JPH06121356A - Wavelegth division type optical channel - Google Patents

Abstract

PURPOSE:To obtain the inexpensive wavelength division type optical channel in which number of times of wavelength conversion is one, number of required wavelength conversion circuits is decreased and an output wavelength of the wavelength conversion circuits is fixed. CONSTITUTION:An optical signal 30-1 inputted through M-wavelength division multiplexing is distributed (32-1) while plural wavelengths are multiplexed for each rotting path, the optical signals distributed from incoming optical highways are made confluent to apply multiplexing (33-1) to M-sets of wavelengths. Then the multiplexed M-wavelengths are distributed to M-sets of wavelength conversion circuits 37 converting the multiplexed wavelength into a desired output wavelength and the output M-wavelengths subject to wavelength conversion are distributed by selecting any of the outgoing optical highways 31-1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wavelength division type optical communication path in an optical switching system. The optical communication path system that forms the basis of the optical switching system includes a space division type, a time division type, a wavelength division type, and the like.
That is, the present invention relates to a wavelength division type optical communication path in which the number of usable wavelengths is theoretically infinite due to the high frequency property of light.

[0002]

2. Description of the Related Art FIG. 10 is a circuit diagram showing a configuration example of a wavelength division type optical communication path which has been conventionally proposed. This wavelength division type optical communication path is called a λ ³ switch. (Reference:
S.Suzuki and K.Nagashima "Optical Broadband Commun
ications Network Architecture Utilizing Wavelength
-Division Switching Technology "Proc. Topical Meet
ing on Photonic Switching, ThA-2, 1987)

In FIG. 10, 10-1 to 10-N are input optical highways, 11-1 to 11-N are output optical highways, and 12-11 to 12-1N and 12-, respectively.
21 to 12-2N and 12-31 to 12-3N are demultiplexers DEMUX and 13-11 to 13-1 respectively.
N, 13-21 to 13-2N, 13-31 to 13-3N
Are multiplexers MUX, 14-1 to 14-3, respectively.
Are variable wavelength output wavelength conversion circuits.

Referring to FIG. Each of the N incoming lines (input optical highways) 10-1 to 10-N has a wavelength λ.
Optical signals of M waves of _{1 to} λ _M are wavelength division multiplexed. Each optical signal is a demultiplexer DEMUX12-1.
In each of 1 to 12-1N, wavelength conversion is performed by the wavelength conversion circuit 14-1 so that the demultiplexers DEMUX 12-21 to 12-2N perform path selection in accordance with a routing path that is separated for each wavelength. After that, the multiplexers MUX 13-11 to 1
It is multiplexed again at 3-1N.

The multiplexed optical signals are similarly demultiplexers DEMUX 12-21 to 12-2N, wavelength conversion circuit 14-2, multiplexers MUX 13-21 to 13.
-2N, demultiplexer DEMUX12-31 to 12
-3N, wavelength conversion circuit 14-3, multiplexer MUX
13-31 to 13-3N, the desired outgoing line 11-1 to
Reach 11-N.

An example of the exchange operation will be described here. It is assumed that a certain signal having a wavelength λ ₁ from the incoming line (input optical highway) 10-1 is exchanged with the outgoing line (output optical highway) 11-1 and goes out. Next, if it is desired that another signal having the wavelength λ ₁ from the incoming line 10-2 is also exchanged to the same outgoing line 11-1 and goes out, both signals are separate signals, Since the wavelengths are the same, the lines 11-1 are mixed with each other, which is inconvenient. Therefore, in such a case, the wavelengths of either one of the signals are changed on the way to prevent them from being mixed.

First, the demultiplexer DEMUX 12-11 once demultiplexes the multiplexed signal coming in from the incoming line 10-1 for each wavelength. Here, the wavelength conversion circuit 14-1 performs the wavelength conversion. If, for example, λ ₁ is converted into λ ₂ , then 13-21 passes and 12-21 separates λ _2. You can go to -22. Further When the lambda ₁ at a wavelength converter 14-1 was converted into lambda _M, since it is separated as a lambda _M then through 13-11 in 12-21, it is possible to go to 13-2N.

Similarly, when wavelength conversion is performed by the wavelength conversion circuit 14-2, the destination to be subsequently selected can be selected from 13-31 to 13-3N depending on the wavelength to be converted. The wavelength conversion circuit 14-3 performs wavelength conversion so that signal channels having the same wavelength do not enter the same multiplexer MUX in the next stage. As described above, FIG.
In the conventional wavelength division type optical communication path shown in (3), wavelength conversion is required three times to perform the switching operation, and it is called a λ ³ switch.

In FIG. 11, (a) is a multiplexer MUX13-11 and a demultiplexer D shown in FIG.
It is the figure which illustrated the combination of EMUX12-21 again, but the function equivalent to this can be implement | achieved by the coupler 21 and the filter 22 as shown in (b). That is,
The coupler 21 multiplexes and splits each optical signal, and the filter 22 separates each optical signal.

The wavelength conversion circuit 14-shown in FIG.
Each of 1, 14-2, and 14-3 changes the wavelength to be converted and output each time the switching routing path is changed, and therefore it is necessary to use a wavelength conversion circuit that outputs a variable wavelength.

[0011]

In the conventional wavelength division type optical communication path described above, it is necessary to perform wavelength conversion three times as described above. In the configuration of FIG. 10, N × M × 3 wavelength conversions are performed. Circuit is required. Further, the output wavelength of the wavelength conversion circuit needs to be changed every time the routing path of the input optical signal is changed. As a result, the wavelength division type optical communication path is inevitably expensive.

An object of the present invention is to set the number of wavelength conversion circuits to one and the number of wavelength conversion circuits to N in the configuration shown in FIG.
(EN) Provided is a wavelength division type optical communication path in which the output wavelength of a wavelength conversion circuit can be reduced to × M and the output wavelength can be realized even at a fixed wavelength so that the cost can be reduced.

[0013]

According to the present invention, on N input optical highways that have been multiplexed by M wavelength division multiplexing, the optical signals on which the respective wavelengths are carried as signal channels are arbitrarily exchanged, and N optical signals are exchanged. In the wavelength division type optical communication path that outputs on the output optical highway of the book, the optical signal input by wavelength division multiplexing is distributed while multiple wavelengths are multiplexed for each routing path, and the light distributed from each input optical highway The signals are merged to multiplex M wavelengths, and the multiplexed M wavelengths are distributed to M wavelength conversion circuits that convert to desired output wavelengths, and the M wavelengths of the wavelength-converted outputs are selected as the output optical highway. I decided to distribute it.

[0014]

According to the present invention, the number of wavelength conversion circuits is reduced to N × M and the output wavelength of the wavelength conversion circuit is set to a fixed wavelength by setting the routing path by means not using the wavelength conversion circuit. A wavelength division type optical communication path is realized at low cost.

[0015]

1 and 2 are block diagrams showing a first embodiment of the present invention when they are connected to each other at a position where a broken line is drawn. In these figures, 30-1 to 30
-4 is an input optical highway, 32-1 to 32-4
Are distributors 33-1 to 33-4, 34-1 to 3 respectively
4-4 are merging / dividing devices, 35-1 to 35-4 are merging devices, 36-1 and 36-2 are plural wavelength selection filters, 37 is a wavelength converter, and 31-1 to 31-31.
4 is an output light highway, respectively.

In this embodiment, the number of input / output optical highways N =
4, the case of the number of wavelength division multiplexing M = 6 will be described, but it is of course possible to use any number of N and M. 1 and 2, the four input optical highways 30-1 to 30-1
Optical signals of 6 wavelengths λ _{1 to} λ ₆ are multiplexed in 30-4.

The optical signal input from the input optical highway is distributed by the one-to-four optical distributors 32-1 to 32-4 installed corresponding to the input highway and input to the plural wavelength selection filter 36-1. . Each of the plural wavelength selection filters transmits only one or a plurality of specific wavelengths from λ _{1 to} λ ₆ , and its output is 1 for each input highway.
The outputs are input to the 4 to 6 merge distributors 33-1 to 33-4.

4 to 6 optical merging / distributing devices 33-1 to 33-4
Is connected to a fixed wavelength output wavelength converter 37 that performs wavelength conversion to extract an optical signal of an arbitrary wavelength from the multiplexed 6 wavelengths (even if wavelength conversion is performed, The signal itself does not change).

The outputs of the respective wavelength converters are distributed by the 6 to 4 optical merging / distributing devices 34-1 to 34-4 and input to the plural wavelength selecting filter 36-2. The output of each of the plural wavelength selection filters 36-2 is the output optical highways 31-1 to 34-34.
The optical signals are connected to 4-to-1 optical multiplexers 35-1 to 354 installed corresponding to 4 and output optical highways 31-1 to 31-31.
4 is output.

FIG. 3 is a block diagram showing a structural example of the multiple wavelength selection filter 36-1 used in the embodiments shown in FIGS. The multiple wavelength selection filter shown in FIG.
Wavelengths λ _{1 to} λ ₆ input to the filter 44 through the incoming line 41
Of optical signals of different wavelengths (λ ₁ , λ ₃ , λ _{6 in} the example shown in the figure) from the optical signals different from each other are output to the output line 42, and the operation of blocking the optical signals of other wavelengths is performed. To do.

As such a filter, there is a document: N. Fu.
jimoto, et al. "Photonic Cross-connect Node Archit
ecture Utilizing Novel Multiwavelength Selective F
ilters "Proc. ECOC'90 (1990) gives a concrete example.

FIG. 4 is a block diagram showing an example of the construction of the fixed wavelength output wavelength converter 37 used in the embodiments shown in FIGS. The wavelength converter shown in FIG. 4 extracts one wavelength (λ _{3 in} the example in the figure) designated by the controller 53 from the optical signal having different wavelengths λ _{1 to} λ ₆ inputted from the incoming line 51 by the filter 54. The wavelength conversion circuit 55 performs wavelength conversion (output wavelength λ ₁ in the illustrated example) and outputs the result to the output line 52.

As the wavelength conversion circuit 55, a method of using three-wave mixing or four-wave mixing of an organic or inorganic non-linear material, a method of using a bistable LD whose original signal is trigger light during intensity modulation, and a frequency are used. FM-I during modulation
A method of injecting signal light into a light source such as an LD after M conversion to change the carrier density in the light source to modulate the oscillation frequency, a method of extracting and amplifying a side band of modulated signal light, injection locking and Brillouin scattering As described above, there are a method of connecting a plurality of effects with small frequency shifts in multiple stages to obtain a large frequency change, a method of converting a light signal into an electric signal by an optical receiver and modulating an optical signal of a specific wavelength with the electric signal.

[0024] In the present embodiment will prepare six types of wavelength converter having an output wavelength lambda ₁ to [lambda] _6. next,
The operation as an optical communication path will be described with reference to FIGS.

The optical communication path is required to convert optical signals input from the input highway and having different wavelengths to the desired output highway and output the converted signals. Naturally, even when optical signals having different wavelengths input from the same input highway are output to different output highways with the same wavelength, it is necessary to be correctly routed.

In this embodiment, λ _{1 is set} on four highways.
Since ₆ wavelengths of ˜λ ₆ are multiplexed, there are four optical signals each having the same wavelength. Wavelength converter 37
It is obvious that the optical signals of the same wavelength are not input to the 6-to-4 optical merging / distributing devices 34-1 to 34-4 at the output of 4). The input optical signals to 33-4 do not have the same wavelength after (1) conversion.
(2) It is necessary to satisfy the two conditions that the wavelengths are not the same before conversion (such a combination always exists). The combinations are shown in Table 1 below, so that reference can be made to them.

[0027]

[Table 1]

A plurality of routing paths are set so that optical signals of the same wavelength are not input to the 4 to 6 optical multiplexer / distributor 33-1 to 33-4 and desired wavelength conversion is realized. It is realized by controlling the selection wavelength of the wavelength selection filter 36-1 and by controlling the selection wavelength of the multiple wavelength selection filter 36-2 so that the output highway is output to a desired output highway.

5 and 6 are block diagrams showing a second embodiment of the present invention when they are coupled to each other at a position where a broken line is drawn. In these figures, 60-11 to
Reference numerals 60-14, 60-21 to 60-24 denote wavelength separation circuits capable of wavelength separation in arbitrary wavelength combinations, 61-
1 to 61-4 are mergers, respectively.

In this embodiment, the optical signal input from the input optical highway is wavelength demultiplexing circuit 6 capable of wavelength demultiplexing with any combination of wavelengths installed corresponding to the input highway.
0-11 to 60-14 directly distributes the input optical signal according to the routing path of the input optical signal, and inputs it to the 4 to 6 merge distributors 33-1 to 33-4.

The outputs of the respective wavelength converters 37 are multiplexed by the 6-input combiners 61-1 to 61-4, and then the wavelength separation circuit 60- capable of wavelength separation by an arbitrary combination of wavelengths.
4 to 1 assigned to each route by 21-60-24
It is connected to the optical combiners 35-1 to 35-4. The other structure is the same as that of the first embodiment.

FIG. 7 is a block diagram showing a configuration example of the wavelength demultiplexing circuits 60-21 to 60-24 used in the embodiments shown in FIGS. This wavelength demultiplexing circuit is described in the literature: K.Aid
a et al. "Optical Protection Switchies for Trunk Tr
Ansmission Systems "Proc. ICC'88 (1988).

In FIG. 7, the optical signals of the wavelengths λ _{1 to} λ ₆ input from the incoming line 70 correspond to the respective oscillation frequencies of the six oscillators 73 set by the control device 74.
Transducer 72, acoustic / optical deflector (Acous
The advancing direction is controlled by the t-Optic Deflector) 71, and the light is separated into the outgoing lines 76-1 to 76-4 with an arbitrary wavelength combination through the light receiving guides 75-1 to 75-4. In this figure, (λ ₁ λ ₃ ), (λ ₂ λ ₅ ),
An example in which (λ ₄ ) and (λ ₆ ) are separated is shown.

FIG. 8 and FIG. 9 are block diagrams showing a third embodiment of the present invention when they are connected to each other at a position where a broken line is drawn. In these figures, 80-1 to 8-8
0-4 are demultiplexers DEMUX, 81-
11 to 81-14, 81-21 to 81-24 are space switches, and 82-1 and 82-2 are multiplexers MUX.

In the present embodiment shown in FIGS. 8 and 9, the optical signal input from the input optical highway is the demultiplexer DEMUX 80-1 installed corresponding to the input highway.
~ 80-4, separated by wavelength, 6 inputs (6x
4) Input to the output space switches 81-11 to 81-14.

The input optical signal is distributed by the space switch according to its routing path, then multiplexed by the multiplexer MUX 82-1 and input to the 4-to-6 merge / divider 33-1 to 33-4. In addition, the output of each wavelength converter 37 is distributed to each path by the 6-input (6 × 4) output spatial switches 81-21 to 81-24, and then multiplexed by the multiplexer MUX82-2 to be 4: 1. It is connected to the optical combiners 35-1 to 35-4. The other structure is the same as that of the first embodiment.

[0037]

As described above, according to the present invention, routing is possible with one wavelength conversion, and the required number of wavelength conversion circuits is (the number of input / output optical highways is N, the number of wavelength multiplexing is M). In this case, there is an advantage that a low cost wavelength division type optical communication path can be realized by N × M pieces and the output wavelength of the wavelength conversion circuit is fixed.

[Brief description of drawings]

FIG. 1 is a block diagram showing an upper half of a first embodiment of the present invention.

FIG. 2 is a block diagram showing a lower half of the first embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration example of a multiple wavelength selection filter 36-1.

FIG. 4 is a block diagram showing a configuration example of a wavelength converter 37 having a fixed wavelength output.

FIG. 5 is a block diagram showing an upper half of a second embodiment of the present invention.

FIG. 6 is a block diagram showing a lower half of a second embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration example of wavelength separation circuits 60-21 to 60-24.

FIG. 8 is a block diagram showing an upper half of a third embodiment of the present invention.

FIG. 9 is a block diagram showing a lower half of a third embodiment of the present invention.

FIG. 10 is a circuit diagram showing a configuration example of a conventionally proposed wavelength division type optical communication path.

FIG. 11 shows a combination of a multiplexer MUX13-11 and a demultiplexer DEMUX12-21 (a).
2B is a configuration diagram showing another circuit having a function equivalent to that in FIG.

[Explanation of symbols]

10-1 to 10-N, 30-1 to 30-4 ... Input optical highway, 11-1 to 11-N, 31-1 to 31-4 ... Output optical highway, 12-11 to 12-3N, 80- 1 to
80-4 ... Demultiplexer DEMUX, 13-11 to 13
-3N, 82-1 and 82-2 ... Multixer MUX, 14
-1 to 14-3 ... Variable wavelength output wavelength conversion circuit, 21 ... Coupler, 22 ... Fixed wavelength filter, 32-1 to 32-4 ...
Distributor, 33-1 to 33-4, 34-1 to 34-4 ... Merging / distributor, 35-1 to 35-4, 61-1 to 61-4
... merger, 36-1, 36-2, 44 ... multiple wavelength selection filter, 37 ... wavelength converter, 41, 51, 70 ... incoming line,
42, 52, 76-1 to 76-4 ... Outgoing line, 43, 53 ...
Selection wavelength control device, 54 ... Variable wavelength filter, 55 ... Fixed wavelength output wavelength conversion circuit, 60-11 to 60-24 ... Arbitrary wavelength combination wavelength separation circuit, 71 ... Acoustic / optical deflector, 72 ... Transducer, 73 ... Oscillator, 74 ... Oscillator control device, 75-1 to 75-4 ... Light receiving guide, 81
-11 to 81-24 ... Space switch

Claims (7)

[Claims] 1. An N-type optical highway configured by dividing light into M wavelengths, multiplexing each of the M wavelengths as a signal channel, and M wavelengths as an M channel, is used as an input highway. In a wavelength division type optical communication path in which signal channels are switched as desired on the highway and then output as N output highways (where M and N are natural numbers of 2 or more), N N optical signals that take in M optical signals of M wavelengths on the highway
Distributors (32-1 to 32-4) and a plurality of channels of an arbitrary combination of a plurality of wavelengths, which are connected to the N outputs of the respective N distributors, from an optical signal of M channels of M wavelengths. N × N multiple wavelength selection filters (36-1) for extracting and outputting optical signals and outputs of each of the multiple wavelength selection filters are selected one by one for each input highway, merged, and M-distributed. N N
Input M output merging / distributor (33-1 to 33-4) and M output of each of the N input M output merging / distributor, and arbitrarily specified from M channel optical signals having M wavelengths. N wavelength conversion circuits (37) for extracting a 1-channel signal consisting of 1 wavelength by wavelength conversion, and the M wavelengths connected to the M outputs of the N input M output merge distributors. N M-input N-output merging distributors (34-1 to 34-4) for merging output optical signals of the converting circuit and N-dividing for each output highway, and N of each M-input N-output merging distributor N × N multi-wavelength selection filters (36-2) connected to the output of the book and extracting and outputting multi-channel signals of arbitrary multi-wavelengths from M-channel optical signals of M wavelengths
A wavelength division type optical communication path comprising at least: 2. An N-type optical highway configured by dividing light into M wavelengths, multiplexing each of the M wavelengths as a signal channel, and M wavelengths as an M channel, and inputting the input highway. In a wavelength division type optical communication path in which signal channels are exchanged as desired on the highway and then output as N output highways (where M and N are natural numbers of 2 or more), N wavelength demultiplexing circuits (60-1) that take in M channel optical signals consisting of M wavelengths on the highway and separate them into N outputs by combining arbitrary wavelengths
1 to 60-14) and N outputs of each of the wavelength demultiplexing circuits are selected one by one for each input highway to be merged and M-divided into N N-input M-output merge distributors (33- 1-33-4) and M outputs of each of the N-input M-output merging / distributing devices, from M-channel optical signals of M wavelengths to 1-channel signal of arbitrary specific wavelength. Of N wavelength conversion circuits (37) for extracting the light by wavelength conversion, and the output optical signals of the M wavelength conversion circuits connected to the M outputs of the N input M output merging / distributing distributors. , N input M output merge distributors (34-1 to 34-4) for N distribution corresponding to each output highway, and M outputs connected to N outputs of each M input N output merge distributor. From the M-channel optical signal having the wavelength N × N number of multiple wavelength selective filter for outputting an extracted signals tunnel (36-2)
A wavelength division type optical communication path comprising at least: 3. N-number of optical highways configured by dividing light into M wavelengths, multiplexing each of the M wavelengths as a signal channel and M wavelengths as M channels, and inputting the input highways. In a wavelength division type optical communication path in which signal channels are switched as desired on the highway and then output as N output highways (where M and N are natural numbers of 2 or more), N N optical signals that take in M optical signals of M wavelengths on the highway
Distributors (32-1 to 32-4) and a plurality of channels of an arbitrary combination of a plurality of wavelengths, which are connected to the N outputs of the respective N distributors, from an optical signal of M channels of M wavelengths. N × N multiple wavelength selection filters (36-1) for extracting and outputting optical signals and outputs of each of the multiple wavelength selection filters are selected one by one for each input highway, merged, and M-distributed. N N
Input M output merging / distributor (33-1 to 33-4) and M output of each of the N input M output merging / distributor, and arbitrarily specified from M channel optical signals having M wavelengths. N wavelength conversion circuits (37) for extracting a 1-channel signal consisting of 1 wavelength by wavelength conversion, and the M wavelengths connected to the M outputs of the N input M output merge distributors. N M-input combiners (61-1 to 61-) that take in the output optical signals of the conversion circuit, combine them, and output them.
4) and N wavelengths which are the combined outputs from the M input combiners and take in the M-channel optical signal consisting of M wavelengths and separate and output them into N outputs at any combination of wavelengths. A wavelength division type optical communication path comprising at least separation circuits (60-21 to 60-24). 4. An optical highway, which is constituted by dividing light into M wavelengths, each wavelength being a signal channel, and multiplexing the M wavelengths as an M channel, is an input highway, and the input highway. In a wavelength division type optical communication path in which signal channels are exchanged as desired on the highway and then output as N output highways (where M and N are natural numbers of 2 or more), N wavelength demultiplexing circuits (60-1) that take in M channel optical signals consisting of M wavelengths on the highway and separate them into N outputs by combining arbitrary wavelengths
1 to 60-14) and N outputs of each of the wavelength demultiplexing circuits are selected one by one for each input highway to be merged and M-divided into N N-input M-output merge distributors (33- 1-33-4) and M outputs of each of the N-input M-output merging / distributing devices, from M-channel optical signals of M wavelengths to 1-channel signal of arbitrary specific wavelength. N wavelength conversion circuits (37) for extracting wavelengths by wavelength conversion, and taking in and combining output optical signals of the M wavelength conversion circuits connected to M outputs of the N input M output merging / distributing distributors. And output N M input combiners (61-1 to 61-
4) and N wavelengths which are the combined outputs from the M input combiners and take in the M-channel optical signal consisting of M wavelengths and separate and output them into N outputs at any combination of wavelengths. A wavelength division type optical communication path comprising at least separation circuits (60-21 to 60-24). 5. An N-type optical highway configured by dividing light into M wavelengths, multiplexing each of the M wavelengths as a signal channel, and using the M wavelengths as an M channel is defined as an input highway. In a wavelength division type optical communication path in which signal channels are switched as desired on the highway and then output as N output highways (where M and N are natural numbers of 2 or more), N wavelength demultiplexers (80-1) that take in optical signals of M channels consisting of M wavelengths on the highway, separate them into signal channels of respective wavelengths, and output
˜80-4), and N M inputs (N × M) that generate N × M outputs by using the M outputs that are wavelength separation outputs of the wavelength separators as inputs.
M) output space switches (81-11 to 81-14) and N M outputs of the M input (N × M) output space switches, respectively. N M-input mergers (82-1) and the output of each M-input merger, 1 for each input highway
It is connected to N pieces of N-input M-output merge distributors (33-1 to 33-4) for selecting M by output, merging, and distributing to M, and M outputs of each N-input M-output merge distributor. N × M wavelength conversion circuits (37) for extracting a 1-channel signal having an arbitrary specific 1 wavelength by wavelength conversion from an M-channel optical signal having M wavelengths, and the N-input M-output merging distribution N input M output merge distributors (34-1 to 34-34) that combine the output optical signals of the M wavelength conversion circuits connected to the M outputs of the converters and distribute N for each output highway. 4), and N for connecting to the N outputs of each of the M-input / N-output merging / distributing devices to extract signals of a plurality of channels having arbitrary wavelengths from M-channel optical signals of M wavelengths and outputting the signals. × N multiple wavelength selection filters (36-2)
A wavelength division type optical communication path comprising at least: 6. N-number of optical highways configured by dividing light into M wavelengths, multiplexing each of the M wavelengths as a signal channel and M wavelengths as M channels, and inputting the input highways. In a wavelength division type optical communication path in which signal channels are switched as desired on the highway and then output as N output highways (where M and N are natural numbers of 2 or more), N N optical signals that take in M optical signals of M wavelengths on the highway
Distributors (32-1 to 32-4) and a plurality of channels of an arbitrary combination of a plurality of wavelengths, which are connected to the N outputs of the respective N distributors, from an optical signal of M channels of M wavelengths. N × N multiple wavelength selection filters (36-1) for extracting and outputting optical signals and outputs of each of the multiple wavelength selection filters are selected one by one for each input highway, merged, and M-distributed. N N
Input M output merging / distributor (33-1 to 33-4) and M output of each of the N input M output merging / distributor, and arbitrarily specified from M channel optical signals having M wavelengths. N wavelength conversion circuits (37) for extracting a 1-channel signal consisting of 1 wavelength by wavelength conversion, and the M wavelengths connected to the M outputs of the N input M output merge distributors. The optical signal output from the conversion circuit is used as an input for N
N M input (N × M) output space switches (81-21 to 81-24) that generate × M outputs and N M outputs of the M input (N × M) output space switches, respectively. A wavelength division type optical communication path comprising at least N × N M input combiners (82-2) which are connected to each other and take in and combine and output the M outputs. 7. The optical highway, which is constructed by dividing light into M wavelengths, multiplexing each of the M wavelengths as a signal channel, and using the M wavelengths as an M channel, is set as an input highway, and the input highway is input. In a wavelength division type optical communication path in which signal channels are switched as desired on the highway and then output as N output highways (where M and N are natural numbers of 2 or more), N wavelength demultiplexers (80-1) that take in optical signals of M channels consisting of M wavelengths on the highway, separate them into signal channels of respective wavelengths, and output
˜80-4), and N M inputs (N × M) that generate N × M outputs by using the M outputs that are wavelength separation outputs of the wavelength separators as inputs.
M) output space switches (81-11 to 81-14) and N M outputs of the M input (N × M) output space switches, respectively. N M-input mergers (82-1) and the output of each M-input merger, 1 for each input highway
It is connected to N pieces of N-input M-output merge distributors (33-1 to 33-4) for selecting M by output, merging, and distributing to M, and M outputs of each N-input M-output merge distributor. N × M wavelength conversion circuits (37) for extracting a 1-channel signal having an arbitrary specific 1 wavelength by wavelength conversion from an M-channel optical signal having M wavelengths, and the N-input M-output merging distribution The optical signals output from the M wavelength conversion circuits connected to the M outputs of the optical fiber are input as N
N M input (N × M) output space switches (81-21 to 81-24) that generate × M outputs and N M outputs of the M input (N × M) output space switches, respectively. A wavelength division type optical communication path comprising at least N × N M input combiners (82-2) which are connected to each other and take in and combine and output the M outputs.