Subscriber line fault detection device

Abstract

The invention relates to the technical field of line detection, and provides a subscriber line fault detection device, which comprises a pulse generation module, a conversion module and an acquisition module, and is characterized in that the pulse generation module is connected with the conversion module and the acquisition module, and the conversion module is connected with a subscriber line; the pulse generation module is used for generating a first pulse signal for detecting a subscriber line; the conversion module is used for converting the first pulse signal into a first differential signal and converting the second differential signal into a second pulse signal; the acquisition module is used for processing the first pulse signal to obtain a first target signal; according to the invention, the sending module and the acquisition module are integrated, the hardware design is simplified, the conversion module avoids signal loss and reduces the problem of reflection amplitude attenuation, and the accuracy of fault type detection is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of line detection, and in particular to a user line fault detection device. Background Art

[0002] Electronic Time Domain Reflectometry (ETDR) is a test device that feeds the energy pulse or step signal generated by ETDR into the cable to determine the fault along the cable. If there is a break, short circuit, termination, etc. along the cable, the impedance along the cable will suddenly change. The pulse signal fed will generate a reflected signal at the impedance mutation point and return to the sending end. ETDR can determine the location and type of the cable mutation point based on the time delay, polarity and amplitude of the reflected signal.

[0003] At present, ETDR usually uses differential signals to detect cable faults, uses transformers to couple and isolate the sending and receiving signals, and uses differential signal detection modules for signal reception, which makes the circuit design more complicated. In addition to returning the detection signal to the receiving end, the detection signal returned by the line will also be sent back to the sending end at the transformer, causing unnecessary signal loss and reducing the accuracy of fault detection. Summary of the invention

[0004] The present invention provides a user line fault detection device to solve the defects of signal loss caused by complex circuit design in the prior art and reduced accuracy of fault detection, and realizes a simplified user line fault detection device, in which the signal sending module and the acquisition module are integrated, and the conversion module avoids signal loss and reduces the reflection amplitude attenuation problem, thereby improving the accuracy of fault type detection.

[0005] The present invention provides a user line fault detection device, comprising: a pulse generating module, a conversion module and a collection module, wherein: The pulse generation module is connected to the conversion module and the acquisition module respectively, and the conversion module is connected to the user line; A pulse generating module, used for generating a first pulse signal for detecting a user line; A conversion module, used for converting the first pulse signal into a first differential signal, and converting the second differential signal into a second pulse signal; the second differential signal is a signal reflected back from the first differential signal in the process of propagating along the user line; The acquisition module is used to process the first pulse signal to obtain a first target signal; and process the second pulse signal to obtain a second target signal. The first target signal and the second target signal are used to determine the fault location and fault type of the user line.

[0006] According to a user line fault detection device provided by the present invention, the pulse generating module is further used to adjust at least one of the following parameters of the pulse signal: amplitude, length, and width, to obtain a first pulse signal.

[0007] According to a user line fault detection device provided by the present invention, the conversion module includes: a transformer, wherein: the first end of the transformer is respectively connected to the pulse generating module and the acquisition module, the second end of the transformer is grounded, the third end of the transformer and the fourth end of the transformer are respectively connected to the user line, and the fifth end of the transformer is grounded; the transformer is used to convert the first pulse signal into a first differential signal, and convert the second differential signal into a second pulse signal.

[0008] According to a user line fault detection device provided by the present invention, the conversion module also includes: a capacitor C1, a capacitor C2 and a capacitor C3, wherein: the capacitor C1 is connected in series between the first end of the transformer and the pulse generating module, the capacitor C2 is connected in series between the third end of the transformer and the user line, and the capacitor C3 is connected in series between the fourth end of the transformer and the user line; the capacitor C1 is used to remove the DC signal in the first pulse signal; the capacitor C2 is used to remove the DC signal in the positive differential signal in the first differential signal and the DC signal in the positive differential signal in the second differential signal; the capacitor C3 is used to remove the DC signal in the negative differential signal in the first differential signal and the DC signal in the negative differential signal in the second differential signal.

[0009] According to a user line fault detection device provided by the present invention, the conversion module also includes: a common-mode inductor, a first end of the common-mode inductor is connected to the second end of the capacitor C2, the second end of the common-mode inductor is connected to the second end of the capacitor C3, and the third end of the common-mode inductor and the fourth end of the common-mode inductor are both connected to the user line; the common-mode inductor removes the noise interference generated by the line between the transformer and the common-mode inductor to the first differential signal, and removes the noise interference received by the user line and attached to the second differential signal.

[0010] According to a user line fault detection device provided by the present invention, the acquisition module includes: an operational amplifier circuit and an analog-to-digital converter, wherein: the first end of the operational amplifier circuit is respectively connected to the transformer and the capacitor C1, and the second end of the operational amplifier circuit is connected to the analog-to-digital converter; the operational amplifier circuit is used to amplify the first pulse signal to obtain an amplified first pulse signal; amplify the second pulse signal to obtain an amplified second pulse signal; the analog-to-digital converter is used to convert the amplified first pulse signal into a first target signal, and convert the amplified second pulse signal into a second target signal.

[0011] According to a user line fault detection device provided by the present invention, the acquisition module also includes: a resistor, wherein: a first end of the resistor is connected to the connection between the capacitor C1 and the acquisition module, and a second end of the resistor is grounded; the resistor is used to match the impedance of the user line to absorb the second pulse signal reflected back by the user line.

[0012] A user line fault detection device provided according to the present invention further includes a differential cable, and the differential cable is used to connect the conversion module and the user line to transmit the first differential signal and the second differential signal.

[0013] A user line fault detection device provided according to the present invention further includes a processor, the processor is connected to the acquisition module, and the processor is used to determine the location and fault type of the user line based on the first target signal and the second target signal.

[0014] The user line fault detection device provided by the present invention generates a first pulse signal for detecting the user line through a pulse generation module; obtains a first target signal through an acquisition module; converts the first pulse signal into a first differential signal through a conversion module, the first differential signal propagates along the user line, and when the second differential signal is reflected back from the user line, the second differential signal is converted into a second pulse signal; then obtains the second target signal through the acquisition module, and determines the fault of the user line according to the first target signal and the second target signal. In this way, the present invention simplifies the hardware design by integrating the pulse generation module and the acquisition module. When detection is required, the user line detection device is cut into the user line, and the pulse signal reflected back from the user line is directly collected to determine the user line fault. There is no need to perform multi-directional signal coupling at the transformer, thus avoiding signal loss, reducing the reflection amplitude attenuation problem, and improving the accuracy of fault type detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the prior art description are briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0016] Figure 1 It is a structural schematic diagram of a line detection system provided by the prior art.

[0017] Figure 2 This is one of the structural schematic diagrams of the user line fault detection device provided by the present invention.

[0018] Figure 3 This is the second structural schematic diagram of the user line fault detection device provided by the present invention.

[0019] Figure 4 This is the third structural schematic diagram of the user line fault detection device provided by the present invention.

[0020] Figure 5 This is the fourth structural schematic diagram of the user line fault detection device provided by the present invention.

[0021] Figure 6 This is the fifth structural schematic diagram of the user line fault detection device provided by the present invention.

[0022] Figure 7 This is the sixth structural schematic diagram of the user line fault detection device provided by the present invention.

[0023] Figure 8 This is the seventh structural schematic diagram of the user line fault detection device provided by the present invention.

[0024] Fig. 9 This is the eighth structural schematic diagram of the user line fault detection device provided by the present invention.

[0025] Reference numerals: 100: line detection system; 101: signal generating module; 102: signal sending module; 103: coupling transformer; 104: signal receiving module; 105: judgment module; 106: current limiting resistor; 200: user line fault detection device; 210: pulse generating module; 220: conversion module; 230: acquisition module; 240: user line; 221: transformer; 222: common mode inductor; 231: operational amplifier circuit; 232: analog-to-digital converter; 233: resistor; 250: differential cable. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] At present, the method for detecting user lines is that a detection signal sending module and a detection signal receiving module are respectively located at the beginning and the end of the transmission line.

[0028] Figure 1 It is a structural diagram of a line detection system provided by the prior art, such as Figure 1As shown, the line detection system 100 includes: a signal generating module 101, a signal sending module 102, a coupling transformer 103, a signal receiving module 104, a judgment module 105 and a current limiting resistor 106, wherein the user line is located between the signal sending module 102 and the current limiting resistor 106. When performing detection, the signal sending module 102 sends a detection sequence to the differential line, and the end of the differential transmission line is connected to the coupling transformer 103 and the current limiting resistor 106. The detection signal is induced in the secondary coil of the coupling transformer 103, and sent to the signal receiving module 104 for differential-single-end conversion, and then sent to the judgment module 105 for verification and comparison. Among them, the current limiting resistor 106 is only used for current limiting to prevent damage to the coupling transformer 103, and the coupling transformer 103 is used to receive the detection signal received by coupling.

[0029] exist Figure 1 In the line detection system, the sending module and detection module of the user line are arranged on both sides of the transformer, and the line transmission part is not listed. After a line fault occurs, the returned detection signal will return along the line and be sent back to the receiving end at the transformer, but at the same time, it will also be sent back to the sending end, causing unnecessary signal loss. The residual voltage problem on the user line will also affect the signal detection.

[0030] Based on the above problems, the present invention provides a user line detection device, which simplifies the hardware design by integrating the pulse generating module and the acquisition module. When detection is needed, the user line detection device is cut into the user line to directly collect the pulse signal reflected back from the user line to determine the user line fault. There is no need to perform multi-directional signal coupling at the transformer, which avoids signal loss, reduces the problem of reflection amplitude attenuation, and improves the accuracy of fault type detection.

[0031] Combine the following Figure 2-Figure 9 The user line fault detection device of the present invention is described. The user line fault detection device can detect any cable, including but not limited to communication cables, telephone lines, any digital subscriber lines (x Digital Subscriber Line, xDSL), Ethernet broadband lines, etc.

[0032] Figure 2 FIG. 2 is a schematic diagram of the structure of the user line fault detection device 200 provided by the present invention. Figure 2 As shown, the user line fault detection device 200 includes: Pulse generation module 210, conversion module 220 and acquisition module 230, wherein: The pulse generation module 210 is respectively connected to the conversion module 220 and the acquisition module 230, and the conversion module 220 is connected to the user line 240; The pulse generating module 210 is used to generate a first pulse signal for detecting the user line 240; The conversion module 220 is used to convert the first pulse signal into a first differential signal, and convert the second differential signal into a second pulse signal; the second differential signal is a signal reflected back from the first differential signal during the propagation along the user line; The acquisition module 230 is used to process the first pulse signal to obtain a first target signal; process the second pulse signal to obtain a second target signal, and the first target signal and the second target signal are used to determine the fault location and fault type of the user line.

[0033] It should be noted that the pulse generating module 210 is an electronic circuit capable of generating a pulse signal, such as a multivibrator, a circuit composed of a 555 timer, a resistor-capacitor oscillator, and the like.

[0034] It should be noted that the user line can be any suitable line, such as a communication cable, a network cable, a digital user line, etc.

[0035] It should be noted that the conversion between the pulse signal and the differential signal can use any suitable circuit, such as a differential amplifier chip, a transformer 221 coupling circuit, a microcontroller, etc.

[0036] It should be noted that if the user line is broken, spliced, terminated, etc., the impedance of the user line will change suddenly, causing the first differential signal propagating along the user line to generate a second differential signal that is reflected to the transmitting end. During the reflection process, the second differential signal is converted into a corresponding second pulse. In other words, the second differential signal is a signal that is caused by the sudden change in the impedance of the user line, resulting in the reflection of the first differential signal.

[0037] In the embodiment of the present invention, the pulse generation module 210 generates a first pulse signal for detecting the user line; then the conversion module 220 is used to convert the first pulse signal into a first differential signal, the first differential signal propagates along the user line, and when the second differential signal is reflected back from the user line, the second differential signal is converted into a second pulse signal; then the acquisition module 230 is used to obtain the first target signal and the second target signal, and the fault of the user line is determined according to the first target signal and the second target signal. In this way, the present invention integrates the pulse generation module 210 and the acquisition module 230 into one, and when detection is required, the user line detection device is cut into the user line, and the pulse signal reflected back from the user line is directly collected to determine the user line fault, and there is no need to do multi-directional signal coupling at the transformer to avoid signal loss, and the differential detection signal can reduce the reflection amplitude attenuation problem encountered in the electrical time domain reflection and the crosstalk problem on the line, thereby improving the accuracy of fault detection.

[0038] Furthermore, the pulse generating module 210 is also used to adjust at least one of the following parameters of the pulse signal: amplitude, length, and width, to obtain the first pulse signal.

[0039] It should be noted that the pulse generating module 210 can adjust the amplitude, length and width of the pulse signal under the control of the CPU.

[0040] Here, the first pulse signal can be any suitable pulse signal, for example, a high-voltage ultra-short detection pulse signal. The high-voltage ultra-short detection pulse signal is an electrical signal with high voltage and short duration. The pulse edge of the high-voltage ultra-short detection pulse signal can reach 20V / ns (volts / nanoseconds), and the steeper pulse edge can improve the resolution of the fault point of the user line.

[0041] It should be noted that after the pulse generating module 210 sends out a pulse, the circuit is in a high impedance state.

[0042] In the embodiment of the present invention, the pulse generating module 210 is used to adjust the parameters of the pulse signal to obtain a first pulse signal, and the first pulse signal is used to improve the resolution of the fault point, thereby improving the accuracy of user line fault detection.

[0043] Figure 3 FIG. 2 is a second structural diagram of the user line fault detection device 200 provided by the present invention. Figure 3 As shown, the conversion module 220 includes: a transformer 221, wherein: The first end of the transformer 221 is connected to the pulse generating module 210 and the acquisition module 230 respectively, the second end of the transformer is grounded, the third end of the transformer 221 and the fourth end of the transformer 221 are connected to the user line respectively, and the fifth end of the transformer is grounded; The transformer 221 is used to convert the first pulse signal into a first differential signal, and convert the second differential signal into the second pulse signal.

[0044] It should be noted that the principle of the transformer 221 to achieve conversion between the pulse signal and the differential signal is that the first pulse signal is coupled from the primary side of the transformer 221 to the secondary side, and the second differential signal is coupled from the secondary side of the transformer 221 to the primary side.

[0045] It should be noted that the transformer 221 should have five ports. Here, the fifth port of the transformer 221 is the center tap of the secondary coil and should be grounded.

[0046] In the embodiment of the present invention, the conversion between the pulse signal and the differential signal is realized by the transformer 221, and the differential signal is used to reduce the reflection amplitude attenuation problem and the crosstalk problem on the line encountered in the electrical time domain reflection, thereby improving the accuracy of user line fault detection.

[0047] Figure 4 FIG. 3 is a third structural diagram of the user line fault detection device 200 provided by the present invention, as shown in FIG. Figure 4 As shown, the conversion module 220 further includes: capacitor C1, capacitor C2 and capacitor C3, wherein: The capacitor C1 is connected in series between the first end of the transformer 221 and the pulse generating module 210, the capacitor C2 is connected in series between the third end of the transformer 221 and the user line, and the capacitor C3 is connected in series between the fourth end of the transformer 221 and the user line; The capacitor C1 is used to remove the DC signal in the first pulse signal; The capacitor C2 is used to remove the DC signal in the positive differential signal in the first differential signal and the DC signal in the positive differential signal in the second differential signal; The capacitor C3 is used to remove the DC signal in the negative differential signal in the first differential signal and the DC signal in the negative differential signal in the second differential signal.

[0048] Here, the capacitor may be any suitable type of capacitor, such as a fixed capacitor, a fine-tuning capacitor, a plug-in capacitor, a coupling capacitor, etc.

[0049] It should be noted that a capacitor consists of two conductors and an insulating medium. When a DC voltage is applied to both ends of a capacitor, positive charges will accumulate on one plate of the capacitor, while negative charges will accumulate on the other plate. The charges will not move within the conductor to offset this voltage difference, but will stay on the plates, forming static charges. The insulating medium between the two plates of the capacitor (whether solid, liquid or gas) does not allow charges to flow directly from one plate to the other. Therefore, once the capacitor is charged, DC current cannot pass through the capacitor without external energy input.

[0050] It should be noted that the main reasons for using capacitors to isolate current are: when a DC signal is converted into a differential signal, a DC offset may be introduced into the differential signal, and the DC offset will affect the balance of the differential signal, reduce the signal's anti-interference ability, and may cause signal distortion; the DC signal will generate power consumption in the circuit. Therefore, capacitors are required to pre-isolate the DC signal in the signal.

[0051] In the embodiment of the present invention, capacitors are used to isolate DC signals, maintain the balance of differential signals, reduce power consumption, and ensure that differential signals maintain high quality and high reliability during transmission, thereby improving the accuracy of user line fault detection.

[0052] Figure 5 FIG. 4 is a fourth structural diagram of the user line fault detection device 200 provided by the present invention. Figure 5 As shown, the conversion module 220 further includes: a common mode inductor 222, The first end of the common mode inductor 222 is connected to the second end of the capacitor C2, the second end of the common mode inductor 222 is connected to the second end of the capacitor C3, and the third end of the common mode inductor 222 and the fourth end of the common mode inductor 222 are both connected to the user line; The common-mode inductor 222 is used to remove the noise interference generated by the line between the transformer 221 and the common-mode inductor 222 on the first differential signal, and to remove the noise interference added to the second differential signal received by the user line.

[0053] Here, the common-mode inductor 222 is a common-mode interference suppression device with ferrite as the magnetic core, which is composed of two coils of the same size and the same number of turns symmetrically wound on the same ferrite ring magnetic core to form a four-port device.

[0054] Here, noise may include common-mode noise introduced externally by adjacent line pairs, transmission environment, spatial coupling, etc. Common-mode noise refers to interference signals that appear on two signal lines of a circuit at the same time, usually due to external electromagnetic interference or internal circuit failure.

[0055] The principle of common-mode inductor 222 suppressing common-mode noise is that when common-mode noise occurs, current signals of the same magnitude and phase are generated on the two signal lines of the circuit. These current signals induce a magnetic field in the common-mode inductor 222, thereby generating a reverse electromotive force that resists the common-mode noise. This reverse electromotive force will suppress the common-mode noise and convert it into electromagnetic energy.

[0056] In the embodiment of the present invention, the common-mode inductor 222 is used to suppress the common-mode noise introduced from the adjacent line pairs, transmission environment, spatial coupling and other external sources, to avoid the crosstalk problem on the line, to determine the stability and reliability of the circuit, and thus to ensure the accuracy of user line fault detection.

[0057] In the embodiment of the present invention, the newly added AC coupling capacitor and common-mode inductor circuit can suppress the residual voltage signal between the two lines on the line and the common-mode crosstalk noise signal on the line, thereby improving the accuracy of return signal detection and the multi-scenario applicability of line detection.

[0058] Figure 6 FIG. 5 is a structural diagram of a user line fault detection device 200 provided by the present invention. Figure 6 As shown, the acquisition module 230 includes: an operational amplifier circuit 231 and an analog-to-digital converter 232, wherein: The first end of the operational amplifier circuit 231 is connected to the transformer 221 and the capacitor C1 respectively, and the second end of the operational amplifier circuit 231 is connected to the analog-to-digital converter 232; The operational amplifier circuit 231 is used to amplify the first pulse signal to obtain an amplified first pulse signal; and to amplify the second pulse signal to obtain an amplified second pulse signal; The analog-to-digital converter 232 is used to convert the amplified first pulse signal into the first target signal, and convert the amplified second pulse signal into the second target signal.

[0059] It should be noted that the operational amplifier circuit 231 receives the first pulse signal passing through the capacitor C1 and the second pulse signal reflected from the user line respectively; then, the first pulse signal is amplified to obtain the amplified first pulse signal, and the second pulse signal is amplified to obtain the amplified second pulse signal.

[0060] Here, the analog-to-digital converter 232 substantially converts the analog signal into a digital signal. That is, both the first target signal and the second target signal are digital signals.

[0061] In the embodiment of the present invention, the operational amplifier circuit 231 is used to amplify the weak pulse signal to improve the accuracy of user line fault detection, and the analog signal is converted into a digital signal by the analog-to-digital converter 232, thereby improving the efficiency of signal processing, the efficiency of data transmission and the quality of the signal.

[0062] Figure 7 FIG. 6 is a sixth structural diagram of the user line fault detection device 200 provided by the present invention. Figure 7 As shown, the acquisition module 230 also includes a resistor 233, wherein: The first end of the resistor is connected to the connection between the capacitor C1 and the acquisition module 230, and the second end of the resistor is grounded; The resistor is used to match the impedance of the user line to absorb the second pulse signal reflected back from the user line.

[0063] The resistors here can be switched to any resistors with appropriate specifications (resistance value, package, power, etc.), and the principle of line impedance matching can be achieved through the transformer.

[0064] Line impedance refers to the characteristic impedance of the transmission cable of the external user line to be tested.

[0065] It should be noted that by increasing the resistance, the acquisition module 230 is matched with the impedance of the user line, and after absorbing the second differential signal, the second differential signal is suppressed from being reflected again and is no longer sent to the line, ensuring that the signal or energy can be transmitted to the acquisition module 230 to the maximum extent, thereby ensuring the accuracy of user line fault detection.

[0066] Figure 8 FIG. 7 is a structural diagram of a user line fault detection device 200 provided by the present invention. Figure 8 As shown, the user line fault detection device 200 further includes a differential cable 250, and the differential cable 250 is used to connect the conversion module 220 and the user line to transmit the first differential signal and the second differential signal.

[0067] Here, the differential cable 250 is a cable or a differential signal transmission line (PCB) for transmitting differential signals. The differential cable 250 consists of two tightly coupled conductors. The signals on the two conductors are equal in amplitude but opposite in polarity, that is, one line transmits a positive signal and the other line transmits a signal of equal amplitude but opposite in polarity (that is, a negative signal).

[0068] In the embodiment of the present invention, differential signals are transmitted to the user lines by using differential cables 250 or PCB differential lines, thereby maintaining signal stability, reducing signal attenuation during transmission, and preventing crosstalk problems.

[0069] Furthermore, the resistance value of the resistor satisfies the impedance transformation principle of the transformer 221 .

[0070] It should be noted that the length of the differential cable 250 should be as short as possible to reduce the impact on the detection accuracy.

[0071] Here, the coil turns ratio of the transformer 221 refers to the ratio of the coil turns on the primary side (between the first end and the second end) to the coil turns on the secondary side (between the third end and the fourth end).

[0072] It should be noted that, in order to ensure impedance matching, the ratio between the resistance value of the resistor and the impedance value of the user line 240 is equal to the square of the primary-secondary coil turn ratio of the transformer 221. For example, if the impedance of the user line 240 is 100 ohms and the coil turn ratio of the transformer 221 is 1:1, the resistance value of the resistor is 100 ohms.

[0073] Furthermore, the user line fault detection device 200 further includes a processor, which is connected to the acquisition module 230 , and is used to determine the fault of the user line based on the first target signal and the second target signal.

[0074] Here, the processor may be a central processing unit (CPU). The fault of the user line includes: the distance of the fault point and the fault type.

[0075] It should be noted that the processor may include signal processing, fault point distance determination and fault type determination, wherein the distance to the fault point or the fault type may be determined according to the amplitude, width or length of the signal.

[0076] It should be noted that after the acquisition module performs analog-to-digital (AD) sampling on the first target signal and the second target signal, by analyzing the time delay and waveform change of the second target signal relative to the first target signal, it is determined whether the user line has a fault, the fault location and the fault type.

[0077] In the embodiment of the present invention, the fault of the user line is determined by processing and judging the collected first target signal and the second target signal by the processor, thereby improving the accuracy and efficiency of detecting the fault of the user line.

[0078] The following are application scenarios of the user line fault detection device 200 provided by the present invention.

[0079] Fig. 9 FIG. 8 is a structural diagram of a user line fault detection device 200 provided by the present invention. Fig. 9 As shown, the user line fault detection device 200 includes a high-voltage ultra-short pulse generating circuit 210 (i.e., the above-mentioned pulse generating module 210), C1, a resistor 233, an acquisition module 230 (i.e., the above-mentioned operational amplifier circuit 231 and the analog-to-digital converter 232), a transformer 221, C2, C3, a common-mode inductor 222, a differential cable 250 and a user line 240.

[0080] Exemplarily, an implementation method of detecting a user line fault using a user line fault detection device 200 includes: a high-voltage ultra-short pulse generating circuit generates a first pulse signal; the first pulse signal is isolated from a DC signal through C1; then, the first pulse signal after isolating the DC signal is converted into a first differential signal through a transformer 221; the positive differential signal in the first differential signal is transmitted to a common-mode inductor 222 through C2, and the negative differential signal in the first differential signal is transmitted to the common-mode inductor 222 through C3, and the first differential signal is suppressed by the common-mode inductor 222 for noise; then, the first differential signal after noise suppression is transmitted to the user line through a differential cable 250, and when the impedance of the user line suddenly changes due to a fault, the first differential signal is The differential signal will reflect the second differential signal; the second differential signal is transmitted along the differential cable 250 to the common mode inductor 222 to suppress noise, and the positive differential signal in the suppressed second differential signal is transmitted to the transformer 221 through C2, and the negative differential signal in the suppressed second differential signal is transmitted to the transformer 221 through C3; the transformer 221 converts the second differential signal into a second pulse signal, and the signal detection module collects the first pulse signal and the second pulse signal, processes the first pulse signal to obtain the first target signal, and processes the second pulse signal to obtain the second target signal; finally, the first target signal and the second target signal are sent to the processor for signal processing, fault point distance and fault type judgment.

[0081] The user line fault detection device provided by the present invention combines high-voltage ultra-short pulses with differential signals, and integrates the transceiver module. Compared with single-line detection, it has strong anti-interference ability and low loss, and can be used for long-distance cable detection such as telephone lines, xDSL, and network cables. It is simple and efficient. When detection is needed, the user line is cut in for inspection; after the detection is completed, the user line is disconnected.

[0082] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0083] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A user line fault detection device, characterized in that: include: Pulse generation module, conversion module and acquisition module, wherein: The pulse generation module is respectively connected to the conversion module and the acquisition module, and the conversion module is connected to the user line; The pulse generating module is used to generate a first pulse signal for detecting the user line; The conversion module is used to convert the first pulse signal into a first differential signal, and convert the second differential signal into a second pulse signal; the second differential signal is a signal reflected back from the first differential signal during the propagation along the user line; The acquisition module is used to process the first pulse signal to obtain a first target signal; process the second pulse signal to obtain a second target signal, and the first target signal and the second target signal are used to determine the fault location and fault type of the user line.

2. The user line fault detection device according to claim 1, characterized in that: The pulse generating module is further used to adjust at least one of the following parameters of the pulse signal: amplitude, length, and width, to obtain the first pulse signal.

3. The user line fault detection device according to claim 1 or 2, characterized in that: The conversion module Comprising: a transformer, wherein: The first end of the transformer is connected to the pulse generating module and the acquisition module respectively, the second end of the transformer is grounded, the third end of the transformer and the fourth end of the transformer are connected to the user line respectively in an alternating manner, and the fifth end of the transformer is grounded; The transformer is used to convert the first pulse signal into a first differential signal, and convert the second differential signal into the second pulse signal.

4. The user line fault detection device according to claim 3, characterized in that: The conversion module further includes: capacitor C1, capacitor C2 and capacitor C3, wherein: The capacitor C1 is connected in series between the first end of the transformer and the pulse generating module, the capacitor C2 is connected in series between the third end of the transformer and the user line, and the capacitor C3 is connected in series between the fourth end of the transformer and the user line; The capacitor C1 is used to remove the DC signal in the first pulse signal; The capacitor C2 is used to remove the DC signal in the positive differential signal in the first differential signal and the DC signal in the positive differential signal in the second differential signal; The capacitor C3 is used to remove the DC signal in the negative differential signal in the first differential signal and the DC signal in the negative differential signal in the second differential signal.

5. The user line fault detection device according to claim 4, characterized in that: The conversion module further includes: a common mode inductor, The first end of the common mode inductor is connected to the second end of the capacitor C2, the second end of the common mode inductor is connected to the second end of the capacitor C3, and the third end of the common mode inductor and the fourth end of the common mode inductor are both connected to the user line; The common mode inductor is used to remove the noise interference generated by the line between the transformer and the common mode inductor on the first differential signal, and to remove the noise interference added to the second differential signal received by the user line.

6. The user line fault detection device according to claim 4, characterized in that: The acquisition module includes: an operational amplifier circuit and an analog-to-digital converter, wherein: The first end of the operational amplifier circuit is connected to the transformer and the capacitor C1 respectively, and the second end of the operational amplifier circuit is connected to the analog-to-digital converter; The operational amplifier circuit is used to amplify the first pulse signal to obtain an amplified first pulse signal; and amplify the second pulse signal to obtain an amplified second pulse signal; The analog-to-digital converter is used to convert the amplified first pulse signal into the first target signal, and convert the amplified second pulse signal into the second target signal.

7. The user line fault detection device according to claim 5, characterized in that: The acquisition module further includes a resistor, wherein: The first end of the resistor is connected to the connection between the capacitor C1 and the acquisition module, and the second end of the resistor is grounded; The resistor is used to match the impedance of the user line to absorb the second pulse signal reflected back from the user line.

8. The user line fault detection device according to claim 1, characterized in that: A differential cable is also included, and the differential cable is used to connect the conversion module and the user line to transmit the first differential signal and the second differential signal.

9. The user line fault detection device according to claim 7, characterized in that: The resistance value of the resistor satisfies the impedance transformation principle of the transformer.

10. The user line fault detection device according to claim 1, characterized in that: Also includes a processor, The processor is connected to the acquisition module, and is used to determine the location and fault type of the user line based on the first target signal and the second target signal.

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