JP2008167242A - Optical cross connect apparatus and method for controlling optical cross connect - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve reliability against failures in an optical cross correct apparatus corresponding to an active system and a stand-by system. <P>SOLUTION: An optical cross connect apparatus is provided with 2n×2n optical switch modules, n optical branching units for respectively dividing input optical signals 1 to n into two branches and connecting the branches to an active system input ports 1 to n and stand-by system input ports n+1 to 2n, and n output light switching units for respectively selecting either one of output optical signals from the active system output ports 1 to n and the stand-by system output ports n+1 to 2n and outputting the selected optical signals as output optical signals 1 to n. The optical switch modules are configured so as to set the stand-by system paths of the input port i+n and the output port j+n, the input port i and the output port j+n, and the input port i+n and the output port j in active system paths between the input port i and the output port j in the active system. The output light switching units respectively switch the output optical signal j according to the switching of the output port j and the output port j+n. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical cross-connect device and an optical cross-connect control method that switch a plurality of optical signal paths.

  In general, in an optical network system, an optical cross-connect device is used to switch a plurality of optical signal paths. An optical cross-connect device uniquely connects an arbitrary input line and output line in a switch unit arranged between a plurality of optical signal input units and an optical signal output unit, and changes the connection combination as required. (Patent document 1).

  FIG. 9 shows a configuration example of the optical cross-connect device. In the figure, an optical switch module 10 that does not convert signal light into an electrical signal but switches it as it is from the viewpoint of simplicity of configuration, cost, and reliability is used for the switch section of the optical cross-connect device. The optical switch module 10 has n (n is an integer greater than or equal to 2) input ports for inputting input signal lights 1 to n and n output ports for outputting output signal lights 1 to n. The optical switch module 10 is configured to connect each input port and each output port under the control of a switch control circuit (not shown).

  FIG. 10 shows a configuration example of an optical cross-connect device used in a wavelength division multiplexing optical transmission system. In the figure, m input wavelength-multiplexed optical signals S1 to Sm (m is an integer of 2 or more) have wavelengths λ1 to λn (n is an integer of 2 or more) by wavelength demultiplexers 12-1 to 12-m, respectively. The optical signal is demultiplexed and input to each input port of the optical switch module 10. The optical switch module 10 cross-connects n × m optical signals under the control of a switch control circuit (not shown), and outputs the optical signals to m sets of output ports for each of the wavelengths λ1 to λn. The m sets of optical signals for each of the wavelengths λ1 to λn output from the output port of the optical switch module 10 are multiplexed by the corresponding wavelength multiplexers 13-1 to 13-m, respectively, and output wavelength multiplexed optical signals S1 to S1. Each is output as Sm.

  Here, when wavelength multiplexing is performed by the wavelength multiplexer 13, the wavelengths of the optical signals need to be different from each other, but in general, the wavelength used for the wavelength multiplexed optical signal of each optical fiber transmission line is as follows. In many cases, λ1 to λn are the same. Therefore, optical signals having the same wavelength may be cross-connected to the n output ports of the optical switch module 10 corresponding to each wavelength multiplexer 13. In such a case, as shown in FIG. 11, a wavelength converter 14 is provided for some or all of the n output ports of the optical switch module 10 corresponding to each wavelength multiplexer 13, and wavelength competition occurs. In such a case, there is a configuration in which either wavelength is converted and then input to the wavelength multiplexer 13 for wavelength multiplexing. There is also a configuration in which the wavelength converter 14 is inserted on the input port side.

Here, in the optical cross-connect device shown in FIG. 9, in preparation for a failure of the optical switch module 10, a standby optical switch module 11 is used as shown in FIG. The same applies to the optical cross-connect device shown in FIG. The input optical signals 1 to n are branched by the optical branching devices 21-1 to 21-n and input to the input ports of the working optical switch module 10 and the standby optical switch module 11. Input optical signals are cross-connected by the optical switch modules 10 and 11, and output optical signals 1 to n output from the output ports are selected and output by the output optical switching units 22-1 to 22-n, respectively. . The switch control circuit can continue to cross-connect n optical signals by switching to the standby optical switch module 11 when a failure occurs in the active optical switch module 10.
Japanese Patent Laid-Open No. 06-292246

  In the redundant configuration shown in FIG. 12, for example, the input port 1 and the output port 2 of the active optical switch module 10 are connected, and the input port 1 and the output port 2 of the standby optical switch module 11 are similarly connected. Switching from the active system to the standby system is possible by selecting the output light switching units 22-1 to 22-n. That is, when a failure occurs in the input port 1 of the working optical switch module 10, the input optical signal 1 is transmitted from the input port 1 to the output port 2 and the output optical switch 22-2 of the standby optical switch module 11. Can be output as the output optical signal 2. However, if a failure occurs in the output port 2 of the standby optical switch module 11 in this state, the input optical signal 1 is interrupted.

  Similarly, when the output port 2 of the active optical switch module 10 and the input port (n + 1) of the standby optical switch module 11 fail simultaneously, the input optical signal 1 is disconnected.

  In addition, when the conventional n × n optical cross-connect device including the active system and the standby system shown in FIG. 12 is expanded to 2n × 2n, for example, the n × n optical switch modules 10 and 11 are replaced with 2n × 2n. Although it will be replaced with a type, instantaneous interruption of the working optical signal at the time of replacement is inevitable.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an optical cross-connect device and an optical cross-connect control method capable of improving reliability against failures in an optical cross-connect device corresponding to an active system and a standby system.

  It is another object of the present invention to provide an optical cross-connect control method capable of facilitating expansion without instantaneous interruption of an active optical signal in an optical cross-connect device having an active system and a standby system. And

  The first invention includes an optical switch module that has input ports 1 to 2n (n is an integer of 2 or more) and output ports 1 to 2n and performs cross-connection of optical signals between 2n × 2n input / output ports; Each of the input optical signals 1 to n is branched into two, each one of the input optical signals 1 to n is connected to the input ports 1 to n of the optical switch module, and each of the other input optical signals 1 to n is input to the optical switch module Each of n optical branching devices connected to ports (n + 1) to 2n, output optical signals of output ports 1 to n of the optical switch module, and output optical signals of output ports (n + 1) to 2n of the optical switch module And n output optical switches that output as output optical signals 1 to n, and the optical switch module uses the input ports 1 to n and the output ports 1 to n as the active system, and the input port (n + 1) ~ 2 And the output ports (n + 1) to 2n are used as backup systems, and the active system path between the active system input port i (i is an integer from 1 to n) and the output port j (j is an integer from 1 to n). In addition to the backup path of the input port (i + n) and the output port (j + n), the backup path of the input port i and the output port (j + n) and the backup path of the input port (i + n) and the output port j The output optical switch is configured to switch the output optical signal j in accordance with switching between the output port j and the output port (j + n) in the optical switch module.

  The second invention is an optical switch module having an input port of 1 to 2 nm (n and m are integers of 2 or more) and an output port of 1 to 2 nm and performing cross-connection of optical signals between 2 nm × 2 nm input / output ports And m optical branching devices each branching the input wavelength-multiplexed optical signals S1 to Sm in two, and each of the input wavelength-multiplexed optical signals S1 to Sm branched by the m optical branching devices into m sets of wavelengths λ1 .About..lamda.n optical signals, and the first m wavelength demultiplexers connected to the input ports 1 to nm of the optical switch module for each set, and the other branched by the m optical branching units. Are divided into m sets of optical signals of wavelengths λ1 to λn, and the second m wavelengths connected to the input port (nm + 1) to 2 nm of the optical switch module for each set. Demultiplexer and optical switch module output port 1-nm M sets of output optical signals of wavelengths λ1 to λn output from the first m wavelength multiplexers, and m sets of output ports (nm + 1) to 2 nm of the optical switch module. Second m wavelength multiplexers that respectively combine the output optical signals of wavelengths λ1 to λn, wavelength multiplexed optical signals output from the first m wavelength multiplexers, and the first m Wavelength-multiplexed optical signals output from the wavelength multiplexers of m, respectively, m optical couplers for outputting as output wavelength-multiplexed optical signals S1 to Sm, m optical splitters and second m optical splitters An optical signal of a predetermined wavelength is passed between the wavelength demultiplexer or between the second m wavelength multiplexers and the m optical couplers, and optical signals of other wavelengths are blocked. With optical wavelength selective blocker, the optical switch module uses input ports 1-nm and output ports 1-nm The input port (nm + 1) to 2 nm and the output port (nm + 1) to 2 nm are used as a backup system, and the current input port i (i is an integer from 1 to nm) and the output port j (j is an integer from 1 to nm) In addition to the backup path of the input port (i + nm) and the output port (j + nm), the backup path and the input port (i + nm) of the input port i and the output port (j + nm) ) And the output path j, the optical path selection blocker selects the backup path output to the output port (nm + 1) to 2 nm of the backup system of the optical switch module. Occasionally, an optical signal having a wavelength corresponding to the output port is allowed to pass, an optical signal having another wavelength is blocked, and a spare signal output to the standby output port (nm + 1) to 2 nm of the optical switch module. When the system path is not selected, all wavelengths of optical signals are blocked.

  In the optical cross-connect device according to the second aspect of the invention, in place of the optical wavelength selective blocker, a wavelength of a wavelength that is not output in the standby path output to the standby output port (nm + 1) to 2 nm of the optical switch module. The optical signal may be connected to an output port different from the wavelength-compatible output port so that the wavelength multiplexer functions as an optical wavelength selective blocker.

  Further, in the optical cross-connect device of the second invention, each output port of the optical switch module is provided with a wavelength converter, and instead of the wavelength selective blocker, the wavelength converter includes a standby output port of the optical switch module ( Of the backup paths output in the range of (nm + 1) to 2 nm, it may be configured to include a function of blocking optical signals having wavelengths that are not output.

  In the optical cross-connect device according to the first aspect of the invention, the input / output ports of the optical switch module are divided into two areas, that is, the active system and the standby system, and the input ports and output ports of the active system and the standby system are divided in each area The arrangement may be such that the predetermined intervals that are not adjacent to each other are secured with regularity.

  In the optical cross-connect device of the second invention, the input / output port of the optical switch module is divided into 2 m areas for each wavelength multiplexed optical signal, and the input ports corresponding to the respective wavelengths in the 2 m areas and The output ports may be arranged with regularity so as to ensure at least a predetermined interval that is not adjacent between the same wavelengths.

  According to a third aspect of the present invention, in the optical cross-connect control method for switching between the active system and the standby system in the optical cross-connect device of the first invention, the optical switch module uses the input ports 1 to n and the output ports 1 to n as active. System, input ports (n + 1) to 2n and output ports (n + 1) to 2n are used as standby systems, and the current input port i (i is an integer from 1 to n) and output port j (j is an integer from 1 to n) ) In addition to the backup path of the input port (i + n) and the output port (j + n), the backup path and the input port of the input port i and the output port (j + n) ( i + n) and the standby path of the output port j are set, and the output optical switch switches the output optical signal j according to the switching of the output port j and the output port (j + n) in the optical switch module.

  According to a fourth aspect of the present invention, in the optical cross-connect control method for switching between the active system and the standby system in the optical cross-connect device of the second invention, the optical switch module uses the input ports 1 to nm and the output ports 1 to nm. The input port (nm + 1) to 2 nm and the output port (nm + 1) to 2 nm are standby systems, and the active input port i (i is an integer from 1 to nm) and the output port j (j is an integer from 1 to nm) ) In addition to the backup path of the input port (i + nm) and the output port (j + nm), the backup path and the input port of the input port i and the output port (j + nm) i + nm) and the output path j are set as standby paths, and the optical wavelength selective blocker is used for the standby path output to the standby output ports (nm + 1) to 2 nm of the optical switch module. Is selected, the optical signal of the wavelength corresponding to the output port is allowed to pass, the optical signal of the other wavelength is blocked, and the standby system is output to the standby system output port (nm + 1) to 2 nm of the optical switch module. When a path is not selected, all wavelength optical signals are blocked.

  In the optical cross-connect control method according to the fourth aspect of the present invention, an optical signal having a wavelength that is not output among the standby paths output to the standby system output port (nm + 1) to 2 nm of the optical switch module is wavelength-corresponding. The wavelength multiplexer may be connected to an output port different from the output port and function as an optical wavelength selective blocker.

  A fifth invention is an optical cross-connect control method for adding an optical cross-connect device corresponding to an active system and a standby system of the first or second invention, wherein the optical switch module is the first optical switch module, and the same Using the second optical switch module having the configuration, the optical signal and the optical signal connected to the standby input port and the output port of the first optical switch module are converted into the active input port of the second optical switch module. Then, the connection is switched to the output port, and the optical signal to be added is connected to the input port and the output port of the standby system of the first optical switch module.

  The first and third inventions use a 2n × 2n optical switch module for an optical cross-connect device that uses two n × n optical switch modules to constitute an active system and a standby system. By separately using the input port and output port, and the standby input port and output port, it is possible to form three backup paths for one active path. Thereby, the reliability with respect to a failure can be improved.

  In the second and fourth inventions, an active system and a standby system are configured by using two nm × nm optical switch modules, and a light of 2 nm × 2 nm is provided for an optical cross-connect device corresponding to a wavelength multiplexed optical signal. By using a switch module and dividing it into an active input port and an output port and a standby input port and an output port, three standby paths can be formed for one active path. . Thereby, the reliability with respect to a failure can be improved.

  According to a fifth aspect of the present invention, in the optical cross-connect device having the active system and the standby system according to the first or second invention, the input and output ports of the standby system are used as expansion ports, thereby Expansion can be facilitated without instantaneous interruption.

(First embodiment)
FIG. 1 shows a first embodiment of the optical cross-connect device of the present invention.
In the figure, input optical signals 1 to n are branched by optical branching devices 21-1 to 21-n, and the active system input ports 1 to n of the 2n × 2n optical switch module 30 and the standby system input ports (n + 1). ) To 2n. The 2n × 2n optical switch module 30 cross-connects 2n optical signals under the control of a switch control circuit (not shown) and outputs them to each output port. The output optical signals output from the working output ports 1 to n and the standby output ports (n + 1) to 2n of the optical switch module 30 are respectively output optical switchers 22-1 to 22-n. Each is selected and output. Note that the output light switching units 22-1 to 22-n may be configured to block the optical signals from the standby output ports (n + 1) to 2n at all times and to conduct when switching from the active system to the standby system. .

  The present embodiment is characterized in that an n × n optical cross-connect device having an active system and a standby system is replaced with one 2n instead of the optical switch modules 10 and 11 constituting the conventional active system and the standby system shown in FIG. The optical switch module 30 of × 2n is used. The active system input ports 1 to n and the standby system input ports (n + 1) to 2n, the active system output ports 1 to n and the standby system output ports (n + 1) to 2n of the optical switch module 30 are used for the active system light. Although it corresponds to each input / output port of the switch module 10 and the standby optical switch module 11, the 2n × 2n optical switch module 30 can set the path between the working / standby cross-crossing. As a result, the following cross connection becomes possible.

  In FIG. 12, an example will be described in which the input port 1 and output port 2 of the active optical switch module 10 are connected, and the input port 1 and output port 2 of the standby optical switch module 11 are similarly connected. At this time, when a failure occurs in the input port 1 of the active optical switch module 10, the input optical signal 1 is sent from the input port 1 to the output port 2 and the output optical switch 22-2 of the standby optical switch module 11. And output as an output optical signal 2. At this time, if a failure occurs in the output port 2 of the standby optical switch module 11, the input optical signal 1 is disconnected.

  On the other hand, in the configuration of the present embodiment shown in FIG. 1, the working path of the input port 1 and the output port 2 of the optical switch module 30 is detoured to the backup path of the input port (n + 1) and the output port (n + 2). This corresponds to a case where a failure occurs in the output port (n + 2). In this case, the failure of the output port (n + 2) is avoided by connecting the input port (n + 1) and the output port 2 and switching the output optical switch 22-2 to select the output port 2 side. Can do.

  The input optical signal 1 is also disconnected when the output port 2 of the working optical switch module 10 shown in FIG. 12 and the input port (n + 1) of the standby optical switch module 11 fail simultaneously. On the other hand, in the configuration of this embodiment shown in FIG. 1, this corresponds to the simultaneous failure of the output port 2 and the input port (n + 1) of the optical switch module 30, but even in this case, the input port 1 and the output port (n + 2) are connected. By switching so that the output port (n + 2) side is selected by the output light switch 22-2, the disconnection of the input optical signal 1 can be avoided.

  As described above, the configuration of the conventional active system and the standby system shown in FIG. 12 is a completely redundant configuration, and a configuration in which a failure is avoided by switching the path of one optical switch module to the path of the other optical switch module. Therefore, it is impossible to deal with a double failure that spans both systems as in the above two examples. On the other hand, in the configuration of the present embodiment, a detour path is possible by the dotted line path shown in FIG. 1, and the reliability can be improved.

(Second Embodiment)
FIG. 2 shows a second embodiment of the optical cross-connect device of the present invention.
The feature of this embodiment is that when the conventional nm × nm optical switch module 10 corresponding to the wavelength multiplexed optical signal shown in FIG. 10 is made compatible with the active system and the standby system, two nm × nm as shown in FIG. The optical switch modules 10 and 11 are not used, but a single 2 nm × 2 nm optical switch module 31 is used. The functions and effects are the same as those of the first embodiment of FIG. 1 for the n × n optical cross-connect device having the active system and the standby system of FIG.

  In the figure, one of the input wavelength multiplexed optical signals S1 to Sm branched by the optical couplers 21-1 to 21-m is converted into m sets of wavelengths λ1 to λn by the active wavelength demultiplexers 12-1 to 12-m. And is input to the current input port 1-nm of the 2 nm × 2 nm optical switch module 31 for each set. The other input wavelength multiplexed optical signals S1 to Sm branched by the optical couplers 21-1 to 21-m are m sets of wavelengths λ1 to λ1 by the standby wavelength demultiplexers 12- (m + 1) to 12-2m. The optical signal is demultiplexed into optical signals of λn, and input to the standby system input port (nm + 1) to 2 nm of the optical switch module 31 of 2 nm × 2 nm for each set.

  The 2 nm × 2 nm optical switch module 31 cross-connects 2 nm optical signals under the control of a switch control circuit (not shown) and outputs them to each output port. M sets of optical signals of wavelengths λ1 to λn output from the active system output ports 1 to nm of the 2 nm × 2 nm optical switch module 31 are multiplexed by the wavelength multiplexers 13-1 to 13-m, respectively. The output wavelength multiplexed optical signals S1 to Sm are output through the optical couplers 26-1 to 26-m, respectively. Further, m sets of optical signals of wavelengths λ1 to λn output from the standby output port (nm +) to 2 nm of the optical switch module 31 of 2 nm × 2 nm are respectively wavelength multiplexers 13- (m + 1) to 13−. The signals are combined at 2 m and output as output wavelength multiplexed optical signals S1 to Sm through optical wavelength selective blockers 23-1 to 23-m and optical couplers 26-1 to 26-m, respectively.

  It is to be noted that the active wavelength multiplexers 13-1 to 13-m and the standby wavelength multiplexers 13- (m + 1) to 13-2m are light cross-connected by the optical switch module 31 of 2 nm × 2 nm. Each signal is input. Usually, when the working path is normal, the optical wavelength selective blockers 23-1 to 23-m block the optical signals of all wavelengths, and the standby output port (nm +) to 2 nm of the optical switch module 31. This prevents the optical signals output from from joining.

  Here, for example, when a failure occurs in the optical signal of the wavelength λn of the input wavelength multiplexed optical signal Sm cross-connected from the active input port nm of the optical switch module 31 of 2 nm × 2 nm to the output port n, the output The optical signal of wavelength λn is missing from the wavelength multiplexed optical signal S1. At this time, the standby system of the optical signal having the wavelength λn of the input wavelength multiplexed optical signal Sm is cross-connected from the input port 2 nm to the output port nm + n, and the optical signal having the wavelength λn is received by the corresponding optical wavelength selective blocker 23-1. The optical signal of wavelength λn of the input wavelength-multiplexed optical signal Sm is restored, and interference between the same wavelengths of the active system and the standby system is avoided. Can do. Such an optical wavelength selective blocker is provided on the input side of the 2 nm × 2 nm optical switch module 31 with optical couplers 21-1 to 21-m and standby wavelength demultiplexers 12- (m + 1) to 12-2m. You may insert between each.

  Similarly to the first embodiment, for example, in the optical signal having the wavelength λn of the input wavelength multiplexed optical signal Sm, the above-described cross-connect failure from the active input port nm to the active output port n is performed as described above. In addition to the path from the standby input port 2 nm to the standby output port (nm + n), the path from the active input port nm to the standby output port (nm + n), the standby input port 2 nm to the active system The failure recovery is possible by the path to the output port n.

(Third embodiment)
FIG. 3 shows a third embodiment of the optical cross-connect device of the present invention.
This embodiment shows another form that realizes the same function as the second embodiment shown in FIG. Instead of the optical wavelength selective blockers 23-1 to 23-m in the second embodiment of FIG. 2, the connection ports of the standby wavelength multiplexers 13- (m + 1) to 13-2m are shifted substantially. Thus, it functions as an optical wavelength selective blocker.

  In the configuration of FIG. 2, the standby output ports (nm + 1) to (nm + n) of the 2 nm × 2 nm optical switch module 31 are connected to the ports of wavelengths λ1 to λn of the wavelength multiplexer 13- (m + 1). The wavelength corresponding to each output port of the system is cross-connected. The same applies to other output ports and other wavelength multiplexers.

  On the other hand, in the configuration of FIG. 3, the standby output ports (nm + 1) to (nm + n) of the optical switch module 31 of 2 nm × 2 nm are connected to the ports of wavelengths λ1 to λn of the wavelength multiplexer 13- (m + 1). However, for example, optical signals obtained by circulating one wavelength λ1 to λn are cross-connected to the standby output ports (nm + 1) to (nm + n). Accordingly, the wavelength multiplexer 13- (m + 1) does not output the wavelength multiplexed optical signal, and the output wavelength multiplexed optical signal output from the active wavelength multiplexer 13-1 from the output optical multiplexer 23-1. S1 is output.

  Here, for example, when a failure occurs in the optical signal of the wavelength λn of the input wavelength multiplexed optical signal Sm cross-connected from the active input port nm of the optical switch module 31 of 2 nm × 2 nm to the output port n, the output The optical signal of wavelength λn is missing from the wavelength multiplexed optical signal S1. At this time, the standby system of the optical signal having the wavelength λn of the input wavelength multiplexed optical signal Sm switches the cross-connect from the input port 2 nm to the output port nm + 1 to the original output port nm + n corresponding to the wavelength λn. As a result, the optical signal having the wavelength λn of the input wavelength multiplexed optical signal Sm is output as the output wavelength multiplexed optical signal S1 via the wavelength multiplexer 13- (m + 1) and the optical coupler 26-1. Note that the wavelength λ (n−1) that has been cross-connected to the output port nm + n is alternately blocked and cross-connected to the output port nm + 1, thereby being blocked by the wavelength multiplexer 13- (m + 1).

  Similarly to the second embodiment, for example, in the optical signal having the wavelength λn of the input wavelength multiplexed optical signal Sm, the above-described cross-connect failure from the active input port nm to the active output port n is performed as described above. In addition to the path from the standby input port 2 nm to the standby output port (nm + n), the path from the active input port nm to the standby output port (nm + n), the standby input port 2 nm to the active system The failure recovery is possible by the path to the output port n.

  In the second embodiment, only the wavelength that is cross-connected by the optical switch module 31 of 2 nm × 2 nm and further detoured by the wavelength selective blocker 23 from the wavelength multiplexed optical signal output to the standby output port and combined. However, a function for turning on / off the output may be added to the output port of the standby system. This function is normally controlled (when there is no abnormality) so that no output is generated for all ports, and only for optical signals (wavelengths) in which an abnormality has occurred in the active system, optical signals of the corresponding wavelength Is controlled to generate

  Further, this function can be dealt with by installing an optical switch or an optical variable attenuator at each output port of the standby system of the 2 nm × 2 nm optical switch module 31. In addition, if the wavelength converter is provided in each output port of the 2 nm × 2 nm optical switch module 31, the wavelength converter may have the same function. In addition, when using a 3D MEMS optical switch that can switch the connection between input and output ports by controlling the angle of the micromirror, which will be described later, the blocking or passing function for each wavelength is realized without additional components. it can.

(Fourth embodiment)
In the configuration of the first embodiment shown in FIG. 1, in the 2n × 2n optical switch module 30, the active and standby input optical signals 1 to n are simultaneously cross-connected. In the configurations of the second to third embodiments shown in FIGS. 2 to 3, in the optical switch module 31 of 2 nm × 2 nm, the light of each wavelength of the input wavelength multiplexed optical signals S1 to Sm of the active system and the standby system is used. Signals are cross-connected at the same time. In this case, in addition to the active system and the standby system, optical signals having the same wavelength corresponding to the number m of input / output paths of the wavelength multiplexed optical signal are cross-connected.

  By the way, when an optical space switch having a three-dimensional configuration is used as the optical switch modules 30 and 31, crosstalk increases between adjacent ports. Therefore, crosstalk can be reduced by assigning optical signals of the same wavelength in the active system and the standby system, or optical signals of the same wavelength in the wavelength multiplexing system to ports that are not close by the optical space switch. The following description will be divided into three types of optical space switches constituting the optical switch module. Here, the optical switch module 30 corresponding only to the active system and the standby system will be described as an example, but the same applies to the wavelength multiplexing optical switch module 31.

  FIG. 4 shows a first configuration example of the optical switch module 30. In FIG. 4, the optical switch module 30 has a configuration in which an input optical fiber array 3a in which a plurality (2n) of optical fibers are two-dimensionally arranged and an output optical fiber array 3b are opposed to each other. The angle of each optical fiber of the input optical fiber array 3a and the angle of each optical fiber of the output optical fiber array 3b are changed by a mechanical variable mechanism so that the optical coupling loss is reduced between the optical fibers to be connected. The light beam is spatially propagated by adjusting to.

  In this configuration, the input optical fiber array 3a is divided into two parts, that is, the active system and the standby system, and the positions of the n input ports of the active system and the positions of the n input ports of the standby system correspond to each other. The input optical signals of the system are arranged so as not to be adjacent to each other. Similarly, the output optical fiber array 3b is divided into two parts, the active system and the standby system, and the positions of the n output ports of the active system and the positions of the n output ports of the standby system are made to correspond to each other. The output optical signals are arranged so as not to be adjacent to each other.

  FIG. 5 shows a second configuration example of the optical switch module 30. In FIG. 5, an optical switch module 30 includes a collimator array 1a, 1b in which a plurality (2n) collimators are two-dimensionally arranged, and a MEMS (Micro Electric Mechanical System) in which a plurality (2n) mirrors are two-dimensionally arranged. The mirror array 2 is combined. An input optical fiber array in which a plurality (2n) of optical fibers are two-dimensionally arranged corresponding to each collimator is connected to the collimator array 1a forming the input port group. Connected to the collimator array 1b forming the output port group is an output optical fiber array in which a plurality (2n) of optical fibers are two-dimensionally arranged corresponding to each collimator.

  The angle of each mirror of the MEMS mirror array 2 is controlled by the MEMS technique, and connection (switching of an optical path) between arbitrary input / output ports is possible depending on the reflection angle of each mirror. In this configuration, the input optical fiber array corresponding to the collimator array 1a is divided into two parts, the active system and the standby system, and the positions of the n input ports of the active system and the positions of the n input ports of the standby system are made to correspond to each other. The active and standby input optical signals are arranged so as not to be adjacent to each other. Similarly, the output optical fiber array corresponding to the collimator array 1b is divided into two parts, the active system and the standby system, and the positions of the n output ports of the active system and the positions of the n output ports of the standby system are respectively associated with each other. The output optical signals of the active system and the standby system are arranged so as not to be adjacent.

  FIG. 6 shows a third configuration example of the optical switch module 30. In FIG. 6, an optical switch module 30 includes collimator arrays 1a and 1b in which a plurality (2n) collimators are two-dimensionally arranged and MEMS mirror arrays 2a and 2b in which a plurality (2n) mirrors are two-dimensionally arranged. It is a combined configuration. An input optical fiber array in which a plurality (2n) of optical fibers are two-dimensionally arranged corresponding to each collimator is connected to the collimator array 1a forming the input port group. Connected to the collimator array 1b forming the output port group is an output optical fiber array in which a plurality (2n) of optical fibers are two-dimensionally arranged corresponding to each collimator.

  The angles of the mirrors of the MEMS mirror arrays 2a and 2b are controlled by the MEMS technique, and any input / output port can be connected (switching of optical paths) by a combination of mirrors to be reflected. In this configuration, the input optical fiber array corresponding to the collimator array 1a is divided into two parts, the active system and the standby system, and the positions of the n input ports of the active system and the positions of the n input ports of the standby system are made to correspond to each other. The active and standby input optical signals are arranged so as not to be adjacent to each other. Similarly, the output optical fiber array corresponding to the collimator array 1b is divided into two parts, the active system and the standby system, and the positions of the n output ports of the active system and the positions of the n output ports of the standby system are respectively associated with each other. The output optical signals of the active system and the standby system are arranged so as not to be adjacent.

(Fifth embodiment)
7 and 8 show a fifth embodiment of the optical cross-connect device of the present invention. The present embodiment will be described by taking the 2n × 2n optical switch module 30 shown in FIG. 1 as an example, but is similarly applicable to the 2 nm × 2 nm optical switch module 31 shown in FIGS.

  In FIG. 7, the 2n × 2n optical switch module 30a, the optical branching units 21-1 to 21-n, and the output optical switching units 22-1 to 22-n are the same as those in the first embodiment, and the input optical signal Switching between the active system and the standby system between 1 to n and the output optical signals 1 to n is realized by one 2n × 2n optical switch module 30a.

  In the present embodiment, the scale is increased to a 2n × 2n optical cross-connect device compared to the n × n optical cross-connect device that has been configured as an active system and a standby system using a 2n × 2n optical switch module 30a. Applies to The input optical signals 1 to n are connected to the input ports 1 to n and the input ports (n + 1) to 2n of the 2n × 2n optical switch module 30a via the optical branching devices 21-1 to 21-n. The output optical signals 1 to n are switched between the output optical signals from the output ports 1 to n and the output ports (n + 1) to 2n of the 2n × 2n optical switch module 30a by the output optical switches 22-1 to 22-n. It is taken out. The optical branching devices 21-1 to 21-n and the input ports (n + 1) to 2n of the 2n × 2n optical switch module 30a are connected via optical connectors 24-1 to 24-n. Similarly, the output optical switches 22-1 to 22-n and the output ports (n + 1) to 2n of the 2n × 2n optical switch module 30a are connected via optical connectors 25-1 to 25-n. .

  Here, a case where the input optical signal (n + 1) and the output optical signal (n + 1) are added will be described. A 2n × 2n optical switch module 30b having the same configuration as the 2n × 2n optical switch module 30a is added. Assume that the optical connectors 24-1 and 25-1 associated with each other are optical connectors 24-1a and 24-1b and optical connectors 25-1a and 25-1b, respectively.

  The input optical signal (n + 1) is connected to the optical connector 24- (n + 1) a and the input port (n + 1) of the 2n × 2n optical switch module 30b via the optical splitter 21- (n + 1). Optical connectors 24- (n + 1) b to 24-2nb are connected to the input ports 1 to n of the 2n × 2n optical switch module 30b. Next, the optical connectors 24-1a and 24-1b are disconnected, the optical connector 24- (n + 1) a and the optical connector 24-1b are connected, and the optical connector 24-1a and the optical connector 24- (n + 1) b are connected. . Also in the optical connectors 24-2 to 24-n, the connection is switched between the optical connectors 24-2a to 24-na and the optical connectors 24- (n + 2) b to 24-2nb.

  The output optical signal (n + 1) is connected to the optical connector 25- (n + 1) a and the output port (n + 1) of the 2n × 2n optical switch module 30b via the output optical switch 22- (n + 1). Optical connectors 25- (n + 1) b to 25-2nb are connected to the output ports 1 to n of the 2n × 2n optical switch module 30b. Next, the optical connectors 25-1a and 25-1b are disconnected, the optical connector 25- (n + 1) a and the optical connector 25-1b are connected, and the optical connector 25-1a and the optical connector 25- (n + 1) b are connected. . Also in the optical connectors 25-2 to 25-n, the connection is switched between the optical connectors 25-2a to 25-na and the optical connectors 25- (n + 2) b to 25-2nb.

  By switching the connection of the optical connectors as described above, as shown in FIG. 8, the standby system of the input optical signal 1 is connected to the 2n × 2n optical switch module 30b via the optical connectors 24-1a and 24- (n + 1) b. Input to input port 1. Similarly, the standby system of the input optical signals 2 to n is input to the input ports 2 to n of the 2n × 2n optical switch module 30b. The input system of the input optical signal (n + 1) to be added is the input of the 2n × 2n optical switch module 30 via the optical splitter 21- (n + 1), the optical connector 24- (n + 1) a, and the optical connector 24-1b. Input to port n + 1. The standby system of the output optical signal 1 is taken out from the output port 1 of the 2n × 2n optical switch module 30b via the optical connectors 25-1a and 25- (n + 1) b. Similarly, the standby system for the output optical signals 2 to n is taken out from the output ports 2 to n of the 2n × 2n optical switch module 30b. The working system of the output optical signal (n + 1) to be added is a 2n × 2n optical switch module 30a via the output optical switch 22- (n + 1), the optical connector 25- (n + 1) a, and the optical connector 25-1b. Taken from output port n + 1.

  That is, the working systems of the input optical signals 1 to n are connected to the input ports 1 to n of the 2n × 2n optical switch module 30a, and the standby system is connected to the input ports 1 to n of the 2n × 2n optical switch module 30b. The active system of the input optical signal (n + 1) to be added is connected to the input port (n + 1) of the 2n × 2n optical switch module 30a, and the standby system is connected to the input port (n + 1) of the 2n × 2n optical switch module 31. The working systems of the output optical signals 1 to n are connected to the output ports 1 to n of the 2n × 2n optical switch module 30a, and the standby system is connected to the output ports 1 to n of the 2n × 2n optical switch module 30b. The working system of the output optical signal (n + 1) to be added is connected to the output port (n + 1) of the 2n × 2n optical switch module 30a, and the standby system is connected to the output port (n + 1) of the 2n × 2n optical switch module 30b.

  By the way, when the conventional n × n optical cross-connect device having the active system and the standby system shown in FIG. 12 is expanded to 2n × 2n, the n × n optical switch modules 10 and 11 are of the 2n × 2n type. However, instantaneous interruption of the working optical signal at the time of replacement is inevitable. On the other hand, in the configuration of the present embodiment, it is possible to cope with the expansion by changing the connection of the optical connectors on the standby side of the input optical signals 1 to n and the output optical signals 1 to n. Signal interruption etc. can be avoided.

The figure which shows 1st Embodiment of the optical cross-connect apparatus of this invention. The figure which shows 2nd Embodiment of the optical cross-connect apparatus of this invention. The figure which shows 3rd Embodiment of the optical cross-connect apparatus of this invention. 1 is a diagram illustrating a first configuration example of an optical switch module 30. FIG. The figure which shows the 2nd structural example of the optical switch module 30. FIG. The figure which shows the 3rd structural example of the optical switch module 30. FIG. The figure which shows 5th Embodiment of the optical cross-connect apparatus of this invention. The figure which shows 5th Embodiment of the optical cross-connect apparatus of this invention. The figure which shows the structural example of an optical cross-connect apparatus. The figure which shows the structural example of the optical cross-connect apparatus used for a wavelength division multiplexing optical transmission system. The figure which shows the structural example of the optical cross-connect apparatus used for a wavelength division multiplexing optical transmission system. The figure which shows the structural example of the redundant system of an optical cross-connect apparatus.

Explanation of symbols

10,11 n × n optical switch module 12 wavelength demultiplexer 13 wavelength multiplexer 21 optical splitter 22 output optical switch 23 optical wavelength selective blocker 24,25 optical connector 26 optical coupler 30 2n × 2n light Switch module 31 2nm × 2nm optical switch module

Claims (10)

An optical switch module that has input ports 1 to 2n (n is an integer of 2 or more) and output ports 1 to 2n, and performs cross-connection of optical signals between 2n × 2n input / output ports;
Each of the input optical signals 1 to n is branched into two, each one of the input optical signals 1 to n is connected to the input ports 1 to n of the optical switch module, and each of the other input optical signals 1 to n is connected to the optical switch module N optical branching devices connected to input ports (n + 1) to 2n of
Select one of the output optical signals from the output ports 1 to n of the optical switch module and the output optical signals from the output ports (n + 1) to 2n of the optical switch module and output them as output optical signals 1 to n Output light switch,
In the optical switch module, the input ports 1 to n and the output ports 1 to n are used as active systems, and the input ports (n + 1) to 2n and the output ports (n + 1) to 2n are used as standby systems. For the working path between the port i (i is an integer from 1 to n) and the output port j (j is an integer from 1 to n), the backup system of the input port (i + n) and the output port (j + n) In addition to the path, it is possible to set a backup path for the input port i and the output port (j + n) and a backup path for the input port (i + n) and the output port j.
The optical cross-connect device, wherein the output optical switch is configured to switch an output optical signal j in accordance with switching between the output port j and the output port (j + n) in the optical switch module. An optical switch module having an input port of 1 to 2 nm (n and m are integers of 2 or more) and an output port of 1 to 2 nm, and performing cross-connection of optical signals between 2 nm × 2 nm input and output ports;
M optical branching devices each bifurcating the input wavelength multiplexed optical signals S1 to Sm;
Each one of the input wavelength multiplexed optical signals S1 to Sm branched by the m optical splitters is demultiplexed into m sets of optical signals having wavelengths λ1 to λn, and the input port 1 of the optical switch module is set for each set. A first m wavelength demultiplexer connected to ~ nm;
The other input wavelength multiplexed optical signals S1 to Sm branched by the m optical branching devices are demultiplexed into m sets of optical signals of wavelengths λ1 to λn, and the input ports of the optical switch module ( nm + 1) to 2 nm, the second m wavelength demultiplexers connected to
First m wavelength multiplexers for respectively combining output optical signals of m sets of wavelengths λ1 to λn output from the output ports 1 to nm of the optical switch module;
Second m wavelength multiplexers that respectively combine m sets of output optical signals of wavelengths λ1 to λn output from output ports (nm + 1) to 2 nm of the optical switch module;
The wavelength multiplexed optical signal output from the first m wavelength multiplexers and the wavelength multiplexed optical signal output from the first m wavelength multiplexers are respectively combined to output an output wavelength multiplexed optical signal. M optical couplers outputting as S1 to Sm;
Between the m optical splitters and the second m wavelength demultiplexers, or between the second m wavelength multiplexers and the m optical couplers, An optical wavelength selective blocker that passes an optical signal of a wavelength and blocks an optical signal of another wavelength;
In the optical switch module, the input ports 1 to nm and the output ports 1 to nm are used as active systems, and the input ports (nm + 1) to 2 nm and the output ports (nm + 1) to 2 nm are used as standby systems. For the working path between the port i (i is an integer of 1 to nm) and the output port j (j is an integer of 1 to nm), a backup system of the input port (i + nm) and the output port (j + nm) In addition to the path, it is possible to set a backup path for the input port i and the output port (j + nm) and a backup path for the input port (i + nm) and the output port j.
The optical wavelength selection blocker, when selecting a backup path output to the standby output port (nm + 1) to 2 nm of the optical switch module, passes an optical signal having a wavelength corresponding to the output port. It is configured to block optical signals of all wavelengths when blocking optical signals of other wavelengths and not selecting a backup path output to the standby output port (nm + 1) to 2 nm of the optical switch module. Optical cross-connect device. The optical cross-connect device according to claim 2,
In place of the optical wavelength selective blocker, an optical signal having a wavelength that is not output among the standby path output to the standby output port (nm + 1) to 2 nm of the optical switch module is a wavelength-compatible output port. Are connected to different output ports, and the wavelength multiplexer functions as an optical wavelength selective blocker. The optical cross-connect device according to claim 2,
A wavelength converter is provided for each output port of the optical switch module,
A function of blocking the wavelength converter from an optical signal having a wavelength that is not output in the standby path output to the standby output port (nm + 1) to 2 nm of the optical switch module, instead of the wavelength selective blocker. An optical cross-connect device characterized by comprising: The optical cross-connect device according to claim 1,
The input / output ports of the optical switch module are divided into two areas, the active system and the standby system, so that a predetermined interval is not secured between the input port and the output port of the active system and the standby system in each area. An optical cross-connect device characterized by being arranged with regularity. In the optical cross-connect device according to any one of claims 2 to 4,
The input / output port of the optical switch module is divided into 2m areas for each wavelength multiplexed optical signal, and the input port and the output port corresponding to each wavelength in the 2m areas are at least not adjacent between the same wavelengths. An optical cross-connect device characterized in that it is arranged with regularity so as to ensure an interval of. In the optical cross-connect control method for switching between the active system and the standby system in the optical cross-connect device according to claim 1,
In the optical switch module, the input ports 1 to n and the output ports 1 to n are used as active systems, and the input ports (n + 1) to 2n and the output ports (n + 1) to 2n are used as standby systems. For the working path between the port i (i is an integer from 1 to n) and the output port j (j is an integer from 1 to n), the backup system of the input port (i + n) and the output port (j + n) In addition to the path, the backup path of the input port i and the output port (j + n) and the backup path of the input port (i + n) and the output port j are set.
The optical cross-connect control method, wherein the output optical switching unit switches an output optical signal j according to switching of the output port j and the output port (j + n) in the optical switch module. An optical cross-connect control method for switching between an active system and a standby system in the optical cross-connect device according to claim 2,
In the optical switch module, the input ports 1 to nm and the output ports 1 to nm are used as active systems, and the input ports (nm + 1) to 2 nm and the output ports (nm + 1) to 2 nm are used as standby systems. For the working path between the port i (i is an integer of 1 to nm) and the output port j (j is an integer of 1 to nm), a backup system of the input port (i + nm) and the output port (j + nm) In addition to the path, the backup path of the input port i and the output port (j + nm) and the backup path of the input port (i + nm) and the output port j are set.
The optical wavelength selection blocker, when selecting a backup path output to the standby output port (nm + 1) to 2 nm of the optical switch module, passes an optical signal having a wavelength corresponding to the output port. An optical signal characterized by blocking optical signals of other wavelengths and blocking optical signals of all wavelengths when the standby path output to the standby system output port (nm + 1) to 2 nm of the optical switch module is not selected. Cross-connect control method. The optical cross-connect control method according to claim 8,
Of the standby path output to the standby output port (nm + 1) to 2 nm of the optical switch module, an optical signal having a wavelength that is not output is connected to an output port different from the wavelength-compatible output port, and the wavelength An optical cross-connect control method characterized by causing a multiplexer to function as an optical wavelength selective blocker. In the optical cross-connect control method for adding an optical cross-connect device corresponding to the active system and the standby system according to claim 1 or 2,
The optical switch module is a first optical switch module, and a second optical switch module having the same configuration is used.
The optical signal and optical signal connected to the standby input port and output port of the first optical switch module are switched to the active input port and output port of the second optical switch module, and
An optical cross-connect control method, comprising: connecting an additional optical signal to a standby input port and output port of the first optical switch module.

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