JP2836639B2 - Optical line switching control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical line switching control device used for switching an optical fiber core in an optical fiber line section.

2. Description of the Related Art Conventionally, when an optical line is switched by using an optical switching element in a unit of a medium called an optical fiber core, a failure of the optical switching element before switching is not determined, and the optical transmission of the transmission device after the switching is performed. Post-judgment was performed based on a disconnection alarm or the like.

"Problems to be Solved by the Invention" However, in recent years, the information transfer capability of the transmission device has been improved, and switching failure due to a failure of the optical switching element makes it impossible to receive light on the receiving side, resulting in communication interruption. This causes the problem of a large amount of missing information. In addition, in actuality, it takes about one second until an alarm is generated in a post-judgment due to an optical interruption alarm of the transmission device after the switching of the optical line, and it is impossible to make a judgment immediately after the switching.

Therefore, in order to solve the above problems, it is necessary to introduce a new concept of failure determination of the optical switching element before switching and switching success / failure determination immediately after switching.

The present invention has been made in view of the above circumstances, and its purpose is to improve the reliability of optical line switching,
An object of the present invention is to provide an optical line switching control device that detects a failure of an optical switching element before switching, immediately after switching, or both.

Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 provides an optical switching element for switching an optical fiber by passing a switching current between switching terminals. And an optical line switching control device for transmitting a switching current between switching terminals of the optical switching element, wherein a failure determination current is used for switching the optical switching element before switching the optical fiber core. A circuit for transmitting a voltage between the terminals, a circuit for measuring a voltage between the switching terminals generated by the failure determination current, and a circuit for determining whether the optical switching element is normal or failed based on the magnitude of the voltage. It is characterized by having.

According to a second aspect of the present invention, there is provided an optical switching device in which a switching current is applied between switching terminals to perform a switching operation of an optical fiber core, and a resistance value between state detecting terminals changes according to an optical path state. In an optical switching system comprising an optical line switching control device for transmitting a switching current between a switching element and a switching terminal of the optical switching element and a state detecting current between the state detecting terminals, A circuit for sending between the switching terminals of the switching element and a switching current between the switching terminals of the optical switching element to perform an optical path switching operation, and then a state detection current between the state detecting terminals of the optical switching element. And a circuit for measuring the voltage between the state detection terminals generated by the state detection current, and determining whether the state of the optical switching element is the working side optical path or the standby side optical path based on the magnitude of the voltage. Circuit It is characterized in that there.

Further, according to a third aspect of the present invention, there is provided an optical switching device in which a switching current is supplied between switching terminals to perform a switching operation of an optical fiber core, and a resistance value between state detecting terminals changes according to an optical path state. In an optical switching system comprising an optical line switching control device for transmitting a switching current between a switching element and a switching terminal of the optical switching element and a state detecting current between the state detecting terminals, A circuit for sending between the switching terminals of the switching element, a circuit for sending a failure determination current between the switching terminals of the optical switching element before switching the optical fiber core, and a switching terminal generated by the failure determination current A circuit for measuring a voltage between the switching elements and a switching current is supplied between the switching terminals of the optical switching element to perform an optical path switching operation, and then a state detection current is transmitted between the state detecting terminals of the optical switching element. Circuit and current for state detection A circuit for measuring the voltage between the state detection terminals generated by the circuit, and the voltage between the switching terminals of the optical switching element generated by the failure determination current and the voltage between the state detection terminals generated by the state detection current Thus, it is characterized by comprising a circuit for determining the failure of the optical switching element and determining whether the state of the optical switching element is the working side optical path or the standby side optical path.

[Operation] According to the optical line switching control device according to claim 1, switching of the optical switching element is performed by a circuit that sends a failure determining current different from the switching current to the optical switching element before switching the optical fiber core. The voltage between the switching terminals of the optical switching element is measured by a circuit for measuring the voltage between the switching terminals by applying a current between the switching terminals, and the circuit for determining the voltage determines whether or not the voltage is a value when the optical switching element is normal. By determining whether the value is the value at the time of failure, it is possible to determine whether the optical switching element is normal or failed before switching.

According to the optical line switching control device of the second aspect, the switching current is supplied between the switching terminals of the optical switching element,
After performing the switching operation of the optical fiber, a state detection current is applied between the state detection terminals of the optical switching element, and the voltage between the switching terminals is measured by the circuit for measuring the voltage between the switching terminals. The switching operation is normally performed by measuring the voltage of the optical path and determining whether the voltage is a value when forming the working optical path or a value when forming the standby optical path by a circuit for determining the voltage. It can be determined whether or not it has been touched.

Further, according to the optical line switching control device of the third aspect, the switching terminal of the optical switching element is provided by a circuit for sending a failure determining current different from the switching current to the optical switching element before switching the optical fiber core. The voltage between the switching terminals of the optical switching element is measured by a circuit that measures the voltage between the switching terminals, and the voltage between the switching terminals of the optical switching element and the voltage between the state detection terminals are determined. The switching circuit determines whether the voltage of the optical switching element is normal or faulty, and determines whether the optical switching element is normal or faulty before switching, and outputs the state detection current after switching. The voltage between the terminals for detecting the state of the optical switching element is measured by a circuit that conducts between the terminals for detecting the state of the optical switching element and measures the voltage between the terminals for switching. The voltage is determined by the circuit that determines the voltage between the terminals. By determining whether the value at the time of forming the optical path of the values or pre-side at the time of forming a can determine whether the switching operation has been normally performed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram for explaining the outline of an optical switching system, where 11a and 11b are transmission devices, and 12a and 12b are disposed on an optical line between these two transmission devices 11a and 11b to switch the optical line. Optical switching elements, 13a, 13b are optical line switching control devices attached to these optical switching elements 12a, 12b, respectively, for controlling the optical switching elements 12a, 12b, and 14a is an optical line disposed between the optical switching elements 12a, 12b. The working optical fiber core 14b is a spare optical fiber core disposed between the optical switching elements 12a and 12b as a spare for the working optical fiber core, and 14c is the optical line switching control device 13a. , 13b are switching control optical fibers.

In FIG. 1, when a switching command is input to the optical line switching control device 13a or 13b, the physical path (light path) is switched from the optical switching element 12a to the working optical fiber core 14a to the optical switching element 12b. Element 12a → Spare optical fiber core 14
b → switched to the light switching element 12b.

FIG. 2 shows the optical switching element 12a or 12b and the optical line switching control device 13a or 13b in FIG. 1 in more detail. The optical line switching control devices 13a and 13b
a, 26b, a current sending circuit 21 for sending a failure determination current and a normal switching current, a voltage detection circuit 22 for detecting a voltage between the switching terminals 26a, 26b, and a switching terminal 26a, 26b. It comprises a voltage determination circuit 23 for determining a failure of the optical switching element 12a or 12b based on the magnitude of the voltage, a display 24 for displaying data, and a console 25.

Here, the current sending circuit 21 has a current sending function for failure determination and a current sending function for normal switching.
Even if each function is realized by an individual circuit, there is no problem. Similarly, the voltage determination circuit 23 has a failure determination trigger transmission function, a normal switching trigger transmission function, a command translation function, and an input command / execution result output function, but it goes without saying that it can be realized by individual circuits. . In this embodiment, this is realized by the central control circuit. The voltage detection circuit 22 is realized by an A / D (ANALOG TO DIGITAL) converter having a central control circuit compatible output, but can be realized by a group of comparators having different thresholds.

The output from the console 25 is supplied to a voltage determination circuit 23, which supplies the supplied command to the current sending circuit 21 or various information supplied from the voltage detection circuit 22. After a predetermined judgment is made, the display is displayed on the display 24.

In the optical line switching control device having the above configuration,
Before switching, the failure determination of the optical switching element 12a or 12b is performed according to the following flow.

First, a failure determination command is input from the console 25 to the voltage determination circuit 23. Here, the command for failure determination can be arbitrarily set by the command definition in the storage program resident in the voltage determination circuit 23.

Upon receiving the failure determination command, the voltage determination circuit 23 translates the content and sends a failure determination trigger to the current transmission circuit 21. The current transmission circuit 21 that has received the failure determination trigger transmits a failure determination current between the switching terminals 26a and 26b.

In this embodiment, since the optical switching element 12a or 12b has an actuator with an operating current of 1 amperage or more inside, 0.1 ampere, which is sufficiently smaller than 1 ampere, is set as the value of the failure determination current. Therefore, the optical switching element 12a or 12b does not perform the switching operation due to the failure determination current. Note that the failure determination current depends on the operation characteristics of the optical switching element, and is not limited to 0.1 amp.

Finally, the switching terminal 26 generated by the failure determination current
The voltage between a and 26b is measured by the voltage detection circuit 22, the voltage judgment circuit 23 makes a failure judgment, and the display unit 24 determines whether the optical switching element is normal or faulty. Is displayed.

Here, the failure types are shown in FIGS. 3 (a) and 3 (b).
FIG. 3A shows a short-circuit failure of the winding 31 of the actuator incorporated in the optical switching element 12a or 12b, and FIG.
Is a case where the winding part 31 of the actuator incorporated in the optical switching element 12a or 12b has a disconnection failure.

In the case of a short-circuit fault as shown in FIG. 3 (a), the voltage generated between the switching terminals 26a and 26b due to the fault determination current has a lower value than the normal voltage. Specifically, in the present embodiment, the winding portions of the actuators of the light switching elements 12a and 12b
Since the DC resistance of 31 is 24 ohms, it is 2.4 volts in normal operation, but less than 2.4 volts in short circuit.

In the case of a disconnection failure as shown in FIG. 3 (b), the input terminals of the voltage detection circuit 22 are sufficiently high.
The voltage generated between them becomes the power supply voltage of the current transmission path 21. In the present embodiment, an A / D converter having an input impedance of 1 MΩ or more is applied to the voltage detection circuit 22, and the current transmission circuit 2
The power supply voltage of 1 was 5 volts in order to effectively use the power supply of other circuits.

To summarize the determination criteria of this embodiment, the switching terminals 26a, 2
When the voltage generated at 6b is 2.4 volts, the optical switching element 12a or 12b is normal, and the voltage generated at the switching terminals 26a and 26b is
If the voltage is less than 2.4 volts, the optical switching element 12a or 12b is short-circuited, and if the voltage generated at the switching terminals 26a, 26b is 5 volts, the disconnection is broken.

Next, an embodiment of the optical line switching control device according to the second aspect of the present invention will be described with reference to FIGS.

First, in FIG. 1, the physical path (path of light) is changed from the optical switching element 12a → the working optical fiber core 14a → the optical switching element 12b by the optical switching elements 12a and 12b and the optical line switching controllers 13a and 13b. Optical switching element 12a → spare optical fiber core 14b
→ Switching to the light switching element 12b is performed. Here, the state of the optical switching element 12a or 12b will be described with reference to FIGS. 4 (a) and 4 (b).

In FIGS. 4 (a) and 4 (b), reference numeral 41 denotes a state detecting switch for detecting a switching state of the optical fiber core, reference numeral 42 denotes a fixed plug, and reference numeral 43 denotes a movable member with respect to the fixed plug 42. Movable plugs 44a and 44b for switching between the working optical fiber core 14a and the spare optical fiber core 14b are state detection terminals.

The physical path (light path) in FIG. 1 is the optical switching element 12a →
When the current optical fiber core 14a is formed into the optical switching element 12b, the movable plug 43 disposed opposite the fixed plug 42
Is in a state in which the detection switch 41 is turned off one step down as shown in FIG.

Further, when the physical path is formed from the optical switching element 12a → the spare optical fiber core 14b → the optical switching element 12b, the detection switch 41 is set in a state where the movable plug 43 is raised one step as shown in FIG. 4 (b). Is turned on. Therefore, it is possible to detect the state of the light switching element 12a or 12b by monitoring the resistance value of the state detection switch 41 that performs the ON / OFF operation depending on the state of the light switching element 12a or 12b.

FIG. 5 is a diagram illustrating the configuration of the optical line switching control device 13a or 13b.

The optical line switching control device 13a or 13b has a state detection terminal.
A current transmitting circuit 51 for transmitting a current between 44a and 44b, and a voltage detecting circuit 52 for detecting a voltage between the state detecting terminals 44a and 44b
And the magnitude of the voltage between the state detection terminals 44a and 44b,
A voltage determination circuit 53 that determines the switching state of the optical line by the optical switching element 12a or 12b, a display 24 that displays data, and a console 25 are mainly configured.

Note that, in this case, the output from the console 25 is supplied to the voltage determination circuit 53, which supplies the supplied command to the current transmission circuit 51 or is supplied from the voltage detection circuit 52. After a predetermined judgment is made on the various information, the information is displayed on the display 24.

With the optical path switching control device having the above configuration, the switching state between the working side optical fiber core and the protection side optical fiber after the switching is determined in the following flow.

First, immediately after the switching operation, a current is sent out between the state detection terminals 44a and 44b by the current sending circuit 51.

In the present embodiment, 25 mA is used as the current value, but this is merely for effective use of the power supply and miniaturization of the circuit scale, and is not limited to 25 mA.

Next, the voltage between the state detection terminals 44a and 44b is measured by the voltage detection circuit 52, and the voltage of the light switching element 12a is measured by the voltage determination circuit 53.
Or determine the state of 12b.

Since the current sending circuit 51 is composed of only a current control resistor connected to a 5 volt power supply, the power supply voltage is 5 volts when the state detection switch 41 is off and almost 0 when the state detection switch 41 is on.
A bolt appears between the state detection terminals 44a and 44b.

In addition, the TTL (transistor-transistor logic) positive logic parallel interface is used for the voltage detection circuit 52. Therefore, when the output of the voltage detection circuit 52 is 0.8 V or less, the state detection switch 41 is turned on, ie, the physical path is turned off. Is the optical switching element 12a → the active optical fiber core 14a → the optical switching element 12b, when the voltage is 2 V or more, the state detection switch 41 is off, that is, the physical path is the optical switching element 12a → the standby optical fiber core 14b → the optical switching element It is determined that it is formed on 12b.

 Note that a central control circuit was used for the voltage determination circuit 53.

Further, in the present embodiment, the voltage determination circuit 53 has a function and a circuit for making a transition to the immediately preceding state, so that a path disconnection due to a malfunction of the optical switching element 12a or 12b does not exceed 200 milliseconds. ing.

FIG. 6 is a view for explaining an embodiment according to claim 3, and basically has a structure in which the two embodiments are combined. In the figure, 61 is a voltage determination circuit. The voltage judgment circuit 61 is realized by a central control circuit.

In this embodiment, before switching, the current sending circuit shown in FIG.
21, the voltage detection circuit 22, and the voltage determination circuit 61 are used to determine the failure of the optical switching element 12a or 12b according to the procedure of the first embodiment, and after the switching, the current transmission circuit 51 in FIG.
Using the voltage detection circuit 52 and the voltage determination circuit 61, the second
By determining the operation failure of the optical switching element 12a or 12b according to the procedure of the embodiment, it is possible to determine the failure both before and after the switching.

[Effects of the Invention] As described above, according to the present invention, the following excellent effects can be obtained.

(A) An optical line switching control device according to claim 1, wherein a switching current is supplied between the switching terminals to perform an optical fiber switching operation, and between the switching terminals of the optical switching device. A switching circuit for transmitting a switching current to the optical fiber, a circuit for transmitting a failure determining current between the switching terminals of the optical switching element before switching the optical fiber core, and a failure determining circuit. A circuit for measuring the voltage between the switching terminals generated by the switching current and a circuit for determining whether the optical switching element is normal or defective based on the magnitude of the voltage. Before switching the optical fiber core, a failure judgment current different from the switching current is sent to the optical switching element, and the voltage between the switching terminals is measured to easily determine the failure of the optical switching element before switching. can do

(B) In the optical line switching control device according to the second aspect, the switching operation of the optical fiber is performed by supplying a switching current between the switching terminals, and the resistance value between the state detection terminals is changed according to the optical path state. An optical switching system comprising an optical line switching control device that sends a switching current between a changing optical switching element and a switching terminal of the optical switching element and a state detection current between the state detection terminals. A circuit for sending a switching current between the switching terminals of the optical switching element, and a switching current is supplied between the switching terminals of the optical switching element to perform an optical path switching operation, and then a state detection current is applied to the state of the optical switching element. A circuit for sending out between the detection terminals, a circuit for measuring a voltage between the state detection terminals generated by the state detection current, and a state of the optical switching element depending on the magnitude of the voltage, the state of the optical switching element on the working side optical path or the standby side. Circuit to determine the optical path After performing the switching operation of the optical fiber core, a state detection current is supplied between the state detection terminals of the optical switching element, and the state detection terminal is switched between the state detection terminals. , The switching state of the optical switching element immediately after the switching can be easily determined.

(C) In the optical line switching control device according to the third aspect, the switching operation of the optical fiber is performed by supplying a switching current between the switching terminals, and the resistance value between the state detection terminals according to the optical path state. In the optical switching system comprising an optical switching element and a switching current between the switching terminals of the optical switching element and an optical line switching control device that sends out a state detection current between the state detection terminals, A circuit for sending a switching current between the switching terminals of the optical switching element, a circuit for sending a failure determining current between the switching terminals of the optical switching element before switching the optical fiber, and a failure determining current. A circuit for measuring the generated voltage between the switching terminals, and a switching current is supplied between the switching terminals of the optical switching element to perform an optical path switching operation. The circuit to send between terminals A circuit for measuring the voltage between the state detection terminals generated by the detection current, and the voltage between the switching terminals of the switching element generated by the failure determination current and the voltage between the detection terminals generated by the state detection current It is characterized by comprising a circuit for determining the failure of the optical switching element and the state of the optical switching element according to the size and determining whether the state of the optical switching element is the working side optical path or the standby side optical path. Before and / or after the switching operation, the failure of the optical switching element can be determined, and communication interruption due to the failure of the optical switching element can be avoided or communication interruption can be detected in a short time, so that the reliability of switching can be reduced. There is an advantage that performance is improved.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS The drawings are shown for explaining one embodiment of the present invention, FIG. 1 is a block diagram for explaining the outline of an optical switching system, and FIG. FIG. 3 (a) is a diagram illustrating a short-circuit failure of the optical switching element, FIG. 3 (b) is a diagram illustrating a disconnection failure of the optical switching element, and FIG. 4 (a) is an optical switching element. FIG. 4 (b) is a diagram illustrating a standby state of the optical switching element, FIG. 5 (b) is a block diagram illustrating a configuration of the optical line switching control device according to claim 2, FIG. FIG. 6 is a block diagram illustrating the configuration of the optical line switching control device according to the third embodiment. 11a, 11b: transmission device, 12a, 12b: optical switching element, 13a, 13b: optical line switching control device, 14a: working optical fiber core, 14b ... standby optical fiber core, 14c ... Switching control optical fiber core, 21: Current sending circuit, 22: Voltage detection circuit, 23: Voltage judgment circuit, 24: Display, 25: Console, 26a, 26b: Switching terminal, 31 …… winding part of the actuator built into the optical switching element 41 ………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………… Circuit, 52: Voltage detection circuit, 53: Voltage judgment circuit, 63: Voltage judgment circuit.

Claims (3)

(57) [Claims] An optical switching element for switching an optical fiber by passing a switching current between switching terminals, and an optical line switch for transmitting a switching current between the switching terminals of the optical switching element. In the optical switching system including the control device, a circuit for sending a failure determination current between the switching terminals of the optical switching element before switching the optical fiber core, and a switching terminal generated by the failure determination current. An optical line switching control device, comprising: a circuit for measuring a voltage; and a circuit for determining whether the optical switching element is normal or defective based on the magnitude of the voltage. 2. An optical switching element in which an optical fiber is switched by applying a switching current between switching terminals, and a resistance value between the state detecting terminals changes according to an optical path state, and the optical switching element. An optical switching system comprising an optical line switching control device for transmitting a switching current between the switching terminals and a state detection current between the state detecting terminals, wherein the switching current is a switching terminal of the optical switching element. A circuit for transmitting a switching current between the switching terminals of the optical switching element and transmitting a state detection current between the state detecting terminals of the optical switching element after performing a switching operation of the optical path; The circuit includes a circuit for measuring a voltage between the state detection terminals generated by the state detection current, and a circuit for determining whether the state of the optical switching element is the working side optical path or the standby side optical path based on the magnitude of the voltage. Is characterized by Optical line switching control device. 3. An optical switching element in which an optical fiber is switched by applying a switching current between switching terminals, and a resistance value between the state detecting terminals changes according to an optical path state, and the optical switching element. An optical switching system comprising an optical line switching control device for transmitting a switching current between the switching terminals and a state detection current between the state detecting terminals, wherein the switching current is a switching terminal of the optical switching element. A circuit for sending a failure determination current between the switching terminals of the optical switching element before switching the optical fiber core, and a voltage between the switching terminals generated by the failure determination current are measured. Circuit and
A switching current is supplied between the switching terminals of the optical switching element to perform an optical path switching operation, and then a state detecting current is transmitted between the state detecting terminals of the optical switching element, and a state detecting current is generated by the circuit. A circuit for measuring the voltage between the state detection terminals, and the voltage between the switching terminals of the optical switching element generated by the failure determination current and the voltage between the state detection terminals generated by the state detection current An optical line switching control device, comprising: a circuit for determining a failure of an optical switching element and determining whether a state of the optical switching element is a working side optical path or a standby side optical path.