JP3045288B2 - Method of stopping optical signal output and its circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a circuit for transmitting an optical burst signal comprising a parent device, a plurality of terminal devices, and a transmission line including an optical branch connecting them.

[0002]

2. Description of the Related Art As a conventional related art, Japanese Patent Application No. 63-58.
No. 075. The configuration is shown in FIG. The outline of the optical transmission system according to this technology is that when an optical signal from a partner station is detected, accident detection information is transmitted to the partner station, and the partner station stops the output of the laser light emitting element based on the accident detection information. Thus, a failure due to a laser beam is prevented and safety is improved.

This embodiment will be described with reference to the drawings. FIG. 4A is a block diagram of the optical transmission device of the present example. FIG.
(B) is a block diagram of a station of the optical transmission device of the present invention. 4A and 4B, in the optical transmission device, two stations 10 connected by a pair of optical fiber cables 20 each transmit an optical transmission signal c to a partner station via one optical fiber cable. And a laser light receiving element 12 which receives an optical reception signal a from the other station via the other optical fiber cable and converts it into an electric signal.
And an optical transmission and reception circuit 30.

[0004] The optical transmitting and receiving circuit 30 includes a multiplexing unit 31 for inputting and multiplexing electric signals of a plurality of channels, and a multiplexing unit 3.
1 includes a drive control unit 32 that drives the laser light emitting element 11 by inputting the output of the first unit, an amplifier 33 that amplifies the output of the laser light receiving element 12, and a separator 34 that separates the output of the amplifier 33 into a plurality of channels. .

The feature of the present embodiment is that the optical transmission / reception circuit 30 detects that the optical reception signal a from the partner station has ceased based on the output of the demultiplexer 34 and multiplexes the accident detection information b. Detection unit 35 as one of multiple inputs to the multiplexing unit 31 and laser emission prevention for inputting the accident detection information of the partner station from the separation unit 34 as laser emission prevention means and providing the laser emission prevention signal d to the drive control unit 32 And a drive stopping unit of the drive control unit 32 for stopping the drive by cutting off the power of the laser light emitting element based on the laser emission prevention signal d.

[0006] The purpose of the invention is different between the above-described known example and the present invention. That is, a known example is protection of an operator against a failure caused by a laser beam, whereas the present invention is to maintain good transmission characteristics. Further, in the known example, the light emission control of the own station is performed based only on the information sent from the partner station, whereas in the present invention, the optical transmission stop signal sent from the parent device and the optical input of the terminal device are cut off. There is a difference in configuration in that the light emission control of the own terminal is performed by an optical input disconnection signal which detects and outputs a certain state.

[0007] As other related known examples, there are JP-A-4-345219, JP-A-8-97773, and JP-A-8-251102.

[0008]

In an optical burst signal transmission system in which a transmission path is constituted by optical branches (1: n), a device on the terminal side for transmitting a burst signal transmits at a timing other than the transmission timing. In such a case, normal data from another terminal device may be interrupted.

[0009] An object of the present invention is to provide a method for controlling the optical output stop from the parent device to the terminal device in a case where the terminal device cannot be controlled due to an error in the reception clock or an error in detecting the optical transmission stop signal. And when the optical input to the terminal device is interrupted, the power supply to the E / O module is stopped and the E / O
It is an object of the present invention to stop light emission of a module and prevent an optical signal from another terminal device from being affected, thereby maintaining good transmission characteristics.

[0010]

SUMMARY OF THE INVENTION An optical signal output stopping method according to the present invention is an optical burst signal transmission circuit comprising a master device, a plurality of terminal devices, and a transmission line including an optical branch connecting these devices. A method for stopping output of an optical signal from a terminal device when an abnormality occurs, wherein the parent device detects a terminal device abnormality, and the parent device includes an “optical transmission stop signal” in transmission data to the abnormal terminal device. The terminal device receives the "light transmission stop signal" and stops the light transmission, monitors the terminal E / O module for abnormal light emission, and detects the presence of the abnormal light emission. Then, a first system of optical signal output suspension including a step of shutting off the power supply to the E / O module, a step of detecting the "light input interruption" by the terminal device, and a signal transmitted as a result of the detection Disconnection detection signal ”to the E / O module. Source comprising a second system of optical signal output stop comprising the steps of the disconnection of the supply.

Further, the circuit for stopping the output of the optical signal according to the present invention comprises:
An optical burst signal transmission circuit comprising a parent device, a plurality of terminal devices, and a transmission line including an optical branch connecting them, wherein the E / O converts an optical signal from the parent device into electricity and outputs received data. A module (1), an E / O module (3) for converting an electric signal from the terminal device into light and outputting the light, and an optical input disconnection detection for outputting a disconnection detection signal when the terminal device detects an optical input disconnection state. Means (7), optical transmission stop signal detecting means (2) for transmitting an optical transmission stop signal for detecting an optical transmission stop signal from received data from the parent device, and transmission selecting means (4) for controlling a transmission burst signal. If the terminal device transmits an optical transmission stop signal based on data received from the parent device, a monitor means (5) for monitoring abnormal light emission of the E / O module (3) itself; ) For power supply Power supply unit for supplying and a (6).

[0012] In another embodiment of the present invention, the power supply unit stops supplying power to the E / O module when receiving the optical input disconnection signal from the optical input disconnection detection unit.

Further, even when the optical transmission stop signal detecting section sends out the optical transmission stop signal to stop the data transmission to the E / O module, the power supply section outputs the E / O signal when the optical output is not stopped. Stopping the power supply to the O module is also an embodiment included in the present invention.

In the normal state, the transmission selection means passes the transmission burst signal as it is and inputs it to the E / O module. However, when the optical transmission stop signal is received, the transmission selection data is fixed to the optical output stop side. Is one embodiment.

Further, in one embodiment, when the monitor means detects abnormal light emission of the E / O module, it sends a power control signal to a power supply unit.

[0016]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a configuration block diagram showing an embodiment of the present invention. FIG. 1A shows a system including a parent device and a plurality of terminal devices. In the present invention, a transmission path is configured by such optical branching (1: n).
A plurality of terminal devices are connected to the base by optical branching, and the downstream signal (parent device → terminal device) is applied to an optical burst signal transmission system in which an optical continuous signal is transmitted, and the upstream signal (terminal device → parent device) is an optical burst signal. Is done. In such a system, when a device on the terminal side transmitting an optical burst signal performs transmission at a timing other than the transmission timing, transmission of normal data of another terminal device may be interrupted.

FIG. 1B is a block diagram showing a configuration of a terminal device of the optical transmission device. In the receiving unit of the terminal device, 0
The / E module 1 converts the optical signal 11 from the parent device into an electric signal and extracts the received data. Here, an optical input disconnection detecting unit 7 for detecting the reception disconnection of the optical signal is provided. When detecting an abnormality in the terminal device, the master device transmits a signal including an optical transmission stop signal to the terminal device. When the terminal device receives the optical transmission stop signal, the optical transmission stop signal detector 2 detects this. Thus, a transmission selection unit 4 for stopping data transmission to the E / O module 3 is provided.

Even in the above case, it is conceivable that the optical transmission is continued without being stopped due to an error in the reception clock or an error in detecting the optical transmission stop signal. For this reason, a monitor unit 5 for monitoring the optical output of the E / O module is provided. The power supply unit 6 that supplies power to the E / O module stops the supply of power to the E / O module and cuts off the light output in the case of the light input interruption or abnormal light emission of the E / O module. The configuration is as follows.

Next, the operation will be described in more detail mainly.
FIG. 2 is a flowchart showing this flow. FIG.
The timing chart of the signal exchange is shown in FIG.

On the optical receiving side of the terminal device, the optical signal 11 from the parent device is received by the 0 / E module 1, converted into electricity, and the received data 12 is output. Here, when the optical input disconnection detecting unit 7 inside the terminal device detects an abnormal state in which the optical input of the terminal device is disconnected, the optical input disconnection signal 21 is transmitted. When the power supply unit 6 receives the optical input disconnection signal 21, the power supply to the terminal E / O module is disconnected.
As a method of detecting the interruption of the light input, there is the following detection method.

In normal data transmission, the ratio of 1/0 is set to be half, but when the optical input is interrupted, the received data is fixed. That is, it is detected that "1" or "0" has continued for a certain time or longer.

Alternatively, a specific pattern is periodically transmitted from the parent device, and this pattern is checked by the terminal device. When the optical input is interrupted, the specific pattern cannot be received, so that an abnormality can be detected.

Further, any method such as detecting that the clock cannot be normally reproduced from the received optical signal may be used.

Next, identification of an abnormal terminal when an abnormality is detected in the above-mentioned parent device (step 101) will be described.

In the case of a minor failure in which only the received signal from a certain terminal device is abnormal for the parent device, an optical transmission stop signal is transmitted only to the abnormal terminal device to eliminate the influence on other signals. it can.

When a serious failure that affects all systems occurs, it is not possible to simply identify an abnormal terminal. Send an optical transmission stop signal in order from the number,
For example, if the failure is recovered when the optical transmission stop signal is sent to the third terminal device, the third terminal device can be identified as abnormal.

When the abnormal terminal is specified in this way, the parent device transmits the transmission data to the abnormal terminal device including the optical transmission stop signal (step 102). Next, when the optical transmission stop signal detector 2 detects the optical transmission stop signal 20 from the received data 12 (step 103), the transmission selector 4 fixes the transmission burst data 13 to the optical output stop side. The transmission data 14 is sent to the E / O module 3 (step 103). More specifically, E /
The O module changes the light output level with respect to 1/0 of the input electric signal.

In the normal state, the transmission burst signal 13 passes through the transmission selector 4 as it is, is input to the E / O module, is converted into an optical signal 19, and is transmitted. When the optical transmission stop signal is detected, the transmission burst signal 13 is fixed to “1” or “0” by the transmission selection unit 4. The fixed polarity is the direction in which the E / O module stops optical output. The monitor unit 5 monitors the light 19 from the E / O module 3 at the time of outputting the optical transmission stop signal 20 by the monitor signal 15 (step 104), and the light is output during the fixed data transmission in which the optical signal is stopped. If so, the power supply control signal 16 is sent to the power supply unit 6 to stop supplying power to the E / O module (step 106).

That is, the power supply unit 6 normally supplies the power input 17 directly to the power output 18 for the E / O module.
Is supplied to the E / O module 3 when the power control signal 16 is received.
Is received (step 105), the power output 18 for the E / O module is stopped. Therefore, the present invention
The optical output of the E / O module is monitored and the interruption of the optical input is monitored, and if either of them occurs, the power supply to the E / O module is cut off.

[0030]

As described above, when an abnormality is detected, the parent device transmits an optical transmission stop signal in the transmission data to the abnormal terminal device, and the terminal device stops the optical transmission. However, when this control cannot be performed for the above-mentioned reason or when the optical input is interrupted, the power supply of the E / O module is turned off and the output of the light is stopped, so that abnormal light emission and light This has the effect of preventing the optical output at the time of input disconnection from affecting optical signals from other terminal devices.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of an optical signal output stop circuit of the present invention.

FIG. 2 is a flowchart illustrating an embodiment of a method for stopping optical signal output according to the present invention.

FIG. 3 is a timing chart showing exchange of signals.

FIG. 4 is a block diagram showing a configuration of a conventional example.

[Explanation of symbols]

 Reference Signs List 1 0 / E module 2 Optical transmission stop signal detecting unit 3 E / O module 4 Transmission selecting unit 5 Monitor unit 6 Power supply unit 7 Optical input disconnection detecting unit 11 Optical signal 12 Received data 13 Transmission burst signal 14 Transmission data 15 Monitor signal 16 Power control signal 17 Power input 18 Power output for E / O module 19 Optical signal 20 Optical transmission stop signal 21 Optical input cutoff signal

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-8-251102 (JP, A) JP-A-63-4733 (JP, A) JP-A-1-231438 (JP, A) JP-A-4- 345219 (JP, A) JP-A-8-97773 (JP, A) JP-A-5-14358 (JP, A) JP-A-63-164541 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04B 10/00

Claims (6)

(57) [Claims] An optical burst signal transmission circuit comprising a parent device, a plurality of terminal devices, and a transmission line including an optical branch connecting them, wherein a method of stopping an optical signal output from a terminal device when a terminal abnormality occurs. A step of detecting a terminal device abnormality from the parent device; a step of transmitting the optical device including an “optical transmission stop signal” in transmission data to the abnormal terminal device; Receiving the received light, stopping the transmission of light, monitoring abnormal light emission of the terminal E / O module, and shutting off the power supply to the E / O module when the presence of the abnormal light emission is detected. A first system of optical signal output suspension including: a terminal device detecting “optical input disconnection”; and an E / O by a “disconnection detection signal” transmitted as a result of the detection.
Shutting off the power supply to the module, and stopping the supply of power to the E / O module even if any of the systems is activated. How to stop optical signal output. 2. An optical burst signal transmission circuit comprising a master device, a plurality of terminal devices, and a transmission line including an optical branch connecting them, converts an optical signal from the master device into electricity and outputs received data. 0 / E module (1) and E / O for converting an electric signal from a terminal device into light and outputting the light
A module (3); an optical input disconnection detecting means (7) for outputting a disconnection detection signal when the terminal device detects an optical input disconnection state; and an optical transmission stop for detecting an optical transmission stop signal from data received from the parent device. An optical transmission stop signal detecting means (2) for transmitting a signal, a transmission selecting means (4) for controlling a transmission burst signal, and an optical transmission stop signal transmitted by the terminal device based on received data from the parent device. A light characterized by comprising a monitor means (5) for monitoring abnormal light emission of the E / O module (3) itself, and a power supply section (6) for supplying electricity as a power supply for the E / O module (3). Signal output stop circuit. 3. The optical signal output stop circuit according to claim 2, wherein the power supply unit stops supplying power to the E / O module when receiving the optical input disconnection signal from the optical input disconnection detection unit. 4. The power supply unit, when the optical output is not stopped even when the optical transmission stop signal detecting unit sends out the optical transmission stop signal and stops the data transmission to the E / O module. 4. The optical signal output stop circuit according to claim 2, wherein power supply to the O module is stopped. 5. The transmission selection means, in a normal state, passes a transmission burst signal as it is and inputs the transmission burst signal to an E / O module, but when receiving an optical transmission stop signal, fixes the transmission burst data to an optical output stop side. 5. The optical signal output stop circuit according to any one of 2 to 4. 6. The optical signal output according to claim 2, wherein said monitor means sends a power control signal to a power supply unit when abnormal light emission of the E / O module is detected. Stop circuit.