JPH07162904A - Wavelength cross connect circuit and main wiring board - Google Patents

Abstract

PURPOSE:To multiplex a wavelength without any synthetic loss and to reduce the lowering of an optical signal level at the time of wavelength cross connect processing by providing a wavelength routing circuit behind a wavelength converter. CONSTITUTION:An input/output module is constituted by combining modules for which the output azimuth patterns of optical signals to arrive are fixedly set corresponding to their wavelengths. Tuners 601-603 select any arbitrary wavelength out of the optical signals with wavelengths lambda1-lambda3. Wavelength converters 604-606 convert it to respectively mutually different fixed output wavelengths. This wavelength converted optical signal is routed by a wavelength routing circuit 607. When the optical signals with the wavelengths lambda1-lambda3 are inputted from an input port 2, for example, those signals are respectively routed to output ports 3, 1 and 2. When the optical signals with the wavelength lambda1-lambda3 are oppositely inputted from the output port 1, those signals are respectively routed to input ports 1, 2 and 3 and in principle, this circuit is operated as a wavelength multiplexer/demultiplexer circuit with no loss.

Description

Detailed Description of the Invention

[0001]

The present invention is used in optical communication. In particular, it relates to a technology for collecting and wiring optical communication lines.

[0002]

2. Description of the Related Art A conventional example will be described with reference to FIGS. FIG. 9 is a block diagram of a conventional wavelength cross connect circuit. FIG. 10 is a block diagram of a conventional optical space switch circuit. The input lines 100 to 103 and the output lines 104 to 107 respectively have four wavelengths λ.
1 to λ4 are multiplexed. Arbitrary input line 100-1
03 optical signal of an arbitrary wavelength
It is converted into an optical signal of an arbitrary wavelength 107 and outputted.
The optical signals of the input lines 100 to 103 are branched links 108 to
Distributed by 111. Optical space switch circuit 112-
115 have 4 inputs and 4 outputs, respectively, and are arbitrary one-to-one
Besides connections, one input can be connected to up to four outputs. The tuners 116 to 131 can select any one wavelength from the input optical signals. The wavelength converters 132 to 147 can convert the wavelength of the input optical signal into the designated output wavelength. For example, the wavelength converters 132 to 135 convert the wavelengths of input arbitrary optical signals into wavelengths λ1, λ2, λ3, and λ4, respectively, and send them out.

As shown in FIG. 10, the optical space switch circuits 112 to 115 branch the optical signals input to the input ports 200 to 203 by branch links 208 to 211. The selectors 212 to 215 select one of the branched optical signals and output it to the output ports 204 to 207. This selector is a 2-input × 1-output unit selector whose connection mode is controlled by, for example, a 1-bit control signal.
It is realized by connecting in an e-shape (control signals are omitted for simplicity below).

In FIG. 9, the operation when converting the optical signal of wavelength λ1 multiplexed on the input line 100 into the optical signal of wavelength λ4 multiplexed on the output line 106 and transmitting it will be described (wavelength λ1 The transmission signal is superposed on the optical signal of 1. by a certain modulation method, and the data is also copied with the same polarity or the opposite polarity with the wavelength conversion to the wavelength λ4. Including data copy operation). The optical signal of the input line 100 is branched by the branch link 108 and connected to all the optical space switch circuits 112 to 115. In this connection example, the optical space switch circuit 114 corresponding to the destination output line 106.
Top input port (input port 200 in Figure 10)
Entered in. The optical space switch circuit 114 connects the input port 200 and the output port 207 in FIG. 10, selects the wavelength λ1 with the tuner 127, and selects the wavelength converter 1.
It is converted into wavelength λ4 by 43. That is, in the wavelength cross-connect circuit of FIG. 9, the wavelength converter 143 corresponding to the conversion destination wavelength λ4 of the destination output line 106, the tuner 127 connected thereto, and the wavelength λ1 (input wavelength) selected by the tuner 127 are Uniquely, the selectors 212 to 21 of the optical space switch circuit 114
The connection pattern of 5 is given and the connection route is determined. In FIG. 9, the principle is that the input optical signal is first distributed, and then the wavelength is converted. However, as an opposite configuration, the wavelength conversion may be performed first and then the output optical signal may be focused. . That is, in FIG.
An optical signal is input from the 107 side, and the route set in FIG. 9 is traced in reverse. A conventional example will be described with reference to FIGS. 11 and 12. FIG. 11 is a block diagram of another conventional cross-connect circuit. FIG. 12 is a block diagram of another conventional optical space switch circuit. Four wavelengths λ1 to λ4 are multiplexed on the input lines 300 to 303 and the output lines 304 to 307, respectively. The branch links 308 to 311 are input lines 300 to 3 respectively.
03 optical signals are distributed. Tuner 312-327
Selects a designated wave from the wavelength-multiplexed input optical signals. For example, the tuners 312 to 315 convert the wavelengths λ1, λ2, λ3, and λ4 of the input optical signal into the wavelengths on the destination output lines 304 to 307, respectively. Coupling links 348-351 are optical space switch circuits 344-34.
7 and the output lines 304 to 307 are optically coupled. Optical space switch circuits 344-34
7, the output signals of the wavelength converters 328 to 343 are input to the input ports 400 to 403 as shown in FIG. The multiplexers 408 to 411 route the wavelength-converted optical signals to the coupling links 412 to 415 corresponding to the destination output ports 404 to 407, respectively. The multiplexers 408 to 411 are realized, for example, by connecting unit multiplexers of 1 input × 2 output in a tree shape (each unit multiplexer is controlled by a 1-bit control signal, but for simplicity, the control signal is Is omitted). The coupling links 412 to 415 are multiplexers 40.
The optical signals addressed to the same output ports 404 to 407 of 8 to 411 are focused. In FIG. 11, for example, the input line 300-
An optical signal of wavelength λ1 of 303 is output by wavelength λ4 of output line 306.
The operation in the case of converting to and sending out will be described. Input line 3
The optical signals of 00 are wavelengths λ1 to λ at tuners 312 to 315.
4 and the respective wavelengths are converted into wavelength converters 328 to 3
It is input to 31. The optical signal of wavelength λ1 is output from the tuner 312.
And is converted into a wavelength λ4 by the wavelength converter 328. The optical signal of wavelength λ4 output from the wavelength converter 328 is input to the top input port (the input port 400 of FIG. 12) of the optical space switch circuit 344, and the multiplexer 408 outputs the output corresponding to the destination output line 306. It is routed to the port 406 and finally sent out from the output line 306. Both the configurations of FIGS. 9 and 10 are configurations in which the circuits are modularized corresponding to the input / output lines. Therefore, by adding or deleting unit modules according to the increase / decrease in the number of lines, it is possible to efficiently and easily add more units. It is possible.

[0005]

However, in both cases, the optical signal of one input line or output line is (number of lines).
× (wavelength multiplex) The optical signal level drops due to branching or coupling of the internal links, and multiple stages of optical amplifiers are required for each wavelength signal to compensate for this, increasing the circuit scale and power consumption. However, there is a problem that the cost increases. Therefore, the conventional configurations of FIGS. 9 to 12 are limited in application to a relatively small-scale system.

Now, a conventional example in which the above-mentioned drawbacks are further improved and which can be applied to a large-scale system will be described with reference to FIG. FIG. 13 is a block diagram of another conventional example. Input lines 500-502 and output lines 503-5
In 05, three wavelengths λ1 to λ3 are multiplexed. Unit wavelength switch circuits 506 to 508, 509 to 5
11, 512 to 514 are the first stage, the second stage, and the third stage, respectively.
It is located in the tier. In the first-stage unit wavelength switch circuit 506, the input wavelength-multiplexed signal is demultiplexed by the wavelength demultiplexing / demultiplexing circuit 515 into wavelengths λ1 to λ3, which are sent to the wavelength converters 516 to 518, respectively, and converted into designated wavelengths. Then, they are multiplexed and demultiplexed into wavelengths λ1 to λ3 by a wavelength demultiplexing circuit 519. As a result, each input wavelength is converted into a wavelength corresponding to the output of the connected unit wavelength switch circuit 506, and is routed to the corresponding output. In the second-stage unit wavelength switch circuit 509,
The input signals from the first stage are wavelength converters 520-5, respectively.
After being sent to the optical fiber 22, the wavelength is demultiplexed to a designated wavelength, then multiplexed, and demultiplexed into wavelengths λ1 to λ3 by a wavelength demultiplexing circuit 523. As a result, each input signal of the unit wavelength switch circuit 509 is converted into a wavelength corresponding to the output of the connected unit wavelength switch circuit 509, and is routed to the corresponding output. Third stage unit wavelength switch circuit 51
In No. 2, the input signals from the second stage are sent to the wavelength converters 524 to 526, respectively, after being converted to the designated wavelength, multiplexed, and sent from the output line 503. The respective stages are connected by optical links 527 to 528, but as shown in FIG. 13, the unit switch circuits 50 of the second and third stages are connected.
Optical signals of different wavelengths are input to the inputs 9 to 514.

From the above description, the unit wavelength switch circuits 506, 509, 512 are equivalent in view of the fact that the input and output wavelengths correspond to the input and output terminals of each unit wavelength switch circuit 506, 509, 512. 13 is equivalent to a 3-input × 3-output space switch, and the configuration of FIG. 13 corresponds to a generally well-known 3-stage switch circuit as a whole, and connects arbitrary input / output ports (in this case, between wavelengths). Connection) is possible. In this configuration, the optical signal loss corresponding to the number of wavelength multiplexes occurs at each stage due to the multiplexing, but the overall loss of the optical signal at the multiplexing part is when the number of wavelength multiplexes is larger than the number of input lines. Is less than in FIGS. 9 and 10. However, the number of wavelength converters in the configuration of FIG.
The number of input / output lines is greater than that of 0, and the unit wavelength switch circuits 509 to 511 in the second stage correspond to the maximum number of input / output lines from the beginning even when the number of input / output lines is one. There is a problem that the number of units is required and the expansion cannot be realized efficiently.

The present invention has been made against such a background, and the loss of an optical signal due to the branching and multiplexing of the optical signal is small, the number of wavelength converters required is small, and the expandability is excellent. It is an object of the present invention to provide a wavelength cross connect circuit applicable to a large scale to a large scale system.

[0009]

The first aspect of the present invention is to:
A wavelength cross-connect circuit equipped with multiple input lines to which optical signals arrive and means for converting the optical signals to the same wavelength or to other wavelengths according to the destination information and connecting to the output line for each destination. is there.

Here, a feature of the present invention is that the connecting means is composed of a combination of modules in which an output route pattern of an incoming optical signal is fixedly set according to its wavelength. Where it is.

It is desirable that the path setting pattern of the module be one for each of the input side and the output side for many types of wavelength cross-connect circuits (FIG. 1).

The route setting pattern of the module may be one type for many types of wavelength cross-connect circuits (FIG. 7).

There is one input side terminal and n output side terminals.
Module for input side which respectively distributes optical signals of wavelengths λ _{1 to} λn arriving at the input side terminal to the output side terminal, and n input side modules and 1 output side terminal.
Wavelengths λ ₁ arriving at the input side terminals
An output side module for multiplexing an optical signal of λn to its output side terminal, an output side terminal of the input side module and an input side terminal of the input side module are connected by a plurality of optical paths. Is desirable (Fig. 1).

A second aspect of the present invention is to provide a main wiring board (MD) of a switching device constituted by this wavelength cross connect circuit.
F) (Fig. 8).

[0015]

By providing the wavelength routing circuit after the wavelength converter, wavelength multiplexing can be realized without multiplexing loss, and a decrease in optical signal level in the wavelength cross connect process can be reduced.

Further, the input modules including the wavelength routing circuits are installed in parallel, and the optical signals from the output links at the same positions of those wavelength routing circuits are multiplexed,
By routing to the corresponding output line, the optical signal addressed to the output line can be wavelength-multiplexed and transmitted from each input module.

By combining an input module accommodating an input line and an output module accommodating an output line, wavelength cross-connect circuits of various scales can be constructed. Alternatively, the input / output modules can be distributed and configured and distributed.

In the conventional system, each link accommodates only one wavelength in a three-stage configuration, but since it can be configured in a two-stage configuration, the circuit expandability is improved and the circuit scale is reduced by reducing the number of stages ( The number of wavelength converters, the number of wirings) and the loss of optical signals are reduced.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram of a first embodiment device of the present invention. FIG. 2 is a block diagram of the input module of the first embodiment of the present invention.

According to the present invention, a plurality of input lines 700 to 702 to which an optical signal arrives, and the optical signal is converted to the same wavelength or another wavelength according to the destination information and connected to the output line for each destination. Input module 706 as means
.About.708 and output modules 709 to 711. FIG.

Here, the feature of the present invention lies in that the input modules 706 to 708 and the output module 70.
9 to 711 are formed by a combination of modules in which an output route pattern is fixedly set for an incoming optical signal according to its wavelength.

In the input module shown in FIG. 2A, the input port 600 and the output port 608 are each multiplexed with three wavelengths λ1 to λ3. Tuner 6
01 to 603 select an arbitrary wavelength from the optical signals of wavelengths λ1 to λ3. The wavelength converters 604 to 606 convert to fixed output wavelengths different from each other. The wavelength-converted optical signal is routed by the wavelength routing circuit 607.

Three-input, three-output wavelength routing circuit 607
Is shown in FIG. For example, from input port 2 wavelength λ
When the optical signals of 1, λ2 and λ3 are input, they are routed to the output ports 3, 1 and 2, respectively. On the contrary, when the optical signals of wavelengths λ1, λ2, and λ3 are input from the output port 1, they are routed to the input ports 1, 2, and 3, respectively, and operate in principle as a lossless wavelength demultiplexing circuit. A routing pattern represented by a matrix is shown in FIG. The pattern is such that the same wavelength does not appear in duplicate in the same column or row. The wavelength routing circuit 607 has three inputs and one output. In FIG. 2A, the input wavelength λ
A case in which the optical signal of No. 1 is converted into the optical signal of wavelength λ3 and is output will be described. When the input optical signal of wavelength λ1 is selected by the tuner 603, this optical signal is output by the wavelength converter 60.
The wavelength is converted into the wavelength λ3 at 6 and is output to the output port 608 at the wavelength routing circuit 607.

The input module shown in FIG.
It is equivalent to the input module shown in (b). Tuner 6
01 to 603 can be replaced by the wavelength routing circuit 609 and the optical space switching circuit 610. The wavelength routing circuit 609 separates the wavelengths λ1 to λ3 in a fixed order. The input module shown in FIG. 2B also has no loss due to branching or multiplexing. Wavelength routing circuit 607,
As a concrete circuit configuration method of 609 and 611, a method of combining a tuner circuit, a method of combining a wavelength multiplexing circuit and a wavelength demultiplexing circuit, and a method of configuring by using a circuit grating have been widely known from the past, and details thereof Since such a configuration is not a direct object of the present invention, description thereof will be omitted. However, among these realization methods, for example, an array waveguide grating tuner in which a large number of glass waveguides are arranged in an array on a silicon substrate can be integrated and is excellent in loss and crosstalk. It has characteristics. Further, in the wavelength cross-connect circuit of the present invention, it is necessary to connect the circuit modules with an optical fiber, and the array waveguide grating tuner is optimal because the glass waveguide and the fiber can be easily connected and the connection loss is small. is there.

Returning to FIG. 1, each of the input lines 700 to 702 and the output lines 703 to 705 has three wavelengths λ1.
.Lamda.3 are multiplexed. Input modules 706-70
8 assigns each wavelength of the input lines 700 to 702. The output modules 709 to 711 are the input modules 706.
~ 708 output wavelengths from the output lines 703 to 705
Converted to the corresponding wavelength and output. The optical link 712 is
Input modules 706-708 and output module 7
09 to 711 are connected in a mesh shape. Each input module 706-708 and each output module 709-71
The input modules 706 have the same structure.
˜708 are tuners 713 to 715 and a wavelength converter 71.
6 to 718, the wavelength routing circuit 719, the output modules 709 to 711, the coupling link 720 for multiplexing the optical signal input from the optical link 712 connected to the input modules 706 to 708, the wavelength routing circuit 721, and the fixed It is composed of wavelength converters 722 to 724 for converting an input wavelength into a specified output wavelength and a coupling link 725 for multiplexing output wavelengths.

As an example of the connection, the operation when the optical signal of wavelength λ2 on the input line 700 is converted into the optical signal of wavelength λ3 on the output line 704 and transmitted will be described. Input line 700
In order to route the input optical signal of wavelength λ2 from the input module 706 in which the input signal is stored to the output module 710 in which the output line 704 of the destination is stored, one of the wavelength converters 716 to 718 is selected. , Fig. 2
It is necessary to set the wavelength to be routed to the output port 2 of the wavelength routing circuit 719 according to the routing pattern of (d). In this wavelength selection, the destination output module 710 is the other input module 707.
And 708 are also connected so that other input lines 701, 7 routed to the output module 710.
The 02 wavelength needs to be selected from wavelengths other than those already assigned. Because each output module 709-
This is because in 711, the wavelengths sent from all the input modules 706 to 708 are once combined and then demultiplexed for each wavelength, so that the same wavelength cannot be used in duplicate. From the above operation principle, it is understood that the circuit configuration of FIG. 1 is logically equivalent to the three-stage switch circuit as in FIG. 13 shown in the conventional example. That is, this configuration example corresponds to the presence of three groups having three different wavelengths (corresponding to the second-stage unit wavelength switch circuits 509 to 511 in FIG. 13). If the output wavelength is not specified, the wavelength converters 722 to 724 in the output modules 709 to 711 can be omitted (the same discussion holds in the following embodiments). Although FIG. 1 shows an example in which the number of wavelengths multiplexed in the external input / output line is equal to the number of wavelengths multiplexed in the internal optical link 712, a configuration in which the numbers of wavelengths multiplexed in both are not generally possible is possible. However, when the number of internal wavelengths is small, the specified input / output line may not be connected, and there is a trade-off relationship between the circuit scale and the connection characteristic. Comparing the configuration of the first embodiment of the present invention shown in FIG. 1 with the configuration shown in FIG. 9 and FIG. 11 as a conventional example, loss due to distribution or multiplexing of optical signals is small (in the conventional configuration, the optical signal level is low). Is 1 /
[The number of wavelengths × the number of modules] is reduced, whereas in the configuration of the first embodiment of the present invention, it is reduced to 1 / [the number of modules]). Further, as compared with the configuration of the conventional example shown in FIG. 13, in the configuration of the first embodiment of the present invention shown in FIG. 1, the overall circuit scale increases in proportion to the number of input / output lines, and the expansion is easy. is there. In addition, the number of wavelength converters is small (a tuner is required in place of some wavelength converters, but the tuner is generally more cost-effective than the wavelength converter), which is economical.

The point of the first embodiment of the present invention shown in FIG. 1 is that the wavelength routing circuit 719 is installed in parallel and the input is connected to wavelength converters 716 to 718 as wavelength converting means. The output link is the link 72
They are connected by 0, and other parts can have various configurations depending on the device used.
In the input modules 706 to 708 in FIG. 1,
The tuners 713 to 715 can also be realized by the configuration shown in FIG.

Further, the input modules 706 to 708 can be realized by other configurations. Another configuration will be described with reference to FIG. FIG. 3 is a diagram showing another configuration of the input modules 706 to 708. The wavelength routing circuit 800 is connected to the input line 700 as a wavelength demultiplexing circuit. The opto-electric converters 801-803 convert optical signals into electrical signals,
The received wavelength-multiplexed signal is separated into each wavelength and then converted into an electrical signal (the transmission data superimposed on each wavelength is demodulated). The transmission data thus converted into the electric signal is connected to the corresponding wavelength tunable lasers 805 to 807 in the electric signal switch circuit 804, and the output light thereof is modulated by the electric transmission data signal. Tunable laser 805
The optical signals output from ˜807 are wavelength converters 71 in FIG.
6 to 718, the input module shown in FIG. 3 is replaced by the input modules 706 to 7 shown in FIG.
08 can be replaced. The configuration shown in FIG. 3 is a configuration in which a part of the optical space switch circuit and the wavelength converter is configured by an electric circuit, and can be easily realized by using a commercially available device in place of the wavelength conversion device at the research stage.

The output modules 709 to 711 of FIG. 1 use the wavelength routing circuit shown in FIG. 2C as a wavelength demultiplexing circuit, and are characterized by a small number of parts. Other configurations are generally possible. Another configuration will be described with reference to FIG. FIG. 4 shows the output module 709-
It is a figure which shows the other structure of 711. The optical link 712, the output line 703, and the wavelength routing circuit 7 shown in FIG.
Reference numeral 21 is provided as a wavelength demultiplexing circuit. The wavelength-multiplexed signal received is separated into each wavelength by the wavelength routing circuit 721, then converted into an electric signal (demodulation of transmission data superimposed on each wavelength), and the wavelength tunable laser 90.
4 to 906, the output light of which is modulated by electric transmission data. The wavelength tunable lasers 904 to 906 are shown in FIG.
As shown in (b), a switch circuit 907 for electric signals
The wavelength tunable lasers 908 to 910 can be replaced with lasers having fixed wavelengths having different oscillation wavelengths. Figure 4
4C is a configuration in which the switch circuit 907 of FIG. 4B is realized by tuners 912 to 914, and the star coupler 911 has wavelengths λ1 to λ input from the optical link 712.
All three outputs are distributed at the same time that the three wavelengths are combined.
For example, an operation of converting an optical signal of wavelength λ3 input from the optical link 712 into an optical signal of wavelength λ2 of the output line 703 and transmitting the optical signal will be described. The input optical signal of wavelength λ3 is distributed to all tuners 912 to 914 by the star coupler 911 no matter which link of the optical link 712 arrives. Therefore, the tuner 913 connected to the tunable wavelength laser 909 for transmitting the converted output wavelength λ2 selects the optical signal of the wavelength λ3, converts it into an electric signal by the photoelectric converter 902, and outputs the variable wavelength with the output data signal. Laser 9
09 is modulated. Further, the optoelectric converters 901 to 903 and the variable wavelength lasers 908 to 910 can be replaced with the wavelength converters 722 to 724 shown in FIG. These configurations are similar to those in FIG. 3, and output modules 709 to 71 are provided.
A part of the wavelength converters 722 to 724 in No. 1 is realized by using an electric circuit, and has a feature that it can be easily realized by using a device which is currently on the market.

A second embodiment of the present invention will be described with reference to FIG. FIG. 5 is a block diagram of the apparatus of the second embodiment of the present invention. Input lines 1000 to 1002 and output line 100
Although three to three hundred three are three, respectively, a configuration example when the number of wavelength division multiplexing is increased to six wavelengths is shown. Input module 10
The optical links 1012 connect the output modules 06 to 1008 and the output modules 1009 to 1011. The inside of the input modules 1006 to 1008 is a tuner 1012.
-1017, wavelength converters 1018-1023, and wavelength routing circuits 1024, 1025. The output modules 1009 to 1011 include a wavelength routing circuit 1026 as a wavelength demultiplexing circuit and a wavelength converter 1027.
-1032. The configuration of the second embodiment of the present invention shown in FIG. 5 differs from the configuration of the first embodiment of the present invention shown in FIG. 1 in principle in that input modules 1006 to 1008.
The wavelength routing circuits 1024 and 1025 are divided into a plurality (two in FIG. 5). The plurality of wavelength routing circuits 1024 and 1025 have different wavelength operation regions, but have the same relative operation wavelength width. That is, when one large-scale wavelength routing circuit 719 is used as shown in FIG. 1, and the wavelength interval is δ, the wavelength band of wavelengths λ0 to λ0 + 6δ is required in the configuration principle of FIG. On the other hand, in the example of FIG. 5, since the wavelength region is divided into two, λ0 to λ0 + 3δ and λ0 + 3δ to λ.
This can be realized by the wavelength routing circuits 1024 and 1025 whose relative wavelength ranges of 0 + 6δ are 3δ. As described above, although the types of the wavelength routing circuits 1024 and 1025 increase, the advantage that the input modules 1006 to 1008 can be easily configured by using the small-sized wavelength routing circuits 1024 and 1025 even when the wavelength multiplexing number of the input / output ports is large. There is.

A third embodiment of the present invention will be described with reference to FIG. FIG. 6 is a block diagram of the apparatus of the third embodiment of the present invention. The wavelength routing circuits 1104 and 1105 as the wavelength separation circuits of the output modules 1100 to 1102 are divided corresponding to the division of the wavelength routing circuits 1106 and 1107 of the input modules 1006 to 1008. In FIG. 6, input modules 1006-1008
Has the same configuration as the second embodiment of the present invention shown in FIG.
The output modules 1100 to 1102 have a new configuration. The input modules 1006 to 1008 and the output modules 1100 to 1102 are connected by an optical link 1103. The wavelength routing circuits 1104 and 1105 as wavelength demultiplexing circuits are divided into two. Wavelength routing circuit 110 of input modules 1006-1008
6 and 1107 are applicable to the second embodiment of the present invention shown in FIG. 5 as they are, but FIG. 6 shows a case where two identical wavelength routing circuits 1106 and 1107 are used. In FIG. 6, an optical link 11 for connecting input / output modules
This is a configuration in which a plurality of 03s are installed and the same wavelength is repeatedly used between them, thereby reducing the number of wavelengths required internally. Thus, in the third embodiment of the present invention,
Although the number of optical links increases, the wavelength routing circuit 11
06 and 1107 and the wavelength routing circuits 1104 and 1105 as the wavelength demultiplexing circuits can reduce the operating wavelength width and the number of ports. Small-scale wavelength routing circuit 1 even when the number of wavelength division multiplexing of input / output ports is large
There is an advantage that it can be easily configured using 106, 1107, 1104, and 1105. The configurations of the input / output module shown in FIGS. 3 and 4 can be applied to the configurations of FIGS. 5 and 6.

Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 7 is a block diagram of a fourth embodiment device of the present invention. The first to third embodiments of the present invention were designed under the condition that the wavelength cross-connect circuits are centrally installed inside the node. On the other hand, it is possible to disperse the wavelength cross-connect circuits in the network. The transmission modules 1206-1208 have input ports 1200-1202, respectively, and the reception modules 12
09-1211 are output ports 1203-120, respectively.
5 and is housed in the remote node. Hub node (h
ub node) 1212 is connected to these remote nodes in a star pattern. This connection is optical fiber cable 1228
~ 1233. The fourth embodiment of the present invention is
This corresponds to a distributed arrangement of the configuration of the first embodiment of the present invention shown in FIG. 1. For example, the input port 1200 of FIG. 7 corresponds to the input line 700 of FIG. The transmission module 1206 includes a wavelength multiplexing circuit for the optical input signal. This wavelength multiplexing circuit can be configured by a wavelength routing circuit. Figure 1
The wiring between the tuners 713 to 715 of the input module 706 and the wavelength converters 716 to 718 corresponds to the optical fiber 1228 in which the wavelength is multiplexed. The hub node 1212 is a wavelength routing circuit 1213 to 1215 and a wavelength converter 1216 to 12 as a wavelength demultiplexing circuit for demultiplexing the signals wavelength-division multiplexed on the optical fiber cables 1228 to 1230.
24 and wavelength routing circuits 1225-1227.
That is, in the configuration of FIG.
8 corresponds to the wavelength converters 1216 to 1224, the wavelength routing circuit 719 corresponds to the wavelength routing circuit 1225, and the optical link after the output of each wavelength routing circuit is multiplexed by the coupling link 720 is the optical fiber cable 1231.
Equivalent to. The receiving module 1209 includes the wavelength routing circuit 721 as the wavelength demultiplexing circuit shown in FIG. As described above, it is understood that the configuration is equivalent to the configuration of FIG. 1 except that the portions of the optical fiber cables 1228 to 1233 of the configuration of FIG. 7 are wavelength-multiplexed. Therefore, the control method of the connection is the same as that in FIG. The configuration of FIG. 7 has a hub node 1212 and remote nodes 1206 to 121.
Since the wavelength cross-connect function is distributed in 1, the configuration of the hub node 1212 is simplified. It should be noted that the wavelength cross-connect of the present invention is such that the drop of the optical signal level due to the branching or multiplexing of the optical signals is small, and the same module can be added to easily expand from a small-scale system to a large-scale system. The characteristics of the above are also retained in the fourth embodiment of the present invention shown in FIG. FIG. 7 shows a configuration example corresponding to the configuration of FIG. 1, but similarly, a distributed configuration corresponding to the configurations of FIGS. 3 to 6 can be easily derived. As described above, the distributed arrangement as shown in FIG. 7 makes it possible to economically construct a relatively small-scale network. As described above, the wavelength cross-connect circuit of the present invention can support both the centralized arrangement and the distributed arrangement. Therefore, the degree of freedom in network design is increased.

Next, an application example of the wavelength cross connect circuit will be described with reference to FIG. FIG. 8 is a diagram showing an application example of the wavelength cross connect circuit. The wavelength cross-connect circuits of the first to fourth embodiments of the present invention are the main wiring board MD of an optical communication line.
Suitable for use in F. The main distribution board MDF connects a plurality of input lines to a predetermined output line, and does not perform frequent switching connection like a switch after the connection setting is first made, but the input The connection setting is changed with the change of the line or the movement of the installation place of the communication terminal device. Since the scale thereof increases and decreases depending on the number of communication terminal devices and the number of communication lines, and the installation place also varies, it is useful that the degree of freedom in network design in the present invention is large.

[0034]

As described above, according to the present invention, the loss of optical signals due to the branching and multiplexing of optical signals is small, the number of wavelength converters required is small, the expandability is excellent, and the scale is small to large. A wavelength cross connect circuit applicable to a large scale system can be realized. Furthermore, it is possible to freely select a configuration in which the functions are distributed or centralized. Therefore, the degree of freedom in network design is increased.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of an apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram of an input module according to the first embodiment of the present invention.

FIG. 3 is a diagram showing another configuration of the input module.

FIG. 4 is a diagram showing another configuration of the output module.

FIG. 5 is a block configuration diagram of a second embodiment device of the present invention.

FIG. 6 is a block configuration diagram of a device according to a third embodiment of the present invention.

FIG. 7 is a block configuration diagram of a fourth embodiment device of the present invention.

FIG. 8 is a diagram showing an application example of a wavelength cross connect circuit.

FIG. 9 is a block diagram of a conventional wavelength cross connect circuit.

FIG. 10 is a block configuration diagram of a conventional optical space switch circuit.

FIG. 11 is a block configuration diagram of another conventional cross-connect circuit.

FIG. 12 is a block configuration diagram of another conventional optical space switch circuit.

FIG. 13 is a block diagram of another conventional example.

[Explanation of symbols]

100-103, 300-303, 500-502, 7
00-702, 1000-1002 Input line 104-107, 304-307, 503-505, 7
03-705, 1003-1005 Output line 108-111, 208-211, 308-311 Branch link 112-115 Optical space switch circuit 116-131, 312-327, 601-603, 7
13-715, 912-914, 1012-1017
Tuner 132-147, 328-343, 516-518, 5
20-522, 524-526, 604-606, 71
6-718, 722-724, 1018-1023, 1
027-1032, 1216-1224 Wavelength converter 200-203, 400-403, 600, 1200
1202 input ports 204 to 207, 404 to 407, 608, 1203 to
1205 output ports 212-215, 408-411 selectors 408-411 multiplexers 610, 344-347 optical space switch circuits 506-514 unit wavelength switch circuits 515, 519, 523 wavelength demultiplexing circuits 527, 528, 712, 1012, 1103 optical Links 607, 609, 611, 719, 721, 800, 1
024, 1025, 1026, 1104-1107, 1
213-1215, 1225-1227 Wavelength routing circuits 706-708, 1006-1008, 1100-11
02 Input module 709-711, 1009-1011 Output module 720, 725, 348-351, 412-415 Coupling link 801-803, 901-903 Photoelectric converter 804, 907 Switch circuit 805-807, 904-906, 908 ˜910 Wavelength tunable laser 911 Star coupler 1206 to 1208 Transmission module 1209 to 1211 Reception module 1212 Hub node 1228 to 1233 Optical fiber cable MDF Main wiring board

Claims (5)

[Claims] 1. A plurality of input lines to which an optical signal arrives, and means for converting the optical signal to the same wavelength or to another wavelength according to the destination information and connecting to the output line for each destination. In the wavelength cross-connect circuit, the connecting means is constituted by a combination of modules in which an output optical path pattern of the incoming optical signal is fixedly set according to the wavelength of the incoming optical signal. . 2. The route setting pattern of the module is:
The wavelength cross-connect circuit according to claim 1, wherein each of the plurality of types of wavelength cross-connect circuits is one for the input side and one for the output side. 3. The route setting pattern of the module is
The wavelength cross connect circuit according to claim 1, wherein one type is provided for many types of wavelength cross connect circuits. 4. A main wiring board (MD) of a switching device, which is constituted by the wavelength cross-connect circuit according to claim 1 or 2.
F). 5. The number of input side terminals is one, the number of output side terminals is n, and the wavelengths λ _{1 to} λn that arrive at the input side terminals.
Of the input side module which distributes the optical signal of each to the output side terminal, and the number of the input side terminals is n and the number of the output side terminals is one, and the wavelengths λ _{1 to} λn respectively arrive at the input side terminals. An output side module for multiplexing an optical signal to its output side terminal, an output side terminal of the input side module and an input side terminal of the input side module are connected by a plurality of optical paths, Wavelength cross connect circuit.