KR19990080282A - Automatic monitoring device for cutting point of light beam using wavelength division multiplexing - Google Patents

Abstract

The present invention relates to a device for automatically monitoring a beam cutting point using wavelength division multiplexing, comprising: a first optical transmission module, a test light control unit, a second optical transmission module, a first optical reception module, a wavelength division multiplexing unit, a beam splitter unit, and a monitoring unit It is made of wealth.

Among the components of the present invention, the first optical transmission module receives arbitrary data, outputs a corresponding communication optical signal, and outputs an LOS generation signal when the LOS state is detected. In addition, the test light control unit generates a predetermined test light control signal according to the LOS generation signal, the second optical transmission module generates a test light signal according to the test light control signal, and the wavelength division multiplexing unit outputs the communication output from the first optical transmission module. The optical signal and the test optical signal output from the second optical transmission module are wavelength-division multiplexed and output.

The beam splitter outputs the output signal of the wavelength division multiplexer to the optical path, or separates and outputs the test optical signal from the reflected optical signal reflected from the optical path, and the monitoring apparatus uses the test optical signal output from the beam splitter. It searches for the cutting point by the ray. On the other hand, the first receiving optical module receives the optical signal from the optical path, converts into an electrical signal and outputs.

By using the present invention, since the cutting location on the optical path can be known, it is possible to reduce the time and cost according to the maintenance and repair of the optical path, thereby enabling effective network management.

Description

A automatic monitoring unit of detecting disconnection points of optical fibers using wavelength division multiplexing

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a light beam surveillance system. In particular, wavelength division multiplexing is a device capable of detecting the occurrence of a break in an optical path constituting an optical communication network using a wavelength division multiplexing technology and automatically monitoring the point where the break occurred. The present invention relates to a device for automatically monitoring a cutting point of a light beam using the following (hereinafter referred to as an automatic monitoring device).

1 is a simplified schematic diagram of an optical communication network connected by an ATM switch, wherein each ATM switch 110 or 120 transmits and receives an optical signal through an optical line 130. ATM switch 110 and 120 and each subscriber can be connected using an existing coaxial cable, or can be connected by an optical cable, but most are still connected by a coaxial cable.

When a subscriber connected to the transmitting ATM switch 110 transmits data, the data is first received by the transmitting ATM switch 110, and this signal is converted into an ATM-based signal, which is converted into an optical signal and then converted into a light path. Transmitted via 130. This signal is received at the receiving ATM exchanger 120, converted into an electrical signal and finally delivered to the subscriber.

Therefore, each ATM switch 110 and 120 converts an ATM-based electrical digital signal into an optical signal and transmits the optical signal to the optical path 130, and when the optical path is cut at an arbitrary point on the optical path 130, the optical path 130, a device 200 capable of grasping the cutting situation is required.

The conventional optical beam cutting point inspection apparatus can only inspect whether there is a cut on the optical path 130. Thus, even if it is found out that there is a cut on the optical path 130, it was not possible to know where the cut occurred, and thus could not be quickly repaired, and there was a problem that the service through the corresponding optical path was delayed a lot.

Accordingly, the present invention has been made to solve the above problems, by using a wavelength division multiplexing technology to detect that the cutting occurs on the optical path 130 constituting the optical communication network, and also to the point where the cutting occurs automatically An object of the present invention is to provide a device for automatically monitoring a beam cutting point 200 using wavelength division multiplexing which is a device that can be monitored.

In order to achieve the above object, the automatic optical beam cutting point monitoring device using the wavelength division multiplexing according to the present invention, receives arbitrary data, outputs a corresponding communication light signal, LOS (Loss Of Signal) state A first optical transmission module configured to output an LOS generation signal when is detected; A test light control section for generating a predetermined test light control signal in accordance with the LOS generation signal; A second optical transmission module for generating a test light signal according to the test light control signal; A first receiving optical module which receives an optical signal from the optical path and converts the optical signal into an electrical signal and outputs the electrical signal; A wavelength division multiplexer for wavelength division multiplexing the communication optical signal output from the first optical transmission module and the test optical signal output from the second optical transmission module; A beam splitter unit for outputting the output signal of the wavelength division multiplexer to the optical path or separating and outputting a test optical signal from the reflected optical signal reflected from the optical path; And a monitoring device for searching for a cutting point of the light beam by using a test light signal output from the beam splitter unit.

On the other hand, the test light control unit includes a voltage regulator for generating a predetermined bias voltage as the test light control signal; And a pulse generator for generating a predetermined pulse signal.

The monitoring device may further include: a photodetector and an amplifier configured to receive a test light signal output from the beam splitter unit, detect a test light signal, and amplify and output the test light signal; An integrator that integrates and outputs an optical signal output from the photodetector and the amplifier; A counter for calculating a time starting from the time point at which the test light signal is output from the second optical transmission module; And a comparator for calculating a distance to the cutting point of the light beam by using the counter and the output signal of the integrator.

And, the counter may be configured to count the number of pulse signals generated by the pulse generator, to perform its role.

1 is a simplified schematic diagram of an optical communication network connected by an ATM switch;

2 is a block diagram of an automatic monitoring apparatus according to the present invention.

* Explanation of symbols for main parts of the drawings

110,120: ATM exchange 130: optical path

200: automatic monitoring device 210: first optical transmission module

220: test light control unit 221: voltage regulator

222: pulse generator 230: second optical transmission module

240: first optical receiving module 250: wavelength division multiplexer

260: beam splitter unit 270: monitoring unit

271: photodetection and amplifier 272: counter

273: Integrator 274: Comparator

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram of the automatic monitoring device 200 according to the present invention, the first optical transmission module 210, the test light control unit 220, the second optical transmission module 230, the first optical receiving module 240, The wavelength division multiplexer 250, the beam splitter 260, and the monitoring unit 270 are formed.

First, the operation of the automatic monitoring device 200 will be briefly described.

The electrical digital signal (input data) input from the transmitting ATM switch 110 to the automatic monitoring device 200 is converted into the corresponding optical signal through the first optical transmission module 210 and sent to the optical path 130. At this time, if LOS (Loss Of Signal) is generated with respect to the input data, the test light control unit 220 controls the second optical transmission module 230 to output high test light.

The test optical signal is wavelength-division multiplexed with the communication optical signal output from the first optical transmission module 210 and then sent to the optical path 130 through the beam splitter 260. This multiplexed optical signal sent to the optical path 130 is then reflected where the optical path is cut off. The test light signal from the reflected light signal is again received by the monitoring unit 270 through the beam splitter 260. The monitoring unit 270 examines the received test light signal, finds a cutting point, and sends the cut point to an upper processor of the ATM switch 110, or outputs it to a separate monitor device.

Now, each component of the automatic monitoring apparatus 200 will be described in detail.

The first optical transmission module 210 receives data (input data) to be transmitted from the ATM switch 110. At this time, the input data is an electrical digital signal. The input data is converted into an optical signal and then output. At the same time, the input data is checked to see if LOS has occurred. If the LOS is generated as a result of the input data test, a separate LOS detection signal is output.

The first optical receiving module 240 receives the optical signal transmitted from the other ATM exchanger 120 through the optical path 130, converts the optical signal into an electrical digital signal, and outputs the converted optical signal.

When the LOS detection signal is generated in the first optical transmission module 210, the test light control unit 220 sends a test light control signal to output the test optical signal to the second optical transmission module 230. The test light control signal is an arbitrary bias voltage signal and a pulse signal, and the test light control unit 220 includes a voltage regulator 221 for generating the above bias voltage and a pulse generator 220 for generating a pulse signal.

The second optical transmission module 230 receives the bias voltage and the pulse signal from the test light control unit 220 and outputs a high output light signal (test light signal). At this time, the output test light signal is different from the output light (communication light signal) of the first optical transmission module 210 and its wavelength.

The wavelength division multiplexing unit 250 receives the communication optical signal output from the first optical transmission module 210 and the test optical signal output from the second optical transmission module 230, and multiplexes the wavelength after splitting.

The multiplexed optical signal output from the wavelength division multiplexer 250 is incident to the optical path 130 through the beam splitter 260.

Meanwhile, the multiplexed optical signal incident on the optical path 130 travels along the optical path 130 and is reflected at the cut portion on the optical path 130. The reflected optical signal (reflected light signal) is returned back along the optical path 130 and is incident again to the beam splitter 260. The optical signal re-incident to the beam splitter 260 is a multiplexed optical signal having both a communication light signal and a test light signal, and the beam splitter 260 separates only the test light signal from the monitoring unit 270. Send to.

The monitoring unit 270 includes a photodetector and an amplifier 271, a counter 272, an integrator 273, and a comparator 274.

The test light signal separated from the beam splitter unit 260 is received by the photodetector and the amplifier 271. The received test light signal is detected through a photodiode or the like and then amplified and applied to the integrator 273. The integrator 273 performs photodetection and integration operations on the optical signal received from the amplifier 271. At this time, the output signal of the integrator 273 is rapidly changed at the moment of receiving the test light signal reflected from the cutting point on the optical path 130.

The counter 272 calculates a time t before returning to the monitoring unit 270 after the test light signal is output from the second optical transmission module 230. In this case, the counter 272 may input the pulse signal generated by the pulse generator 222 of the test light control unit 220 as an input, and count the number of pulses to perform the above time calculation.

The comparator 274 receives the current coefficient value from the counter 272 and the signal from the integrator 273, and the moment when the output signal of the integrator 273 changes abruptly is reflected on the cut line on the optical path 130. Since the test light signal is reached, the count value up to this time is examined and the time until the test light signal is output and returned is measured.

Then, as shown in Equation 1, the distance l from the transmitting ATM switch 110 to the cut point can be known.

Here, the speed means the light speed.

When the distance to the cutting point on the optical path 130 is calculated by the comparator 274, this distance signal (monitoring data) is transmitted to the upper processor of the ATM switch 110 to perform a necessary process or to perform a separate monitor. It will print to the device and notify the network administrator.

When using the automatic monitoring device 200 according to the present invention, it is possible to know not only whether the cutting situation occurred on the optical path 130, but also the location of the cutting, and according to the maintenance and repair of the optical path 130 and By reducing costs, effective network management is possible.

Claims (4)

A device for finding a cutting point on an optical path of an optical communication network, the apparatus comprising: receiving first data, outputting a corresponding communication light signal, and outputting an LOS generation signal when a LOS (Loss Of Signal) state is detected; Module 210; A test light control unit 220 for generating a predetermined test light control signal according to the LOS generation signal; A second optical transmission module 230 generating a test light signal according to the test light control signal; A first receiving optical module 240 which receives an optical signal from the optical path and converts the optical signal into an electrical signal and outputs the electrical signal; A wavelength division multiplexer 250 for wavelength division multiplexing the communication optical signal output from the first optical transmission module 210 and the test optical signal output from the second optical transmission module 230; A beam splitter unit 260 for outputting an output signal of the wavelength division multiplexer 250 to the optical path or separating and outputting a test optical signal from the reflected optical signal reflected from the optical path; And And a monitoring unit (270) for searching for a cutting point of the light beam by using the test light signal output from the beam splitter (260). The test light control unit (220) of claim 1, further comprising: a voltage regulator (221) for generating a predetermined bias voltage as the test light control signal; And And a pulse generator (222) for generating a predetermined pulse signal. 2. The apparatus of claim 1, wherein the monitoring unit 270 comprises: a photodetector and an amplifier 271 which receives a test light signal output from the beam splitter unit 260, detects, amplifies and outputs a test light signal; An integrator 273 for integrating and outputting the optical signal output from the photodetector and amplifier 271; A counter 272 for calculating a time starting from the time point at which the test light signal is output from the second optical transmission module 230; And Automatically cutting the optical beam cutting point using wavelength division multiplexing, characterized in that it comprises a comparator 274 for calculating the distance to the optical fiber cutting point using the output signal of the counter 272 and the integrator 273. Monitoring device. 4. The apparatus of claim 3, wherein the counter (272) is configured to count the number of pulse signals generated by the pulse generator (220) of claim 2.