Method, system and equipment for monitoring optical cable of same optical fiber
By integrating OLS and OTDR functions into a single monitoring module, efficient, accurate, and economical optical cable monitoring is achieved, solving the problem of independent deployment of OTDR and OPM, simplifying the optical cable monitoring process, and improving monitoring efficiency and reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-24
- Publication Date
- 2026-03-13
AI Technical Summary
Existing optical cable monitoring equipment, OTDR and OPM, are deployed independently and require multiple optical fibers. Monitoring data cannot correspond to the same link. OTDR testing is time-consuming and costly, while OPM cannot identify the type and location of faults.
It integrates OLS and OTDR functions into a single monitoring module, outputs optical signals to N optical fibers through N output channels, receives and samples in parallel or time-division multiplexing, obtains optical power status in real time, and switches to OTDR mode for fault diagnosis.
It enables efficient and accurate fiber optic cable monitoring, reduces the number of devices and costs, simplifies wiring complexity, enables rapid fault response, and improves monitoring reliability and availability.
Smart Images
Figure CN121664290A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of optical cable testing technology, and in particular to a method, system and equipment for monitoring optical cables with the same optical fiber. Background Technology
[0002] In the field of optical cable construction, maintenance, and monitoring, the stable operation of optical fiber links relies on professional monitoring of key performance indicators such as attenuation, fault points, and loss distribution. However, current monitoring solutions still have significant technical bottlenecks, making it difficult to meet the application requirements of high efficiency, low cost, and high reliability. Currently, the monitoring equipment commonly used in the industry is mainly optical time-domain reflectometer (OTDR) and optical power monitor (OPM). Although both can achieve basic monitoring functions, their inherent defects have become key issues restricting the efficiency and practicality of optical cable monitoring.
[0003] OTDR, as a core diagnostic tool for optical cable monitoring, can generate characteristic curves by emitting laser pulses into the optical fiber and utilizing backscattering and reflection signals to perform tasks such as optical fiber attenuation measurement, fault location, and loss distribution monitoring. However, it has three unavoidable limitations: First, to ensure test accuracy, it is necessary to generate characteristic curves through multi-pulse transmission and data averaging, resulting in excessively long test times and failing to meet the requirements for rapid response. Second, because the backscattering signal in the optical fiber is extremely weak (e.g., the signal strength at a wavelength of 1550nm is only about -80dB / ns), it is necessary to rely on high-power lasers, high-performance photodetectors, and high-speed, low-noise analog amplifier circuits and other high-precision optoelectronic devices, which directly increases the equipment cost. Third, even if a single OTDR is expanded into a multi-link monitoring system through optical switches, each link still needs to be polled for testing, and the polling time increases significantly with the increase in the number of optical switch ports and the increase in test accuracy requirements, making it impossible to achieve real-time monitoring of the optical fiber network.
[0004] While OPM can achieve link status awareness by continuously monitoring changes in optical power (with a preset threshold triggering fault judgment), and its hardware consists of basic components such as photodetectors, transimpedance amplifiers (TIAs), and analog-to-digital converters (ADCs), it also has significant drawbacks: on the one hand, its monitoring function relies entirely on the light source at the other end of the fiber optic link, requiring the other end to emit optical signals to complete the monitoring, thus limiting its application scenarios; on the other hand, OPM can only identify the magnitude of changes in optical power loss, cannot determine the type of fault, and cannot locate the fault location, resulting in a single monitoring dimension and insufficient practicality.
[0005] To address the limitations of OTDR and OPM monitoring, a combination of OTDR and OPM (Optical Power Monitoring Unit) can be used to achieve status awareness and fault diagnosis of fiber optic links. However, in existing fiber optic cable monitoring networks, the deployment and operation of OTDR and OPM are completely independent, with incompatible control logic and workflows. They can only perform fault location and status detection separately, and require two independent optical fibers to monitor a single cable. This approach further amplifies technical shortcomings: from a construction and maintenance perspective, separate cabling and connections are required for both devices, increasing on-site construction workload and raising the risk of connection failures, resulting in high overall connection complexity; from a monitoring reliability perspective, if the fiber optic cable under monitoring contains multiple links or has branches, the OTDR and OPM are prone to monitoring different branches separately, leading to inconsistent data that cannot correspond to the actual operating status of the same fiber optic cable. This results in poor monitoring consistency and makes accurate monitoring impossible, severely limiting its application in large-scale, high-real-time fiber optic cable monitoring scenarios. Summary of the Invention
[0006] Therefore, the technical problem to be solved by the present invention is to overcome the high connection complexity of existing technologies, which require independent deployment of OTDR and OPM for optical cable monitoring and occupy multiple optical fibers, and the inconsistency of monitoring data from the two cannot correspond to the same link; at the same time, it solves the inherent shortcomings of OTDR testing, such as long testing time, high cost, and difficulty in real-time monitoring, as well as OPM, which depends on the light source at the other end and cannot identify the type and location of faults.
[0007] In a first aspect, to solve the above-mentioned technical problems, the present invention provides a method for monitoring optical cables with the same optical fiber, comprising: Configure a monitoring module and an OPM module; wherein, the monitoring module has two working modes: OLS working mode and OTDR working mode; the monitoring module has N output channels, and the OPM module has N input channels; When the OLS working mode is activated, optical signals for monitoring are output to N optical fibers through the N output channels, and the characteristics of the N optical fibers are monitored along the length of the optical fibers. The N input channels receive and sample the optical signals output from the N optical fibers; the N output channels are set to poll the transmission time of the optical signal once; based on the transmission time, the maximum signal received by each input channel within the transmission time is calculated, and the maximum signal is used as the received optical power of each input channel; Based on the received optical power, obtain the optical power detection results of each optical fiber link; according to the optical power detection results corresponding to each optical fiber link, determine whether the received optical power of each input channel of the OPM module has a sudden change and exceeds a set threshold; if not, no alarm is generated; if so, an alarm is generated, and the monitoring module is controlled to switch from the OLS working mode to the OTDR working mode; the OTDR working mode performs an OTDR test on the optical fiber connected to the corresponding channel to obtain the fault location and / or type of the current optical fiber.
[0008] In an embodiment of the present invention, the N input channels perform reception sampling on the optical signals output by the N optical fibers, where the reception sampling is parallel reception sampling or time-sharing reception sampling.
[0009] In an embodiment of the present invention, the parallel reception sampling is hardware parallel processing or logical parallel reception sampling; if the OPM module uses hardware parallel processing, set the sampling period of all input channels to T3, and the relational expression satisfied by the sampling period is T3 < T2; where, T2 represents the hold time after switching to the corresponding channel.
[0010] In an embodiment of the present invention, when the reception sampling is the time-sharing reception sampling, it includes: determining the initial physical port mapping relationship between the OPM module and the monitoring module, if the initial mapping relationship is disordered, then using the physical port of the monitoring module as a reference, allocating logical ports to the physical ports of the OPM module, so that the serial numbers of the logical ports correspond one-to-one with the physical ports of the monitoring module; the OPM module sequentially switches channels according to the serial numbers of the logical ports and receives the optical signals sent by the monitoring module.
[0011] In an embodiment of the present invention, when the reception sampling is the time-sharing reception sampling, it further includes comparing the channel switching time T1 of the monitoring module with the hold time T2 after switching to the corresponding channel; if T1 < T2, set the sampling period T of each channel of the OPM module to satisfy T ≤ T1 / 2; conversely, set the sampling period T of each channel of the OPM module to satisfy T ≤ T2 / 2.
[0012] In a second aspect, to solve the above technical problems, the present invention provides an optical cable monitoring system for the same optical fiber, including: A monitoring module, configured to start the OLS working mode to output optical signals for monitoring to N optical fibers through the N output channels, and perform feature monitoring on the N optical fibers along the optical fiber length direction; set the transmission time for the N output channels to poll the optical signals once. The OPM module is used to receive and sample the optical signals output from the N optical fibers through the N input channels; calculate the maximum signal received by each input channel during the transmission time based on the transmission time, and use the maximum signal as the received optical power of each input channel; and obtain the optical power detection result of each optical fiber link based on the received optical power. The server is used to determine, based on the optical power detection results corresponding to each optical fiber link, whether the received optical power of each input channel of the OPM module has changed abruptly and exceeded a set threshold. If not, no alarm is generated; if so, an alarm is generated, and the monitoring module is controlled to switch from the OLS working mode to the OTDR working mode. The OTDR working mode performs OTDR testing on the optical fiber connected to the corresponding channel to obtain the current fault location and / or type of the optical fiber.
[0013] In one embodiment of the present invention, a control module is further included, which is used to transmit the optical power detection results of each channel output by the OPM module to the server; the monitoring module includes an OTDR module and a 1:N optical switch, and the control module is connected to the OTDR module and the 1:N optical switch respectively; the OTDR module is connected to the 1:N optical switch.
[0014] In one embodiment of the present invention, the OTDR module includes a laser driver, a laser, a coupler, a photodetector, a transimpedance amplifier, and an analog-to-digital converter connected in sequence; wherein the laser driver and the analog-to-digital converter are both connected to the control module; and the coupler is connected to the 1:N optical switch.
[0015] In one embodiment of the present invention, a storage module is further included, which is connected to the OPM module; the OPM module compares the optical power detection result of each channel with the historical optical power value of the storage module to obtain the optical power change value; if the optical power change value exceeds a set threshold, the OPM module reports it to the server.
[0016] Thirdly, in order to solve the above-mentioned technical problems, the present invention provides an optical fiber cable monitoring device, including the above-mentioned optical fiber cable monitoring system.
[0017] Compared with the prior art, the above-described technical solution of the present invention has the following advantages: (1) The optical fiber monitoring method, system, and device described in this invention integrates OLS and OTDR functions into a single monitoring module, achieving efficient integration of the two monitoring tasks and reducing the required number of devices and costs. With the help of a polling mechanism, the monitoring module can efficiently monitor N optical fibers, ensuring that each fiber is fully tested, thereby significantly improving overall monitoring efficiency. During the monitoring process, the monitoring module outputs optical signals for monitoring to N optical fibers through N output channels and receives and samples the optical signals output from these optical fibers through N input channels. The system calculates the maximum signal received by each input channel during the transmission time, thereby obtaining the optical power status of each optical fiber in real time. This process not only ensures the accuracy and reliability of optical power detection but also provides a solid data foundation for subsequent fault diagnosis. When a sudden change in optical power is detected and exceeds a set threshold, the system will immediately trigger an alarm and quickly switch to OTDR working mode to perform detailed testing on the faulty optical fiber to accurately determine the location and type of the fault. This rapid response mechanism greatly shortens the fault handling time and improves the reliability and availability of the system.
[0018] (2) This invention requires only one optical fiber to complete the monitoring task, eliminating the need for multiple optical fibers to perform OPM and OTDR monitoring as in traditional methods. This not only simplifies the system architecture and reduces cabling complexity, but also provides a faster and more accurate reflection of the status of the monitored optical fiber and cable, offering a more efficient and accurate solution for optical cable maintenance and fault repair. Attached Figure Description
[0019] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.
[0020] Figure 1 This is a flowchart of a method for monitoring optical cables with the same optical fiber according to a preferred embodiment of the present invention; Figure 2 This is a timing diagram of the OLS and OPM working functions of a fiber optic cable monitoring method in a preferred embodiment of the present invention. Figure 3 This is a first structural diagram of a fiber optic cable monitoring system according to a preferred embodiment of the present invention; Figure 4 This is a schematic diagram showing the connection between the monitoring module, the OPM module, and the control module in a preferred embodiment of the present invention; Figure 5 This is a schematic diagram of the OTDR module structure in a preferred embodiment of the present invention; Figure 6 This is a second structural diagram of an optical fiber monitoring system according to a preferred embodiment of the present invention; Figure 7 This is a third structural diagram of an optical fiber monitoring system according to a preferred embodiment of the present invention. Detailed Implementation
[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.
[0022] Example 1: Reference Figure 1 As shown, this embodiment of the invention provides a method for monitoring optical cables with the same optical fiber, including but not limited to the following steps: Configure the monitoring module and the OPM module; the monitoring module has two working modes: OLS mode and OTDR mode; the monitoring module has N output channels and the OPM module has N input channels. When the OLS working mode is activated, optical signals for monitoring are output to N optical fibers through N output channels, and the characteristics of the N optical fibers are monitored along the length of the optical fibers. N input channels receive and sample the optical signals output from N optical fibers; the transmission time of the optical signals is set to poll the N output channels once; based on the transmission time, the maximum signal received by each input channel within the transmission time is calculated, and the maximum signal is used as the received optical power of each input channel; Based on the received optical power, the optical power detection result of each optical fiber link is obtained; based on the optical power detection result corresponding to each optical fiber link, it is determined whether the received optical power of each input channel of the OPM module has changed abruptly and exceeded the set threshold; if not, no alarm is generated; if so, an alarm is generated, and the monitoring module is controlled to switch from OLS working mode to OTDR working mode; the OTDR working mode performs OTDR test on the optical fiber connected to the corresponding channel to obtain the current fault location and / or type of the optical fiber.
[0023] This invention discloses a method for monitoring optical cables using the same optical fiber. By integrating both OLS and OTDR functions into a monitoring module, a single device can perform both monitoring tasks, thereby reducing the number of devices and costs. Utilizing a polling mechanism, the monitoring module can efficiently monitor N optical fibers, ensuring each fiber receives sufficient testing, thus significantly improving overall monitoring efficiency. During monitoring, the optical signals from the N optical fibers are received and sampled through N input channels, and the maximum signal received by each input channel during the transmission time is calculated, enabling real-time acquisition of the optical power status of each fiber. If a sudden change in optical power is detected exceeding a set threshold, an alarm is immediately generated, and the system quickly switches to OTDR mode for detailed testing of the faulty fiber to determine its location and type. This rapid response mechanism reduces fault handling time and improves the reliability and availability of the method. Furthermore, by calculating the maximum signal received by each input channel during the transmission time, this method ensures the accuracy and reliability of optical power detection. OTDR testing can accurately locate the fiber fault location and type, providing accurate information for fault repair and effectively reducing the possibility of misjudgment and missed detection. Compared with traditional methods, the method described in this embodiment of the invention no longer requires multiple optical fibers to perform OPM and OTDR monitoring separately. Only one optical fiber is needed to complete the monitoring, which can quickly and accurately reflect the status of the monitored optical fiber and cable. This avoids the high connection complexity of occupying multiple optical fibers and the inconsistency defect that the monitoring data of the two cannot correspond to the same link.
[0024] Specifically, the monitoring module has both integrated light source (OLS) and OTDR functions, and includes an OTDR module and an optical switch. In this embodiment of the invention, the optical switch is preferably a 1:N optical switch, which includes N output channels. The N output channels can output optical signals for monitoring by the OPM module to N optical fibers, and can also perform feature monitoring along the length of the N optical fibers.
[0025] Further, for the OTDR module of the monitoring module, it is used to implement the OTDR working mode and the OLS working mode. In the OTDR working mode, the specific execution steps of the monitoring module are as follows: control the 1:N optical switch module to switch to channel i, start the OTDR module test, the OTDR module emits optical pulses through the built-in laser detector, and the emitted optical pulses are output from the i-th channel (port) of the 1:N optical switch to the corresponding optical fiber in the optical cable. The signal returned from the optical fiber is received by the OTDR module after passing through the 1:N optical switch, and the OTDR curve is generated by demodulation. In the OLS working mode, the specific execution steps of the monitoring module are as follows: control the laser driver of the OTDR module to continuously drive the laser to emit light, and make the continuous optical signal emitted by the OTDR module output from each channel (port) of the 1:N optical switch in a time-sharing manner by controlling the 1:N optical switch. The preferred control method for channel switching in the embodiments of the present invention is: assuming that the switching time of the 1:N optical switch is T1, and the holding time of each channel is set to T2, so the channel interval time is T1 + T2. <0oo0087>Specifically, for the OPM module (optical power measurement module), it includes N input channels, and the N input channels can receive and sample the signals output by N photodetectors in parallel. Among them, the reception sampling is preferably parallel reception sampling or time-sharing reception sampling.
[0027] Specifically, for parallel reception sampling, it can be hardware parallel processing or logical parallel reception sampling. If hardware parallel processing is adopted, each input channel of the OPM module includes a receiving circuit, an analog-to-digital converter (ADC) or an analog-to-digital converter channel, and can measure the optical signals on N channels at the same time. When the OPM module adopts hardware parallel reception, the sampling period of all input channels is set to T3, and the relational expression satisfied by the sampling period is T3 < T2. Where, T2 represents the holding time after the optical switch switches to the corresponding channel. In addition, the corresponding timing relationship between the OLS transmission of N channels and the parallel reception of N channels of the OPM in the monitoring module can be referred to Figure 2 as shown.
[0028] Further, if the logical parallel reception sampling method is adopted, for example, within the transmission time slot of each channel of the OLS (that is, within the residence time after the optical switch switches to this channel), the OPM module can complete 1 reception sampling of N channels in a time-sharing manner. That is to say, within each transmission time slot, the OPM module can complete the operations of N optical power monitoring time slots.
[0029] It should be noted that there is a misspelling in the original text of , it should be "
[0026] " instead of "<0oo0087>". The above translation has been corrected accordingly.Specifically, when the received sampling is time-division multiplexing, the N receiving channels in the OPM module share a single analog receiving circuit and / or ADC. During testing, these channels will switch in a time-division manner to connect to the corresponding photodetector to receive the optical signal of that channel. Furthermore, for time-division multiplexing, there are three cases: Case 1, Case 2, and Case 3, as detailed below: In the first scenario, a multi-channel OPM module (i.e., N input channels) is connected to only one monitoring module at the other end; In the second scenario, a multi-channel OPM module is connected to multiple monitoring modules at one end. In the third scenario, multiple multi-channel OPM modules are randomly connected to multiple monitoring modules.
[0030] Furthermore, in the first scenario, before the OPM module's receiving sampling becomes time-division multiplexing, the following steps are taken: determining the initial mapping relationship between the physical ports of the OPM module and the monitoring module. If the initial mapping relationship is out of order, the physical ports of the monitoring module are used as a reference to allocate logical ports to the physical ports of the OPM module, ensuring a one-to-one correspondence between the logical port numbers and the physical ports of the monitoring module. When the OLS of the monitoring module switches ports to send optical signals according to the physical port numbers, the OPM module switches channels sequentially according to the logical port numbers and receives the optical signals sent by the monitoring module, thereby achieving real-time monitoring of the performance of the connected fiber optic link. In addition, the mapping relationship can be calculated by a server. After the calculation is completed, the result is transmitted to the monitoring module and the OPM module via the network to ensure that each module operates according to the accurate mapping relationship.
[0031] For example, assume the four physical ports are associated as {[1,3];[2,4];[3,1],[4,2]}, where [1,3] indicates that physical port 1 of the OLS is connected to physical port 3 of the OPM module. Referring to the OLS physical port number, after assigning a logical port to the OPM module, the OPM module receives samples in a time-division multiplexing order (3,4,1,2). Similarly, if the OPM module's physical port is used as a reference, another logical port can be assigned to the OLS physical port, with the logical port number matching the OPM physical port order. During OLS transmission, the logical port number is used to sequentially transmit optical signals through each channel.
[0032] Furthermore, in the second scenario, before the OPM module's receiving sampling becomes time-division multiplexing, the following steps are taken: using the physical port of the OPM module as a reference, logical ports are allocated to the OLS ports of multiple monitoring modules, allowing the OLS ports of the multiple monitoring modules to sequentially send OLS test optical signals according to the order of the OPM module's physical ports. The OPM module receives the sampling optical signal from each physical port in a time-division multiplexing manner and measures the optical power of the corresponding fiber optic link.
[0033] Further, in the third case, assume that the j-th OLS port of the i-th monitoring module is connected to the m-th port of the k-th OPM module, which can be expressed as {O i T j ,P k R m}. Based on this connection relationship, construct a bipartite graph and perform matching through algorithms (such as the Hungarian Algorithm, Hopcroft-Karp algorithm, maximum-flow-based algorithm, greedy matching algorithm). Finally, generate the sender-side mapping function sender_map[i][j] on the OLS side and the receiver-side mapping function receiver_map[k][m] on the OPM module side, ensuring that the corresponding values of the two are equal. In this way, both the sending and receiving operations can be carried out according to the new mapping logic port order, thus achieving efficient and accurate data transmission.
[0034] Further, when the OPM module performs time-sharing reception and sampling, it also includes comparing the channel switching time T1 on the OLS side of the monitoring module with the holding time T2 after switching to the corresponding channel; if T1 < T2, set the sampling period T of each channel of the OPM module to satisfy T ≤ T1 / 2; otherwise, set the sampling period T of each channel of the OPM module to satisfy T ≤ T2 / 2. This design enables each channel of the OPM module to collect the signals on the optical fiber line during the channel switching period; within the holding time of each channel, at least two optical power values can also be collected. By analyzing the acquisition results during the channel switching period and the channel holding time, it can be judged whether the acquisition window of each channel of the OPM module is aligned with the sending window of each channel of the OLS. If aligned, the test data envelope of each channel of the OPM module will present an ascending edge and a descending edge, and the two are basically the same. If it is found that the ascending edge becomes fewer, it indicates that the time slot allocated to this channel lags and needs to be adjusted forward; if the descending edge decreases and the ascending edge becomes wider, it means that the time slot of this channel of the OPM is ahead and needs to be adjusted backward.
[0035] Specifically, in the embodiment of the present invention, set the time for the N channels on the OLS side of the monitoring module to poll and send an optical signal once as N*(T1 + T2), where T1 is the time for the optical switch to switch, then the OPM module calculates the maximum signal received by each input channel within the time of N*(T1 + T2), and takes the maximum signal as the received optical power of each input channel.
[0036] Specifically, the principle of obtaining the optical power detection result for each optical fiber link based on the received optical power is that each receiving channel corresponds to a specific optical fiber link (the transmission path is: output channel, optical fiber, input channel), and this link is susceptible to transmission failure. Under normal operating conditions, it is assumed that the optical power of the OLS remains constant. Based on this premise, when an abnormal change in the received optical power of a certain receiving channel is detected, it can be determined that an abnormal change has occurred in the optical fiber link corresponding to that channel.
[0037] Specifically, after the OPM module receives the optical power detection results for each channel, it transmits them to the server in real time via the network (e.g., twice per second). The server stores and records the link loss from the OLS to the OPM or the optical power value monitored by the OPM module. If a sudden change is detected in the link loss of a channel or the optical power received by the OPM (the change in link loss or received optical power exceeds a set threshold), an alarm is generated. Simultaneously, the server sends a command to the monitoring module to stop transmitting OLS optical signals and switch it from OLS operating mode to OTDR operating mode. In OTDR mode, OTDR testing is performed on the optical fiber connected to the corresponding channel to determine the fault location and / or type of the connected optical fiber. The OTDR testing process for the optical fiber connected to the corresponding channel in OTDR mode is as follows: The OTDR module emits an optical pulse, which is output to the optical fiber in the corresponding optical cable through the channel corresponding to the optical switch. The signal reflected back from the optical fiber is transmitted back to the OTDR module via the optical switch, where it is demodulated to generate an OTDR curve. The location and / or type of optical fiber fault are then determined based on the OTDR curve.
[0038] Optionally, after acquiring the optical power detection results for each receiving channel, the OPM module can periodically transmit the results to the server via the network (e.g., every 10 seconds). Simultaneously, the OPM module can also compare the detected optical power value with the historical optical power values of that channel stored locally. If the received optical power value change exceeds a set threshold, it will immediately report it to the server via the network. Upon receiving the alarm from the OPM module indicating that the optical power value change exceeds the set threshold, the server will send a command to the monitoring module integrating OLS and OTDR functions to stop transmitting OLS optical signals and switch from OLS operating mode to OTDR operating mode. Subsequently, the monitoring module will initiate OTDR operating mode to perform OTDR testing on the optical fiber connected to the corresponding channel to determine the location and / or type of fiber fault.
[0039] The optical cable monitoring method described in this invention optimizes the existing technology where OTDR and OPM need to be deployed independently, each occupying multiple optical fibers. This traditional deployment method not only leads to high connection complexity but also makes it difficult to map the monitoring data of OTDR and OPM to the same link, resulting in inconsistencies. Furthermore, OTDR testing is time-consuming, costly, and difficult to achieve real-time monitoring; while OPM relies on the light source at the other end and cannot identify the fault type and location. This method, through the above design, overcomes these shortcomings of the prior art, providing a more efficient, economical, and functionally integrated optical cable monitoring solution.
[0040] Example 2: Based on the same inventive concept, this embodiment provides a fiber optic cable monitoring system. The principle of solving the problem is similar to that of the fiber optic cable monitoring method provided in Embodiment 1, and the repeated parts will not be described again.
[0041] Reference Figure 3 As shown, this embodiment provides an optical fiber cable monitoring system, including: The monitoring module is used to start the OLS working mode and output optical signals for monitoring to N optical fibers through N output channels, and to perform characteristic monitoring of N optical fibers along the fiber length; the transmission time of the optical signal is set by polling the N output channels once. The OPM module is used to receive and sample the optical signals output from N optical fibers through N input channels; it calculates the maximum signal received by each input channel during the transmission time based on the transmission time, and uses the maximum signal as the received optical power of each input channel; based on the received optical power, it obtains the optical power detection result of each optical fiber link. The server is used to determine whether the received optical power of each input channel of the OPM module has changed abruptly and exceeded the set threshold based on the optical power detection results corresponding to each optical fiber link. If not, no alarm is generated; if so, an alarm is generated and the monitoring module is controlled to switch from OLS working mode to OTDR working mode. In OTDR working mode, the optical fiber connected to the corresponding channel is tested by OTDR to obtain the current fault location and / or type of the optical fiber.
[0042] Specifically, refer to Figure 3 As shown, the monitoring module has N output terminals, and the OPM module has N input terminals. At least one optical cable connects the monitoring module and the OPM module for detecting optical cables. The N output terminals of the monitoring module are connected to the N input terminals of the OPM module via this optical cable. This design allows the optical cable monitoring system to simultaneously implement OTDR and OLS functions using only a single output optical fiber.
[0043] Specifically, refer to Figure 4As shown, the optical cable monitoring system provided in this embodiment also includes a control module for transmitting the optical power detection results of each channel output by the OPM module to the server; the monitoring module includes an OTDR module and a 1:N optical switch. The control module is connected to both the OTDR module and the 1:N optical switch; the OTDR module is connected to the 1:N optical switch.
[0044] Specifically, an OTDR module includes a laser driver, a laser, a coupler, a photodetector, a transimpedance amplifier, and an analog-to-digital converter connected in sequence, such as... Figure 5 As shown in the diagram. The laser driver and analog-to-digital converter are both connected to the control module; the coupler is connected to the 1:N optical switch.
[0045] Furthermore, the monitoring module works as follows: In OTDR mode, the control module controls the 1:N optical switch module to switch to channel i, initiating OTDR module testing. The OTDR module emits light pulses through its built-in laser detector. These pulses are output from the i-th channel (port) of the 1:N optical switch to the corresponding optical fiber in the optical cable. The signal returning from the optical fiber is received by the OTDR module after passing through the 1:N optical switch, and demodulated to generate an OTDR curve. In OLS mode, the control module controls the laser driver of the OTDR module to continuously drive the laser to emit light. The control module controls the 1:N optical switch to output the continuous optical signal emitted by the OTDR module from each channel (port) of the 1:N optical switch in a time-division manner. The preferred control method for this system is as follows: assuming the 1:N optical switch switching time is T1, and the hold time for each channel is set to T2, the channel interval time is T1 + T2.
[0046] The OTDR module described in this embodiment of the invention performs OTDR functions while also implementing OLS functions through its built-in laser, significantly improving integration. Furthermore, since no additional light source is required, the overall size of the device is greatly reduced, thereby optimizing space utilization and portability.
[0047] Specifically, refer to Figure 3 As shown, the OPM module comprises N parallel branches connected in sequence. Each branch includes a photodetector PD (such as PD1, PD2, PDN, etc.), a receiving circuit, and a sampling circuit. The receiving circuit includes a current-to-voltage amplifier circuit (such as a transimpedance amplifier circuit), and a voltage amplifier circuit can be selected according to requirements. The core function of the current-to-voltage amplifier circuit is to convert the weak photocurrent output by the photodetector PD into a processable voltage signal and perform preliminary amplification. The sampling circuit includes a sample-and-hold circuit and an analog-to-digital converter circuit. Its function is to sample and hold the analog voltage signal output by the receiving circuit, and finally achieve digital quantization through analog-to-digital conversion, outputting a digital signal that can be used for subsequent processing.
[0048] Specifically, refer to Figure 5 As shown, the optical cable monitoring system provided in this embodiment also includes a storage module, which can be connected to the control module or the OPM module. The OPM module compares the optical power detection result of each channel with the historical optical power value of the storage module to obtain the optical power change value. If the optical power change value exceeds the set threshold, the OPM module reports it to the server.
[0049] Specifically, the server is also connected to terminal devices, which can be either web-based or mobile apps. Users can obtain real-time fiber optic monitoring data, alarm notifications, and OTDR fault analysis results transmitted by the server through the terminal, further expanding the channels for obtaining monitoring information and improving the ease of use.
[0050] It should be noted that, in the embodiments of this invention, the monitoring module can be assembled separately into a comprehensive monitoring device integrating OLS and OTDR functions. The OPM module, control module, and / or storage module are assembled into an integrated OPM device, such as... Figure 3 As shown. Therefore, the optical cable monitoring system includes integrated monitoring equipment, OPM equipment, and a server. The above-described optical cable monitoring system is the first structure provided in this embodiment. In addition, this embodiment also provides second and third structures of optical cable monitoring systems.
[0051] Specifically, refer to Figure 6 As shown, in the second type of optical cable monitoring system, the monitoring module further includes an OPM module with OPM function. The OPM module is built into the monitoring module and connected to the control module. The second type of optical cable monitoring system includes a first monitoring module and a second monitoring module, which are located at both ends of the optical cable and have OTDR, OLS, and OPM functions. Figure 6 The working principle of the optical cable monitoring system is as follows: The first monitoring module connects the OTDR module, which implements both OTDR and OLS functions, to the OPM module of the second monitoring module via a 1:N optical switch and an optical fiber in the optical cable, thereby monitoring the connected optical fiber link. The second monitoring module connects the OTDR module, which implements both OTDR and OLS functions, to the OPM module of the first monitoring module via a 1:N optical switch and an optical fiber in the optical cable, thereby monitoring the connected optical fiber link.
[0052] Furthermore, for the second type of optical cable monitoring system, its monitoring module and control module can be combined to form an integrated monitoring device that integrates OLS, OTDR, and OPM functions. In this case, the second type of optical cable monitoring system includes a server and at least two integrated monitoring devices.
[0053] The monitoring module described in this embodiment includes two forms: one is a monitoring module with OTDR and OLS functions, and the other is a monitoring module with OTDR, OLS and OPM functions. Both forms of monitoring modules can effectively reduce equipment size, reduce equipment cost, occupy less computer room space, and facilitate large-scale deployment.
[0054] Specifically, refer to Figure 7 As shown, the third type of optical cable monitoring system includes multiple sites to be tested. Each site includes a comprehensive monitoring device with OTDR, OLS, and OPM functions (the same as the comprehensive monitoring device in the second type of system). The comprehensive monitoring devices of adjacent sites are connected to form a chain monitoring topology to monitor the connected optical fiber links; or the comprehensive monitoring devices of adjacent sites are connected, and the comprehensive monitoring devices of the head and tail sites are connected to form a ring monitoring topology to monitor the connected optical fiber links.
[0055] For example, the first site (e.g.) Figure 7 The fiber optic link connecting the OTDR and OLS functions of the integrated monitoring equipment at station A in the middle to the second station (e.g., Figure 7 The OPM function of the integrated monitoring equipment at the second site (B station) is connected to monitor the connected fiber optic links. The OTDR and OLS functions of the integrated monitoring equipment at the second site are connected to the fiber optic links of the third site (e.g., B station). Figure 7 The monitoring equipment at station C in the first site is connected to the OPM function of the integrated monitoring device to monitor the connected fiber optic links. This process is repeated to form a chain-like monitoring topology. The integrated monitoring equipment at different stations is connected to the server via a network. Alternatively, the fiber optic links connected to the OTDR and OLS functions of the integrated monitoring equipment at the third station can be connected to the OPM function of the integrated monitoring equipment at the first station to monitor the connected fiber optic links, thus forming a ring-like monitoring topology. The monitoring process under this structure is similar to that of the fiber optic cable monitoring system in the first structure and will not be described further here.
[0056] Example 3: This embodiment provides a fiber optic cable monitoring device, including the fiber optic cable monitoring system provided in Embodiment 2.
[0057] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.
[0058] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.
[0059] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.
[0060] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.
[0061] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.
Claims
1. A method for monitoring optical cables with the same optical fiber, characterized in that, Comprising: A configuration monitoring module and an OPM module; wherein, the working modes of the monitoring module include an OLS working mode and an OTDR working mode; the monitoring module includes N output channels, and the OPM module includes N input channels; When starting the OLS working mode, an optical signal for monitoring is output to N optical fibers through the N output channels, and characteristic monitoring of the N optical fibers is performed along the fiber length direction; The N input channels perform reception sampling on the optical signals output by the N optical fibers; set the transmission time of the optical signal to be polled once by the N output channels; according to the transmission time, calculate the maximum signal received by each input channel within the transmission time, and use the maximum signal as the received optical power of each input channel; According to the received optical power, obtain the optical power detection result of each optical fiber link; according to the optical power detection result corresponding to each optical fiber link, determine whether the received optical power of each input channel of the OPM module has a sudden change and exceeds a set threshold; if not, no alarm is generated; if so, an alarm is generated, and the monitoring module is controlled to switch from the OLS working mode to the OTDR working mode; the OTDR working mode performs an OTDR test on the optical fiber connected to the corresponding channel to obtain the fault position and / or type of the current optical fiber.
2. The optical cable monitoring method according to claim 1, characterized in that, The N input channels perform reception sampling on the optical signals output by the N optical fibers, where the reception sampling is parallel reception sampling or time-sharing reception sampling.
3. The optical cable monitoring method according to claim 2, characterized in that, The parallel reception sampling is hardware parallel processing or logical parallel reception sampling; if the OPM module uses hardware parallel processing, set the sampling period of all input channels to T3, and the relational expression satisfied by the sampling period is T3 < T2; where, T2 represents the holding time after switching to the corresponding channel.
4. The optical cable monitoring method according to claim 2, characterized in that, When the reception sampling is the time-sharing reception sampling, it includes: determining the initial physical port mapping relationship between the OPM module and the monitoring module, if the initial mapping relationship is disordered, then using the physical port of the monitoring module as a reference, assigning logical ports to the physical ports of the OPM module, so that the serial numbers of the logical ports correspond one-to-one with the physical ports of the monitoring module; the OPM module sequentially switches channels according to the serial numbers of the logical ports and receives the optical signals sent by the monitoring module.
5. A method for monitoring optical cables with the same optical fiber as described in claim 2 or 4, characterized in that, When the reception sampling is the time-sharing reception sampling, it also includes comparing the channel switching time T1 of the monitoring module with the holding time T2 after switching to the corresponding channel; if T1 < T2, set the sampling period T of each channel of the OPM module to satisfy T ≤ T1 / 2; otherwise, set the sampling period T of each channel of the OPM module to satisfy T ≤ T2 / 2.
6. A fiber optic cable monitoring system, used to implement the fiber optic cable monitoring method according to any one of claims 1 to 5, characterized in that, Comprising: A monitoring module, configured to start the OLS working mode to output an optical signal for monitoring to N optical fibers through the N output channels, and perform characteristic monitoring of the N optical fibers along the fiber length direction; Set the transmission time of the optical signal to be polled once by the N output channels; The OPM module is used to receive and sample the optical signals output from the N optical fibers through the N input channels. Based on the transmission time, calculate the maximum signal received by each input channel during the transmission time, and use the maximum signal as the received optical power of each input channel; Based on the received optical power, the optical power detection result of each optical fiber link is obtained; The server is used to determine, based on the optical power detection results corresponding to each optical fiber link, whether the received optical power of each input channel of the OPM module has changed abruptly and exceeded a set threshold. If not, no alarm is generated; if so, an alarm is generated, and the monitoring module is controlled to switch from the OLS working mode to the OTDR working mode. The OTDR working mode performs OTDR testing on the optical fiber connected to the corresponding channel to obtain the current fault location and / or type of the optical fiber.
7. The optical fiber cable monitoring system according to claim 6, characterized in that, It also includes a control module for transmitting the optical power detection results of each channel output by the OPM module to the server; the monitoring module includes an OTDR module and a 1:N optical switch, and the control module is connected to the OTDR module and the 1:N optical switch respectively; the OTDR module is connected to the 1:N optical switch.
8. The optical fiber cable monitoring system according to claim 7, characterized in that, The OTDR module includes a laser driver, a laser, a coupler, a photodetector, a transimpedance amplifier, and an analog-to-digital converter connected in sequence. The laser driver and the analog-to-digital converter are both connected to the control module; the coupler is connected to the 1:N optical switch.
9. The optical fiber cable monitoring system according to claim 6, characterized in that, It also includes a storage module connected to the OPM module; the OPM module compares the optical power detection result of each channel with the historical optical power value of the storage module to obtain the optical power change value; if the optical power change value exceeds a set threshold, the OPM module reports it to the server.
10. A fiber optic cable monitoring device, characterized in that, Includes the optical fiber cable monitoring system according to any one of claims 6 to 9.