KR0160805B1 - Optical connector for trouble tracking in the catv system - Google Patents

Abstract

The present invention uses the test function of the optical CATV field tester to find the disconnection or deterioration of the optical cable, optical connector of the optical CATV subscriber distribution network, and the failure point tracking test of the field tester for the optical CATV to find the abnormality of the optical module. The system is related to the failure points by testing the disconnection of the optical line and the abnormality of the optical module by section through the optical connector connection point. However, by adding the following functions, the test method can be further added to increase the reliability of the test and to enable convenient testing.

Description

Optical test device for field test for tracking the location of optical cable TV system

1 is a diagram illustrating a hardware structure of an embodiment of an optical connection device for a field test according to the present invention.

2 is a structural diagram of a subscriber distribution network of an optical CATV system according to the present invention.

3 is an optical transmission module test configuration diagram of a subscriber premises device according to the present invention.

4 is a light receiving module test configuration of the subscriber indoor device according to the present invention.

5 is an optical transmission module test configuration diagram of a subscriber access device according to the present invention.

6 is a light receiving module test configuration of the subscriber access device according to the present invention.

7 is an optical cable test configuration in an optical terminal box and an optical distribution box according to the present invention.

* Explanation of symbols for main parts of the drawings

1: subscriber access device 2: subscriber premises device

3: optical cable 4: optical connector

5: optical receiving module 6: optical transmitting module

7: optical connection device for field tester 8: light emitting diode

9: test signal generator 10: clock generator

11: clock regenerator 12: clock counter

13: Receive Data Analyzer 14: PC Interface

Field of the Invention The present invention finds the disconnection or deterioration of the optical cable and optical connector of the optical CATV subscriber distribution network using the test function of the optical CATV field tester, and the field for tracking the fault location of the optical CATV system for detecting the abnormality of the optical module. It relates to a test optical connection device.

Conventional field testers, such as optical power meter to measure the attenuation or return loss, or display the value according to the position, but these are basically simple equipment such as optical power meter was just a simple equipment.

In general, the central station of the optical CATV system, each center within the distribution center and the head end are developed to have a function of generating performance monitoring response signals or information so that they can be received and received from a central maintenance center located in the central station through the maintenance communication system. By processing, it is possible to quickly detect the abnormality of each device.

However, the subscriber distribution network is composed of optical cables, optical connectors, optical distribution boards, optical terminal boxes, and subscriber premises, starting from the subscriber connection device of the distribution center, and occupying the largest portion of the optical CATV system. The optical cable, optical connector and optical module part of are combined with active element and passive element so that alarm cannot be generated by itself. In addition, the subscriber distribution network is installed in the basement and the ground of the outdoor, so that the number of failures is much higher than that of other devices. Therefore, once the fixation occurred, there was a serious problem that it was very difficult to track down the location of the distribution network and the optical module when an on-site maintenance agent was dispatched for the actual maintenance.

Therefore, the present invention devised to solve all the problems of the prior art, the field tester is required to test the abnormality of the optical cable or optical connector and the optical module of the subscriber distribution network basically does not provide in the system itself. Use the test function of the optical CATV field tester to find the disconnection or deterioration of the optical cable, optical connector of the optical CATV subscriber distribution network, and the optical cable to detect the abnormality of the optical module. It is an object to provide an optical connection device.

In order to achieve the above object, the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a structural diagram of an embodiment of a field tester optical access device according to the present invention, FIG. 2 is a structural diagram of a subscriber distribution network of an optical CATV system, and FIG. 3 is a test configuration of an optical transmission module of a subscriber premises device. FIG. 5 is a test configuration diagram of an optical receiver module of a subscriber indoor device, FIG. 5 is a test configuration diagram of an optical transmission module of a subscriber access device, FIG. 6 is a test configuration diagram of an optical reception module of a subscriber connection device, and FIG. 1 is a subscriber connection device, 2 is a subscriber premises device, 3 is an optical cable, 4 is an optical connector, 5 is an optical reception module, 6 is an optical transmission module, and 7 is an optical connection for a field tester Device, 8 is a light emitting diode, 9 is a test signal generator, 10 is a clock generator, 11 is a clock regenerator, 12 is a clock counter, 13 is a receiving data analyzer, and 14 is a PC interface.

Explain the failure location tracking test method of the optical subscriber distribution network using the field tester, the test method of the field tester optical access device, the connection and test procedure with the subscriber premises equipment, the indication of the abnormality of the subscriber premises equipment, and the determination of the abnormality of the optical module. Method, test for abnormality of optical transmission module of subscriber indoor equipment, test for abnormality of optical reception module of subscriber indoor equipment, connection and test procedure with subscriber connection, test of optical transmission module of subscriber access equipment, optical reception module of subscriber access equipment Test, connection and test procedure of optical cable in optical terminal box and optical distribution box.

First, a failure location tracking test method of the field tester is required for tracking the failure location caused by the disconnection or deterioration of the optical cable and the optical connector and the failure of the optical module.

The optical path of the subscriber distribution network of the optical CATV system is connected with the optical cable (3) from the subscriber connection device (1) of the distribution center to each subscriber premises (2) as shown in FIG. 2, and the optical cable is the optical distribution box and the optical terminal. It is connected to the optical connector via the optical connector connection point 4 of the enclosure. The point where the field tester can be connected for the fault tracking test is limited to the optical connector connection point. Therefore, the test of the failure symptom is carried out by section at the optical connector connection point, and the optical subscriber distribution network failure location tracking test system adopting the accompanying test method is the configuration of the present invention.

The fault location tracking test method using the field tester is classified into the first test method of optical transceiver module of subscriber equipment, the second test method of optical transceiver module of subscriber access equipment, and the test method of disconnection of third optical fiber.

First, in order to test the subscriber indoor device optical module, the field tester is connected to the optical connector connection point of the subscriber indoor device as shown in FIG. 3 and FIG.

Second, in order to test the optical module of the subscriber access device, it is tested by connecting the field tester to the optical connector connection point of the subscriber access device as shown in FIG. 5 and FIG.

Third, the field tester is connected to the optical connector connection point connected to the optical distribution box or the optical terminal box of FIG. 7 to test the optical path. Detailed test procedure is as follows.

The test technique and hardware structure using the optical test device for field test of FIG. 1 is to connect the optical test device of the field tester to the optical connector 4 of the subscriber distribution network under test to test the disconnection of the optical cable and the optical connector. When the light source, the test signal source, passes through the optical cable or optical connector, the presence or absence of the optical signal is detected by the optical receiving module 5 in the field tester connected to the opposite side. To judge. In addition, in order to test the abnormal condition of the optical module under test, by connecting the field tester to the connection point of the front end of the optical module set to the light source state of the subscriber device, the presence or absence of failure of the optical transmission module under test is tested by testing the presence of the optical signal in the field tester. To judge. Abnormality of the light receiving module to be tested can be achieved by setting the field tester to the state of the test signal light source (6) and checking the status value of the receiving device at the field tester through the serial communication channel or confirming it through the LED (8). Do. For this test function, the field tester has an optical connection device board 7 as shown in FIG. 1, and has an optical transmission module, a test signal generator 9 and a clock generator 10 to operate as a test light source, and an optical signal. The optical receiving module 5, the clock regenerator 11, the clock counter 12, and the reception data analyzer 13 are required to detect the presence and the presence of the optical signal. It also consists of an interface 14 with operator interface software implemented on a PC.

And, the operator connection device is a PC, and displays the light transmission and reception state of the field tester, and when connected through the subscriber premises device and the PC serial channel can display the light transmission and reception status of the subscriber premises device. In the case of connection and test procedures with subscriber premises equipment, test circuits are constructed as shown in Figs. 3 and 4 to test the optical transceiver of subscriber premises and are tested according to the following procedure.

As an optical module abnormality determination method, the abnormality of the subscriber premises equipment is connected to the serial communication channel as shown in FIG. 3 and FIG. 4 through the serial communication channel 15 to indicate the abnormality of the optical transmission / reception module of the subscriber premises equipment. Just do it.

In order to test the abnormality of the subscriber premises equipment and the optical transmission module, if the field tester is connected with the serial communication channel 15, the abnormality of the optical module is directly displayed from the subscriber premises equipment to the field tester, and through the test optical cable Since the tester itself displays the presence of an optical signal, it is possible to immediately grasp the abnormality of the optical transmission module of the subscriber premises equipment. When the optical receiver module is connected as shown in Fig. 4, LOS is generated in the subscriber's premises and the optical transmitter and the optical receiver of the field tester are directly connected to the optical connector to check the optical transmitter / receive module and the abnormality of the field tester. If the test results of the field tester and the optical transmitting / receiving module of the field tester show no abnormality by the self test, it is determined that the optical receiving module of the subscriber premises equipment is abnormal. The abnormality of the subscriber indoor device is determined by the abnormality of the optical transmission module and the abnormality of the optical receiving module.

In the test of abnormality in the optical transmission module of the subscriber indoor device, the field tester receives the uplink optical signal 16 transmitted through the optical cable from the subscriber indoor device as shown in FIG. 3 and checks the presence or absence of the optical signal in the field tester. Receives the status signal of the optical transmission module 17 of the subscriber indoor device over the serial communication channel 15 to indicate the failure of the optical transmission module of the subscriber indoor device to indicate that the optical connector or the optical connector in front of the optical module You can check the cause of the failure of the optical cable. If there is no abnormality in the optical transmission module displayed through the serial communication channel 15 of the field tester, but it is determined that there is no optical signal received through the field tester optical cable, it is determined that the optical connector or the optical cable 18 in front of the optical module is abnormal. do. However, if it is indicated as an optical transmission module error through the serial communication channel 15, it is an error of the optical module.

This test is possible only if the downlink optical signal 19 in normal operation is received from the optical terminal box. This is because, even if there is no downlink light signal or abnormal, since the uplink light signal 16 is blocked in the subscriber premises for power saving, the test is not possible. Therefore, when the signal 19 is not normal, the test should be performed after the failure recovery by first performing the downlink disconnection test in the subscriber equipment.

And, in the test of the optical receiver module abnormality of the subscriber premises equipment, the field tester transmits a test optical signal to the subscriber premises equipment as shown in Figure 4, the subscriber premises equipment optical reception module 20 receives the generated signal to generate a status signal In addition, the field tester receives the status signal of the optical receiving module 20 of the subscriber premises device through the serial communication channel 21 to indicate the failure of the subscriber premises device to determine the cause of the failure. In addition, it is possible to check whether there is a failure of the optical receiving module as an indication of the LED 8 of the subscriber premises device. If LOS appears on the optical receiver module of the subscriber's premises, the optical receiver module may be in an abnormal state. However, it is necessary to confirm in advance that the test cable and the connector are intact through the self test of the field tester.

When testing the optical receiver module 20 in the subscriber premises, the field tester judges that it is not a normal downlink signal that can be recognized by the subscriber premises even though the field tester transmits an optical signal. Does not occur.

For testing the optical transmitter and receiver of subscriber access equipment, test circuit is composed as shown in Fig. 5 and Fig. 6 and tested according to the following procedure.

In the optical transmission module test of the subscriber access device, the field tester can be connected as shown in FIG. 5 to receive the optical transmission signal transmitted through the optical cable from the subscriber access device, and to indicate the presence of the optical signal to confirm the failure. If it is determined by the field tester that there is no received optical signal, there is an error in the optical transmission module 23 of the subscriber connection device.

In the optical receiving module test of the subscriber access unit, the field tester connects as shown in FIG. 6 and transmits an optical signal to the subscriber access unit, and the subscriber access unit optical receiving module 24 receives this to display a status signal or display an LED ( 8), field test personnel can check the cause of the failure of subscriber access device.

In the connection and test procedures of the optical terminal box and the optical cable in the optical distribution box, the optical connector box or optical distribution box 25 is connected to the optical connector connection point of the optical cable in the direction of the subscriber premises (2) and the subscriber connection device (1). As shown in FIG. 7, the items that can be tested by accessing the field tester are tests performed by indicating the presence or absence of the received optical signal and confirm whether the failure direction is an optical cable in the direction of the subscriber premises or the subscriber access device. At this time, the optical signal test is judged only by the status of abnormality appearing in the optical receiver 26 itself of the field tester, and the serial communication channel is not used because there is no connection.

The present invention as described above tracks the location of the failure by testing the disconnection of the optical line and the abnormality of the optical module for each section through the optical connector connection point. However, by adding the following functions, the test method can be further added to increase the reliability of the test and to enable convenient testing.

In other words, by adding optical power meta function, it is possible to increase the reliability of the test by adding the test method for each section, and by adding the OTDR (Optical Time Domain Reflector meter) function, it is possible to measure the disconnection position of the entire line of light at the point. The added convenience is that the function can measure the fault location, which is the disconnection position of the optical line, without having to travel to various places.

By using the field tester of the optical CATV system, this test technique can quickly find and repair the fault location of the optical subscriber distribution network and the optical module part, and the fault location can be tracked in the same way in other optical communication lines.

Claims (9)

An optical test apparatus for field testing for tracking a fault location of an optical cable TV system, comprising: optical transmitting means connected to an optical connector and an optical cable to operate as a test light source, and connected to the optical transmitting means to generate a test signal Optical transmission means for determining whether there is an abnormality of the optical transmission means, comprising a test signal generation means and a clock generation means connected to the test signal generation means; Optical receiving means connected to the optical connector and optical cable to detect the presence of an optical signal and to determine the presence of the optical signal, a clock reproducing means connected to the optical receiving means, a clock counter connected to the clock reproducing means, Optical receiving means having received data analyzing means connected to the clock counter; And a connecting means connected to the optical transmitting means and the optical receiving means to connect with an operator connecting device. In the subscriber distribution network of the optical CATV system connected to the optical connector from the subscriber connection unit of the distribution center to each subscriber premises, the optical cable is connected to the optical connector through the optical connector connection point of the optical distribution box and the optical terminal box. The internal transmitter is connected to the optical connector connection point of the optical receiving means in the subscriber's premises which receives the downlink optical signal through the optical path, and the connection point of the optical transmission fishery is connected to the optical connector connection point of the optical receiving means of the optical connection device for the field test. For the field test for the fault location tracking of the optical cable TV (CATV) system for testing the abnormality of the subscriber premises equipment through the serial communication channel between the field test optical connection device and the subscriber premises equipment Optical connection device. The optical receiving module receives the test optical signal from the field test optical connection device and generates a status signal, and the field tester optical connection device receives a status signal from the optical reception module of the subscriber indoor device through the serial communication channel. The optical connection device for the field test for tracking the fault location of the optical cable TV system, characterized in that for testing the optical reception module of the subscriber premises device. [4] The optical connection device for field test for tracking the location of a failure of an optical cable TV system according to claim 3, wherein the light emitting diode indicates a failure of the optical reception module of the subscriber premises device. In the optical cable TV (CATV) system for receiving the optical transmission signal transmitted from the field test optical connection device to the optical transmission module through the optical cable in the subscriber connection device and indicating the presence or absence of the optical signal to test the optical transmission module of the subscriber connection device. Field test optical connection for fault location tracking. The optical connection device for a field test for fault location tracking of an optical cable TV system according to claim 5, wherein the light emitting diode indicates whether the optical transmission module of the subscriber connection device is faulty. Optical cable, characterized in that for transmitting the optical signal from the optical connection device for the field tester to the subscriber connection device, receiving the optical signal from the optical reception module in the subscriber connection device to display the status signal to test the optical reception module of the subscriber connection device Optical connection device for field test for fault location tracking of TV (CATV) system. The optical cable TV (CATV) according to claim 7, wherein a light emitting diode (LED) 8 of the subscriber access device 1 is used to check whether the optical receiving module 24 has a failure. Field test optical connection for tracking the fault location of the system. In the optical terminal box 25, the optical tester 7 for the field tester is connected to the optical connector connection point of the optical cable in the direction of the subscriber premises device 2 and the subscriber connection device 1 to indicate whether or not the received optical signal is received. An optical connection device for field tests for tracking the fault location of an optical cable TV system, characterized in that configured to test a terminal box (25).