JP5322058B2 - Hierarchical optical path cross-connect equipment - Google Patents

Description

  The present invention relates to a hierarchical optical path cross-connect device that functions as a relay node of an optical path network.

  In optical path networks, multi-layer optical path networks using wavelength group paths have been proposed in response to the increase in the number of ports and switch scale of optical cross-connect devices as the number of optical paths (wavelength paths) increases. . In this multi-layer optical path network, wavelength division multiplexing (in which a plurality of wavelengths respectively corresponding to a plurality of wavelength channels (wave channels or optical paths) divided every 100 GHz in a predetermined communication wavelength band are combined) For each set in which a plurality of WDM (Wavelength Division Multiplexing) lights, that is, wavelength groups are combined, they are transmitted in parallel via a plurality of paths (optical fibers).

  In each relay node of such a multi-layer optical path network, a plurality of sets of wavelength groups transmitted via optical fibers are routed in units of wavelength groups (in units of wavelength groups to optical fibers in a predetermined transmission direction). A path switching function to switch the path), a plurality of wavelengths (channels) included in each transmitted wavelength group are separated as necessary, and a predetermined wavelength is divided into an electrical signal and an optical signal in units of wavelengths. Drop function (node termination function) that outputs a wavelength to the electric layer EL for performing signal conversion between the two, and a wavelength group that converts the signal from the electric layer into a signal of a predetermined wavelength and includes the wavelength of the predetermined wavelength The add function (node start function) for transmitting the wavelength group to a predetermined path by combining the wavelength group and the plurality of wavelengths (channels) included in each transmitted wavelength group are separated, and a new predetermined wavelength is added. Forming a set of wavelength groups A grooming function of transmitting a long group units to a predetermined route is required. For example, an optical path cross-connect device disclosed in Patent Document 1 is an example.

JP 2008-252664 A

  For example, as shown in FIG. 16, M wavelength groups are respectively input via K input-side optical fibers Fi1 to FiK, and K (band) in the band (wavelength group) path cross-connect section BXC. Wavelength groups for routing to each output wavelength optical fiber Fo1 to FoK and performing routing in wavelength units with a predetermined add / drop rate y from the band (wavelength group) path cross-connect unit BXC to the wavelength path cross-connect unit While adding / dropping to the WXC in units of wavelength groups, the wavelength path cross-connect unit WXC decomposes N wavelengths included in the one wavelength group and performs a predetermined add to the electrical layer EL in units of wavelengths. A floor configured to add / drop at the / drop rate z and to route (groom) a newly formed wavelength group from a predetermined wavelength. Of the optical path cross-connect device is configured as a relay node in an optical path network. The electrical layer EL is provided with a router and the like, and has a function of performing signal conversion between an optical signal transmitted via a wavelength channel in wavelength units and an electrical signal of a terminal device.

  In the hierarchical optical path cross-connect device shown in FIG. 16, in the band (wavelength group) path cross-connect unit BXC, the number of input fibers and output fibers connected to the optical path network is K respectively, M is the number of wavelength groups, N is the number of wavelengths in the wavelength group, y is the add / drop rate in units of wavelength groups from the bandpass cross-connect unit BXC to the wavelength path cross-connect unit WXC, and electricity is supplied from the wavelength path cross-connect unit WXC. If the add / drop rate in units of wavelengths to the layer EL is z, the bandpass cross-connect unit BXC must be provided with (K + yK) optical couplers and wavelength group selection switches WBSS. The unit BXC must be composed of a relatively large number of optical couplers and an expensive wavelength group selection switch WBSS. There is a drawback that the size is large and the apparatus is expensive.

  The present invention has been made in the background of the above circumstances, and its object is to reduce the number of expensive wavelength group selective switches WBSS, reduce the size of the device, and reduce the cost of the device. An object of the present invention is to provide a hierarchical optical path cross-connect device for a path network.

  As a result of various studies on the background of the above circumstances, the present inventor has found that the bandpass cross-connect unit BXC of the conventional hierarchical optical cross-connect device described above is an optical coupler for switching the route of wavelength groups and wavelength group selection. The switch WBSS, the optical coupler for the drop function or the add function between the wavelength group and the wavelength, and the wavelength group selection switch WBSS were provided, but the drop function or the add function between the wavelength group and the wavelength was bandpassed. It has been found that the number of wavelength group selection switches WBSS can be greatly reduced by separating from the cross-connect unit BXC and performing, for example, the wavelength path cross-connect unit WXC. The present invention has been made based on such knowledge.

  That is, the gist of the invention according to claim 1 for achieving the object is as follows: (a) a wavelength group path cross-connect unit that performs switching in units of wavelength groups composed of a plurality of wavelengths; and switching in units of wavelengths. A wavelength path cross-connect unit for performing the arrangement as a relay node of an optical path network in which a transmission path is configured by a bundle of a plurality of optical fibers each transmitting a set of wavelength groups obtained by combining a predetermined number of the wavelength groups A route switching process for switching a plurality of wavelength groups transmitted via the input side optical fiber in units of wavelength groups, and included in the plurality of wavelength groups transmitted via the input side optical fiber. The wavelength processing is performed by switching the route in units of wavelengths and recombining the wavelengths between the wavelength groups, and the wavelengths included in the multiple wavelength groups transmitted through the input side optical fiber are wavelength units. so A hierarchical optical path cross-connect device that performs drop processing that is terminated and output to an electrical layer, wherein (b) the wavelength unit grooming in the wavelength path cross-connect unit or the wavelength path cross-connect unit and termination processing unit In order to execute processing and drop processing, a plurality of sets of wavelength groups input via the input-side optical fiber are input via the input-side optical fiber before reaching the wavelength group path cross-connect unit. There is provided a grooming / termination demultiplexing unit that demultiplexes a plurality of wavelength groups or separates wavelengths included in the wavelength groups and supplies them directly to the wavelength path cross-connect unit.

  Further, the gist of the invention according to claim 2 for achieving the above object is that (c) a wavelength group path cross-connect unit that performs switching in units of wavelength groups composed of a plurality of wavelengths, and switching in units of wavelengths. A wavelength path cross-connect unit for performing the arrangement as a relay node of an optical path network in which a transmission path is configured by a bundle of a plurality of optical fibers each transmitting a set of wavelength groups obtained by combining a predetermined number of the wavelength groups A route switching process for switching a plurality of wavelength groups transmitted via the input side optical fiber in units of wavelength groups, and included in the plurality of wavelength groups transmitted via the input side optical fiber. Switching the path for each wavelength, switching the path for each wavelength, and switching the path for each wavelength, and selecting the output side fiber. (D) After the grooming process and the start-end process in units of wavelengths executed in the wavelength path cross-connect unit or the wavelength path cross-connect unit and the start-end processing unit. A wavelength group multiplexing unit after grooming / starting processing for directly multiplexing the wavelength group to the wavelength group output from the wavelength group path cross-connect unit.

  The gist of the invention according to claim 3 is that, in the invention according to claim 1 or 2, (e) the wavelength path cross-connect unit includes a wavelength selective switch that performs switching in units of wavelengths, and The wavelength group path cross-connect unit has a wavelength group selection switch that performs switching in units of wavelength groups.

  Further, the gist of the invention according to claim 4 is that, in the invention according to claim 3, (f) the wavelength selective switch of the wavelength path cross-connect unit corresponds to the input side optical fiber or the output side optical fiber. The wavelength group selection switch of the wavelength group path cross-connect unit is provided corresponding to the input side optical fiber or the output side optical fiber.

  The gist of the invention according to claim 5 is that, in the invention according to claim 4, (g) the wavelength path cross-connect unit includes the wavelength selective switch on one of an input side and an output side thereof, The wavelength group path cross-connect unit includes the wavelength group selection switch on one of its input side and output side.

  Further, the gist of the invention according to claim 6 is that, in the invention according to claim 1, (h) the grooming / termination demultiplexing section is constituted by an optical coupler or a wavelength selective switch. is there.

  The gist of the invention according to claim 7 is that, in the invention according to claim 2, (i) the wavelength group multiplexing unit after the grooming / starting processing is constituted by an optical coupler or a wavelength selective switch. There is.

  According to the hierarchical optical path cross-connect device of the invention according to claim 1, in order to execute the grooming process and the drop process in units of wavelengths in the wavelength path cross-connect unit or the wavelength path cross-connect unit and the termination processing unit Before the plurality of wavelength groups input via the input side optical fiber reach the wavelength group path cross-connect section, the plurality of wavelength groups input via the input side optical fiber are demultiplexed. Alternatively, since a demultiplexing unit for grooming / termination processing that separates wavelengths included in the wavelength group and supplies them directly to the wavelength path cross-connect unit is provided, grooming processing and termination in wavelength units in the wavelength group path cross-connect unit The wavelength group selection switch that selects the wavelength group to be sent to the wavelength path cross-connect unit for processing is not required. It is possible to reduce the expensive number of waveband-selective switch group path cross-connect unit, and apparatus becomes small device size becomes considerably less expensive.

  According to the hierarchical optical path cross-connect device of the invention according to claim 2, after the grooming processing in the wavelength unit and the start end performed in the wavelength path cross-connect unit or the wavelength path cross-connect unit and the start end processing unit Since the wavelength group after processing is provided with a wavelength group multiplexing unit that directly combines the wavelength group output from the wavelength group path cross-connect unit with the wavelength group after start processing, grooming processing in the wavelength group path cross-connect unit and A wavelength group selection switch is not required to switch the route by combining the wavelengths sent from the wavelength path cross-connect unit for the start processing into the wavelength group, so an expensive wavelength group in the wavelength group path cross-connect unit The number of selection switches can be reduced, the scale of the apparatus is reduced, and the apparatus is significantly cheaper.

  Here, preferably, the wavelength path cross-connect unit includes a wavelength selection switch that performs switching in units of wavelengths, and the wavelength group path cross-connect unit includes a wavelength group selection switch that performs switching in units of wavelength groups. It is to be a thing. Preferably, the wavelength selection switch of the wavelength path cross-connect unit is provided corresponding to the input side optical fiber or the output side optical fiber, and the wavelength group selection switch of the wavelength group path cross-connect unit is It is provided corresponding to the input side optical fiber or the output side optical fiber. In this way, the number of wavelength group selection switches in the wavelength group path cross-connect unit can be reduced as much as possible.

  Preferably, the wavelength path cross-connect unit includes the wavelength selective switch on one of an input side and an output side, and the wavelength group path cross-connect unit includes the wavelength on one of the input side and the output side. A group selection switch is provided. In this way, the number of wavelength group selection switches in the wavelength group path cross-connect unit can be reduced as much as possible.

  Preferably, the grooming / termination demultiplexing unit includes an optical coupler or a wavelength selective switch. Preferably, the grooming / starting end post-wavelength wavelength group combining unit includes an optical coupler or a wavelength selective switch. In this way, in the demultiplexing unit for grooming / termination processing or the wavelength group multiplexing unit after grooming / starting end processing, an optical coupler or wavelength selective switch that is significantly less expensive than the wavelength group selective switch is used. It will be even cheaper.

It is a conceptual diagram for demonstrating the principal part structure of the optical path cross-connect apparatus arrange | positioned as a node apparatus of the optical path network of one Example of this invention. It is a figure explaining the relationship between the wavelength group of the optical signal transmitted with an optical fiber in the optical path cross-connect apparatus of FIG. 1, and the wavelength which comprises it, Comprising: The mutually continuous 16 selected from continuous wavelengths It is a figure explaining the example in which eight (group) wavelength groups by which one wavelength group was each set for every wavelength (channel) were formed. FIG. 7 is a diagram for explaining the relationship between a wavelength group of optical signals transmitted through an optical fiber and wavelengths constituting the optical signal in the optical path cross-connect device of FIG. Eight (group) wavelength groups each having one wavelength group set from the wavelength are shown. It is a figure explaining the optical coupler provided in the optical path cross-connect apparatus of FIG. It is a figure explaining the optical coupler provided in the optical path cross-connect apparatus of FIG. It is a figure explaining the wavelength selection switch provided in the optical path cross-connect apparatus of FIG. It is a figure explaining the wavelength group selection switch provided in the optical path cross-connect apparatus of FIG. The number of wavelength group selection switches provided in the optical path cross-connect device of FIG. 1 when the add / drop rate y is changed is compared with the number of wavelength group selection switches provided in the optical path cross-connect device of FIG. FIG. It is a figure equivalent to FIG. 1 which shows the structure of the optical path cross-connect apparatus of the other Example of this invention as Example 2. FIG. FIG. 10 is a diagram corresponding to FIG. 1 and illustrating the configuration of an optical path cross-connect device according to another embodiment of the present invention as a third embodiment. FIG. 10 is a diagram corresponding to FIG. 1 and showing the configuration of an optical path cross-connect device according to another embodiment of the present invention as Embodiment 4. FIG. 10 is a diagram corresponding to FIG. 1 and showing the configuration of an optical path cross-connect device of another embodiment of the present invention as a fifth embodiment. FIG. 11 is a diagram corresponding to FIG. 1 and showing the configuration of an optical path cross-connect device of another embodiment of the present invention as Embodiment 6. FIG. 10 is a diagram corresponding to FIG. 1 and showing the configuration of an optical path cross-connect device of another embodiment of the present invention as Embodiment 7. FIG. 10 is a diagram corresponding to FIG. 1 and showing the configuration of an optical path cross-connect device of another embodiment of the present invention as an eighth embodiment. It is a figure explaining the structure of the conventional optical path cross-connect apparatus.

  FIG. 1 is a relay node of an optical path network, and shows a block configuration of a main part of a hierarchical optical path cross-connect device (hereinafter referred to as an optical path cross-connect device) 10 according to an embodiment of the present invention. . In the optical path network, an optical signal is transmitted through a bundle of optical fibers functioning as a wavelength group path of the optical path network, for example, a bundle of K optical fibers. The optical signal is obtained by combining, for example, N light beams of a plurality of wavelengths respectively corresponding to a plurality of wavelength channels (wave channels or light paths) divided every 100 GHz of a predetermined communication wavelength band. Wavelength Division Multiplexing (WDM) light, that is, one wavelength group WB is configured, and the wavelength group WB includes one set of M, and each of the plurality of wavelength groups WB that configure each set includes It is transmitted for each optical fiber (wavelength group transmission path). That is, in the optical path cross-connect device 10, the wavelength groups WB11 to WB1M, the wavelength groups WB21 to WB2M,..., The wavelength groups WBK1 to WBKM are respectively connected to the K input side optical fibers Fi1, Fi2,. Wavelength groups WB11 to WB2M, wavelength groups WBK1 to WBKM are connected in parallel and routed in parallel through K output optical fibers Fo1, Fo2,. Output in parallel via each. K, M, and N are integers, for example, K = 8, M = 8, and N = 16.

  Here, for example, the wavelengths of the wavelength channels included in the wavelength group B11 are λ111 to λ11N, the wavelengths of the wavelength channels included in the wavelength group B12 are λ121 to λ12N, and the wavelengths of the wavelength channels included in the wavelength group B1M are λ1M1 to λ1MN, the wavelengths of the wavelength channels included in the wavelength group BKM are λKM1 to λKMN, but these wavelengths, for example, λ121 to λ12N may be sequentially increased or dispersively. It may be. 2 and 3 show a configuration example of the wavelength λ constituting one set of wavelength groups transmitted through one optical fiber. In the example of FIG. 2, M (8) (group) wavelength groups WB1 in which one wavelength group is set for each of N consecutive wavelengths (N = 16) selected from consecutive wavelengths. ~ WB8 is shown. In the example of FIG. 3, M (8) (group) wavelength groups WB1 to WB8 each having one wavelength group set from 16 wavelengths dispersively selected from continuous wavelengths are shown.

  In FIG. 1, the optical path cross-connect device 10 includes wavelength groups WB11 to WB1M, wavelength groups WB21 to WB2M,..., Wavelength groups WBK1 to which input side optical fibers Fi1, Fi2,. A function for performing route switching processing (routing processing in units of wavelength groups) for each wavelength group at the wavelength group level WBL, and the transmitted wavelength groups WB11 to WB1M, wavelength groups WB21 to WB2M,. A plurality of wavelengths (channels) included in each of WBK1 to WBKM are separated as necessary, and a predetermined wavelength is converted between an electrical signal and an optical signal in units of wavelength in units of wavelengths at the wavelength level WLL. A drop process (termination process) function to output to the electric layer EL for performing the signal, and a signal of a predetermined wavelength from the electric layer EL in units of wavelengths in the wavelength level WLL. An add processing (start processing) function for forming a wavelength group including the wavelength of the wavelength and transmitting the wavelength group to a predetermined path, and the transmitted wavelength groups WB11 to WB1M, wavelength groups WB21 to WB2M,... A grooming processing function that separates a plurality of wavelengths (channels) included in each of the groups WBK1 to WBKM, forms a new set of wavelength groups of a predetermined wavelength, and transmits them to a predetermined path in units of wavelength groups; It has been.

  Therefore, the optical path cross-connect device 10 includes the wavelength path cross-connect unit WXC that performs the termination process, the start-end process, and grooming for each wavelength, and the band-pass cross-connect unit BXC that performs the path switching process for each wavelength group. In order to separate the grooming process and the termination process from the bandpass cross-connect unit BXC, the wavelengths of the K groups (K sets) respectively input through the input side optical fibers Fi1, Fi2,. A grouping / termination demultiplexing unit GE that demultiplexes the groups WB11 to WB1M, WB21 to WB2M,... WBK1 to WBKM and supplies them to the wavelength path cross-connect unit WXC.

  The grooming / termination demultiplexing unit GE is provided in each of the K input-side optical fibers Fi1, Fi2,... FiK, and wavelength groups WB11 to WB1M and wavelength groups WB21 to WB2M toward the bandpass cross-connect unit BXC. ,... Are provided with optical couplers PCi1, PCi2,... PCiK that demultiplex the wavelength groups WBK1 to WBKM and supply them to the wavelength path cross-connect unit WXC, respectively. These optical couplers PCi1, PCi2,..., PCiK are so-called 1 × 2 optical couplers having one input port and two output ports, and outputting input light in parallel from two output ports, respectively.

  The wavelength path cross-connect unit WXC includes a plurality of wavelength groups WB11 to WB1M, wavelength groups WB21 to WB2M, wavelength groups WBK1 to WBKM, which are demultiplexed by the optical couplers PCi1, PCi2,. K optical couplers PCw1, PCw2,..., PCwK, which are received and demultiplexed in units of wavelengths, and add input side optical multiplexers composed of, for example, general arrayed waveguide gratings, that is, start-end processing units AWGa1 to AWGazyK ZyK start-end (add) input optical couplers PCa1 to PCazyK for receiving a plurality of wavelengths received from the electric layer EL via the optical layer EL and outputting them at a ratio of a predetermined add / drop rate z (≦ 1), and light Coupler PCw1, PCw2,... Drop output side light composed of a general arrayed waveguide grating with a predetermined wavelength selected in wavelength units at a predetermined add / drop rate z out of a plurality of wavelengths output from PCwK Splitter Wavelength selection switches WSSd1 to WSSazyK for zyK drop output to be output to the electrical layer EL via the termination processing units AWGd1 to AWGdzyK, and wavelength selection switches WSSw1, WSSw2,. And has. The add / drop rate z is a ratio of a predetermined wavelength unit between the electrical layer EL and the wavelength path cross-connect unit WXC, and y (≦ 1) is the same as the wavelength path cross-connect unit WXC. This is an add / drop rate in units of wavelength groups indicating a preset delivery ratio with the bandpass cross-connect unit BXC. The optical couplers PCw1, PCw2,..., PCwK are composed of, for example, 1 × (yK + zyK) so-called star type optical couplers having yK + zyK output ports for one input port. The start-end input optical couplers PCa1 to PCazyK are composed of, for example, 1 × (1 + yK) optical couplers. Further, the termination output wavelength selective switches WSSd1 to WSSdzyK are composed of, for example, 1 × (yK) wavelength selective switches. Further, the wavelength group forming wavelength selective switches WSS1, WSS2,..., WSSyK are composed of, for example, 1 × (K + zyK) wavelength selective switches.

  The band-pass cross-connect unit BXC is transmitted through K input-side optical fibers Fi1, Fi2,... FiK and passes through optical couplers PCi1, PCi2,. K groups of wavelength groups WB11 to WB1M, WB21 to WB2M,... For forming the wavelength groups of the K optical couplers PCb1, PCb2,..., PCbK to which WBK1 to WBKM are input and the wavelength path cross-connect unit WXC Wavelength selective switches WSS1, WSS2,... YK new wavelength group joining optical couplers PCe1, PCe2,..., PCeyK that receive the wavelength groups output from WSSyK, and their optical couplers PCb1, PCb2,.・ Receiving wavelength groups output from PCbK and new wavelength group adding optical couplers PCe1, PCe2,... PCeyK, K output optical fibers Fo1, Fo2,. There are provided K wavelength group selection switches WBSS1, WBSS2,... WBSK that output in units of wavelength groups. The optical couplers PCb1, PCb2,... PCbK, and the new wavelength group addition optical couplers PCe1, PCe2,..., PCeyK are constituted by, for example, 1 × K so-called star type optical couplers. The new wavelength group adding optical couplers PCe1, PCe2,..., PCeyK are constituted by, for example, 1 × K so-called star type optical couplers. The wavelength group selection switches WBSS1, WBSS2,... WBSK are composed of, for example, a K × 1 wavelength group selection switch. The bandpass cross-connect unit BXC is composed of, for example, a (K + yK) × 1 wavelength group selection switch.

  The optical couplers PCi1 to PCiK, PCw1 to PCwK, PCa1 to PCazyK, PCb1 to PCbK, PCe1 to PCeyK are, for example, those obtained by locally melting and optically coupling the end portions or intermediate portions of a plurality of optical fibers, It is configured by optically coupling multiple optical fibers using a Mach-Zehnder interferometer, etc. None of them have wavelength selectivity, and a part of the input light is demultiplexed into multiple ports Are output in parallel, or a plurality of input lights are combined and output.

  FIGS. 4 and 5 illustrate the optical function or property of the optical coupler PC. FIG. 4 shows an example of an optical coupler having one input port and three output ports. . In the optical coupler illustrated in FIG. 4, when an optical signal including eight wavelength channels from λ1 to λ8 is input, the optical signal including eight wavelength channels from λ1 to λ8 is directly divided in parallel. The same optical signal is output from each of the three output ports. FIG. 5 shows an example of an optical coupler having three input ports and one output port. In the optical coupler illustrated in FIG. 5, an optical signal including a wavelength channel of λ2, an optical signal including two wavelength channels of λ1 and λ4, and an optical signal including a wavelength channel of λ3 are input to three input ports, respectively. Then, they are combined and output from one output port as an optical signal including wavelength channels of λ1 to λ4. Such an optical coupler PC can also be used in the reverse direction.

  The termination output wavelength selective switches WSSd1 to WSSdzyK, the wavelength selective switches WSS1 to WSSSyK, and the wavelength group forming wavelength selective switches WBSS1 to WBSK are composed of, for example, a diffraction grating, an arrayed waveguide grating, and the like. A spectroscope that splits light in wavelength units or wavelength group units, a collimator array, an MEMS mirror array, and the like, and the light in the wavelength units or wavelength group units dispersed by the spectroscope to a desired waveguide or optical fiber. It is comprised similarly from the MEMS optical switch to propagate selectively. In the MEMS mirror, a micromirror supported rotatably by a torsion bar is driven by an electrostatic attraction force by an electrode disposed in the vicinity thereof. The wavelength selective switch described in Japanese Patent Application Laid-Open No. 2009-511956 is an example of the wavelength selective switch WSS.

  6 and 7 illustrate the optical functions or properties of the wavelength selective switch WSS and the wavelength group selective switch WBSS. FIG. 6 shows a wavelength selection having one input port and four output ports. An example of a switch WSS is shown. In the wavelength selective switch WSS illustrated in FIG. 6, when an optical signal including eight wavelength channels λ1 to λ8 is input, for example, eight wavelengths λ1 to λ8 are set according to an electrical command signal. An optical signal including wavelength channels of λ1 and λ4, an optical signal including wavelength channels of λ2, λ3, and λ7, an optical signal including wavelength channels of λ6, and an optical signal including wavelength channels of λ5 and λ8. Are selectively output from each of the four output ports. FIG. 7 shows an example of a wavelength group selective switch WBSS having one input port and four output ports. In the wavelength group selection switch WBSS illustrated in FIG. 7, when an optical signal including four wavelength groups WB1 to WB4 is input, for example, the four wavelength groups WB1 to WB4 are included according to an electrical command signal. Of the optical signals, an optical signal including the wavelength groups WB1 and WB2, an optical signal including the wavelength group WB3, an optical signal not including the wavelength group, and an optical signal including the wavelength group WB4 are respectively output from the four output ports. Output selectively. Such wavelength selective switch WSS and wavelength group selective switch WBSS can be output in any combination of wavelengths or any combination of wavelength groups, and can be used in the reverse direction.

  In the optical path cross-connect device 10 of the present embodiment configured as described above, the wavelength path cross-connect unit WXC or the wavelength path cross-connect unit WXC and the termination processing units AWGd1 to AWGdzyK perform grooming processing and drop processing in units of wavelengths. In order to execute, before a plurality of sets of wavelength groups input via the input side optical fibers Fi1, Fi2,... FiK reach the wavelength group selection switch WBSS of the bandpass cross-connect unit BXC, the input side Grooming / demultiplexing a plurality of sets of wavelength groups input through optical fibers Fi1, Fi2,..., FiK and supplying them directly to the wavelength path cross-connect unit WXC without passing through the band-pass cross-connect unit BXC. Since a demultiplexing unit GE for termination processing is provided, grooming processing and termination processing in units of wavelengths are performed. Therefore, it is not necessary to provide a wavelength group selection switch for selecting a wavelength group to be sent to the wavelength path cross-connect unit WXC in the band-pass cross-connect unit BXC. Therefore, an expensive wavelength group selection switch in the band-pass cross-connect unit BXC The number of WBSSs can be reduced, the device scale is reduced, the device is downsized, and the cost is greatly reduced. Generally, the optical coupler PC has a price of about 10,000 yen, for example, whereas the wavelength group selective switch WBSS has a price of about 1 million yen, for example, so reducing the number of wavelength group selective switches WBSS This is significant in that the optical path cross-connect device 10 is inexpensive.

  Incidentally, in FIG. 8, when K = 6, M = 8, and N = 8, the add / drop rate y between the bandpass cross-connect unit BXC and the wavelength path cross-connect unit WXC is changed. FIG. 7 is a diagram showing the number of wavelength group selection switches WBSS of the optical path cross-connect device 10 of this embodiment in comparison with the number of wavelength group selection switches WBSS of the conventional optical path cross-connect device shown in FIG. is there. The number of wavelength group selection switches WBSS in the conventional optical path cross-connect device shown in FIG. 16 increases as the add / drop rate y increases, whereas the wavelength group selection in the optical path cross-connect device 10 of the present embodiment. The number of switches WBSS is initially smaller than the number of wavelength group selection switches WBSS of the conventional optical path cross-connect device shown in FIG. 16, and does not change as the add / drop rate y increases, and y = 0.5. In some cases, the number of wavelength group selection switches WBSS can be reduced by about 33%.

  Further, according to the optical path cross-connect device 10 of the present embodiment, the wavelength path cross-connect unit WXC has the wavelength selection switch WSS that performs switching in units of wavelengths, and the band-pass cross-connect unit BXC has units of wavelengths. The wavelength group selection switch WBSS that performs switching is provided, and the wavelength group selection switch WBSS of the bandpass cross-connect unit BXC is used for switching the route of the wavelength group, the input side optical fibers Fi1 to FiK or the output side optical fiber. Since K pieces are provided corresponding to Fo1 to FoK, the number of wavelength group selection switches WBSS in the bandpass cross-connect unit BXC can be reduced as much as possible.

  Further, according to the optical path cross-connect device 10 of this embodiment, the wavelength path cross-connect unit WXC includes the wavelength selective switch WSS on one of the input side and the output side, and the band-pass cross-connect unit BXC Since the wavelength group selection switch WBSS is provided on one of the output side and the output side, the number of wavelength group selection switches WBSS in the bandpass cross-connect unit BXC can be reduced as much as possible.

  Also, according to the present embodiment, the grooming / termination branching unit GE is composed of the optical couplers PCi1 to PCiK, and therefore, in the grooming / termination branching unit GE, the wavelength group selection switch WBSS or the wavelength selection switch Since the optical coupler PC, which is significantly cheaper than the switch WSS, is used, the optical path cross-connect device 10 becomes even cheaper.

  Next, an optical path cross-connect device according to another embodiment of the present invention will be described. In the following description, parts common to the embodiments are denoted by the same reference numerals and description thereof is omitted.

  FIG. 9 shows a configuration of an optical path cross-connect device 20 according to another embodiment of the present invention. In FIG. 9, the optical path cross-connect device 20 is compared with the optical path cross-connect device 10 in that (a) the grooming / termination branching unit GE is inserted in the input side optical fibers Fi1 to FiK. Termination processing branching unit GE1 composed of 1 × 2 optical couplers PCie1 to PCieK and grooming processing composed of K 1 × 2 optical couplers PCig1 to PCigK inserted in the input side optical fibers Fi1 to FiK. (B) Instead of the zyK number of termination processing units AWGd1 to AWGdzyK, each of the signals from the termination processing branching unit GE1 is received and given to the electrical layer EL. K termination processing units AWGd1 to AWGdK that output at an add / drop rate zy are provided. (c) In the wavelength path cross-connect unit WXC, wavelength selection switches for termination output WSSd1 to WSSdzyK Is different in that it is removed, and the others are similarly configured.

  According to the optical path cross-connect device 20 of the present embodiment, a plurality of sets of wavelength groups input by the grooming / termination branching unit GE via the input-side optical fibers Fi1, Fi2,. A wavelength group that is demultiplexed and directly supplied to the wavelength path cross-connect unit WXC without passing through the band-pass cross-connect unit BXC, so that it is sent to the wavelength path cross-connect unit WXC for grooming processing and termination processing in units of wavelengths. Therefore, it is not necessary to provide the wavelength group selection switch WBSS in the bandpass cross-connect unit BXC, so that the grooming process and the termination process are separated from the bandpass cross-connect unit BXC. The same effect can be obtained. In addition, since the expensive terminal output wavelength selective switch WSSd provided in the wavelength path cross-connect unit WXC is removed, the cost of the optical path cross-connect device 20 is further reduced.

  FIG. 10 shows a configuration of an optical path cross-connect device 30 according to another embodiment of the present invention. 10, compared with the optical path cross-connect device 10, the optical path cross-connect device 30 includes: (a) K (zyK + 1) × 1 optical couplers PCo1˜ that are inserted in the output side optical fibers Fo1˜Fok. (B) The zyK start-end processing units AWGa1 to AWGazyK and the post-start-processed wavelength group combining unit GS1 are connected from the electrical layer EL. 1 × K start-end processing wavelength selective switch WSSa for selectively outputting a plurality of wavelengths to any one of the output side optical fibers Fo1 to FoK, and (c) a wavelength path cross-connect unit WXC. The difference is that the starting-end input optical couplers PCa1 to PCazyK are removed, and the rest is configured similarly.

  According to the optical path cross-connect device 30 of the present embodiment, a plurality of sets of wavelength groups input by the grooming / termination branching unit GE through the input side optical fibers Fi1, Fi2,. After being demultiplexed and directly supplied to the wavelength path cross-connect unit WXC without passing through the band-pass cross-connect unit BXC, the start-end processing is performed by the start-end processing wavelength selective switches WSSa1 to WSSazyK and the post-start-end wavelength group multiplexing unit GS1. Since the subsequent wavelengths are directly output to the output side optical fibers Fo1, Fo2,... FoK without going through the wavelength group selection switch WBSS, the wavelength path cross-connect unit is used for the grooming processing and termination processing in units of wavelengths. A wavelength group selection switch WBSS for selecting a wavelength group to be sent to the WXC is provided in the bandpass cross-connect unit BXC. Since bets becomes unnecessary, grooming process, will be starting processing and termination processing is disconnected from the band-pass cross-connect unit BXC, it is obtained the same effects as the above-described first embodiment.

  FIG. 11 shows a configuration of an optical path cross-connect device 40 according to another embodiment of the present invention. In FIG. 11, the optical path cross-connect device 40 is different from the optical path cross-connect device 10 in that (a) a signal from the termination processing demultiplexing unit GE is used instead of the zyK termination processing units AWGd1 to AWGdzyK. Are provided with K termination processing units AWGd1 to AWGdK that respectively receive and output to the electric layer EL at a predetermined add / drop rate zy, and (b) the grooming / termination processing branching unit GE is provided on the input side. Instead of the K 1 × 2 optical couplers PCi1 to PCiK inserted in the optical fibers Fi1 to FiK, the input side optical fibers Fi1 to FiK are inserted into the input side optical fibers Fi1 to FiK. The wavelength is selected from the optical signal transmitted by FiK, and is selectively output to any one of K optical couplers PCw1 to PCwK in the wavelength path cross-connect unit WXC in units of wavelengths, and the input side optical fibers Fi1 to It is composed of K 1 × 3 wavelength selective switches WSS that select a wavelength to be terminated from an optical signal transmitted through iK and selectively output it to any one of the termination processing units AWGd1 to AWGdK in units of wavelengths. (C) The wavelength path cross-connect unit WXC is different in that the wavelength selection switches WSSd1 to WSSdzyK for termination output are removed, and the other configurations are the same.

  According to the optical path cross-connect device 40 of the present embodiment, a plurality of sets of wavelength groups input by the grooming / termination branching unit GE via the input-side optical fibers Fi1, Fi2,. A wavelength group that is demultiplexed and directly supplied to the wavelength path cross-connect unit WXC without passing through the band-pass cross-connect unit BXC, so that it is sent to the wavelength path cross-connect unit WXC for grooming processing and termination processing in units of wavelengths. Therefore, it is not necessary to provide the wavelength group selection switch WBSS in the bandpass cross-connect unit BXC, so that the grooming process and the termination process are separated from the bandpass cross-connect unit BXC. The same effect can be obtained.

  FIG. 12 shows the configuration of an optical path cross-connect device 50 according to another embodiment of the present invention. In FIG. 12, the optical path cross-connect device 50 is similar to the optical path cross-connect device 10 in the same manner as the wavelength group multiplexing unit GS after the start end processing, instead of the (a) demultiplexing unit GE for the grooming / termination process. And (b) band pass, in which a wavelength group multiplexing unit GS after grooming / starting processing composed of K 2 × 1 optical couplers PCo1 to PCoK inserted in the output side optical fibers Fo1 to FoK is added. In the cross-connect section BXC, K 1 × (K + yK) wavelength group selection switches WBSS1 for receiving a plurality of wavelength groups transmitted via the K input-side optical fibers Fi1, Fi2,. , WBSS2,... WBSK is provided on the input side, and K K × 1 optical couplers PCb1, PCb2,... PCbK and yK K × 1 wavelength groups for receiving the wavelength groups output from them. drop Optical couplers PCe1, PCe2,..., PCeyK are provided on the output side, (c) In order to receive the wavelength group dropped from the bandpass cross connect unit BXC in the wavelength path cross connect unit WXC, yK 1 × (K + zyK) wavelength group forming wavelength selective switches WSS1, WSS2,... WSSSyK and 1 × K add-input wavelength selective switches WSSa1 to WSSazyK are provided on the input side and receive wavelengths from them. (K + zyK) × 1 optical couplers PCw1, PCw2,... PCwK for forming a wavelength group, and K × 1 termination (drop) output optical couplers PCd1 to PCw1 for outputting at a ratio of a predetermined add / drop rate z PCdzyK differs from PCdzyK in that it is provided on the output side, and the others are configured similarly. In the optical path cross-connect device 50 according to the present embodiment, the input side and the output side of the band-pass cross connect unit BXC and the wavelength path cross-connect unit WXC are inverted as compared with the optical path cross-connect device 10.

  According to the optical path cross-connect device 50 of the present embodiment, the wavelength group after the grooming process in units of wavelengths and the wavelength group after the start-end process are converted into a band-pass cross-connect unit by the wavelength group combining unit GS after grooming / starting end processing. Since the grooming process and the start-end process are separated from the bandpass cross-connect unit BXC by being output directly to the output side optical fibers Fo1 to FoK without going through the BXC, the wavelength is the same as in the first embodiment. There is an effect that the number of group selection switches WBSS is reduced and the apparatus is small and inexpensive.

  FIG. 13 shows a configuration of an optical path cross-connect device 60 according to another embodiment of the present invention. In FIG. 13, compared with the optical path cross-connect device 50, the optical path cross-connect device 60 includes (a) a wavelength group combining unit GS after grooming / starting end processing inserted in the input-side optical fibers Fo1 to FoK. And a post-grooming wavelength group combining unit GS1 composed of K 2 × 1 optical couplers PCog1 to PCogK, and K (zyK + 1) × 1 optical couplers PCos1 inserted in the input side optical fibers Fo1 to FoK. (B) zyK start-end processing units AWGa1 to AWGazyK and post-start-end wavelength group, including a grooming / start-end-processed wavelength group multiplex unit GE including a start-end-processed wavelength group combiner GS2 composed of PCosK 1 × K start-end processing wavelength selective switches WSSa1 to W that selectively output a plurality of wavelengths from the electrical layer EL directly to any one of the output side optical fibers Fo1 to FoK between the multiplexing unit GS2 That SazyK is provided, in (c) wave path cross-connect unit WXC, and differs in that the starting input wavelength selective switch WSSa1~WSSazyK is removed, others are configured similarly.

  According to the optical path cross-connect device 60 of the present embodiment, the wavelength group after the grooming process in units of wavelengths and the wavelength group after the start-end process are converted into the band-pass cross-connect unit by the wavelength group after the grooming / start-end process GS. Since the grooming process and the start-end process are separated from the bandpass cross-connect unit BXC by being output directly to the output side optical fibers Fo1 to FoK without passing through the BXC, the wavelength is the same as in the above-described fifth embodiment. There is an effect that the number of group selection switches WBSS is reduced and the apparatus is small and inexpensive.

  FIG. 14 shows the configuration of an optical path cross-connect device 70 according to another embodiment of the present invention. 14, compared with the optical path cross-connect device 50, the optical path cross-connect device 70 includes: (a) K 1 × 2 optical couplers PCie1 to PCieK inserted in the input-side optical fibers Fi1 to FiK. (B) In place of the zyK termination processing units AWGd1 to AWGdzyK, the signals from the termination processing demultiplexing unit GE1 are received and sent to the electric layer EL. K termination processing units AWGd1 to AWGdK that output at a predetermined add / drop rate zy are provided. (C) In the wavelength path cross-connect unit WXC, termination output optical couplers PCd1 to PCdzyK are removed. In other respects, the rest is configured similarly.

  According to the optical path cross-connect device 70 of the present embodiment, a plurality of sets of wavelength groups input through the input side optical fibers Fi1, Fi2,... The wavelength group and the start end after the grooming processing in units of wavelengths are directly supplied to the termination processing units AWGd1 to AWGdK without passing through the bandpass cross-connect unit BXC, and after the grooming / starting end wavelength group combining unit GS The processed wavelength group is directly output to the output-side optical fibers Fo1 to FoK without passing through the bandpass cross-connect unit BXC, so that the grooming process, the start end process, and the termination process are separated from the bandpass cross-connect unit BXC. Therefore, as in the fifth embodiment, the number of wavelength group selective switches WBSS is reduced and the apparatus is reduced in size and size. Effect is obtained in that less expensive.

  FIG. 15 shows a configuration of an optical path cross-connect device 80 according to another embodiment of the present invention. In FIG. 15, the optical path cross-connect device 80 is different from the optical path cross-connect device 50 in that (a) a signal from the termination processing demultiplexing unit GE is used instead of the zyK termination processing units AWGd1 to AWGdzyK. Are provided with K termination processing units AWGd1 to AWGdK that respectively receive and output to the electrical layer EL at a predetermined add / drop rate zy, and (b) are inserted into the input side optical fibers Fi1 to FiK. A wavelength is selected from the optical signals transmitted through the input side optical fibers Fi1 to FiK and selectively output to any one of the K wavelength selective switches WSSw1 to WSSwK in the wavelength path cross-connect unit WXC in units of wavelengths. At the same time, a wavelength to be terminated is selected from the optical signals transmitted through the input side optical fibers Fi1 to FiK, and is selectively output to any one of the termination processing units AWGd1 to AWGdK in units of wavelengths. (C) In the bandpass cross-connect unit BXC, optical couplers PCb1 to PCbK and PCd1 to PCdyK are provided, which are provided with a grooming / termination demultiplexing unit GE composed of 1 × 3 wavelength selective switch WSS. In addition, K pieces in the wavelength group combining unit GS after the grooming / starting end processing are performed from the K wavelength group selection switches WBSS1 to WBSK that respectively receive a plurality of sets of wavelength groups respectively transmitted from the input side optical fibers Fi1 to FiK. The optical switches PCo1 to PCoK are different from each other in that they are respectively output to the optical switches PCo1 to PCoK, and (d) in the wavelength path cross-connect unit WXC, the termination output optical couplers PCd1 to PCdzyK are removed. Yes.

  According to the optical path cross-connect device 80 of the present embodiment, a plurality of sets of wavelength groups input by the grooming / termination demultiplexing unit GE via the input-side optical fibers Fi1, Fi2,. Wavelength groups after being subjected to grooming processing in units of wavelengths by the wavelength group combining unit GS after being split and supplied directly to the wavelength path cross-connect unit WXC without passing through the band-pass cross-connect unit BXC In addition, the wavelength group after the start end process is directly output to the output side optical fibers Fo1 to FoK without passing through the band pass cross connect unit BXC, so that the grooming process, the start end process, and the end process are separated from the band pass cross connect unit BXC. Therefore, similar to the optical path cross-connect device 50 of the fifth embodiment, the wavelength group selection switch There is an effect that the number of the switches WBSS is reduced and the apparatus becomes small and inexpensive.

  As mentioned above, although one Example of this invention was described based on drawing, this invention is applied also in another aspect.

  For example, the optical path cross-connect device 10 according to the above-described embodiment is an optical path cross-connect device having a hierarchical (two-layer) configuration in which cross-connects are performed in wavelength group units and wavelength units at the wavelength group level WBL and the wavelength level WLL. However, it is applicable even if it is configured in three or more layers.

  Further, in the optical path cross-connect device 10 described above, the transmission is performed by the input side optical fibers Fi1, Fi2,... FiK and the output side optical fibers Fo1, Fo2,. Number of wavelength groups M, number of wavelengths N included in one wavelength group, add / drop rate y between wavelength group level WBL and wavelength level WLL, add / drop rate between wavelength level WLL and electrical layer EL z can be variously changed as necessary.

  In addition, although not illustrated one by one, the present invention can be variously modified without departing from the spirit of the present invention.

10, 20, 30, 40, 50, 60, 70, 80: Optical path cross-connect device (hierarchical optical path cross-connect device)
Fi1, Fi2,... FiK: Input side optical fiber Fo1, Fo2,... FoK: Output side optical fiber BXC: Band pass cross connect part (wavelength group path cross connect part)
WXC: Wavelength path cross-connect unit WBSS: Wavelength group selection switch WSS: Wavelength selection switch PC: Optical coupler AWGd: Termination processing unit AWGa: Start end processing unit

Claims (7)

  A set of wavelength groups, each having a wavelength group path cross-connect unit that performs switching in units of wavelength groups composed of a plurality of wavelengths, and a wavelength path cross-connect unit that performs switching in units of wavelengths, wherein a predetermined number of the wavelength groups are combined. Are arranged as a relay node of an optical path network in which a transmission path is composed of a bundle of a plurality of optical fibers each transmitting a plurality of wavelength groups transmitted through an input side optical fiber in a route by wavelength group unit. Route switching process for switching, and a switching process for switching wavelengths in wavelength units among wavelengths included in a plurality of sets of wavelength groups transmitted via the input side optical fiber to realize recombination of wavelengths between the wavelength groups And a layered optical path cross-connect device that performs a drop process of terminating wavelengths included in a plurality of sets of wavelength groups transmitted via the input-side optical fiber and outputting them to the electrical layer In order to perform the grooming process and the drop process in units of wavelengths in the wavelength path cross-connect unit or the wavelength path cross-connect unit and the termination processing unit, a plurality of sets input via the input side optical fiber Before the wavelength group reaches the wavelength group path cross-connect unit, the plurality of wavelength groups input via the input-side optical fiber are demultiplexed or the wavelengths included in the wavelength group are separated, and the wavelength path is separated. A hierarchical optical path cross-connect device comprising a grooming / termination demultiplexing unit that directly supplies to a cross-connect unit.   A set of wavelength groups, each having a wavelength group path cross-connect unit that performs switching in units of wavelength groups composed of a plurality of wavelengths, and a wavelength path cross-connect unit that performs switching in units of wavelengths, wherein a predetermined number of the wavelength groups are combined. Are arranged as a relay node of an optical path network in which a transmission path is composed of a bundle of a plurality of optical fibers each transmitting a plurality of wavelength groups transmitted through an input side optical fiber in a route by wavelength group unit. Route switching process for switching, and a switching process for switching wavelengths in wavelength units among wavelengths included in a plurality of sets of wavelength groups transmitted via the input side optical fiber to realize recombination of wavelengths between the wavelength groups And a hierarchized optical path cross-connect device that performs start processing for switching the path of a wavelength input from an electrical layer in units of wavelength, the wavelength path cross-connect unit or the wavelength path cross-connect unit Wavelength after grooming / starting edge processing that directly multiplexes the wavelength group after the grooming processing and after the starting edge processing performed in the sconnect unit and the start edge processing unit to the wavelength group output from the wavelength group path cross-connect unit. A hierarchical optical path cross-connect device comprising a group multiplexing unit.   The wavelength path cross-connect unit includes a wavelength selection switch that performs switching in units of wavelengths, and the wavelength group path cross-connect unit includes a wavelength group selection switch that performs switching in units of wavelength groups. The hierarchical optical path cross-connect device according to claim 1 or 2.   The wavelength selection switch of the wavelength path cross-connect unit is provided corresponding to the input-side optical fiber or the output-side optical fiber, and the wavelength group selection switch of the wavelength group path cross-connect unit is the input-side optical fiber or output 4. The hierarchical optical path cross-connect device according to claim 3, wherein the hierarchical optical path cross-connect device is provided corresponding to a side optical fiber.   The wavelength path cross-connect unit includes the wavelength selective switch on one of its input side and output side, and the wavelength group path cross-connect unit includes the wavelength group selection switch on one of its input side and output side The hierarchical optical path cross-connect device according to claim 4.   2. The hierarchized optical path cross-connect device according to claim 1, wherein the grooming / termination demultiplexing unit includes an optical coupler or a wavelength selective switch.   3. The hierarchized optical path cross-connect device according to claim 2, wherein the wavelength group multiplexing unit after the grooming / starting end processing is composed of an optical coupler or a wavelength selective switch.

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