Method for solving alarm oscillation based on secondary analysis

Abstract

The invention provides a method for solving alarm oscillation based on secondary analysis, relates to the field of optical cable monitoring and is applied to an optical time domain reflectometer module in optical cable monitoring, and the method comprises the following steps: based on the optical time domain reflectometer module, judging whether an alarm is changed through a secondary analysis algorithm; the optical time domain reflectometer module is configured with a standard curve; the standard curve represents the initial state of the to-be-tested line and comprises test parameters for performing OTDR test on the to-be-tested line and a threshold value of optical cable line alarm; calculating the loss variation of the optical fiber line in the to-be-detected line, and judging the state (alarm level) of the optical fiber line according to an alarm threshold value; and when the to-be-detected line gives an alarm, carrying out secondary analysis on the historical alarm to determine whether the historical alarm disappears or not. According to the method, through secondary analysis of historical alarms, repeated alarms caused by line loss fluctuation due to circuit noise, laser output power fluctuation and calculation precision are avoided, and the accuracy of optical fiber line fault positioning can be improved.

Description

Technical Field

[0001] The present invention relates to the field of optical cable monitoring, and particularly to a method for solving alarm oscillation based on secondary analysis. Background Art

[0002] When laser transmits in an optical fiber, Rayleigh scattering and Fresnel reflection will occur. The OTDR technology obtains the attenuation of the optical fiber line and the link connection status by detecting Rayleigh scattering and Fresnel reflection. In an optical cable monitoring system, the OTDR technology is used to monitor the optical cable line. Generally, the initial state of the line is obtained through an OTDR test at the beginning of the opening of the optical fiber line. The alarm threshold is set according to the influence degree of the loss increment caused by the deterioration of the optical fiber on its service. The OTDR curve representing the initial state of the optical fiber line and the alarm threshold are saved in the device, and then the line is cyclically tested with the same parameters. The test result is compared with the standard curve. When the line loss increment exceeds the alarm threshold, an alarm is generated.

[0003] In a traditional optical cable monitoring system, only by analyzing the previous test results in combination with the standard curve, the change amount of the loss of the optical fiber line is judged. When it exceeds the alarm threshold of the corresponding level, an alarm of the corresponding level is generated. When it is lower than this threshold, the alarm level is adjusted accordingly. Due to the influence of the output power fluctuation of the laser, the receiver noise, and the calculation accuracy, the calculated value of the line loss fluctuates within a certain range. When the loss of a certain line is just near the alarm threshold, using the above method will cause the alarms reported by the optical cable monitoring device to change repeatedly, that is, alarm oscillation. Summary of the Invention

[0004] In order to overcome the deficiencies of the prior art, the purpose of the present invention is to provide a method for solving alarm oscillation based on secondary analysis. By performing secondary analysis on historical alarms, the problem of repeated changes in the optical fiber line alarm caused by the fluctuation of the loss increment of the optical fiber line near the alarm threshold due to the influence of the output power fluctuation of the laser, the receiver noise, and the calculation accuracy, that is, alarm oscillation, is effectively solved.

[0005] To achieve the above purpose, the present invention provides the following solution:

[0006] A method for solving alarm oscillation based on secondary analysis, comprising:

[0007] S1: Use an optical time domain reflectometer module to test the monitored line, and store the test result and the alarm threshold as a standard curve in the optical time domain reflectometer module; the standard curve is used to represent the initial state of the line to be tested; the standard curve includes the test parameters for testing the monitored line and the alarm threshold of the monitored line;

[0008] S2: Use the test results and the alarm threshold values saved by the optical time domain reflectometer module to perform cyclic tests on the monitored line, and obtain test results; the test results include the loss of events and the fiber length.

[0009] S3: Calculate the change in the line loss of the current line and the line loss of the standard curve.

[0010] S4: Determine whether there is an alarm based on the change in line loss and the corresponding alarm threshold value. If so, classify the alarm levels into Level 1 alarm, Level 2 alarm, Level 3 alarm, and Level 4 alarm according to the severity; the fourth-level alarm represents no alarm.

[0011] S5: If the current alarm level is 4 and the historical alarm is empty, jump to step S2.

[0012] S6: If the current alarm level is 4 and there is a historical alarm, start the secondary analysis algorithm. If the current alarm is true and valid, that is, the alarm disappears, mark the current alarm as disappeared, clear the historical alarm, and jump to step S2.

[0013] S7: If the alarm level of the current alarm is not 4 and the historical alarm is empty, record the current alarm in the historical alarm, and at the same time mark it as an alarm generated, and jump to step S2.

[0014] S8: Check whether the current alarm is the same as the historical alarm.

[0015] S9: If so, determine the current alarm as a repeated alarm, and jump to step S2.

[0016] S10: If not, start the secondary analysis algorithm. If the current alarm is true and valid, mark the current alarm as a new alarm, and at the same time overwrite and save the current alarm to the historical alarm, and jump to step S2; if the current alarm is invalid, directly jump to step S2.

[0017] Preferably, in step S8, the judgment criterion for the current alarm to be the same as the historical alarm is:

[0018] The alarm location and level are equal at the same time to be the same.

[0019] Preferably, when the location of the historical alarm is different from the location of the current alarm, the steps of the secondary analysis algorithm include:

[0020] Judge whether the level of the historical alarm is adjacent to the level of the current alarm.

[0021] If the level of the historical alarm is not adjacent to the level of the current alarm, then judge that the current alarm is true and valid, end the execution, and return the judgment result.

[0022] Determine the event point of the location of the historical alarm on the current OTDR curve;

[0023] If the event point does not exist, determine that the current alarm is real and effective, end the execution, and return the judgment result;

[0024] If the event point exists, adjust the alarm threshold downward, and re-determine the alarm level corresponding to the loss change amount of the event. If the level of the new alarm is the same as the historical alarm level, determine that the current alarm is a false alarm; otherwise, determine that the current alarm is real and effective, end the execution, and return the judgment result.

[0025] Preferably, when the alarm location of the current alarm is the same as that of the historical alarm, but the alarm levels are different, the process of the secondary analysis algorithm includes:

[0026] Determine whether the levels of the historical alarm and the current alarm are adjacent;

[0027] If the level of the historical alarm is not adjacent to that of the current alarm, determine that the current alarm is real and effective, end the execution, and return the judgment result;

[0028] When the level of the historical alarm is adjacent to that of the current alarm, and the severity of the historical alarm is lower than that of the current alarm, adjust the alarm threshold upward; otherwise, adjust the alarm threshold downward;

[0029] Use the new alarm threshold to re-determine the current alarm level. If the alarm level is the same as the historical alarm level, determine that the current alarm is invalid; otherwise, the current alarm is valid.

[0030] Preferably, the judgment criterion for whether the levels of the historical alarm and the current alarm are adjacent is:

[0031] The absolute value of the difference between the levels of the historical alarm and the current alarm is 1 for being adjacent.

[0032] Preferably, the steps for adjusting the amplitude of the alarm threshold include:

[0033] Determine whether the line loss amount exceeds the alarm threshold. If it does not exceed the alarm threshold, record the line loss amount.

[0034] When the accumulated number of recorded line loss amounts reaches the preset number of times, calculate the maximum and minimum values of the recorded line loss amounts, and find the difference between the maximum and minimum values;

[0035] Take twice the difference as the amplitude of the upward or downward floating of the alarm threshold, and save the amplitude to the optical time domain reflectometer module.

[0036] Preferably, the preset number of times is not less than 256 times.

[0037] Preferably, when the cumulative amount of recorded line loss has not reached the preset number of times, 30% of the alarm threshold is used as the amplitude of alarm floating up or down, and the amplitude is saved in the optical time domain reflectometer module.

[0038] According to the specific embodiments provided by the present invention, the following technical effects are disclosed by the present invention:

[0039] The present invention provides a method for solving alarm oscillation based on secondary analysis, including: S1: Using an optical time domain reflectometer module to test a monitored line, and storing the test result and the alarm threshold as a standard curve in the optical time domain reflectometer module; the standard curve is used to characterize the initial state of the line to be tested; the standard curve includes the test parameters for testing the monitored line and the alarm threshold of the monitored line; S2: Using the test result and the alarm threshold saved by the optical time domain reflectometer module to perform a cyclic test on the monitored line, and obtaining a test result; the test result includes the loss of the event and the optical fiber length; S3: Calculating the change amount of the current line loss and the line loss of the standard curve; S4: Determining whether there is an alarm according to the change amount of the line loss and the corresponding alarm threshold. If so, the alarm levels are divided into level 1 alarm, level 2 alarm, level 3 alarm and level 4 alarm according to the severity; the level 4 alarm represents no alarm; S5: If the current alarm level is 4 and the historical alarm is empty, jump to step S2; S6: If the current alarm level is 4 and the historical alarm exists, start the secondary analysis algorithm. If the current alarm is true and valid, that is, the alarm disappears, mark the current alarm as disappeared, clear the historical alarm, and jump to step S2; S7: If the current alarm level is not 4 and the historical alarm is empty, record the current alarm in the historical alarm, and mark it as an alarm generated at the same time, and jump to step S2; S8: Check whether the current alarm is the same as the historical alarm; S9: If so, determine the current alarm as a repeated alarm, and jump to step S2; S10: If not, start the secondary analysis algorithm. If the current alarm is true and valid, mark the current alarm as a new alarm, and at the same time overwrite and save the current alarm to the historical alarm, and jump to step S2; if the current alarm is invalid, directly jump to step S2. By performing secondary analysis on historical alarms, the present invention avoids repeated changes in alarms caused by circuit noise, laser output power fluctuations, and line loss fluctuations caused by calculation accuracy, and can improve the accuracy of optical fiber line fault location. Description of the Drawings

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0041] Figure 1 This is the flowchart of the method provided by the embodiment of the present invention;

[0042] Figure 2 This is the schematic diagram of the technical route provided by the embodiment of the present invention;

[0043] Figure 3 This is the flowchart of the steps with different alarm positions of the secondary analysis algorithm provided by the embodiment of the present invention;

[0044] Figure 4 This is the schematic diagram of the steps with the same alarm position but different alarm levels of the secondary analysis algorithm provided by the embodiment of the present invention.

[0045] Figure 5 This is the schematic diagram for confirming the floating range of the alarm threshold of the secondary analysis algorithm provided by the embodiment of the present invention. Detailed implementation manners

[0046] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0047] The purpose of the present invention is to provide a method for solving alarm oscillation based on secondary analysis. Through secondary analysis of historical alarms, it is possible to avoid repeated changes in alarms caused by circuit noise, fluctuations in laser output power, and fluctuations in line losses caused by calculation accuracy, and improve the accuracy of fiber optic line fault location.

[0048] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0049] Figure 1 This is the flowchart of the method provided by the embodiment of the present invention. As Figure 1 shown, the present invention provides a method for solving alarm oscillation based on secondary analysis, including:

[0050] S1: Use an optical time domain reflectometer module to test the monitored line, and store the test result and the alarm threshold as a standard curve in the optical time domain reflectometer module; the standard curve is used to characterize the initial state of the line to be tested; the standard curve includes the test parameters for testing the monitored line and the alarm threshold of the monitored line;

[0051] S2: Use the test results and the alarm threshold values saved in the optical time domain reflectometer module to perform cyclic tests on the monitored line, and obtain test results; the test results include the loss of the event and the optical fiber length.

[0052] S3: Calculate the change in the line loss between the current line loss and the line loss of the standard curve.

[0053] S4: Determine whether there is an alarm based on the change in line loss and the corresponding alarm threshold value. If so, classify the alarm levels into level 1 alarm, level 2 alarm, level 3 alarm, and level 4 alarm according to the severity; the level 4 alarm represents no alarm.

[0054] S5: If the current alarm level is 4 and the historical alarm is empty, jump to step S2.

[0055] S6: If the current alarm level is 4 and there is a historical alarm, start the secondary analysis algorithm. If the current alarm is truly valid, that is, the alarm disappears, mark the current alarm as disappeared, clear the historical alarm, and jump to step S2.

[0056] S7: If the alarm level of the current alarm is not 4 and the historical alarm is empty, record the current alarm in the historical alarm, and at the same time mark it as an alarm generated, and jump to step S2.

[0057] S8: Check whether the current alarm is the same as the historical alarm.

[0058] S9: If so, determine the current alarm as a repeated alarm, and jump to step S2.

[0059] S10: If not, start the secondary analysis algorithm. If the current alarm is truly valid, mark the current alarm as a new alarm, and at the same time overwrite and save the current alarm to the historical alarm, and jump to step S2. If the current alarm is invalid, directly jump to step S2.

[0060] As Figure 2 shown, a method for solving alarm oscillation based on secondary analysis in this embodiment includes the following steps:

[0061] 1) Use the OTDR module to perform OTDR tests on the optical fiber line, and store the test results and the alarm threshold values as the standard curve in the OTDR module.

[0062] 2) Use the measurement parameters saved in the OTDR module to perform cyclic tests on the monitored line, and obtain test results; the test results include the loss of the event and the optical fiber length.

[0063] 3) Calculate the change in the line loss between the current line loss and the standard curve line loss.

[0064] 4) Determine whether there is an alarm based on the change in line loss and the corresponding alarm threshold. If the alarm exists, the alarm levels are 1, 2, and 3. Level 1 alarm is the most serious, and level 3 alarm is minor. For the convenience of calculation, if the alarm does not exist, record its level as 4.

[0065] 5) If the current alarm level is 4 and the historical alarm is empty, jump to 2) and execute again.

[0066] 6) If the current alarm level is 4 and the historical alarm exists, start the secondary analysis algorithm. If the current alarm is truly valid (the alarm disappears), then mark the current alarm as disappeared, clear the historical alarm, and jump to 2) to run again.

[0067] 7) If the current alarm exists (the alarm level is not 4) and the historical alarm is empty, record the current alarm in the historical alarm and mark it as an alarm generated. Jump to 2) to run again;

[0068] 8) Check whether the current alarm is the same as the historical alarm. The alarm is considered the same if the alarm location and level are both equal, and different if either one is not equal.

[0069] 9) If the current alarm is the same as the historical alarm, the current alarm is a repeated alarm, and jump to 2) to run again.

[0070] 10) If the current alarm is different from the historical alarm, start the secondary analysis algorithm. If the current alarm is truly valid, mark it as a new alarm, and at the same time overwrite and save it to the historical alarm, then jump to 2) to run again; if it is determined that the current alarm is invalid, directly jump to 2) to run.

[0071] As Figure 3 shown, the secondary analysis algorithm distinguishes two cases. One is that the historical alarm location is different from the current alarm location, and it is processed as follows:

[0072] 1) Determine whether the historical alarm level and the current alarm level are adjacent; by adjacent, it means the absolute value of the difference between the alarm levels is 1, and if it is greater than 1, they are not adjacent.

[0073] 2) If the historical alarm level and the current alarm level are not adjacent, determine whether the current alarm is truly valid, end the execution, and return the judgment result.

[0074] 3) Determine the event point of the historical alarm on the current OTDR curve according to the historical alarm location.

[0075] 4) If the event point does not exist, determine whether the current alarm is truly valid, end the execution, and return the judgment result.

[0076] 5) If the event point exists, adjust the alarm threshold downward by th, and re-judge the alarm level corresponding to the change in event loss. If the new alarm level is the same as the historical alarm level, it is determined that the current alarm is a false alarm; otherwise, it is determined that the current alarm is real and valid. End the execution and return the judgment result.

[0077] As Figure 4 shown, the secondary analysis algorithm distinguishes two cases. In the second case, the historical alarm position is the same as the current alarm position but the levels are different. The processing steps are as follows:

[0078] 1) Judge whether the historical alarm level and the current alarm level are adjacent; by adjacent, it means the absolute value of the difference between the alarm levels is 1. If it is greater than 1, they are not adjacent.

[0079] 2) If the historical alarm level and the current alarm level are not adjacent, directly determine that the current alarm is real and valid. End the execution and return the judgment result.

[0080] 3) When the historical alarm and the current alarm levels are adjacent and the severity of the historical alarm is lower than that of the current alarm (equivalent to the deepening of fiber optic line degradation), adjust the alarm threshold of the current alarm upward by th; otherwise, adjust the historical alarm threshold downward by th. 。

[0081] 4) Use the new alarm threshold to re-judge the current alarm level. If the alarm level is the same as the historical alarm level, it is determined that the current alarm is invalid; otherwise, the current alarm is valid.

[0082] As Figure 5 shown, due to the fluctuations in the laser output power and the influence of receiver noise, the loss value of the fiber optic line event will fluctuate within a certain range. The alarm threshold should be dynamically adjusted during use. The adjustment range is as follows:

[0083] 1) Use the OTDR module to perform an OTDR test on the fiber optic line, and store the test result and the alarm threshold as the standard curve in the OTDR module;

[0084] 2) Use the measurement parameters saved in the OTDR module to perform a cyclic test on the monitored line and obtain the test result; the test result includes the loss of the event and the fiber length;

[0085] 3) Calculate the change in the line loss between the current line loss and the standard curve line loss;

[0086] 4) Judge whether the line loss amount exceeds the alarm threshold. If it does not exceed the alarm threshold, record its loss.

[0087] 5) When the line loss amounts recorded in step 4) reach 256 times in total, calculate its maximum value, minimum value, and find their difference.

[0088] 6) Twice this difference is used as the amplitude for upward or downward floating of the alarm threshold, and it is saved in the device.

[0089] It should be noted that, for the sake of the accuracy of the statistical results, the number of statistics should not be less than 256 times. When the number of times does not reach 256 times during the statistical line loss, a line alarm is generated, and 30% of the alarm threshold can be used as the amplitude for upward or downward floating of the alarm.

[0090] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. For the same and similar parts among the embodiments, reference can be made to each other.

[0091] In this article, specific examples are used to elaborate on the principles and implementation manners of the present invention. The descriptions of the above embodiments are only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A method for solving alarm oscillation based on secondary analysis, characterized in that: include: S1: Use an optical time domain reflectometer module to test the monitored line, and store the test results and the alarm threshold value in the optical time domain reflectometer module as a standard curve; the standard curve is used to characterize the initial state of the line to be tested; the standard curve includes test parameters for testing the monitored line and the alarm threshold value of the monitored line; S2: using the test result and the alarm threshold saved by the optical time domain reflectometer module to perform a cyclic test on the monitored line and obtain a test result; the test result includes the loss of the event and the length of the optical fiber; S3: Calculate the change between the current line loss and the line loss of the standard curve; S4: determining whether there is an alarm according to the line loss change and the corresponding alarm threshold, and if so, dividing the alarm level into level 1 alarm, level 2 alarm, level 3 alarm and level 4 alarm according to the severity; the level 4 alarm represents no alarm; S5: If the current alarm level is 4 and the historical alarm is empty, jump to step S2; S6: If the current alarm level is 4 and there are historical alarms, start the secondary analysis algorithm. If the current alarm is real and valid, that is, the alarm disappears, mark the current alarm disappear, clear the historical alarms, and jump to step S2; S7: If the alarm level of the current alarm is not 4 and the historical alarm is empty, the current alarm is recorded in the historical alarm, marked as an alarm, and jumps to step S2; S8: Check whether the current alarm is the same as the historical alarm; S9: If yes, determine the current alarm as a repeated alarm and jump to step S2; S10: If not, start the secondary analysis algorithm. If the current alarm is true and valid, mark the current alarm as a new alarm, and save the current alarm to the historical alarm, and jump to step S2; If the current alarm is invalid, jump directly to step S2.

2. The method for solving alarm oscillation based on secondary analysis according to claim 1, characterized in that: In step S8, the criteria for determining whether the current alarm is the same as the historical alarm are: Alarm positions and levels that are equal at the same time are considered the same.

3. The method for solving alarm oscillation based on secondary analysis according to claim 2, characterized in that: When the location of the historical alarm is different from the current alarm location, the steps of the secondary analysis algorithm include: Determine whether the level of the historical alarm is adjacent to the level of the current alarm; If the level of the historical alarm is not adjacent to the level of the current alarm, the current alarm is judged to be real and valid, the execution is terminated, and the judgment result is returned; Determine the location of the historical alarm at the event point on the current OTDR curve; If the event point does not exist, the current alarm is judged to be true and valid, the execution is terminated, and the judgment result is returned; If the event point exists, the alarm threshold is adjusted downward, and the alarm level corresponding to the loss change of the event is re-determined. If the level of the new alarm is consistent with the historical alarm level, the current alarm is judged to be a false alarm. Otherwise, the current alarm is judged to be real and valid, the execution is terminated, and the judgment result is returned.

4. The method for solving alarm oscillation based on secondary analysis according to claim 2, characterized in that: When the alarm location of the current alarm is the same as the alarm location of the historical alarm, but the alarm levels are different, the process of the secondary analysis algorithm includes: Determine whether the levels of historical alarms and current alarms are adjacent; If the level of the historical alarm is not adjacent to the current alarm level, the current alarm is determined to be true and valid, the execution is terminated, and the judgment result is returned; If the level of the historical alarm is close to the level of the current alarm, and the severity of the historical alarm is lower than that of the current alarm, the alarm threshold is adjusted upward, otherwise the alarm threshold is adjusted downward; The new alarm threshold is used to re-judge the current alarm level. If the alarm level is the same as the level of the historical alarm, the current alarm is judged to be invalid; otherwise, the current alarm is valid.

5. The method for solving alarm oscillation based on secondary analysis according to any one of claims 3 or 4, characterized in that: The criteria for judging whether the levels of historical alarms and current alarms are adjacent are as follows: The absolute value of the difference between the severity of the historical alarm and the current alarm is 1, which means they are adjacent.

6. The method for solving alarm oscillation based on secondary analysis according to any one of claims 3 or 4, characterized in that: The step of adjusting the alarm threshold comprises: It is determined whether the line loss exceeds the alarm threshold. If it does not exceed the alarm threshold, the line loss is recorded. When the recorded line loss reaches a preset number of times, the maximum and minimum values ​​of the recorded line loss are calculated, and the difference between the maximum and minimum values ​​is calculated; Twice the difference is used as the amplitude of the alarm threshold to increase or decrease, and the amplitude is saved in the optical time domain reflectometer module.

7. The method for solving alarm oscillation based on secondary analysis according to claim 6, characterized in that: The preset number of times is not less than 256 times.

8. The method for solving alarm oscillation based on secondary analysis according to claim 7, characterized in that: When the recorded line loss amount does not reach the preset number of times, 30% of the alarm threshold is used as the amplitude of the alarm increase or decrease, and the amplitude is saved in the optical time domain reflectometer module.

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