Connection test device, method and system for optical fiber and optical modem

Abstract

The invention discloses a connection test device, method and system for an optical fiber and an optical modem, and the device comprises an optical fiber bending module, a first photoelectric detection module, a signal amplifier, an ADC module, a time sequence control circuit, an FPGA control logic module, a return loss measurement access port, a laser, and a second photoelectric detection module. The FPGA control logic module comprises a burst light detection unit and a return loss measurement unit. According to the invention, network disconnection of a user cannot be caused, whether the port of the optical splitter is connected with the optical modem can be accurately judged, and data support is provided for cleaning of the virtually occupied port.

Description

Technical Field

[0001] The invention relates to optical fiber communication testing technology, and in particular to a connection testing device, method and system for optical fiber and optical modem. Background Art

[0002] As the main transmission medium for modern Internet communications, optical fiber has the advantages of high data transmission rate and low signal attenuation. More and more users are beginning to use optical fiber networks for communication. Usually, each building will be equipped with a fiber splitter box, which is equipped with a splitter. The input port of the splitter is connected to the optical line terminal (OLT), and there are multiple output ports. The output ports are connected to the optical modem of each household through the household optical fiber. The optical modem is also called a single-port optical terminal or optical modem, which can modulate optical signals into electrical signals so that computers and other devices can understand and process these signals. Therefore, detecting the connection status between the household optical fiber and the optical modem is the basis for ensuring the quality of communication.

[0003] In real life, when fiber optic network users move broadband or change network operators, the original system network uses soft disassembly (network shutdown), and installation and maintenance personnel do not need to go to the site a second time to remove the originally connected home fiber. In addition, there are many ports in the on-site fiber splitter box. If the wrong port of other users who are using the fiber optic network is unplugged, it will cause users to complain about network disconnection. If a new user is added, a new splitter will be added, and the new user's optical modem will be connected to the new splitter's wired transmission port. The port previously connected to the splitter will still maintain the home fiber connection, but the home fiber is not connected to the optical modem, resulting in a virtual port occupancy. Over time, the virtual occupancy rate of the splitter will become higher and higher, resulting in a large waste of resources, and the addition of splitters will also increase costs.

[0004] In order to detect whether the incoming optical fiber led out from the port of the splitter is connected to the optical modem, the existing technology usually uses a PON network tester to pull out the fiber test, that is, pull out the incoming optical fiber from the port of the splitter, and then test whether the current optical fiber is in a connected state. This process requires detection in the fiber pulling state (interrupting the network). If the wrong fiber is pulled out, it will still cause the user to be disconnected from the network. Moreover, the PON network tester uses the conventional winding-free return loss measurement (OTDR) method to pull out the fiber to test whether the optical modem is connected. The calculation of this method requires not only the peak power but also the starting power. In the application scenario of optical modem testing, due to the complexity of the actual optical path and the particularly high blind area requirements, the starting power cannot be accurately obtained in most cases, resulting in the inability of the traditional OTDR method to accurately measure the emissivity value, and thus cannot accurately determine whether the port of the splitter is connected to the optical modem. Summary of the invention

[0005] In view of the problems existing in the prior art, the purpose of the present invention is to provide a connection test device, method and system that will not cause users to disconnect from the network and can accurately determine whether the port of the splitter is connected to the optical modem. It can quickly determine and clean up the virtual occupied pigtails, release the virtual occupied port resources, greatly save investment, and have high economic value.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] A connection test device for an optical fiber and an optical modem, comprising an optical fiber bending module, a first photoelectric detection module, a signal amplifier, an ADC module, a timing control circuit, an FPGA control logic module, a return loss measurement access port, a laser, and a second photoelectric detection module, wherein:

[0008] The optical fiber bending module is used to bend the household optical fiber into a preset radius, so that the optical signal transmitted in the household optical fiber leaks to the outer layer of the household optical fiber;

[0009] The first photoelectric detection module is arranged near the optical fiber bending module and is close to the outer layer of the access optical fiber, and is used to detect the burst optical signal leaked from the outer layer of the access optical fiber and perform photoelectric conversion;

[0010] The signal amplifier and ADC module are used to amplify the received electrical signal and perform digital conversion;

[0011] The timing control circuit is used to perform envelope detection on the digital electrical signal of the burst optical signal to obtain a complete pulse of the burst optical signal;

[0012] The burst optical detection unit is used to calculate the pulse interval between the complete pulses of the burst optical signal detected by the timing control circuit within a preset time period, and calculate the average value of all complete pulses according to the pulse interval. If the average value is greater than the preset ratio of the noise signal, it is determined that there is a burst optical signal in the home optical fiber, otherwise it is determined that there is no burst optical signal in the home optical fiber;

[0013] The return loss measurement access port is used to access the home optical fiber;

[0014] The laser is used to emit laser light to the connected household optical fiber;

[0015] The second photoelectric detection module is used to receive the echo signal reflected back by the emitted laser and convert it into an electrical signal;

[0016] The return loss measurement unit is used to receive the digital electrical signal of the echo signal obtained after being processed by the signal amplifier and the ADC module, calculate the reflectivity value of the echo signal according to the following formula, and judge whether the home optical fiber is connected to the optical modem according to the reflectivity value:

[0017] RL=RL ref -(P onu -P ref )

[0018] Where RL is the reflectivity value of the echo signal, RL ref is the preset reference reflectivity, P onu is the peak reflected power of the echo signal, P ref is the preset reference reflected power peak value.

[0019] Furthermore, the first photoelectric detection module includes two photoelectric detectors, and a filter film is coated on the window of each photoelectric detector. The filter film only passes the burst optical signals with wavelengths of 1270nm and 1310nm, and isolates the optical signals of other wavelengths.

[0020] Furthermore, the device also includes a display screen, an MCU and a button module. The display screen, the button module and the FPGA control logic module are respectively connected to the MCU. The MCU is used to receive a trigger signal sent by the button module, generate corresponding instructions and send them to the corresponding module, and display the judgment results and other test results of the FPGA control logic module on the display screen.

[0021] Furthermore, the return loss measurement unit specifically includes:

[0022] A receiving subunit, used for receiving the digital electrical signal of the echo signal obtained after being processed by the signal amplifier and the ADC module;

[0023] The reflected power peak value calculation subunit is used to calculate the reflected power peak value P of the echo signal according to the echo signal digital electrical signal. onu ;

[0024] The reflectivity calculation subunit is used to calculate the reflectivity value of the echo signal according to the following formula:

[0025] RL=RL ref -(P onu -P ref )

[0026] The judgment subunit is used to judge whether the access optical fiber is connected to the optical modem according to the reflectivity value according to the following rules:

[0027] When RL≥the first preset threshold, the access optical fiber is not connected to the optical modem;

[0028] When the second preset threshold ≤ RL ≤ the first preset threshold, the access optical fiber is connected to the optical modem;

[0029] When RL≤the second preset threshold, the fiber entering the home is broken.

[0030] A method for testing the connection between an optical fiber and an optical modem is implemented based on the above-mentioned testing device, and the method specifically comprises the following steps:

[0031] S1. Establishing a communication connection between the analysis terminal and the test device according to claim 1;

[0032] S2. When the incoming optical fiber is connected to the optical splitter port, the incoming optical fiber is placed in the optical fiber bending module to perform burst light detection on the incoming optical fiber. When the burst light detection unit obtains the burst light detection result, the burst light detection result is sent to the analysis terminal.

[0033] S3, when the burst light detection result shows that there is a burst light signal in the incoming optical fiber, the analysis terminal determines that the incoming optical fiber is connected to the optical modem, records the splitter port connected to the incoming optical fiber as in use, and uploads it to the resource management center, otherwise, executes step S4;

[0034] S4, unplug the household optical fiber from the optical splitter, and insert it into the return loss measurement access port to perform return loss measurement. When the return loss measurement unit obtains a judgment result of whether the household optical fiber is connected to the optical modem according to the reflectivity value, the connection judgment result is sent to the analysis terminal;

[0035] S5, the analysis terminal determines that the incoming optical fiber with a connection judgment result of not being connected to the optical modem is a virtually occupied port optical fiber, updates the optical splitter port connected to the virtually occupied port optical fiber to a virtually occupied state, and uploads it to a resource center; determines that the incoming optical fiber with a connection judgment result of being connected to the optical modem is in an access state, updates the optical splitter port connected to the incoming optical fiber to an in-use state, and uploads it to a resource center;

[0036] S6. The resource center stores the status of all splitter ports.

[0037] A connection test system between an optical fiber and an optical modem, comprising the above-mentioned test device, an analysis terminal and a resource center, wherein:

[0038] The test device is used for performing burst light detection of the incoming optical fiber when the incoming optical fiber is connected to the optical splitter port and when the incoming optical fiber is placed in the optical fiber bending module, and sending the burst light detection result to the analysis terminal when the burst light detection unit obtains the burst light detection result; and performing return loss measurement when the incoming optical fiber is unplugged from the optical splitter and inserted into the return loss measurement access port, and sending the connection judgment result to the analysis terminal when the return loss measurement unit obtains the judgment result of whether the incoming optical fiber is connected to the optical modem according to the reflectivity value;

[0039] The analysis terminal is used for, when receiving the burst light detection result, when the burst light detection result is that there is a burst light signal in the household optical fiber, determining that the household optical fiber is connected to the optical modem, recording the optical splitter port connected to the household optical fiber as being in use, and uploading it to the resource management center; and when receiving the connection judgment result, determining the household optical fiber whose connection judgment result is that the optical modem is not connected as a virtually occupied port optical fiber, updating the optical splitter port connected to the virtually occupied port optical fiber to the virtually occupied state, and uploading it to the resource center, determining the household optical fiber whose connection judgment result is that the optical modem is connected as being in access state, updating the optical splitter port connected to the household optical fiber to the in-use state, and uploading it to the resource center;

[0040] The resource center is used to store the status of all splitter ports.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] 1. The present invention first uses burst light detection to preliminarily determine whether the household optical fiber is in use. If it is not in use, the fiber is unplugged for echo detection, which will not cause the user who is using the network to be disconnected;

[0043] 2. The present invention implements envelope detection and burst light detection unit through a timing control circuit, thereby realizing burst light detection of weak signals and improving detection accuracy;

[0044] 3. The return loss measurement unit of the present invention adopts a reference calibration method to calculate the reflectivity value, and there is no need to accurately obtain the starting power, which further improves the accuracy of detection;

[0045] 4. The photoelectric detector of the present invention uses coating technology to achieve burst light filtering, which reduces the difficulty of subsequent signal processing, reduces burst light signal detection errors, and further improves the accuracy of burst light detection.

[0046] 5. The optical fiber and optical modem connection test device, method and system of the present invention can quickly determine and clean up the virtual occupied pigtails, release the virtual occupied port resources, greatly save investment, and have high economic benefit value. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a structural schematic diagram of a connection test device between an optical fiber and an optical modem provided by the present invention;

[0048] Figure 2 It is a schematic structural diagram of the optical fiber bending module and the first photoelectric detection module provided by the present invention;

[0049] Figure 3 is a diagram of the filtering characteristics of the filter film of the photodetector provided by the present invention;

[0050] Figure 4 is a schematic diagram of a burst optical signal provided by the present invention;

[0051] Figure 5 It is a schematic diagram of a return loss measurement access port provided by the present invention;

[0052] Figure 6 It is a schematic diagram of reflectivity calculation provided by the present invention;

[0053] Figure 7 The present invention is a flowchart of a method for testing the connection between an optical fiber and an optical modem. DETAILED DESCRIPTION

[0054] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0055] Embodiment 1

[0056] The embodiment of the present invention provides a connection test device between an optical fiber and an optical modem. Figure 1 As shown, it includes an optical fiber bending module, a first photoelectric detection module, a signal amplifier, an ADC module, a timing control circuit, an FPGA control logic module, a return loss measurement access port, a laser, and a second photoelectric detection module, wherein:

[0057] The optical fiber bending module is used to bend the household optical fiber into a preset radius, so that the optical signal transmitted in the household optical fiber leaks to the outer layer of the household optical fiber;

[0058] The first photoelectric detection module is arranged near the optical fiber bending module and is close to the outer layer of the access optical fiber, and is used to detect the burst optical signal leaked from the outer layer of the access optical fiber and perform photoelectric conversion;

[0059] The signal amplifier and ADC module are used to amplify the received electrical signal and perform digital conversion;

[0060] The timing control circuit is used to perform envelope detection on the digital electrical signal of the burst optical signal to obtain a complete pulse of the burst optical signal;

[0061] The burst optical detection unit is used to calculate the pulse interval between the complete pulses of the burst optical signal detected by the timing control circuit within a preset time period, and calculate the average value of all complete pulses according to the pulse interval. If the average value is greater than the preset ratio of the noise signal, it is determined that there is a burst optical signal in the home optical fiber, otherwise it is determined that there is no burst optical signal in the home optical fiber;

[0062] The return loss measurement access port is used to access the home optical fiber;

[0063] The laser is used to emit laser light to the connected household optical fiber;

[0064] The second photoelectric detection module is used to receive the echo signal reflected back by the emitted laser and convert it into an electrical signal;

[0065] The return loss measurement unit is used to receive the digital electrical signal of the echo signal obtained after being processed by the signal amplifier and the ADC module, calculate the reflectivity value of the echo signal according to the following formula, and judge whether the home optical fiber is connected to the optical modem according to the reflectivity value:

[0066] RL=RL ref -(P onu -P ref )

[0067] Where RL is the reflectivity value of the echo signal, RL ref is the preset reference reflectivity, P onu is the peak reflected power of the echo signal, P ref is the preset reference reflected power peak value.

[0068] In order to improve the usability of the test device, the test device may also include a display screen, an MCU and a button module. The display screen, the button module and the FPGA control logic module are respectively connected to the MCU. The button module may include an on and off button for the device, an on and off button for burst light detection, and an on and off button light for return loss measurement. The MCU is used to receive a trigger signal sent by the button module, generate a corresponding instruction and send it to a corresponding module, and display the judgment result of the FPGA control logic module and other test results on the display screen, such as the result of whether there is a burst light signal in the household optical fiber, the specific value of the burst light signal, the reflectivity value of the echo signal, and the judgment result light of whether the household optical fiber is connected to the optical modem.

[0069] like Figure 2 As shown, the optical fiber bending module includes an upper clamping member 1 and a lower clamping member 2. A protrusion with a radius of the preset radius is provided below the upper clamping member 1, and a depression with a radius of the preset radius is provided above the lower clamping member 2. The upper clamping member 1 and the lower clamping member 2 are tightly matched. When the home-entry optical fiber 3 is clamped between the upper clamping member 1 and the lower clamping member 2, the home-entry optical fiber can be bent to a preset radius, the total reflection feature of the home-entry optical fiber is destroyed, and part of the burst optical signal transmitted internally will leak to the outer layer of the optical fiber and be received by the first photoelectric detection module composed of photodetectors P1 and P2.

[0070] It should be noted that, in other embodiments, the optical fiber bending module can also be set to other shapes or other structures. For example, the optical fiber bending module can be set to a groove with a radius of the preset radius, and the incoming optical fiber can be placed in the groove to bend the incoming optical fiber to the preset radius.

[0071] Since the optical signal to be detected by the present invention comes from the optical modem, but in the PON network, the optical fiber has both upstream and downstream optical signals. In the EPON / GPON network, the wavelength of the upstream optical signal is 1310nm, and the wavelength of the downstream optical signal is 1490nm. In the XGPON network, the wavelength of the upstream optical signal is 1270nm, and the wavelength of the downstream optical signal is 1577nm. The material of the ordinary photodetector is InGaAs, and the wavelength response range is about 700-1700nm. Obviously, if all the upstream and downstream signals are detected, it will affect the judgment. Therefore, in this embodiment, the windows of the photodetectors P1 and P2 are coated with filter films, and only the upstream optical signals with wavelengths of 1270nm and 1310nm are allowed to pass, and the optical signals of other wavelengths are isolated, thereby solving this problem. Since the upstream optical signal sent by the optical modem in the PON network is time-division multiplexed, that is, each optical modem only occupies one time slot of the OLT, the upstream optical signal is an intermittent burst optical signal. Figure 3 This is a diagram of the filtering characteristics of the filter film plated on the windows of the photodetectors P1 and P2.

[0072] According to the XGPON protocol specification, the shortest frame length of the burst optical signal is 10ns. Therefore, the duration of the leaked burst optical signal is very short, only 10 to 200ns. During this period, the burst optical signal is not all high level, but a combination of high and low levels, such as Figure 4 As shown. Moreover, the leakage light intensity is very weak, about -50dBm. In addition, the interval of the leaked burst optical signal in different environments is different, some may be 125us, and some may be 1ms, which makes the burst optical signal very difficult to identify and detect, and the misjudgment rate is high. In order to solve this problem, the present invention synchronizes the uplink time slot interval of the timing controller to 125us, and then performs envelope detection to obtain a complete pulse of the burst optical signal within a polling cycle, such as Figure 4 As shown in the red part, the burst optical detection unit then calculates the pulse interval between the complete pulses of the burst optical signal detected by the timing control circuit within a preset time period (e.g., 100ms), and calculates the average value of all complete pulses based on the pulse interval. If the average value is greater than a preset ratio of the noise signal (e.g., 20%), it is determined that there is a burst optical signal in the access optical fiber, otherwise it is determined that there is no burst optical signal in the access optical fiber.

[0073] If there is a burst optical signal in the incoming fiber, it means that the incoming fiber is being used and connected to an optical modem. If there is no burst optical signal, it means that the incoming fiber is not in use, but it is not clear whether it is not connected to an optical modem or it is connected but not powered on. In this case, return loss measurement can be used to determine. Specifically, because the incoming fiber is not in use at this time, the incoming fiber can be unplugged from the port and then connected to the return loss measurement access port T1, such as Figure 5 As shown, the laser is controlled to emit laser to the connected household optical fiber, and the reflectivity value of the echo signal is measured.

[0074] The calculation and judgment of the reflectivity value of the echo signal is realized by the echo detection unit, which specifically includes:

[0075] A receiving subunit, used for receiving the digital electrical signal of the echo signal obtained after being processed by the signal amplifier and the ADC module;

[0076] The reflected power peak value calculation subunit is used to calculate the reflected power peak value P of the echo signal according to the echo signal digital electrical signal. onu ;

[0077] The reflectivity calculation subunit is used to calculate the reflectivity value of the echo signal according to the following formula:

[0078] RL=RL ref -(P onu -P ref )

[0079] Where RL is the reflectivity value of the echo signal, RL ref is the preset reference reflectivity, P onu is the peak reflected power of the echo signal, P ref is the preset reference reflected power peak, RL ref is the preset reference reflectivity and P ref The preset reference reflected power peak value can be obtained through testing, such as Figure 6 As shown;

[0080] The judgment subunit is used to judge whether the access optical fiber is connected to the optical modem according to the reflectivity value according to the following rules:

[0081] When RL ≥ the first preset threshold (-20 dBm), the access optical fiber is not connected to the optical modem;

[0082] When the second preset threshold value (-40 dBm) ≤ RL ≤ the first preset threshold value (-20 dBm), the optical fiber to the home is connected to the optical modem;

[0083] When RL≤the second preset threshold (-40dBm), the access optical fiber is broken.

[0084] The present invention adopts a reference calibration method to calculate the reflectivity value, and the method can accurately calculate the reflectivity value without requiring a starting point power.

[0085] Embodiment 2

[0086] This embodiment provides a method for testing the connection between an optical fiber and an optical modem. The method is implemented based on the test device of the first embodiment. Figure 7 As shown, the method specifically comprises the following steps:

[0087] S1. Establishing a communication connection between the analysis terminal and the test device according to claim 1, such as a Bluetooth connection or a wired connection;

[0088] S2. When the incoming optical fiber is connected to the optical splitter port, the incoming optical fiber is placed in the optical fiber bending module to perform burst light detection on the incoming optical fiber. When the burst light detection unit obtains the burst light detection result, the burst light detection result is sent to the analysis terminal.

[0089] S3, when the burst light detection result shows that there is a burst light signal in the incoming optical fiber, the analysis terminal determines that the incoming optical fiber is connected to the optical modem, records the splitter port connected to the incoming optical fiber as in use, and uploads it to the resource management center, otherwise, executes step S4;

[0090] S4, unplug the household optical fiber from the optical splitter, and insert it into the return loss measurement access port to perform return loss measurement. When the return loss measurement unit obtains a judgment result of whether the household optical fiber is connected to the optical modem according to the reflectivity value, the connection judgment result is sent to the analysis terminal;

[0091] S5, the analysis terminal determines that the incoming optical fiber with a connection judgment result of not being connected to the optical modem is a virtually occupied port optical fiber, updates the optical splitter port connected to the virtually occupied port optical fiber to a virtually occupied state, and uploads it to a resource center; determines that the incoming optical fiber with a connection judgment result of being connected to the optical modem is in an access state, updates the optical splitter port connected to the incoming optical fiber to an in-use state, and uploads it to a resource center;

[0092] S6. The resource center stores the status of all splitter ports.

[0093] The analysis terminal may be specifically an APP application on a smart mobile terminal such as a mobile phone or a tablet computer. In addition to status judgment and data forwarding, the analysis terminal may also realize functions such as analysis and statistics to facilitate viewing of the status of the splitter port, and may also receive data or instructions issued by the resource center, for example, viewing all the splitter ports in the virtual occupied state, cleaning up the household optical fiber connected to the splitter ports in the virtual occupied state, updating the splitter ports to the available state, and then reporting to the resource center, etc. In addition to storing the status of all splitter ports, the resource center may also perform statistics and analysis on the status of all splitter ports, and send the status of the splitter ports to the analysis terminal, instructing to clean up the splitter ports in the virtual occupied state, etc.

[0094] It should be noted that, if conditions permit, the analysis terminal can also be integrated with the test device into one device, that is, corresponding hardware modules and software programs are added to the test device to achieve the functions that the analysis terminal can achieve.

[0095] Embodiment 3

[0096] An embodiment of the present invention provides a connection test system between an optical fiber and an optical modem, comprising the test device, analysis terminal and resource center described in Embodiment 1, wherein:

[0097] The test device is used for performing burst light detection of the incoming optical fiber when the incoming optical fiber is connected to the optical splitter port and when the incoming optical fiber is placed in the optical fiber bending module, and sending the burst light detection result to the analysis terminal when the burst light detection unit obtains the burst light detection result; and performing return loss measurement when the incoming optical fiber is unplugged from the optical splitter and inserted into the return loss measurement access port, and sending the connection judgment result to the analysis terminal when the return loss measurement unit obtains the judgment result of whether the incoming optical fiber is connected to the optical modem according to the reflectivity value;

[0098] The analysis terminal is used for, when receiving the burst light detection result, when the burst light detection result is that there is a burst light signal in the household optical fiber, determining that the household optical fiber is connected to the optical modem, recording the optical splitter port connected to the household optical fiber as being in use, and uploading it to the resource management center; and when receiving the connection judgment result, determining the household optical fiber whose connection judgment result is that the optical modem is not connected as a virtually occupied port optical fiber, updating the optical splitter port connected to the virtually occupied port optical fiber to the virtually occupied state, and uploading it to the resource center, determining the household optical fiber whose connection judgment result is that the optical modem is connected as being in access state, updating the optical splitter port connected to the household optical fiber to the in-use state, and uploading it to the resource center;

[0099] The resource center is used to store the status of all splitter ports.

[0100] The analysis terminal may be specifically an APP application on a smart mobile terminal such as a mobile phone or a tablet computer. In addition to status judgment and data forwarding, the analysis terminal may also realize functions such as analysis and statistics to facilitate viewing of the status of the splitter port, and may also receive data or instructions issued by the resource center, for example, viewing all the splitter ports in the virtual occupied state, cleaning up the household optical fiber connected to the splitter ports in the virtual occupied state, updating the splitter ports to the available state, and then reporting to the resource center, etc. In addition to storing the status of all splitter ports, the resource center may also perform statistics and analysis on the status of all splitter ports, and send the status of the splitter ports to the analysis terminal, instructing to clean up the splitter ports in the virtual occupied state, etc.

[0101] It should be noted that, if conditions permit, the analysis terminal can also be integrated with the test device into one device, that is, corresponding hardware modules and software programs are added to the test device to achieve the functions that the analysis terminal can achieve.

[0102] It should be understood that the above embodiments and descriptions only describe the principles, main features and advantages of the present invention. Without departing from the spirit and scope of the present invention, the present invention may be subject to various changes and improvements, and these changes and improvements all fall within the scope of protection of the present invention.

Claims

1. A connection test device for an optical fiber and an optical modem, characterized in that: It includes an optical fiber bending module, a first photoelectric detection module, a signal amplifier, an ADC module, a timing control circuit, an FPGA control logic module, a return loss measurement access port, a laser, and a second photoelectric detection module. The FPGA control logic module includes a burst light detection unit and a return loss measurement unit, wherein: The optical fiber bending module is used to bend the household optical fiber into a preset radius, so that the optical signal transmitted in the household optical fiber leaks to the outer layer of the household optical fiber; The first photoelectric detection module is arranged near the optical fiber bending module and is close to the outer layer of the access optical fiber, and is used to detect the burst optical signal leaked from the outer layer of the access optical fiber and perform photoelectric conversion; The signal amplifier and ADC module are used to amplify the received electrical signal and perform digital conversion; The timing control circuit is used to perform envelope detection on the digital electrical signal of the burst optical signal to obtain a complete pulse of the burst optical signal; The burst optical detection unit is used to calculate the pulse interval between the complete pulses of the burst optical signal detected by the timing control circuit within a preset time period, and calculate the average value of all complete pulses according to the pulse interval. If the average value is greater than the preset ratio of the noise signal, it is determined that there is a burst optical signal in the home optical fiber, otherwise it is determined that there is no burst optical signal in the home optical fiber; The return loss measurement access port is used to access the home optical fiber; The laser is used to emit laser light to the connected household optical fiber; The second photoelectric detection module is used to receive the echo signal reflected back by the emitted laser and convert it into an electrical signal; The return loss measurement unit is used to receive the digital electrical signal of the echo signal obtained after being processed by the signal amplifier and the ADC module, calculate the reflectivity value of the echo signal according to the following formula, and judge whether the home optical fiber is connected to the optical modem according to the reflectivity value: RL=RL ref -(P onu -P ref ) Where RL is the reflectivity value of the echo signal, RL ref is the preset reference reflectivity, P onu is the peak reflected power of the echo signal, P ref is the preset reference reflected power peak value.

2. The optical fiber and optical modem connection test device according to claim 1, characterized in that: The first photoelectric detection module includes two photoelectric detectors. A filter film is coated on the window of each photoelectric detector. The filter film only passes the burst optical signals with wavelengths of 1270nm and 1310nm, and isolates the optical signals with other wavelengths.

3. The optical fiber and optical modem connection test device according to claim 1, characterized in that: The device also includes a display screen, an MCU and a key module. The display screen, the key module and the FPGA control logic module are respectively connected to the MCU. The MCU is used to receive a trigger signal sent by the key module, generate corresponding instructions and send them to the corresponding module, and display the judgment results and other test results of the FPGA control logic module on the display screen.

4. The optical fiber and optical modem connection test device according to claim 1, characterized in that: The return loss measurement unit specifically includes: A receiving subunit, used for receiving the digital electrical signal of the echo signal obtained after being processed by the signal amplifier and the ADC module; The reflected power peak value calculation subunit is used to calculate the reflected power peak value P of the echo signal according to the echo signal digital electrical signal. onu ; The reflectivity calculation subunit is used to calculate the reflectivity value of the echo signal according to the following formula: RL=RL ref -(P onu -P ref ) The judgment subunit is used to judge whether the access optical fiber is connected to the optical modem according to the reflectivity value according to the following rules: When RL≥the first preset threshold, the access optical fiber is not connected to the optical modem; When the second preset threshold ≤ RL ≤ the first preset threshold, the access optical fiber is connected to the optical modem; When RL≤the second preset threshold, the fiber entering the home is broken.

5. The method for testing the connection between an optical fiber and an optical modem according to claim 4, characterized in that: The first preset threshold is -20dBm, and the second preset threshold is -40dBm.

6. The optical fiber and optical modem connection test device according to claim 1, characterized in that: The timing controller synchronizes the uplink time slot interval to 125us when performing envelope detection.

7. The optical fiber and optical modem connection test device according to claim 1, characterized in that: The second photoelectric detection module is specifically an avalanche photodiode.

8. A method for testing the connection between an optical fiber and an optical modem, characterized in that: The method is implemented based on the test device described in claim 1, and the method specifically comprises the following steps: S1. Establishing a communication connection between the analysis terminal and the test device according to claim 1; S2. When the incoming optical fiber is connected to the optical splitter port, the incoming optical fiber is placed in the optical fiber bending module to perform burst light detection on the incoming optical fiber. When the burst light detection unit obtains the burst light detection result, the burst light detection result is sent to the analysis terminal. S3, when the burst light detection result shows that there is a burst light signal in the incoming optical fiber, the analysis terminal determines that the incoming optical fiber is connected to the optical modem, records the splitter port connected to the incoming optical fiber as in use, and uploads it to the resource management center, otherwise, executes step S4; S4, unplug the household optical fiber from the optical splitter, and insert it into the return loss measurement access port to perform return loss measurement. When the return loss measurement unit obtains a judgment result of whether the household optical fiber is connected to the optical modem according to the reflectivity value, the connection judgment result is sent to the analysis terminal; S5, the analysis terminal determines that the incoming optical fiber with a connection judgment result of not being connected to the optical modem is a virtually occupied port optical fiber, updates the optical splitter port connected to the virtually occupied port optical fiber to a virtually occupied state, and uploads it to a resource center; determines that the incoming optical fiber with a connection judgment result of being connected to the optical modem is in an access state, updates the optical splitter port connected to the incoming optical fiber to an in-use state, and uploads it to a resource center; S6. The resource center stores the status of all splitter ports.

9. The method for testing the connection between an optical fiber and an optical modem according to claim 8, characterized in that: The method further comprises: The analysis terminal stores, counts and analyzes the status of the optical splitter port.

10. A connection test system between an optical fiber and an optical modem, characterized in that: The device comprises the test device, analysis terminal and resource center as claimed in claim 1, wherein: The test device is used for performing burst light detection of the incoming optical fiber when the incoming optical fiber is connected to the optical splitter port and when the incoming optical fiber is placed in the optical fiber bending module, and sending the burst light detection result to the analysis terminal when the burst light detection unit obtains the burst light detection result; and performing return loss measurement when the incoming optical fiber is unplugged from the optical splitter and inserted into the return loss measurement access port, and sending the connection judgment result to the analysis terminal when the return loss measurement unit obtains the judgment result of whether the incoming optical fiber is connected to the optical modem according to the reflectivity value; The analysis terminal is used for, when receiving the burst light detection result, when the burst light detection result is that there is a burst light signal in the household optical fiber, determining that the household optical fiber is connected to the optical modem, recording the optical splitter port connected to the household optical fiber as being in use, and uploading it to the resource management center; and when receiving the connection judgment result, determining the household optical fiber whose connection judgment result is that the optical modem is not connected as a virtually occupied port optical fiber, updating the optical splitter port connected to the virtually occupied port optical fiber to the virtually occupied state, and uploading it to the resource center, determining the household optical fiber whose connection judgment result is that the optical modem is connected as being in access state, updating the optical splitter port connected to the household optical fiber to the in-use state, and uploading it to the resource center; The resource center is used to store the status of all splitter ports.

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