Detection method for determining coiling length of optical cable

Abstract

The invention relates to the technical field of optical fiber communication testing, in particular to a detection method for determining the coiling length of an optical cable, and solves the problems that the existing optical cable is usually laid under an overhead rod or a well lid, and a certain optical cable length is often coiled under the overhead rod or the well lid, so that the coiling length of the optical cable cannot be directly measured manually; the optical cable vibration detection method comprises the following steps: S1, placing an optical cable vibration detection module beside a machine room or an ODF (Optical Distribution Frame); optical pulse input is performed on the optical fiber and the optical fiber laying area is knocked to cause optical fiber vibration, so that the phase difference of the optical fiber phase changes along with time when the two optical pulses pass through the knocked area before and after, the length of the coiled optical cable can be calculated according to the distance of the phase difference with the same intensity, and the test is simple, convenient and accurate; the problem that the length of the coiled optical cable can be easily tested without digging the ground, opening a well lid and climbing an overhead rod is solved.

Description

Technical Field

[0001] The invention relates to the technical field of optical fiber communication testing, in particular to a detection method for determining the coiled length of an optical cable. Background Art

[0002] OTDR is an optical time domain reflectometer. It is a precise optoelectronic integrated instrument made by using the backscattering produced by Rayleigh scattering and Fresnel reflection when light is transmitted in the optical fiber. It is widely used in the maintenance and construction of optical cable lines and can measure the optical fiber length, attenuation, joint attenuation, etc. The OTDR technology can accurately measure the length of the optical cable.

[0003] However, existing optical cables are usually laid on overhead poles or under manhole covers, and a certain length of optical cable is often coiled under the overhead poles or manhole covers. It is impossible to directly measure the length of the optical cable coiled manually, and the OTDR technology cannot accurately measure the length of the optical cable coiled at a specific location; therefore, it does not meet the existing needs. In this regard, we propose a detection method for determining the coiled length of the optical cable. Summary of the invention

[0004] The object of the present invention is to provide a detection method for determining the coiled length of an optical cable, so as to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a detection method for determining the coiled length of an optical cable, comprising the following steps:

[0006] S1: Place the optical cable vibration detection module in the machine room or next to the ODF rack, connect the optical cable to be tested, select the corresponding optical cable length, perform the test before testing, and obtain the transmission signal strength and time curve of the optical cable to be tested through the original sound mode of the optical cable vibration detection module;

[0007] S2: The tester brings a mobile terminal module and a remote knocking component module, and conducts tests step by step along the optical cable laying route. Before knocking, the threshold signal received by the mobile terminal module is adjusted according to the signal strength sent by the optical cable vibration detection module received by the mobile terminal module. Specifically, the remote knocking component module is used to knock the ground and facilities in the laying direction of the optical cable to be tested step by step, wherein the facilities include the optical cable manhole cover and the optical cable overhead pole. Knocking with the remote knocking component module can cause the optical cable to be tested to vibrate.

[0008] S3: During the knocking detection, the optical cable vibration detection module continuously sends frequency test signals. The optical fiber phase changes with time. Two optical pulses pass through the knocking area one after the other, which will bring about a phase difference, so that the optical cable vibration detection module can detect the corresponding optical cable, sample the phase of the entire optical cable, connect the sampling points to form a curve, and based on the sampling changes of the signal strength displayed at different time points at the same position of the optical cable to be tested, the difference between the signal sampling point and the original state threshold is calculated to effectively identify the signal generated by the knocking of the remote knocking component module. Different knocking frequencies are used to avoid interference caused by external noise and vibration, and a waveform is displayed;

[0009] S4: The sound waves generated by the fixed frequency knocking cause the strain to cause the change of the optical phase. After multiple acquisitions, the mobile terminal module obtains the curve of signal strength and time, which is compared and analyzed with the threshold signal to parse the knocking sound curve. Then, when the knocking sound appears in the same range, the difference between the starting point and the end point of the vibration is calculated and displayed through an algorithm, so that the position and length of the coiled optical fiber can be detected and displayed;

[0010] S5: When the optical cable vibration detection module and the mobile terminal module are connected for data, wireless signal transmission is performed through the 4G / 5G wireless communication module, wherein the 4G / 5G wireless communication module uses the operator's SIM traffic card for communication, so that the mobile terminal module receives and displays the data tested by the optical cable vibration detection module, so that the on-site test personnel can adjust and confirm according to the test data, and use the 4G / 5G wireless communication module to upload the test results to the optical cable vibration detection module, so as to generate the final test report.

[0011] Preferably, the detection method includes an optical cable vibration detection module, a 4G / 5G wireless communication module, a mobile terminal module and a remote knocking component module, and the optical cable vibration detection module and the mobile terminal module are both installed with 4G / 5G wireless communication modules.

[0012] Preferably, the electrical components inside the optical cable vibration detection module are respectively a 1550nm laser, an FPGA, an APD and an ARM, and the 1550nm laser, the FPGA, the APD and the ARM are electrically connected.

[0013] Preferably, the FPGA is used to control the 1550nm laser to generate light pulses inside the optical cable to be tested, and the FPGA receives information from the APD and sends interference peak position data to the ARM.

[0014] Preferably, the APD receives and synchronously collects the phase information of the backward Rayleigh scattered light caused by the knocking vibration, demodulates the phase information of the light through the background software, and displays it using a waveform diagram. The ARM is used to configure and drive each 1550nm laser, FPGA and APD, and complete algorithms such as peak finding and filtering.

[0015] Preferably, the 4G / 5G wireless communication module can transmit the waveform detected by the optical cable vibration detection module to the mobile terminal module in real time.

[0016] Preferably, the mobile terminal module is an iPad or a mobile phone provided with a communication port, and the iPad or the mobile phone has a built-in APP software.

[0017] Preferably, the remote striking component is a metal hammer, a pressure sensor is provided inside the metal hammer, and the pressure sensor is electrically connected to the mobile terminal module.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention inputs light pulses into the optical fiber and knocks on the optical fiber laying area to cause the optical fiber to vibrate, so that when two light pulses pass through the knocking area front and back, a phase difference will occur in the optical fiber phase as time changes. According to the distance of the phase difference with the same intensity, the length of the reeled optical cable can be calculated. The test is simple and accurate, and solves the problem of easily testing the length of the reeled optical cable without digging the ground, opening the manhole cover, or climbing the overhead pole. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 A schematic diagram of a test scenario of the present invention;

[0022] Figure 3 It is a schematic diagram of the overall structure of the present invention;

[0023] Figure 4 It is a schematic diagram of the overall process of the present invention;

[0024] Figure 5 Schematic diagram of the waveform of the knocking signal of the present invention;

[0025] Figure 6 A schematic diagram of phase information of backward Rayleigh scattered light of the present invention;

[0026] Figure 7 It is a schematic diagram of the phase-sensitive OTDR acoustic wave positioning of the present invention;

[0027] Figure 8 It is a structural schematic diagram of the optical cable vibration detection module of the present invention. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0029] See also Figures 1 to 8 The present invention provides an embodiment: a detection method for determining the coiled length of an optical cable, comprising the following steps:

[0030] S1: Place the optical cable vibration detection module in the machine room or next to the ODF rack, connect the optical cable to be tested, select the corresponding optical cable length, perform the test before testing, and obtain the transmission signal strength and time curve of the optical cable to be tested through the original sound mode of the optical cable vibration detection module;

[0031] S2: The tester brings a mobile terminal module and a remote knocking component module, and conducts tests step by step along the optical cable laying route. Before knocking, the threshold signal received by the mobile terminal module is adjusted according to the signal strength sent by the optical cable vibration detection module received by the mobile terminal module. Specifically, the remote knocking component module is used to knock the ground and facilities in the laying direction of the optical cable to be tested step by step, wherein the facilities include the optical cable manhole cover and the optical cable overhead pole. Knocking with the remote knocking component module can cause the optical cable to be tested to vibrate.

[0032] S3: During the knocking detection, the optical cable vibration detection module continuously sends frequency test signals. The optical fiber phase changes with time. Two optical pulses pass through the knocking area one after the other, which will bring about a phase difference, so that the optical cable vibration detection module can detect the corresponding optical cable, sample the phase of the entire optical cable, connect the sampling points to form a curve, and based on the sampling changes of the signal strength displayed at different time points at the same position of the optical cable to be tested, the difference between the signal sampling point and the original state threshold is calculated to effectively identify the signal generated by the knocking of the remote knocking component module. Different knocking frequencies are used to avoid interference caused by external noise and vibration, and a waveform is displayed;

[0033] S4: The sound waves generated by the fixed frequency knocking cause the strain to cause the change of the optical phase. After multiple acquisitions, the mobile terminal module obtains the curve of signal strength and time, which is compared and analyzed with the threshold signal to parse the knocking sound curve. Then, when the knocking sound appears in the same range, the difference between the starting point and the end point of the vibration is calculated and displayed through an algorithm, so that the position and length of the coiled optical fiber can be detected and displayed;

[0034] S5: When the optical cable vibration detection module and the mobile terminal module are connected for data, wireless signal transmission is performed through the 4G / 5G wireless communication module, wherein the 4G / 5G wireless communication module uses the operator's SIM traffic card for communication, so that the mobile terminal module receives and displays the data tested by the optical cable vibration detection module, so that the on-site test personnel can adjust and confirm according to the test data, and use the 4G / 5G wireless communication module to upload the test results to the optical cable vibration detection module, so as to generate the final test report.

[0035] See also Figures 1 to 3 The detection method includes an optical cable vibration detection module, a 4G / 5G wireless communication module, a mobile terminal module and a remote knocking component module. The 4G / 5G wireless communication module is installed inside the optical cable vibration detection module and the mobile terminal module. The 4G / 5G wireless communication module can transmit the waveform detected by the optical cable vibration detection module to the mobile terminal module in real time, which is convenient for testers to view and mark the on-site test results.

[0036] See also Figure 8 The electrical components inside the optical cable vibration detection module are 1550nm laser, FPGA, APD and ARM. The 1550nm laser, FPGA, APD and ARM are electrically connected. FPGA is used to control the 1550nm laser to generate light pulses inside the optical cable to be tested. FPGA receives the information of APD and sends the interference peak position data to ARM. APD receives and synchronously collects the phase information of the backward Rayleigh scattered light caused by the knocking vibration, demodulates the phase information of the light through the background software, and uses a waveform diagram to display it. ARM is used to configure and drive each 1550nm laser, FPGA and APD, and complete peak search and filtering algorithms. The optical cable vibration detection module is used to send a test pulse width signal and receive a knocking component. The knocking vibration signal will affect the phase of the transmitted light in the optical fiber. The phase information of the light is demodulated through the background software and displayed using a waveform diagram.

[0037] See also Figure 2 and Figure 3 The mobile terminal module is an iPad or mobile phone with a communication port. The iPad or mobile phone has a built-in APP software for receiving and displaying the data tested by the optical cable vibration detection module. The on-site tester adjusts and confirms the test data and uploads the test results to the optical cable vibration detection module to generate the final test report.

[0038] The remote knocking component is a metal hammer with a pressure sensor inside. The pressure sensor is electrically connected to the mobile terminal module. The metal hammer is used to knock on the ground, manhole cover, overhead pole and cause the optical cable to vibrate, thereby causing the optical phase to change, so that the optical cable vibration detection module can detect the corresponding optical cable and display a waveform diagram. Different knocking frequencies are used to avoid interference caused by external noise and vibration.

[0039] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A detection method for determining the coiled length of an optical cable, characterized in that: The steps include: S1: Place the optical cable vibration detection module in the machine room or next to the ODF rack, connect the optical cable to be tested, select the corresponding optical cable length, perform the test before testing, and obtain the transmission signal strength and time curve of the optical cable to be tested through the original sound mode of the optical cable vibration detection module; S2: The tester brings a mobile terminal module and a remote knocking component module, and conducts tests step by step along the optical cable laying route. Before knocking, the threshold signal received by the mobile terminal module is adjusted according to the signal strength sent by the optical cable vibration detection module received by the mobile terminal module. Specifically, the remote knocking component module is used to knock the ground and facilities in the laying direction of the optical cable to be tested step by step, wherein the facilities include the optical cable manhole cover and the optical cable overhead pole. Knocking with the remote knocking component module can cause the optical cable to be tested to vibrate. S3: During the knocking detection, the optical cable vibration detection module continuously sends frequency test signals. The optical fiber phase changes with time. Two optical pulses pass through the knocking area one after the other, which will bring about a phase difference, so that the optical cable vibration detection module can detect the corresponding optical cable, sample the phase of the entire optical cable, connect the sampling points to form a curve, and based on the sampling changes of the signal strength displayed at different time points at the same position of the optical cable to be tested, the difference between the signal sampling point and the original state threshold is calculated to effectively identify the signal generated by the knocking of the remote knocking component module. Different knocking frequencies are used to avoid interference caused by external noise and vibration, and a waveform is displayed; S4: The sound waves generated by the fixed frequency knocking cause the strain to cause the change of the optical phase. After multiple acquisitions, the mobile terminal module obtains the curve of signal strength and time, which is compared and analyzed with the threshold signal to parse the knocking sound curve. Then, when the knocking sound appears in the same range, the difference between the starting point and the end point of the vibration is calculated and displayed through an algorithm, so that the position and length of the coiled optical fiber can be detected and displayed; S5: When the optical cable vibration detection module and the mobile terminal module are connected for data, wireless signal transmission is performed through the 4G / 5G wireless communication module, wherein the 4G / 5G wireless communication module uses the operator's SIM traffic card for communication, so that the mobile terminal module receives and displays the data tested by the optical cable vibration detection module, so that the on-site test personnel can adjust and confirm according to the test data, and use the 4G / 5G wireless communication module to upload the test results to the optical cable vibration detection module, so as to generate the final test report.

2. A detection method for determining the coiled length of an optical cable according to claim 1, characterized in that: The detection method includes an optical cable vibration detection module, a 4G / 5G wireless communication module, a mobile terminal module and a remote knocking component module, and the optical cable vibration detection module and the mobile terminal module are both installed with 4G / 5G wireless communication modules.

3. A detection method for determining the coiled length of an optical cable according to claim 2, characterized in that: The electrical components inside the optical cable vibration detection module are respectively a 1550nm laser, an FPGA, an APD and an ARM, and the 1550nm laser, the FPGA, the APD and the ARM are electrically connected.

4. A detection method for determining the coiled length of an optical cable according to claim 3, characterized in that: The FPGA is used to control the 1550nm laser to generate light pulses inside the optical cable to be tested. The FPGA receives the information of the APD and sends the interference peak position data to the ARM.

5. A detection method for determining the coiled length of an optical cable according to claim 4, characterized in that: The APD receives and synchronously collects the phase information of the backward Rayleigh scattered light caused by the knocking vibration, demodulates the phase information of the light through the background software, and displays it using a waveform diagram. The ARM is used to configure and drive each 1550nm laser, FPGA and APD, and complete algorithms such as peak finding and filtering.

6. A detection method for determining the coiled length of an optical cable according to claim 5, characterized in that: The 4G / 5G wireless communication module can transmit the waveform detected by the optical cable vibration detection module to the mobile terminal module in real time.

7. A detection method for determining the coiled length of an optical cable according to claim 6, characterized in that: The mobile terminal module is an iPad or a mobile phone provided with a communication port, and the iPad or the mobile phone is equipped with a built-in APP software.

8. A detection method for determining the coiled length of an optical cable according to claim 7, characterized in that: The remote striking component is a metal hammer, a pressure sensor is arranged inside the metal hammer, and the pressure sensor is electrically connected to the mobile terminal module.

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