Optical fiber path switching device and method

Abstract

To provide an optical fiber path switching apparatus which implements optical path switching by supplying weak optical power, and a method to be executed by the apparatus.SOLUTION: An optical fiber path switching apparatus includes: an optical path changeover switch 1 for selecting an active optical fiber 102 or an emergency optical fiber 103; a WDM coupler 3 configured to divide wavelength of power-feed optical signals issued from a feeding power source device 2; a photoelectric transducer 4 which converts the power-feed optical signals wavelength-divided by the WDM coupler 3 to electricity; a power storage device 5 which accumulates electricity output from the photoelectric transducer 4; a voltage booster 6 which boosts a voltage output from the power storage device 5 to a necessary voltage for actuating the optical path changeover switch 1; and a control apparatus 8 which performs monitoring a voltage output from the photoelectric transducer 4, monitoring a voltage of the power storage device 5, controlling the voltage booster 6, and controlling a power source and path switching of the optical path changeover switch 1.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a technology for supplying power by optical power feeding and switching optical fiber paths in an environment where a power source cannot be easily secured. [Background technology]

[0002] As an optical fiber path switching technology, a device has been proposed for use in places where commercial power is available, such as in communication buildings and user facilities. This device monitors the communication optical power of two optical fiber paths, one for working use and one for emergency use, and switches the optical fiber path to the system that is not causing any problems when an abnormality occurs, such as a drop in optical power. (For example, see Non-Patent Document 1.)

[0003] As a technology for switching optical fiber paths without using commercial power, a device that converts optical energy from optical fibers into electric power and switches optical fiber paths has been proposed (see, for example, Non-Patent Document 2). However, in Non-Patent Document 2, the optical power that needs to be supplied is very large, about 1 W, and there is a problem that it is difficult to put into practical use from a safety standpoint. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] DENSO Corporation: Automatic optical transmission line switching device, https: / / www.kk-denso.co.jp / products / automatic-light.php, (Accessed 2020.12.16) [Non-Patent Document 2] R. Helkey ​​et al., “Remotely Powered Optical Switch for Remote Subscriber Aggregation and OTDR Measurement in PON,” 33rd European Conference and Exhibition of Optical Communication, Berlin, Germany, 2007, pp. 1-2, doi: 10.1049 / ic:20070283. Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present disclosure is to realize optical path switching by supplying weak optical power. [Means for solving the problem]

[0006] In the present disclosure, a configuration is realized in which weak optical power is stored over time, and a large amount of power can be extracted when operating an optical path changeover switch. The controller monitors the stored power status, and after confirming whether there is sufficient power, the optical path changeover switch is operated, thereby realizing optical path changeover by supplying weak optical power.

[0007] Specifically, the optical fiber route switching device of the present disclosure comprises: An optical fiber route switching device is used in an optical transmission path in which a station side transmission device and a subscriber side transmission device, which are opposed to each other, transmit and receive signal light via an optical fiber, and switches the route of the optical fiber to a working optical fiber or an emergency optical fiber, an optical path changeover switch for switching between the working optical fiber and the emergency optical fiber; a WDM coupler that splits the wavelength of a power supply optical signal emitted from a power supply device; an opto-electrical converter for converting the power supply optical signal demultiplexed by the WDM coupler into an electric signal; a power storage device that stores the electricity output from the photoelectric converter; a voltage boosting device that boosts an output voltage from the power storage device to a voltage required to operate the optical path changeover switch; a control device that monitors an output voltage from the photoelectric converter, monitors a voltage of the power storage device, controls the voltage boost device, and controls a power supply and path switching of the optical path changeover switch; Equipped with.

[0008] Specifically, the optical fiber route switching method of the present disclosure includes: A method for switching a path of a station-side transmission device and a subscriber-side transmission device, which are used in an optical transmission line for transmitting and receiving signal light via an optical fiber, and which is executed by an optical fiber path switching device for switching a path of the optical fiber to a working optical fiber or an emergency optical fiber, comprising: The WDM coupler splits the power supply optical signal emitted from the power supply light source device, an optical / electrical converter converts the power supply optical signal demultiplexed by the WDM coupler into an electrical signal; a power storage device that stores the electricity output from the photoelectric converter; a voltage boosting device that boosts an output voltage from the power storage device to a voltage required to operate the optical path changeover switch; An optical path changeover switch switches between the working optical fiber and the emergency optical fiber using the power stored in the power storage device. Effect of the Invention

[0009] The present disclosure can realize optical path switching by supplying weak optical power. [Brief description of the drawings]

[0010] [Figure 1] 1 shows an example of the configuration of an optical fiber route switching system. [Diagram 2] 2 shows an example of the configuration of a power supply light source device. [Diagram 3] 2 shows an internal configuration of a power storage device in an optical fiber route switching device. [Figure 4] 1 shows an optical fiber path switching method using an optical fiber path switching device. [Diagram 5] 1 shows an example of the configuration of an optical fiber route switching system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the drawings. Note that the present disclosure is not limited to the embodiments shown below. These implementation examples are merely illustrative, and the present disclosure can be implemented in various forms with various modifications and improvements based on the knowledge of those skilled in the art. Note that components with the same reference numerals in this specification and drawings are assumed to indicate the same components.

[0012] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 shows an embodiment of the present disclosure. The optical fiber path switching system of the present disclosure includes a power supply light source device 2 that emits a power supply optical signal, and an optical fiber path switching device. The optical fiber path switching device is used in an optical transmission path in which a central office transmission device 100 and a subscriber side transmission device 101 that are opposed to each other transmit and receive signal light via an optical fiber, and is disposed in an environment where power cannot be easily secured, such as an underground manhole or an overhead closure. The power supply light source device 2 is disposed in a communication building in which the central office transmission device 100 is disposed. The optical fiber path switching device is supplied with power by optical power supply from the power supply light source device 2, and switches the path to a working optical fiber 102 or an emergency optical fiber 103 as the optical fiber.

[0013] More specifically, the optical fiber route switching device of the present disclosure comprises: a WDM (Wavelength Division Multiplexing) coupler 3 for multiplexing / demultiplexing the wavelengths of the power supply optical signals emitted from the power supply device 2; an optical path changeover switch 1 for switching between a working optical fiber 102 and an emergency optical fiber 103; a photoelectric converter 4 for converting the optical energy of the power supply optical signal emitted from the power supply light source device 2 into electrical energy; a storage device 5 that stores the electric energy converted by the photoelectric converter 4; a voltage boosting device 6 that boosts the output voltage from the power storage device 5 to a voltage required to operate the optical path changeover switch 1; an optical path changeover switch power switch 7 for controlling the power supply to the optical path changeover switch 1; a control device 8 that monitors the output voltage from the photoelectric converter 4, monitors the voltage of the power storage device 5, controls the voltage boost device 6, and controls the power supply and path switching of the optical path changeover switch 1; Equipped with.

[0014] The power supply optical signal emitted from the power supply light source device 2 is multiplexed onto a working optical fiber 102 in an optical branching coupler 104 installed in a communication building. The power supply optical signal multiplexed onto the working optical fiber 102 is demultiplexed by a WDM coupler 3 and supplied to an opto-electrical converter 4.

[0015] The power supply optical signal is converted into electricity in the photoelectric converter 4 and supplied to the power storage device 5. The power storage device 5 stores the electricity supplied from the photoelectric converter 4. The power stored in the power storage device 5 is supplied to the control device 8 and the voltage boost device 6.

[0016] The control device 8 monitors the voltage converted by the photoelectric converter 4 using a photoelectric converter output voltage monitoring signal line 9. The control device 8 also monitors the voltage of the electricity stored in the power storage device 5 through a power storage device voltage monitoring signal line 10. This makes it possible to determine whether or not the power required for the optical path switching operation in the optical path switching switch 1 is stored.

[0017] The voltage boost device 6 boosts the voltage of the power stored in the power storage device 5 to a voltage level required for the operation of the optical path switching switch 1. The electricity boosted by the voltage boost device 6 is supplied or stopped to the optical path switching switch 1 by the optical path switching power switch 7. In this way, the present disclosure can supply the power required for the optical path switching switch 1 to the optical path switching switch 1.

[0018] The start and stop of the voltage booster 6 is controlled by the control device 8 via a voltage booster control signal line 13. The optical path switch power switch 7 is turned on and off by the control device 8 via an optical path switch power control signal line 12. The control device 8 supplies the optical path switch 1 with power required for the optical path switching operation, and then performs the optical path switching operation from the control device 8 via an optical path switch control signal line 11.

[0019] In the present disclosure, power is supplied from the power storage device 5 to the voltage boost device 6, the optical path switch power switch 7, and the optical path switch 1 in that order. Therefore, in the present disclosure, the voltage boost device 6 is started, the optical path switch power switch 7 is turned ON, and the optical path switch 1 switches the optical path in that order.

[0020] In these configurations, only the control device 8 and the power storage device 5 operate in a normal state. The control device 8 charges the power storage device 5 while checking whether the power stored in the power storage device 5 is sufficient to operate the optical path changeover switch 1. By operating the entire system with the minimum necessary power, it is possible to ensure enough power to operate the optical path changeover switch 1 even with the minute power of about 0.5 mW obtained by optical power feeding.

[0021] Therefore, even with a weak optical energy of the power supply optical signal of about 0.5 mW, the optical path changeover switch 1 can perform optical fiber path changeover from the working optical fiber 102 to the emergency optical fiber 103 and vice versa.

[0022] 2 shows an example of remotely controlling the optical path switch 1 using a power supply light source device 2. An intensity modulator 21 modulates the intensity of light emitted from the LD light source 20 with a control signal for remotely controlling the optical path switch 1. This makes it possible to transmit a control signal for remotely controlling the optical path switch 1 using a power supply optical signal output from the power supply light source device 2.

[0023] The modulation of the optical output in the intensity modulator 21 is realized by controlling the intensity modulator 21 through an optical fiber path switching instruction signal line 23 by an optical fiber path switching instruction device 24 such as a computer. The optical power supply signal modulated by the intensity modulator 21 is converted into electricity in the photoelectric converter 4. By monitoring the output voltage from the photoelectric converter 4 at this time with the control device 8, it becomes possible to receive the control signal output from the optical fiber path switching instruction device 24.

[0024] 3 shows an embodiment of the power storage device 5. The power storage device 5 includes a control device capacitor 52 for supplying power to the control device 8, and an optical path switching capacitor 54 for supplying power to the optical path switching switch 1. Power from the photoelectric converter 4 is supplied to two systems, the control device capacitor 52 and the optical path switching capacitor 54. A control device capacitor backflow prevention diode 51 is connected between the photoelectric converter 4 and the control device capacitor 52, and an optical path switching capacitor backflow prevention diode 53 is connected between the photoelectric converter 4 and the optical path switching capacitor 54.

[0025] The power stored in these two systems of capacitors 52 for the control device and capacitors 54 for the optical path changeover switch does not flow back and forth between the two systems of capacitors due to backflow prevention diodes 51 for the capacitor for the control device and backflow prevention diodes 53 for the capacitor for the optical path changeover switch. As a result, even if a large amount of power is temporarily consumed from capacitor 54 for the optical path changeover switch to operate the optical path changeover switch 1, this does not affect capacitor 52 for the control device, and it becomes possible to continue stable operation of the control device 8.

[0026] The power from the photoelectric converter 4 is first charged in the control device capacitor 52. The charging voltage of the control device capacitor 52 is monitored by the optical path switch capacitor charge controller 56 via the control device capacitor voltage monitoring signal line 57. When the charging voltage of the control device capacitor 52 reaches or exceeds a set voltage, the optical path switch capacitor charge controller 56 controls the optical path switch capacitor charge control switch 55 to start charging the optical path switch capacitor 54 from the optical path switch capacitor charge control switch 55.

[0027] With these configurations, the power from the photoelectric converter 4 is first charged in the control device capacitor 52. The power charged in the control device capacitor 52 is immediately supplied to the control device 8, and the control device 8 is started first. Then, together with the start-up of the control device 8, it is possible to start monitoring the output voltage of the photoelectric converter 4 and the voltage of the power storage device 5. Therefore, the optical fiber path switching device of the present disclosure is capable of switching the optical fiber path from the working optical fiber 102 to the emergency optical fiber 103, or from the emergency optical fiber 103 to the working optical fiber 102, only when it receives an optical fiber path switching instruction from the optical fiber path switching instruction device 24 and determines that the power required to operate the optical path switching switch 1 is sufficient.

[0028] FIG. 4 illustrates an example of an optical fiber path switching method using an optical fiber path switching device according to an embodiment of the present disclosure. In the photoelectric converter output voltage monitoring step S70, the time and number of times that the output voltage from the photoelectric converter 4 has dropped, for example, from 2V or more (HIGH) to 0.5V or less (LOW) are monitored. By corresponding a digital 1 when the output voltage is LOW and a digital 0 when the output voltage is HIGH, it is possible to receive a switching command to the optical path changeover switch 1 that combines 1 and 0. Also, if the output voltage remains LOW for a certain period of time or longer, it is possible to determine that the working optical fiber 102 has been broken. In this way, in the photoelectric converter output voltage monitoring step S70, it is determined whether the received switching command is for "emergency" or "working", and whether the working optical fiber 102 is "broken" or "normal".

[0029] If the determination result is "emergency use" or "current use", the voltage of the power storage device 5 is measured in a power storage device voltage monitoring step S71. If the voltage is equal to or lower than a specified value, the voltage of the power storage device 5 is measured again in a power storage device voltage monitoring step S71 after a certain period of time. If the voltage is higher than the specified value, boosting by the voltage boost device 6 is started in a voltage boost device control step S72.

[0030] Next, in optical path switch power control step S73, power supply to the optical path switch 1 is started, and then in optical path switch control step 74, the optical path switch 1 is operated to switch the optical path to "emergency" or "working" according to the received switching command. After the optical path is switched, power supply to the optical path switch 1 is stopped in optical path switch power control step S73, and voltage boosting by the voltage boosting device 6 is stopped in voltage boosting device control step S72.

[0031] On the other hand, when it is determined in the photoelectric converter output voltage monitoring step S70 that the working optical fiber 102 is broken, the optical path changeover switch 1 immediately switches to the emergency optical fiber 103.

[0032] First, in a voltage boosting device control step S72, boosting of the voltage boosting device 6 is started, in an optical path switching power supply control step S73, power is supplied to the optical path switching device 1, and in an optical path switching control step S74, the optical path switching device 1 is switched to the emergency optical fiber 103.

[0033] Thereafter, the output voltage of the photoelectric converter 4 is monitored in a photoelectric converter output voltage monitoring step S70. If it is determined that the output voltage becomes HIGH and the working optical fiber 102 has returned to "normal", the process returns to the storage device voltage monitoring step S71 of the flow determined to be "working" in the photoelectric converter output monitoring step S70, and at the point in time when the storage voltage becomes greater than a specified value, the optical path changeover switch 1 is switched to the working optical fiber 102.

[0034] Furthermore, when the power of the storage device 5 becomes 0 due to a "disconnection" state and the working optical fiber 102 returns to "normal", power storage from 0 is required to resume the photoelectric converter output voltage monitoring process 70. Therefore, by providing a WDM coupler 111 and an optical coupler 110 in the emergency optical fiber 103 as shown in FIG. 5, the power supply optical signal propagated through the emergency optical fiber 103 can be demultiplexed by the WDM coupler 111. This makes it possible to store some power in the storage device 5 by supplying a small amount of power even when the working optical fiber 102 is in a "disconnection" state, and enables the photoelectric converter output voltage monitoring process 70 to be immediately resumed when the working optical fiber 102 returns to "normal".

[0035] Furthermore, by making the branching ratio of the optical branching coupler 104 unequal, for example 6:4, a difference occurs in the light receiving power of the photoelectric converter 4 when the working optical fiber 102 is broken and when the emergency optical fiber 103 is broken. In other words, since a difference occurs in the output voltage of the photoelectric converter 4, it becomes possible to distinguish between a break in the working optical fiber 102 and a break in the emergency optical fiber 103 by setting a reference value in advance.

[0036] In this embodiment, the case where there is one optical path switch 1 has been described, but the present disclosure is not limited to this. It goes without saying that even if there are multiple optical path switches 1, it is possible to achieve this by sequentially switching them one by one while monitoring whether the necessary power is secured.

[0037] (Effects of the present disclosure) As described above, according to the present disclosure, it is possible to switch optical fiber paths by a safe level of extremely weak optical power supply even in communication optical fibers. Therefore, even in places where it was not easy to secure a power source in the past, such as in underground manholes or in closures installed above ground, it is possible to supply power by optical power supply using existing communication optical fibers and switch optical fiber paths. [Industrial Applicability]

[0038] The present disclosure can be applied to the information and communications industry. [Explanation of symbols]

[0039] 1: Optical path changeover switch 2: Light source for power supply 3: WDM coupler 4: Photoelectric converter 5: Energy storage device 6: Voltage booster 7: Optical path changeover switch Power switch 8: Control device 9: Photoelectric converter output voltage monitoring signal line 10: Storage battery voltage monitoring signal line 11: Optical path changeover switch control signal line 12: Optical path changeover switch power control signal line 13: Voltage booster control signal line 20:LD light source 21: Intensity modulator 23: Optical fiber route switching instruction signal line 24: Optical fiber route switching instruction device 51: Reverse current prevention diode for control device capacitor 52: Capacitor for control device 53: Reverse current prevention diode for capacitor of optical path changeover switch 54: Capacitor for optical path switching switch 55: Capacitor charge control switch for optical path switching switch 56: Capacitor charge controller for optical path switching switch 57: Capacitor voltage monitoring signal line for control device 58: Capacitor charge control switch signal line for optical path switching switch 70: Photoelectric converter output voltage monitoring step 71: Storage device voltage monitoring step 72: Voltage boost device control step 73: Optical path switching power control step 74: Optical path switching control step 100: Station side transmission equipment 101: Subscriber side transmission device 102: Current optical fiber 103: Emergency optical fiber 110: Optical coupler 111: WDM coupler

Claims

1. An optical fiber route switching device is used in an optical transmission path in which a station side transmission device and a subscriber side transmission device, which are opposed to each other, transmit and receive signal light via an optical fiber, and switches the route of the optical fiber to a working optical fiber or an emergency optical fiber, an optical path changeover switch for switching between the working optical fiber and the emergency optical fiber; a WDM coupler for demultiplexing a wavelength of a power supply optical signal generated from a power supply device and multiplexed onto the working optical fiber; an opto-electrical converter for converting the power supply optical signal demultiplexed by the WDM coupler into an electric signal; a power storage device that stores the electricity output from the photoelectric converter; a voltage boosting device that boosts an output voltage from the power storage device to a voltage required to operate the optical path changeover switch; a control device that monitors an output voltage from the photoelectric converter, monitors a voltage of the power storage device, controls the voltage boost device, and controls a power supply and path switching of the optical path changeover switch; An optical fiber route switching device comprising:

2. The power storage device is a control device capacitor for storing power for operating the control device; a capacitor for storing power for operating the optical path changeover switch; a capacitor charge control switch for controlling the start and end of charging the capacitor for the optical path switching switch; a capacitor charge controller for the optical path switching switch that monitors a voltage of the capacitor for the control device and controls the capacitor charge control switch for the optical path switching switch so as to start charging the capacitor for the optical path switching switch when the voltage of the capacitor for the control device becomes equal to or higher than a set voltage; 2. The optical fiber route switching device according to claim 1, comprising:

3. The power storage device is a control device capacitor backflow prevention diode connected between the photoelectric converter and the control device capacitor for preventing backflow from the control device capacitor; a capacitor backflow prevention diode for an optical path switching switch, connected between the photoelectric converter and the capacitor for the optical path switching switch, for preventing backflow from the capacitor for the optical path switching switch; 3. The optical fiber route switching device according to claim 2, comprising:

4. the power supply optical signal is intensity modulated by a control signal for remotely operating the optical path changeover switch, the control device acquires the control signal from the electrical signal output from the photoelectric converter, and switches the optical path changeover switch in accordance with the acquired control signal.

4. The optical fiber route switching device according to claim 1, wherein:

5. A method for switching a path of a station-side transmission device and a subscriber-side transmission device, which are used in an optical transmission line for transmitting and receiving signal light via an optical fiber, and which is executed by an optical fiber path switching device for switching a path of the optical fiber to a working optical fiber or an emergency optical fiber, comprising: a WDM coupler that demultiplexes the power supply optical signal emitted from the power supply light source device and multiplexed in the working optical fiber; an optical / electrical converter converts the power supply optical signal demultiplexed by the WDM coupler into an electrical signal; a power storage device that stores the electricity output from the photoelectric converter; a voltage boosting device that boosts an output voltage from the power storage device to a voltage required to operate the optical path changeover switch; the optical path changeover switch switches between the working optical fiber and the emergency optical fiber using the power stored in the power storage device; The optical fiber route switching device includes: When a control signal for the optical path changeover switch is received using the power supply optical signal, After activating the optical path changeover switch, switching between the working optical fiber and the emergency optical fiber in accordance with the control signal. The method characterized by:

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