Optical line switching node equipment

Abstract

This disclosure provides an optical line switching node device N that is characterized by comprising: an optical switch unit 2 that performs optical path switching between communication optical fibers F-0 and F-1; communication optical signal extraction units 5-0 and 5-1 that extract some of communication optical signals from one or both of the communication optical fibers F-0 and F-1 and photoelectrically convert the extracted some of communication optical signals; and a communication optical signal power storage unit 6 that stores the energy of the some of communication optical signals photoelectrically converted by the communication optical signal extraction units 5-0 and 5-1 and drives the optical switch unit 2 by using the stored energy.

Description

[Technical field]

[0001] The present disclosure relates to techniques for performing optical path switching between input and output optical fibers for communications. [Background technology]

[0002] In optical fiber networks, particularly in access networks connecting telecommunications carrier equipment and optical terminals, optical path switching, which involves arbitrarily connecting and changing the routes of optical fiber core wires, is performed at a certain frequency in order to use facilities efficiently during installation and maintenance.

[0003] In a conventional technique, a telecommunications carrier's worker goes to the site and physically and manually switches optical paths. On the other hand, in Non-Patent Documents 1 and 2, a laser beam is transmitted from a telecommunications carrier's building or the like, and the laser beam is propagated through an optical fiber core line. The optical line switching node device photoelectrically converts the laser beam and stores the energy to perform remote optical path switching. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Tomohiro Kawano, Tatsuya Fujimoto, Kazuhide Nakae, Hiroshi Watanabe, and Kazunori Katayama, "Study on remote optical path switching nodes for future optical access networks," 2021 IEICE General Conference, B-13-16, 2021. [Non-Patent Document 2] Tatsuya Fujimoto, Tomohiro Kawano, Kazuhide Nakae, Hiroshi Watanabe, Kazunori Katayama, "Study on optical power supply efficiency for realizing remote optical path switching node," 2021 IEICE General Conference, B-13-17, 2021. Summary of the Invention [Problem to be solved by the invention]

[0005] However, in Non-Patent Documents 1 and 2, it is necessary to install a device for transmitting laser light in a building of a telecommunications carrier, which causes a problem of high installation and operation costs for the device for transmitting laser light. Furthermore, Non-Patent Documents 1 and 2 also cause a problem of a shortage of communication optical fiber core wires because the number of power supply optical fiber core wires increases when multiple optical line switching node devices are installed in an access field.

[0006] Therefore, in order to solve the above-mentioned problems, the present disclosure aims to perform remote optical path switching in an access field without installing a device for transmitting laser light in a telecommunications carrier's building, etc., and without increasing the number of optical fiber cores for power supply. [Means for solving the problem]

[0007] In order to solve the above problem, instead of photoelectrically converting laser light, a communication optical signal is photoelectrically converted, and then the stored energy is used to perform remote optical path switching.

[0008] Specifically, the present disclosure relates to an optical line switching node device comprising an optical switch unit that performs optical path switching between communication input / output optical fibers, a communication optical signal extraction unit that extracts a portion of a communication optical signal from one or both of the communication input / output optical fibers and performs photoelectric conversion of the extracted portion of the communication optical signal, and a communication optical signal storage unit that stores the portion of the communication optical signal photoelectrically converted in the communication optical signal extraction unit and drives the optical switch unit using the stored energy.

[0009] According to this configuration, since the optical signal for communication only needs to be photoelectrically converted, it is possible to perform remote optical path switching in the telecommunications carrier's building or the like without installing a device for transmitting laser light, and in the access field without increasing the number of optical fiber cores for power supply.

[0010] The present disclosure also provides an optical line switching node apparatus, further comprising an optical path switching monitoring unit that extracts a portion of the communication optical signal from the communication input / output optical fiber, photoelectrically converts the extracted portion of the communication optical signal, and monitors optical path switching between the communication input / output optical fibers using the photoelectrically converted portion of the communication optical signal, wherein the communication optical signal extraction unit extracts a portion of the communication optical signal from one or both of the communication input / output optical fibers in parallel with the optical path switching monitoring unit.

[0011] According to this configuration, the communication optical signal extracting unit is installed in parallel with the optical path switching monitoring unit, and the power storage mode and the monitoring mode can be executed in parallel.

[0012] The present disclosure also provides an optical line switching node apparatus, further comprising an optical path switching monitoring unit that extracts a portion of the communication optical signal from the communication input / output optical fiber, photoelectrically converts the extracted portion of the communication optical signal, and monitors optical path switching between the communication input / output optical fibers using the photoelectrically converted portion of the communication optical signal, wherein the communication optical signal extraction unit is integrated with the optical path switching monitoring unit and extracts a portion of the communication optical signal from one or both of the communication input / output optical fibers, and a storage mode of the portion of the communication optical signal by the communication optical signal storage unit and a monitoring mode of the optical path switching by the optical path switching monitoring unit are executed at parallel timing.

[0013] According to this configuration, the communication optical signal extracting unit is integrally installed with the optical path switching monitoring unit, and the power storage mode and the monitoring mode can be executed in parallel.

[0014] The present disclosure also provides an optical line switching node apparatus, further comprising an optical path switching monitoring unit that extracts a portion of the communication optical signal from the communication input / output optical fiber, photoelectrically converts the extracted portion of the communication optical signal, and monitors optical path switching between the communication input / output optical fibers using the photoelectrically converted portion of the communication optical signal, wherein the communication optical signal extraction unit is integrated with the optical path switching monitoring unit and extracts a portion of the communication optical signal from one or both of the communication input / output optical fibers, and a storage mode of the portion of the communication optical signal by the communication optical signal storage unit and a monitoring mode of the optical path switching by the optical path switching monitoring unit are executed at alternate timings.

[0015] According to this configuration, the communication optical signal extracting unit is integrally installed with the optical path switching monitoring unit, and the power storage mode and the monitoring mode can be executed at alternate timings.

[0016] The present disclosure also relates to an optical line switching node device, characterized in that the monitoring mode of optical path switching by the optical path switching monitoring unit is executed at a timing when the storage amount of a portion of the communication optical signal by the communication optical signal storage unit is secured.

[0017] According to this configuration, the monitoring mode can be executed using the stored energy, and if no energy is stored, the monitoring mode can be canceled.

[0018] The present disclosure also relates to an optical line switching node device, characterized in that one or both of the communication input / output optical fibers are multi-core optical fibers including a communication single-core optical fiber that transmits a communication optical signal, and a control single-core optical fiber that transmits a control optical signal of the optical switch unit.

[0019] According to this configuration, it is not necessary to separately prepare a communication single-core optical fiber and a control single-core optical fiber, and it is sufficient to prepare only one multi-core optical fiber. Effect of the Invention

[0020] In this way, the present disclosure makes it possible to perform remote optical path switching in an access field without installing a device for transmitting laser light in a telecommunications carrier's building, etc., and without increasing the number of optical fiber cores for power supply. [Brief description of the drawings]

[0021] [Figure 1] 1 is a diagram showing a schematic configuration of an optical line switching node apparatus according to the present disclosure; [Diagram 2] 1 is a diagram illustrating a configuration of an optical line switching node apparatus according to a first embodiment of the present disclosure. [Diagram 3] FIG. 11 is a diagram illustrating a configuration of an optical line switching node apparatus according to a second embodiment of the present disclosure. [Figure 4] FIG. 13 is a diagram illustrating a configuration of an optical line switching node apparatus according to a third embodiment of the present disclosure. [Diagram 5] FIG. 13 is a diagram illustrating a procedure of an optical path switching monitoring process according to a third embodiment of the present disclosure. [Figure 6] FIG. 13 is a diagram illustrating a configuration of an optical line switching node apparatus according to a fourth embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present disclosure will be described with reference to the accompanying drawings. The embodiments described below are examples of the present disclosure, and the present disclosure is not limited to the following embodiments.

[0023] (Schematic configuration of optical line switching node device according to the present disclosure) A schematic configuration of an optical line switching node device according to the present disclosure is shown in Fig. 1. The optical line switching node device N is connected to a communication carrier device P via a communication optical fiber F-0 (such as an optical fiber of the 0th system of a working system), is connected to a plurality of optical terminals T via a communication optical fiber F-1 (such as an optical fiber of the 1st system of a backup system), and is connected to a monitoring and controlling device C via a control optical fiber FC.

[0024] The optical line switching node equipment N includes integrated connectors 1-0, 1-1, an optical switch unit 2, an optical switch control unit 3, an optical switch control line 4, communication optical signal extraction units 5-0, 5-1, communication optical signal storage unit 6, prisms 7-0, 7-1, optical sensors 8-0, 8-1, an optical path switching monitoring unit 9, a node equipment control unit 10, a coupler 11, an optical detector 12, a MEMS switch 13, and a circulator 14 (*-0 corresponds to system 0 of the working system, and *-1 corresponds to system 1 of the standby system).

[0025] The integrated connectors 1-0 and 1-1 integrate the communication optical fibers F-0 and F-1. The optical switch unit 2 (such as an N×N optical switch) switches the optical path between the communication optical fibers F-0 and F-1. The optical switch control unit 3 controls the optical switch unit 2 according to commands from the node device control unit 10. The optical switch control power supply line 4 controls and supplies power to the optical switch unit 2.

[0026] The communication optical signal extracting units 5-0 and 5-1 extract a part of the communication optical signals from the communication optical fibers F-0 and F-1 and perform photoelectric conversion on the extracted part of the communication optical signals. The communication optical signal storage unit 6 stores the part of the communication optical signals photoelectrically converted in the communication optical signal extracting units 5-0 and 5-1 and drives each processing unit such as the optical switch unit 2 using the stored energy.

[0027] Here, only the communication optical signal extracting unit 5-0 may extract a portion of the communication optical signal only from the communication optical fiber F-0. On the other hand, only the communication optical signal extracting unit 5-1 may extract a portion of the communication optical signal only from the communication optical fiber F-1. Details of the communication optical signal extracting units 5-0 and 5-1 will be described later in the first to third embodiments.

[0028] The prisms 7-0 and 7-1 extract a part of the communication optical signals from the communication optical fibers F-0 and F-1. The optical sensors 8-0 and 8-1 photoelectrically convert the extracted part of the communication optical signals. The optical path switching monitoring unit 9 monitors the optical path switching between the communication optical fibers F-0 and F-1 using the part of the communication optical signals photoelectrically converted according to an instruction from the node device control unit 10. The node device control unit 10, the coupler 11, the photodetector 12, the MEMS switch 13, and the circulator 14 will be described later in the third embodiment.

[0029] In this way, since the optical signal for communication only needs to be photoelectrically converted, remote optical path switching can be performed in the telecommunications carrier device P without installing a device for transmitting laser light, and without increasing the number of optical fiber cores for power supply in the access field.

[0030] (Configuration of the optical line switching node device according to the first embodiment of the present disclosure) The configuration of an optical line switching node device according to the first embodiment of the present disclosure is shown in Fig. 2. Communication optical signal extracting units 5-0 and 5-1 extract a portion of communication optical signals from communication optical fibers F-0 and F-1 in "parallel" with prisms 7-0 and 7-1 associated with an optical path switching monitoring unit 9.

[0031] Specifically, the communication optical signal extraction units 5-0 and 5-1 include prisms 51-0 and 51-1 and photoelectric conversion elements 52-0 and 52-1. The prisms 51-0 and 51-1 extract a portion of the communication optical signals from the communication optical fibers F-0 and F-1 using Fresnel reflection or the like. The photoelectric conversion elements 52-0 and 52-1 are optical sensors or the like, and perform photoelectric conversion of the extracted portion of the communication optical signals. The communication optical signal storage unit 6 is a storage capacitor or the like, and stores the portion of the communication optical signals that have been photoelectrically converted, and drives each processing unit such as the optical switch unit 2.

[0032] For example, the incident optical power per core of the communication optical fiber F-0 is 10 mW, and the number of cores of the communication optical fiber F-0 accommodated in the integrated connector 1-0 is 20 cores. If the optical loss of the integrated connector 1-0 is 0.5 dB (90% transmission), the incident optical power after passing through the integrated connector 1-0 is 10 mW x 20 cores x 90% = 180 mW. If the optical reflection of the prism 51-0 is 10%, the incident optical power after reflection of the prism 51-0 is 180 mW x 10% = 18 mW. If the conversion efficiency of the photoelectric conversion element 52-0 is 30%, the storage power after conversion of the photoelectric conversion element 52-0 is 18 mW x 30% = 5.4 mW.

[0033] Here, the communication optical fibers F-0 and F-1 constantly propagate the communication optical signals. Therefore, the communication optical signal storage unit 6 can obtain sufficient power to drive each processing unit such as the optical switch unit 2 even if only a part of the communication optical signals is photoelectrically converted.

[0034] In this way, the communication optical signal extractor 5 is installed in "parallel" with the optical path switching monitor 9, and the power storage mode and the monitor mode can be executed in "parallel" timing.

[0035] (Configuration of an optical line switching node apparatus according to a second embodiment of the present disclosure) The configuration of an optical line switching node apparatus according to the second embodiment of the present disclosure is shown in Fig. 3. The communication optical signal extracting units 5-0 and 5-1 are "integrated" with the prisms 7-0 and 7-1 associated with the optical path switching monitoring unit 9 to extract some communication optical signals from the communication optical fibers F-0 and F-1. Here, the storage mode of some communication optical signals by the communication optical signal storage unit 6 and the monitoring mode of optical path switching by the optical path switching monitoring unit 9 are executed at "parallel" timing.

[0036] Specifically, the communication optical signal extraction units 5-0 and 5-1 include half mirrors 53-0 and 53-1 and photoelectric conversion elements 54-0 and 54-1. The prisms 7-0 and 7-1 extract a part of the communication optical signals from the communication optical fibers F-0 and F-1 using Fresnel reflection or the like. The half mirrors 53-0 and 53-1 transmit and reflect the extracted part of the communication optical signals. The photoelectric conversion elements 54-0 and 54-1 are optical sensors or the like, and perform photoelectric conversion on the part of the reflected communication optical signals. The communication optical signal storage unit 6 is a storage capacitor or the like, and stores the part of the communication optical signals that have been photoelectrically converted, and drives each processing unit such as the optical switch unit 2.

[0037] For example, the incident optical power per core of the communication optical fiber F-0 is 10 mW, and the number of cores accommodated in the communication optical fiber F-0 in the integrated connector 1-0 is 20 cores. If the optical loss of the integrated connector 1-0 is 0.5 dB (90% transmission), the incident optical power after passing through the integrated connector 1-0 is 10 mW x 20 cores x 90% = 180 mW. If the optical reflection of the prism 7-0 is 10%, the incident optical power after reflection by the prism 7-0 is 180 mW x 10% = 18 mW. If the optical reflection and optical transmission of the half mirror 53-0 are 70% and 30%, respectively, the incident optical power after reflection by the half mirror 53-0 is 18 mW x 70% = 12.6 mW. If the conversion efficiency of the photoelectric conversion element 54-0 is 30%, the power for storage after conversion of the photoelectric conversion element 54-0 is 12.6 mW×30%=3.8 mW.

[0038] Here, the communication optical fibers F-0 and F-1 constantly propagate the communication optical signals. Therefore, the communication optical signal storage unit 6 can obtain sufficient power to drive each processing unit such as the optical switch unit 2 even if only a part of the communication optical signals is photoelectrically converted.

[0039] In this way, the communication optical signal extractor 5 is installed "integrally" with the optical path switching monitor 9, and the power storage mode and the monitor mode can be executed "in parallel."

[0040] (Configuration of an optical line switching node apparatus according to a third embodiment of the present disclosure) The configuration of an optical line switching node apparatus according to a third embodiment of the present disclosure is shown in Fig. 4. The communication optical signal extracting units 5-0 and 5-1 are "integrated" with the prisms 7-0 and 7-1 associated with the optical path switching monitoring unit 9 to extract some communication optical signals from the communication optical fibers F-0 and F-1. Here, the storage mode of some communication optical signals by the communication optical signal storage unit 6 and the monitoring mode of optical path switching by the optical path switching monitoring unit 9 are executed at "alternate" timing.

[0041] Specifically, the communication optical signal extraction units 5-0 and 5-1 include optical sensors 8-0 and 8-1 and switches 55-0 and 55-1. The prisms 7-0 and 7-1 extract a portion of the communication optical signals from the communication optical fibers F-0 and F-1 using Fresnel reflection or the like. The optical sensors 8-0 and 8-1 photoelectrically convert the extracted portion of the communication optical signals. The switches 55-0 and 55-1 are electrically driven switches or the like, and switch between the storage mode and the monitoring mode at an "alternate" timing. The communication optical signal storage unit 6 is a storage capacitor or the like, and stores the portion of the communication optical signals that have been photoelectrically converted, and drives each processing unit such as the optical switch unit 2.

[0042] For example, the incident optical power per core of the communication optical fiber F-0 is 10 mW, and the number of cores accommodated in the communication optical fiber F-0 of the integrated connector 1-0 is 20 cores. If the optical loss of the integrated connector 1-0 is 0.5 dB (90% transmission), the incident optical power after passing through the integrated connector 1-0 is 10 mW x 20 cores x 90% = 180 mW. If the optical reflection of the prism 7-0 is 10%, the incident optical power after reflection by the prism 7-0 is 180 mW x 10% = 18 mW. If the conversion efficiency of the optical sensor 8-0 is 30%, the storage power after conversion by the optical sensor 8-0 is 18 mW x 30% = 5.4 mW. Taking into consideration practical operation, if the time ratio of the switch 55-0 in the power storage mode and the monitoring mode is 95%:5%, the power storage when the switch 55-0 is switched is 5.4 mW×95%=5.1 mW.

[0043] Here, the communication optical fibers F-0 and F-1 constantly propagate the communication optical signals. Therefore, the communication optical signal storage unit 6 can obtain sufficient power to drive each processing unit such as the optical switch unit 2 even if only a part of the communication optical signals is photoelectrically converted.

[0044] In this way, the communication optical signal extracting unit 5 is installed "integrally" with the optical path switching monitoring unit 9, and the power storage mode and the monitoring mode can be executed at "alternate" timing.

[0045] A procedure of the optical path switching monitoring process of the third embodiment of the present disclosure is shown in Fig. 5. The optical path switching monitoring mode by the optical path switching monitoring unit 9 is executed at a timing when the storage amount of a part of the communication optical signal is secured by the communication optical signal storage unit 6. Specifically, the following process is executed.

[0046] The node device control unit 10 receives an inquiry about port information from the monitoring control device C via the coupler 11 and the photodetector 12 (step S1). The port information is port information for optical path switching between the communication optical fibers F-0 and F-1. The node device control unit 10 checks whether the communication optical signal storage unit 6 has enough stored power (step S2).

[0047] If the amount of power stored in the communication optical signal storage unit 6 is not sufficient for the port information inquiry (step S3, NO), the node device control unit 10 notifies the monitoring control device 11 of the insufficient amount of power storage via the MEMS switch 13, the circulator 14, and the coupler 11 (step S4). If the amount of power stored in the communication optical signal storage unit 6 is sufficient for the port information inquiry (step S3, YES), the node device control unit 10 notifies the monitoring control device 11 of the port information via the MEMS switch 13, the circulator 14, and the coupler 11 (step S10). Specifically, the following processes of steps S5 to S9 are executed.

[0048] The node device control unit 10 commands the switches 55-0 and 55-1 to switch from the communication optical signal storage mode to the optical path switching monitoring mode (step S5). The node device control unit 10 queries the optical path switching monitoring unit 9 for port information (step S6). The optical path switching monitoring unit 9 acquires the port information from the optical sensors 8-0 and 8-1 (step S7). The optical path switching monitoring unit 9 notifies the node device control unit 10 of the port information (step S8). The node device control unit 10 commands the switches 55-0 and 55-1 to switch from the optical path switching monitoring mode to the communication optical signal storage mode (step S9).

[0049] In this way, the monitoring mode can be carried out using stored energy, and the monitoring mode can be discontinued if no energy is stored.

[0050] (Configuration of an optical line switching node apparatus according to a fourth embodiment of the present disclosure) The configuration of an optical line switching node apparatus according to a fourth embodiment of the present disclosure is shown in Fig. 6. The communication optical fibers F-0 and F-1 are multi-core optical fibers M-0 and M-1 including a communication single-core optical fiber for transmitting a communication optical signal and a control single-core optical fiber for transmitting a control optical signal of the optical switch unit 2. Here, the fourth embodiment is applicable to the first to third embodiments since the configuration of the communication optical signal extraction units 5-0 and 5-1 does not matter. Furthermore, only the communication optical fiber F-0 may be the multi-core optical fiber M-0. On the other hand, only the communication optical fiber F-1 may be the multi-core optical fiber M-1.

[0051] When terminating the multi-core optical fibers M-0, M-1 in the optical line switching node equipment N, the multi-core optical fibers M-0, M-1 are inserted into the fan-out connectors 15-0, 15-1. Inside the optical line switching node equipment N, the multi-core optical fibers M-0, M-1 are converted into single-core optical fibers. A communication single-core optical fiber is connected to the optical switch unit 2, and a control single-core optical fiber is connected to the coupler 11.

[0052] In this way, it is not necessary to separately prepare a communication single-core optical fiber and a control single-core optical fiber, but it is sufficient to prepare only one multi-core optical fiber. [Industrial Applicability]

[0053] The optical line switching node equipment disclosed herein can perform remote optical path switching in an access field without installing a device for transmitting laser light in a telecommunications carrier's building, etc., and without increasing the number of optical fiber cores for power supply. [Explanation of symbols]

[0054] N: Optical line switching node equipment P: Telecommunications carrier equipment C: Monitoring and control device T: Optical terminal F-0, F-1: Optical fiber for communication FC: Control optical fiber M-0, M-1: Multi-core optical fiber 1-0, 1-1: Integrated connector 2: Optical switch section 3: Optical switch control unit 4: Optical switch controlled power supply line 5-0, 5-1: Optical signal extraction unit for communication 6: Optical signal storage unit for communication 7-0, 7-1: Prism 8-0, 8-1: Optical sensor 9: Optical path switching monitoring unit 10: Node device control unit 11: Coupler 12: Photodetector 13: MEMS switch 14: Circulator 15-0, 15-1: Fan-out connectors 51-0, 51-1: Prism 52-0, 52-1: Photoelectric conversion element 53-0, 53-1: Half mirror 54-0, 54-1: Photoelectric conversion element 55-0, 55-1: Switch

Claims

1. an optical switch unit for switching optical paths between input and output optical fibers for communication; a communication optical signal extraction unit that extracts a portion of the communication optical signal from one or both of the communication input / output optical fibers and performs photoelectric conversion of the extracted portion of the communication optical signal; a communication optical signal storage unit that stores a part of the communication optical signal photoelectrically converted in the communication optical signal extraction unit and drives the optical switch unit using the stored energy; an optical path switching monitoring unit that extracts a part of the communication optical signal from the communication input / output optical fiber, photoelectrically converts the extracted part of the communication optical signal, and monitors optical path switching between the communication input / output optical fibers using the photoelectrically converted part of the communication optical signal, the communication optical signal extraction unit is integrated with the optical path switching monitoring unit and extracts a part of the communication optical signal from one or both of the communication input / output optical fibers; a storage mode of a part of the communication optical signals by the communication optical signal storage unit and a monitoring mode of the optical path switching by the optical path switching monitoring unit are executed at alternate timings; The optical path switching monitoring mode by the optical path switching monitoring unit is executed at a timing when the storage amount of a part of the communication optical signal by the communication optical signal storage unit is secured.

2. An optical line switching node device comprising:

2. One or both of the communication input / output optical fibers is a multi-core optical fiber including a communication single-core optical fiber for transmitting a communication optical signal and a control single-core optical fiber for transmitting a control optical signal of the optical switch unit.

2. The optical line switching node device according to claim 1.

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