An anti-reflection light interference detection system for optical network terminals

Abstract

The utility model relates to the field of optical communication technology, and in particular to an anti-reflection light interference detection system for an optical network terminal, comprising a terminal to be tested, a first splitter, an adjustable optical attenuator, a three-ring polarizer, a total reflection optical fiber, a second splitter, an optical oscilloscope and a spectrometer; the first splitter receives an incident light signal of the terminal to be tested, and transmits it to the adjustable optical attenuator; the incident light signal passes through the adjustable optical attenuator, the three-ring polarizer and the total reflection optical fiber in sequence to form a reflected light signal; the reflected light signal passes through the three-ring polarizer and the adjustable optical attenuator in sequence and is fed back to the first splitter; the first splitter transmits the reflected light signal to the second splitter, and transmits it to the optical oscilloscope and the spectrometer respectively through the second splitter. By adopting this scheme, the anti-reflection light capability of the terminal to be tested can be detected, which is conducive to screening and eliminating unqualified terminals to be tested, ensuring product quality, and guaranteeing the network stability of the product and the user experience.

Description

Technical Field

[0001] The utility model relates to the technical field of optical communication, in particular to an anti-reflection light interference detection system of an optical network terminal. Background Art

[0002] In today's information age, the demand for optical communication network equipment is experiencing unprecedented growth. Behind this growth is the surge in data traffic and the increasingly urgent need for high-speed, high-quality network connections. With the continuous advancement of communication technology, the reduction in hardware costs has enabled more users to access high-speed optical communication networks. However, this rapid growth has also brought a series of challenges, especially in the quality and performance of long-distance transmission ONUs (optical network terminals).

[0003] In optical communication networks, optical link reflection is a common problem that has a significant impact on the performance of ONUs. Connectors and impedance mismatches on optical links will cause reflections, and these reflected lights will interfere with the DFB (distributed feedback) laser chips of the optical modules inside the ONU, thereby affecting the performance of the lasers. In PON (passive optical network) system engineering applications, DFB lasers are affected to varying degrees by reflected light, especially the interference signals of light reflections of the same wavelength, which will cause an increase in the uplink bit error rate of mobile service links. The OLT (optical line terminal) at the local end will receive varying amounts of bit errors under varying degrees of interference from reflected light of the same wavelength. This fault will cause the user-end network speed to decrease, seriously affecting network stability and user experience.

[0004] To solve the above problems, a common practice in the optical communication industry is to add optical isolators to the optical path structure to isolate the reflected light. However, optical isolators are expensive and have almost no competitiveness in the PON network home gateway market below 10G. Therefore, optical isolators are usually not added to the optical path structure. However, the network stability of devices without optical isolators cannot be guaranteed, resulting in inconsistent quality of factory products and an inability to grasp the network stability of factory products, which affects user experience.

[0005] Therefore, in the face of the widespread impact of reflected light in optical links on ONU performance, as well as the high cost and low efficiency of existing solutions, it is urgent to propose an anti-reflection light interference detection system for optical network terminals, which can accurately verify and measure the anti-reflection light capability of ONU optical network terminals, thereby effectively eliminating unqualified ONU products, ensuring product quality, and guaranteeing network stability and user experience. Utility Model Content

[0006] The utility model provides an anti-reflection light interference detection system for an optical network terminal, which can detect the anti-reflection light capability of a terminal to be tested, is conducive to screening and eliminating unqualified terminals to be tested, ensures product quality, and guarantees product network stability and user experience.

[0007] In order to achieve the above objectives, this application provides the following technical solutions:

[0008] An anti-reflection light interference detection system for an optical network terminal comprises a terminal to be tested, a first splitter, an adjustable optical attenuator, a three-ring polarizer, a total reflection optical fiber line, a second splitter, an optical oscilloscope and a spectrometer;

[0009] The terminal to be tested, the adjustable optical attenuator and the second splitter are all connected to the optical path of the first splitter; the first splitter receives the incident optical signal of the terminal to be tested and transmits it to the adjustable optical attenuator;

[0010] One end of the three-ring polarizer is connected to the optical path of the adjustable optical attenuator, and the other end is connected to the optical path of the total reflection optical fiber line; the incident light signal passes through the adjustable optical attenuator and the three-ring polarizer in sequence, is transmitted to the total reflection optical fiber line, and generates signal reflection through the total reflection optical fiber line to form a reflected light signal; the reflected light signal passes through the three-ring polarizer and the adjustable optical attenuator in sequence, and is fed back to the first splitter; the first splitter transmits the reflected light signal to the second splitter;

[0011] The optical oscilloscope and the spectrometer are both connected to the optical path of the second splitter; the second splitter transmits the reflected light signal to the optical oscilloscope and the spectrometer respectively; the optical oscilloscope generates an eye diagram according to the reflected light signal; the spectrometer generates a spectrum diagram according to the reflected light signal.

[0012] Furthermore, it also includes a reflected light power meter connected to the optical path of the first splitter; the first splitter feeds back the received reflected light signal to the reflected light power meter; the reflected light power meter detects the optical signal intensity of the reflected light signal.

[0013] Furthermore, the first splitter is a 2:2 pull-hammer splitter.

[0014] Furthermore, the splitting ratio of the 2:2 pull-hammer splitter is 50:50.

[0015] Furthermore, the wavelength range of the 2:2 pull-hammer splitter is 1260nm to 1650nm.

[0016] Furthermore, the total reflection optical fiber line is a UPC optical fiber connector, the input end of the UPC optical fiber connector is connected to the three-ring polarizer optical path, and the output end is provided with a reflective film to reflect the incident light signal to form a reflected light signal.

[0017] Furthermore, it also includes a controller and an incident optical power meter; a switch is provided between the first splitter and the second splitter;

[0018] The incident optical power meter, the reflected optical power meter and the switch are all electrically connected to the controller; the incident optical power meter is also connected to the optical path of the terminal to be measured;

[0019] The incident optical power meter detects the optical signal intensity of the incident optical signal and feeds back the incident optical intensity detection signal to the controller;

[0020] The reflected light power meter detects the light signal intensity of the reflected light signal and feeds back the reflected light intensity detection signal to the controller;

[0021] The controller controls the on and off of the switch according to the incident light intensity detection signal and the reflected light intensity detection signal.

[0022] Furthermore, the second splitter is a 1:2 splitter.

[0023] The principles and advantages of this utility model are:

[0024] The anti-reflection light interference detection system in this solution is used to accurately and efficiently detect the anti-reflection light capability of the terminal to be tested. This solution integrates components such as the first splitter, adjustable optical attenuator, three-ring polarizer, total reflection optical fiber, second splitter, optical oscilloscope and spectrometer to jointly build a test platform that can simulate the impact of reflected light in an actual network environment.

[0025] During operation, the incident optical signal emitted by the terminal to be tested first passes through the first splitter, and then through the adjustable optical attenuator and the three-ring polarizer, which respectively accurately control the power and polarization direction of the optical signal. The addition of the adjustable optical attenuator allows engineers to adjust the power of the optical signal as needed to simulate the impact of different reflected light intensities on the communication system. The three-ring polarizer further enriches the test conditions by adjusting the polarization direction of the optical signal to simulate various polarization states that the optical signal may encounter in the actual network.

[0026] After the above regulation, the optical signal forms a reflected light signal through the total reflection optical fiber, and is fed back to the first splitter through the three-ring polarizer and the adjustable optical attenuator again. At this time, the reflected light power meter and the incident light power meter detect the optical signal intensity of the reflected light signal and the incident light signal respectively. When the difference in the optical signal intensity between the two reaches the preset threshold range, the controller turns on the switch between the first splitter and the second splitter, transmits the reflected light signal to the second splitter, and transmits it to the optical oscilloscope and the spectrometer for analysis. The eye diagram generated by the optical oscilloscope and the spectrum diagram generated by the spectrometer provide intuitive and detailed data support for analyzing the optical parameter indicators of the reflected light, thereby realizing the detection of the anti-reflection light ability of the terminal to be tested, which is conducive to engineers to screen and eliminate unqualified terminals to be tested, ensure the final product quality, and ensure the network stability of the product and the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The utility model is a schematic diagram of optical path connection of an embodiment of an anti-reflection light interference detection system for an optical network terminal.

[0028] Figure 2 The present invention is a signal flow diagram of an embodiment of an anti-reflection light interference detection system for an optical network terminal. DETAILED DESCRIPTION

[0029] The following is further described in detail through specific implementation methods:

[0030] Embodiment 1:

[0031] Embodiment 1 is basically as attached Figure 1 As shown:

[0032] An anti-reflection light interference detection system for an optical network terminal includes a terminal to be tested, an incident optical power meter, a first splitter, a reflected optical power meter, an adjustable optical attenuator, a three-ring polarizer, a total reflection optical fiber, a second splitter, an optical oscilloscope, a spectrometer and a controller. In this embodiment, the first splitter is a 2:2 pull-hammer splitter with a splitting ratio of 50:50, a wavelength range of 1260nm to 1650nm, and an optical insertion loss of 3.2dB to 3.5dB. Specifically, a 2:2 optical fiber splitter is used as the first splitter. The second splitter is a 1:2 optical fiber splitter. The model of the adjustable optical attenuator is N7752A; the model of the three-ring polarizer is PCP-XX; the model of the optical oscilloscope is DCA-X 86100D; the model of the spectrometer is AQ6370D; and the model of the controller is MKL03Z8VFG4.

[0033] In this embodiment, the terminal to be tested is an ONU terminal to be tested. When the detection starts, the ONU terminal to be tested is started and a long light is turned on. Figure 1As shown, the incident optical power meter is connected to the optical path of the terminal to be tested, and an incident optical power meter of model is used to detect the optical signal intensity of the incident optical signal.

[0034] like Figure 1 As shown, the terminal to be tested, the adjustable optical attenuator, the second splitter and the reflected light power meter are all connected to the optical path of the first splitter. A switch is provided between the first splitter and the second splitter. In this embodiment, the initial state of the switch is off. In other embodiments of the present application, the switch can also be set to normally open, so that the incident light signal can be transmitted to the optical oscilloscope and the spectrometer for detection before the reflected light signal is emitted, so as to compare the corresponding parameters of the incident light signal and the reflected light signal.

[0035] During the detection process, the terminal to be tested sends out an incident light signal, the first splitter receives the incident light signal of the terminal to be tested, and transmits it to the adjustable optical attenuator. One end of the three-ring polarizer is connected to the optical path of the adjustable optical attenuator, and the other end is connected to the optical path of the total reflection optical fiber line; the incident light signal passes through the adjustable optical attenuator and the three-ring polarizer in turn, is transmitted to the total reflection optical fiber line, and generates signal reflection through the total reflection optical fiber line to form a reflected light signal. In this embodiment, the total reflection optical fiber line is a UPC optical fiber connector of model, the input end of the UPC optical fiber connector is connected to the optical path of the three-ring polarizer, and the output end is provided with a reflective film to reflect the incident light signal to form a reflected light signal; specifically, the reflective film is fixed to the output end of the UPC optical fiber connector by pasting, so that the energy of the incident light signal is reflected back vertically.

[0036] The reflected light signal is fed back to the first splitter again through the three-ring polarizer and the adjustable optical attenuator; the first splitter feeds back the received reflected light signal to the reflected light power meter; and the optical signal intensity of the reflected light signal is detected by the reflected light power meter.

[0037] like Figure 2 As shown, the incident optical power meter, the reflected optical power meter and the switch are all electrically connected to the controller. The incident optical power meter is used to detect the optical signal intensity of the incident optical signal, and feed back the incident optical intensity detection signal to the controller. The reflected optical power meter is used to detect the optical signal intensity of the reflected optical signal, and feed back the reflected optical intensity detection signal to the controller; in this embodiment, the model of the reflected optical power meter is.

[0038] The controller controls the on and off of the switch according to the incident light intensity detection signal and the reflected light intensity detection signal. Specifically, the incident light intensity detection signal represents the power P of the incident light signal. 入射光 , the intensity detection signal of the reflected light indicates the power P of the reflected light signal 反射光 , usually the preset incident optical signal power P of the XGPON gateway 入射光The optical power of the incident light signal is 3dBm to 4dBm. After the incident light signal passes through the first splitter, the optical power is attenuated by 3.5dB. The attenuated incident light signal is transmitted to the three-ring polarizer, and a signal reflection is generated at the end of the total reflection optical fiber line. The reflected light power meter detects the optical signal strength of the reflected light signal in real time. The engineer checks the reflected light signal power P displayed by the reflected light power meter. 反射光 Adjust the parameters of the three-ring polarizer so that the adjusted P 反射光 Satisfies the following formula: |P 入射光 -P 反射光 |≤|incident optical power tolerance|, in this embodiment, the incident optical power tolerance is 12dB, that is, |P 入射光 -P 反射光 |≤12; Assume the incident light power P 入射光 =4dBm, then adjust the value of the optical attenuator so that the power value displayed by the optical power meter is greater than -8dBm. The controller analyzes the incident light intensity detection signal and the reflected light intensity detection signal. When the power of the reflected light signal satisfies the above formula, that is, when the incident light intensity detection signal and the reflected light intensity detection signal show that the absolute value of the difference between the incident light signal power and the reflected light signal power is less than 12dBm, the control switch is turned on, the first splitter is connected to the second splitter, and the first splitter transmits the reflected light signal to the second splitter.

[0039] The addition of an adjustable optical attenuator allows engineers to adjust the power of the optical signal as needed to simulate the impact of different reflected light intensities on the communication system. The three-ring polarizer further enriches the test conditions by adjusting the polarization direction of the optical signal to simulate the various polarization states that the optical signal may encounter in the actual network. During the test, engineers can adjust the parameters of the adjustable optical attenuator and the three-ring polarizer according to the reflected light intensity detection signal fed back by the reflected light power meter and the incident light intensity detection signal fed back by the incident light power meter, thereby adjusting the reflected light signal to meet the detection standards. Specifically, adjust the three rings of the three-ring polarization controller so that the polarization direction of the light reaches the desired state. The three rings control the polarization direction, polarization angle, and polarization intensity of the light respectively, and precise polarization direction control can be achieved through subtle adjustments.

[0040] like Figure 1 As shown, the optical oscilloscope and the spectrometer are both connected to the optical path of the second splitter. After the switch is turned on, the second splitter transmits the reflected light signal to the optical oscilloscope and the spectrometer respectively, and then the optical oscilloscope generates an eye diagram based on the reflected light signal; the spectrometer generates a spectrum based on the reflected light signal. Therefore, engineers can use the optical oscilloscope to observe whether the eye diagram of the reflected light is normal, such as the degradation range of the eye diagram margin value, the jitter degradation range, and other optical parameter indicators such as the optical power extinction ratio; and observe the laser light center wavelength offset range, SMSR, and 20dB bandwidth changes through the spectrum.

[0041] In actual testing, you can connect 10km or 20km to the first splitter to further simulate the actual application environment and check the degradation of optical parameter indicators. By recording the key test indicators after the above degradation, you can compare them with the test indicators of the incident optical signal to find out which optical parameter indicators have degraded after adding the reflected optical signal, which provides a basis for further evaluation of whether these degraded indicators affect the actual application of the project.

[0042] In summary, this solution can detect the anti-reflection light capability of the terminal to be tested, which is conducive to screening and eliminating unqualified terminals to be tested, ensuring product quality, and guaranteeing the network stability of the product and the user experience.

[0043] The above are only embodiments of the utility model. The common sense such as the known specific structures and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field of the utility model before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for the technicians in this field, without departing from the structure of the utility model, several deformations and improvements can be made, which should also be regarded as the protection scope of the utility model, which will not affect the effect of the implementation of the utility model and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to explain the content of the claims.

Claims

1. An anti-reflection light interference detection system for an optical network terminal, characterized in that: It includes a terminal to be tested, a first splitter, an adjustable optical attenuator, a three-ring polarizer, a total reflection optical fiber line, a second splitter, an optical oscilloscope and a spectrometer; The terminal to be tested, the adjustable optical attenuator and the second splitter are all connected to the optical path of the first splitter; the first splitter receives the incident optical signal of the terminal to be tested and transmits it to the adjustable optical attenuator; One end of the three-ring polarizer is connected to the optical path of the adjustable optical attenuator, and the other end is connected to the optical path of the total reflection optical fiber line; the incident light signal passes through the adjustable optical attenuator and the three-ring polarizer in sequence, is transmitted to the total reflection optical fiber line, and generates signal reflection through the total reflection optical fiber line to form a reflected light signal; the reflected light signal passes through the three-ring polarizer and the adjustable optical attenuator in sequence, and is fed back to the first splitter; the first splitter transmits the reflected light signal to the second splitter; The optical oscilloscope and the spectrometer are both connected to the optical path of the second splitter; the second splitter transmits the reflected light signal to the optical oscilloscope and the spectrometer respectively; the optical oscilloscope generates an eye diagram according to the reflected light signal; the spectrometer generates a spectrum diagram according to the reflected light signal.

2. The anti-reflection light interference detection system of the optical network terminal according to claim 1, characterized in that: It also includes a reflected light power meter connected to the optical path of the first splitter; the first splitter feeds back the received reflected light signal to the reflected light power meter; the reflected light power meter detects the optical signal intensity of the reflected light signal.

3. The anti-reflection light interference detection system of the optical network terminal according to claim 1, characterized in that: The first splitter is a 2:2 pull-hammer splitter.

4. The anti-reflection light interference detection system of the optical network terminal according to claim 3, characterized in that: The splitting ratio of the 2:2 pull-hammer splitter is 50:

50.

5. The anti-reflection light interference detection system of the optical network terminal according to claim 3, characterized in that: The wavelength range of the 2:2 pull-hammer splitter is 1260nm to 1650nm.

6. The anti-reflection light interference detection system of an optical network terminal according to claim 1, characterized in that: The total reflection optical fiber line is a UPC optical fiber connector, the input end of the UPC optical fiber connector is connected to the three-ring polarizer optical path, and the output end is provided with a reflection film to reflect the incident light signal to form a reflected light signal.

7. The anti-reflection light interference detection system of an optical network terminal according to claim 2, characterized in that: It also includes a controller and an incident optical power meter; a switch is provided between the first splitter and the second splitter; The incident optical power meter, the reflected optical power meter and the switch are all electrically connected to the controller; the incident optical power meter is also connected to the optical path of the terminal to be measured; The incident optical power meter detects the optical signal intensity of the incident optical signal and feeds back the incident optical intensity detection signal to the controller; The reflected light power meter detects the light signal intensity of the reflected light signal and feeds back the reflected light intensity detection signal to the controller; The controller controls the on and off of the switch according to the incident light intensity detection signal and the reflected light intensity detection signal.

8. The anti-reflection light interference detection system of an optical network terminal according to claim 1, characterized in that: The second splitter is a 1:2 splitter.

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