condition of the network to be detected, and the reflected light of the descending light wave can be detected separately, or the reflected light of the test light wave can be detected separately, or the reflected light of the third light wave can be detected. Detection is performed, of course, this embodiment preferably combines multiple wavelength detections to more accurately detect and locate network faults.

The optical network monitoring module provided by the embodiment of the present invention is applicable to an optical communication system, and the monitoring module can effectively detect information such as a fault in a fiber network and a location where a fault occurs, thereby ensuring communication stability.

Embodiment 2 FIG. 7 is a flowchart of an optical network monitoring method according to a second embodiment of the present invention. For convenience of description, only parts related to the embodiment are shown.

In step S201, a downlink optical wave is transmitted to the optical network;

In step S202, receiving first reflected light reflected by the downlink optical wave through the optical network;

In step S203, a test light wave having the same wavelength as that of the upstream light wave is transmitted to the optical network;

In step S204, receiving a second reflected light that is reflected back by the test light wave through the optical network;

In step S205, the operating state of the optical network is determined based on the light waves reflected back from the optical network.

The monitoring method provided by the embodiment of the present invention can be implemented by the optical network monitoring module provided in the first embodiment. That is, the downlink light wave is transmitted by the first transmitting device, the first reflected light is received by the first receiving device, the test light wave is emitted by the second transmitting device, and the second reflected light is received by the second receiving device. The coupling and transmission of the light wave can be performed by the corresponding waveguide and the coating mirror or the diffraction grating. The details are the same as those in the first embodiment, and are not described here.

The monitoring method combines the detection of the reflected light wave and the reflected light of the test light wave, and the test range covers the two wavelengths, thereby improving the test capability; and the test light wave has the same wavelength as the upstream light wave, due to the wavelength of the end of the network and the wavelength of the upstream light wave. The same light reflectance is high, so it is regarded as the wavelength to be detected. It is especially suitable for the networking environment with limited dynamic range and large branch ratio, which can effectively solve the problem of poor detection due to weak reflection energy at the back end of the network. To achieve accurate and effective monitoring of optical networks with large branch ratios, thereby improving the stability of communication services.

Further, the wavelength of the downlink light wave in this embodiment may be 1490 nm, and the wavelength of the uplink light wave may be 1310 nm. .

Further, a test step of the third light wave may be added, specifically: proceeding to step S205 Previously, you can also perform the following steps:

A third optical wave having a wavelength different from that of the descending optical wave and the upstream optical wave is transmitted to the optical network, and the third reflected light reflected by the optical wave through the optical network is received.

In the embodiment of the present invention, the test capability of the module is further improved by adding a third test light wave. The wavelength of the third light wave can be 1650nm or 1625nm It can also be other reasonable wavelengths. Moreover, the embodiment can also increase the test light wave according to the need and the actual network condition, so as to further expand the monitoring range and improve the stability of the communication system.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. Within the scope.

Claims

An optical network monitoring module, comprising:

a first transmitting device for transmitting a downward light wave;

a first receiving device, configured to receive first reflected light reflected by the downlink optical wave through the optical network;

a second transmitting device, configured to emit a test light wave having the same wavelength as the upstream light wave;

The second receiving device is configured to receive an uplink light wave and a second reflected light that is reflected back by the test light wave through the optical network.
Claims 1 The optical network monitoring module is characterized in that the first transmitting device and the first receiving device are connected to the first waveguide through the first optical splitter.

The first waveguide is configured to output the downlink optical wave to the optical network, and transmit the first reflected light to the first receiving device by using the first optical splitter;

The second transmitting device and the second receiving device are connected to the second waveguide through the second optical splitter;

The second waveguide is configured to output the test light wave to the optical network, and transmit the second reflected light and the upstream light wave to the second receiving device through the second optical splitter.
Claims 2 The optical network monitoring module further includes a third waveguide for coupling transmission with the first waveguide and the second waveguide, and outputting the downlink optical wave and the test optical wave to the optical network, and The first reflected light is coupled to the first waveguide, and the second reflected light and the upstream optical wave are coupled to the second waveguide.
Claims 3 The optical network monitoring module is characterized in that the ends of the first waveguide, the second waveguide and the third waveguide are both tapered structures for improving coupling efficiency.
Claims 2 The optical network monitoring module is characterized in that: the ratio of the energy of the descending light wave outputted by the first optical splitter to the first waveguide to the energy of the first reflected light outputted to the first receiving device is 9 :1 ;

The ratio of the energy of the upstream light wave outputted by the second optical splitter to the second receiving device to the energy of the test light wave outputted to the second waveguide is 9:1 .
The optical network monitoring module according to any one of claims 2 to 5, further comprising:

a coating mirror for reflecting or transmitting a downward optical wave outputted by the first waveguide to the optical network, and reflecting or transmitting the first reflected light to the first waveguide;

Transmitting or reflecting the test light wave outputted by the second waveguide to the optical network, and transmitting or reflecting the upstream light wave and the second reflected light to the second waveguide.
The optical network monitoring module according to claim 6, wherein the coating mirror is integrated with the first waveguide and the second waveguide.
The optical network monitoring module according to any one of claims 2 to 5, further comprising:

a diffraction grating for coupling a downward optical wave output by the first waveguide and a test optical wave output by the second waveguide into the optical network, and coupling the first reflected light to the first waveguide, and the second reflected light and the uplink The light waves are coupled to the second waveguide.
The optical network monitoring module of claim 1 further comprising:

a third transmitting device, configured to emit a third optical wave different from a wavelength of the descending light wave and the test light wave;

The third reflected light reflected by the third optical wave via the optical network is received by the first receiving device or the second receiving device.
An optical communication system comprising an optical line termination and an optical network unit, wherein the optical line termination comprises the claims 1-9 Any optical network monitoring module.
An optical network monitoring method, characterized in that the method comprises the following steps:

Transmitting a downward wave of light to the optical network;

Receiving the first reflected light reflected by the downlink optical wave through the optical network;

Transmitting, to the optical network, test light waves having the same wavelength as the upstream light wave;

Receiving a second reflected light reflected by the test light wave through the optical network;

The working state of the optical network is judged according to the light wave reflected from the optical network.
The optical network monitoring method according to claim 11, wherein the wavelength of the descending light wave is 1490 nm; and the wavelength of the upstream light wave is 1310nm.
Claims 12 The optical network monitoring method is characterized in that: before determining the working state of the optical network according to the optical wave reflected from the optical network, the method further includes:

Transmitting, to the optical network, a third optical wave having a different wavelength from the descending optical wave and the upstream optical wave;

Receiving a third reflected light reflected by the third optical wave through the optical network.