JPH11136711A - Optical cross connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the space utility by making its own station act as a relay station and routing an optical pulse series transferred from other station to a different other station as the optical signal without converting it into an electric signal. SOLUTION: Optical time division devices 140-142 divide a short pulse optical signal in time division multiplex transferred from other station into pluralities of optical pulse series. Those optical pulse series are matched in timing and given to an optical spatial switch 170. The optical spatial switch 170 switches routes and outputs them without conversion. Those optical pulse series going to the same station among pluralities of the outputted optical pulse series are time-adjusted and transferred in time division multiplex to the same station.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an optical cross-connect device used for an optical communication network system.

[0002]

2. Description of the Related Art Information communication networks are shifting to the era of broadband ISDN represented by services such as video communication. Here, it is assumed that an ultra-high-speed optical transmission system is adopted. To satisfy this premise, the development of ultrashort optical pulse communication technology using a short pulse optical signal has been strongly promoted. Here, the short pulse optical signal refers to an optical pulse signal in which the light emission time is extremely short compared to the pulse repetition period. At the same time, the development of the multiplexing technology of the ultrashort optical pulse communication technology has been strongly advanced.

[0003]

However, the above-mentioned conventional techniques have the following problems to be solved. A relay station is required for a relay station of the broadband ISDN. In this relay device, both the input signal and the output signal are optical pulses. However, inside the relay device, all the signals are processed in the order of light → electricity → electrical switching →→ electricity → light. The equipment required for this has been implemented, so the equipment in the office has increased and the space utility has increased. At the same time, there remain problems to be solved, such as an increase in power consumption and an increase in cost.

[0004]

The present invention adopts the following constitution in order to solve the above points. <Structure 1> An optical time division device that separates a time-division multiplexed short pulse optical signal into a plurality of optical pulse sequences before multiplexing, and selects one from the separated optical pulse sequences. By shifting in the time axis direction, an optical delay line that matches the transfer timing of all optical pulse sequences, and a plurality of optical pulse sequences that match the transfer timing are input,
The optical signal is switched in the direction of the optical signal, and an optical space switch to be output toward a desired route and a plurality of optical pulse sequences output from the optical space switch are selected and selected in the time axis direction. The optical delay line which makes the transfer timing of all the optical pulse sequences different from each other, and receives the optical pulse sequence which makes the output timing different,
A time-division multiplexing optical coupler.
Optical cross connect device.

<Structure 2> In the device described in Structure 1,
An optical delay line that delays a certain time for each optical pulse sequence, separates output timings between the optical pulse sequences and matches the timing of time division multiplexing, and a short pulse that generates a short pulse optical signal with a desired repetition period. A generator and an optical modulator that optically modulates the optical pulse sequence generated by the short pulse generator with information to be transmitted. A transmitting device for inputting to the optical space switch at the same timing as the pulse sequence, and an output terminal for taking out the optical pulse sequence transferred from another station to the local station as an optical signal from the optical space switch, and an output terminal. Optical cross-connect device.

<Structure 3> In the device described in Structure 1,
The pulse repetition periods of the short-pulse optical signals input to the N optical time-division devices are denoted by t1 to tN, respectively, and the number of optical pulse sequences separated by the N optical time-division devices is n1 to nN.
The optical cross-connect device maintains a relationship of t1 × n1 = t2 × n2 =... TN × nN.

<Structure 4> In the device described in Structure 2,
The pulse repetition periods of the short-pulse optical signals input to the N optical time-division devices are denoted by t1 to tN, respectively, and the number of optical pulse sequences separated by the N optical time-division devices is n1 to nN.
And a short pulse generator possessed by the transmitting device is generated,
When the pulse repetition period of the short pulse optical signal is T,
An optical cross-connect device that holds a relationship of t1 × n1 = t2 × n2 =... tN × nN = T.

<Structure 5> In the device described in Structure 1,
An optical cross-connect device, wherein a part or all of an optical delay line for shifting an optical pulse sequence in a time axis direction is configured by a delay time variable optical delay line.

<Structure 6> An optical time division device that separates a time-division multiplexed short pulse optical signal into a plurality of optical pulse sequences before multiplexing, and a time axis dividing each of the plurality of separated optical pulse sequences. In the direction, the delay time variable optical delay line that adjusts the phase of each optical pulse sequence to a time-division multiplexed state on the output side path, and receives the timing-adjusted optical pulse sequences. An optical spatial switch that receives a short-pulse optical signal bit by bit from a plurality of optical pulse sequences in a predetermined order from the plurality of optical pulse sequences, and time-division multiplexes and outputs the signal toward the desired path. Optical cross-connect device.

<Structure 7> An optical time division device that separates a time-division multiplexed short pulse optical signal into a plurality of optical pulse sequences before multiplexing, and a time axis dividing each of the plurality of separated optical pulse sequences. In the direction, the delay time variable optical delay line that adjusts the phase of each optical pulse sequence to a time-division multiplexed state on the output side path, and receives the timing-adjusted optical pulse sequences. An optical space switch for time-division multiplexing and outputting to the desired path by a converging function including a plurality of optical pulse sequences therein as an optical signal. .

<Structure 8> In the apparatus according to any one of Structures 1 to 7, the wavelength division multiplexed short pulse optical signal is received and separated into short pulse optical signals of respective wavelengths. The optical multiplexer is provided on the input side of a plurality of optical time division devices, and an optical wavelength multiplexer for combining optical pulse sequences of different wavelengths, which are optical pulse sequences output from the optical space switch, is provided. An optical cross-connect device.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments. FIG. 1 is a block diagram of the optical cross-connect device according to the first embodiment. Before describing the optical cross-connect device according to the specific example 1, the entire optical repeater will be described with reference to a comparative example in order to facilitate understanding of the present invention.

(Configuration of Optical Transmitting / Receiving Apparatus According to Comparative Example) FIG. 2
FIG. 3 is a block diagram of an optical transceiver according to a comparative example. The optical transmitting / receiving device according to the comparative example includes a transmitting device 200, a receiving device 251, and an optical fiber 290 connecting the two devices. The transmission device 200 includes a short pulse generator 102
, The optical splitter 106, the optical delay lines 208 and 210, the optical modulators 120, 121 and 122, and the modulator driver 11
5, 116 and 117, and an optical combiner 242. The receiving device 251 includes an optical time division device 252, regenerators 262,
64, 266.

The short pulse generator 102 is an optical signal generator that generates a short pulse optical signal. The optical splitter 106 is a splitter that splits the short-pulse optical signal generated by the short-pulse generator 102 into N and outputs the split signal. Optical delay lines 208, 210
Is a portion for delaying the input optical pulse sequence by a very short time t / N per loop. Here, t is a pulse repetition period, and N is the number of branches of the optical branching unit 106. The optical modulators 120, 121, and 122 are portions that modulate optical pulses with electric signals applied by modulator drivers 115, 116, and 117.

The modulator drivers 115, 116 and 117 convert the electric signals input to the input terminals into optical modulators 120 and 12 respectively.
1 and 122. Optical merger 24
Reference numeral 2 denotes a portion for time-division multiplexing the output signals of the optical modulators 120, 121, and 122. The optical time division device 252 is a part that sequentially distributes the input short pulse optical signal to a plurality of output terminals and outputs the signal as an optical pulse sequence. For example, it is realized by an ultrafast optical space switch. Regenerator 262,
Numerals 264 and 266 are parts for converting an input optical pulse sequence into an electric signal and outputting the electric signal.

(Operation of Optical Transmitting / Receiving Apparatus According to Comparative Example) The short pulse generator 102 generates a short pulse signal at a time interval t and transfers it to the optical splitter 106. The optical splitter 106 splits this short pulse signal into three and outputs it as three optical pulse sequences. Here, the number of branches N is assumed to be 3 for ease of explanation.
Set as One output sequence of the optical pulse sequence that is output after being branched into three is transferred to the optical modulator 120 as it is. The other two output sequences are transferred to optical modulators 121 and 122 through optical delay lines 208 and 210, respectively. As a result, between the optical pulse sequences 212 and 214 input to the optical modulators 120, 121 and 122, t / 3 time, 212 and 2
There is a time difference of 2t / 3 hours between the sixteen.

The optical modulators 120, 121, and 122 convert the three optical pulse sequences into input terminals 230, 232, and 23, respectively.
The information based on the electric signal input from 4 is loaded and transferred to the optical combiner 242. The optical combiner 242 performs time division multiplexing of the three optical pulse sequences to form one optical fiber 290.
To be transmitted. At this time, since the three optical pulse sequences have a time difference of t / 3 time and 2t / 3 time, no collision occurs between the optical pulse sequences.

The time-division multiplexed optical pulse sequence 244 is
The signal is transmitted through the optical fiber 290 and transferred to the optical time divider 252 inside the receiving device 251. The optical time division device 252 sequentially outputs the input optical pulses to a plurality of output terminals.
Therefore, the output optical pulse sequence 254, 256, 258
Are three optical pulse sequences 212, 2
14, 216. These three light pulse sequences 21
2, 214, 216 are regenerators 262, 264, 266
Is converted into an electric signal and output.

Next, an optical cross-connect device constituted by using the above-described optical transmission / reception device will be described. FIG.
FIG. 4 is a block diagram of an optical cross-connect device according to a comparative example. The optical cross-connect device according to the comparative example includes receiving devices 301, 302, and 303, and transmitting devices 311, 312,
313 and an electric switch 320. Receiver 3
01, 302, and 303 correspond to the receiving device 251 (FIG. 2).
It is. The transmitting devices 311, 312, and 313 are the transmitting device 200 (FIG. 2).

The electric switch 320 time-division multiplexes a signal input from the local input terminals 331, 332, 333 with a relay signal received from another station through the input terminals 351, 352, 353, and outputs an output terminal 361. , 362, 3
It transmits to other stations through 63. Also, the input terminal 351,
Signals transferred from another station to the own station through 352 and 353 are transmitted to local terminals 341, 342 and 34.
Output from 3. Further, the input terminals 351, 352, 35
The relay signal to another station received through the terminal 3 is output to the output terminal 36.
1, 362 and 363 to transfer to another station. All of the above operations are processed through the conversion of light → electricity → electrical switching → electricity → light. As a result, there are still problems to be solved, such as an increase in in-station equipment, an increase in space utility, an increase in power consumption and an increase in cost.

<Structure of Embodiment 1> Returning to FIG.
The configuration of the optical cross-connect device will be described.
The optical cross-connect device according to the specific example 1
0, N optical time dividers 140, 141, 142 (here, limited to N = 3 for convenience of explanation), an optical space switch 170, and N optical multiplexers 190, 191, 192.
(Here, N = 3 for convenience of explanation) and N × 3 on the input side and the output side of the optical space switch 170, respectively.
(N-1) optical delay lines 150 to 157, 181 to 18
8 (here, limited to N = n = 3 for convenience of explanation).

Further, the transmitting apparatus 100 includes a short pulse generator 102, an optical splitter 106, m optical modulators 120,
121 and 122 (here, m = 3 for convenience of explanation) and m modulator drivers 115, 116, 11
7 (here, limited to m = 3 for convenience of explanation).

The short pulse generator 102, the optical splitter 106,
Optical modulators 120, 121, 122, modulator driver 11
5, 116 and 117 are the same as in the comparative example. The optical time dividers 140, 141, and 142 sequentially transmit short pulse optical signals, which are time-division multiplexed and transferred from other stations through the optical fibers 130, 131, and 132 connected thereto, to a plurality of output terminals. This is a portion that is distributed and output as an optical pulse sequence. For example, it is realized by an ultrafast optical space switch. The optical space switch 170 performs a switching process on the optical pulse sequence input from the (N × n) + m sequence as it is, without converting it into an electric signal, and converts the optical pulse sequence into an (N × n) + m sequence. This is the output part. Here, for convenience of explanation, N = n = m = 3 is limited.

Optical delay lines 151, 154, 157, 18
1, 184 and 187 are portions that are delayed by a very short time t. Here, t is an optical fiber 130, 131, 1
32 is the repetition period of the pulse transferred to the optical time division device 140, 141, 142. Similarly, the optical delay lines 150, 153, 156, 182, 185, 188
This is a portion that is delayed by a minute time 2t. The optical couplers 190, 191 and 192 are parts that time-division multiplex the output signals of the optical space switch 170.

<Operation of Specific Example 1> A short-pulse optical signal transmitted from the optical fiber 130 connected to another station to the input of the optical time-division multiplexer 140 is sequentially distributed to three output terminals to generate an optical pulse. Output as a series. One of these optical pulse sequences is delayed by 2t through the optical delay line 150, the other is delayed by t time through the optical delay line 151, and the remaining one is left as it is by the optical space switch 170. Reach the input. Therefore, these three optical pulse sequences are input to the optical space switch 170 at the same time. The short pulse light signals transferred from the optical fibers 131 and 132 connected to the other stations are input in the same way to the optical space switch 170 at the same time.

The short pulse generator 102 generates a short pulse signal at a time interval T and transfers it to the optical splitter 106. The optical splitter 106 splits this short pulse optical signal into three and outputs it. The optical pulse sequence output after being branched into three is directly transferred to the optical modulators 120, 121, and 122. The optical modulators 120, 121, 122 carry the information input from the local input terminals 110, 111, 112 on these three optical pulse sequences and transfer them to the optical space switch 170. Here, the time interval T is set to T = 3t, and the timing of the optical pulse sequence is made to coincide in advance with the timing at which the optical pulse sequence transferred from the other station is input to the optical space switch 170.

The optical space switch 170 is connected to the optical pulse series transmitted through the optical fibers 130, 131, and 132 connected to the other stations, and to the local input terminal 110,
An optical pulse sequence carrying information input from 111 and 112 is input simultaneously. By switching an ultra-high-speed optical space switch possessed inside, each optical pulse sequence is output along a route to be transferred. Local output terminal 16
The optical pulse sequences output from 5, 166, and 167 are directly transferred to the line in the own station.

A relay optical pulse sequence toward another station, for example, one of three optical pulse sequences toward the optical fiber 195.
The sequence is transferred to the optical combiner 190 as it is. Another series is delayed by the optical delay line 181 for the delay time t, and the remaining series is delayed by the optical delay line 182 for the delay time 2t, and transferred to the optical coupler 190. The three optical pulse sequences having a mutual delay time difference are time-division multiplexed by the optical multiplexer 190 and transferred to another station. At this time, since there is a time difference between the three optical pulse sequences, no collision occurs during multiplexing.

<Effect of Specific Example 1> The optical cross-connect device according to the specific example 1 is different from the electric switch 320 according to the comparative example.
By providing the optical space switch 170 instead of (FIG. 3), the following effects were obtained. 1. The own station becomes a relay station, and the optical pulse sequence transferred from another station to another station is selected as a light path without being converted into an electric signal. As a result, a light-to-electricity-to-light conversion facility is no longer required, and the space utility is greatly reduced. 2. For the same reason, it has become possible to reduce the power consumption and the cost of the station equipment.

<Embodiment 2> FIG. 4 is a block diagram of an optical cross-connect device according to Embodiment 2. Only differences from the first specific example will be described. In the specific example 1 (FIG. 1), the pulse speeds transmitted from the optical fibers 130, 131, and 132 connected to other stations are equal, and the pulse repetition periods are all equal, and the time is t. In the specific example 2, the speed of the short-pulse optical signal transferred from the N optical fibers 130, 131, and 132 (here, limited to N = 3 for convenience of explanation) connected to another station is different, and pulse repetition is performed. It is assumed that the periods are different.

For example, it is assumed that t1 in the optical fiber 130, t2 in the optical fiber 131, and t3 in the optical fiber 132. In order to operate the optical space switch 170 normally in this state, it is necessary to input an optical pulse sequence with the same pulse repetition period T and simultaneous timing. Accordingly, the number of branches n of each of the optical time division devices 140, 141, 142
1, n2, and n3 must satisfy the following relationship. t1 × n1 = t2 × n2 = t3 × n3 = T Equation (1) As shown in FIG. 4, n1 = 2, n2 = 3, and n3 =
Assuming that 4, t1 = T / 2 and t2 =
T / 3 and t3 = T / 4 are obtained.

Further, in order to input an optical pulse sequence at the same time, optical delay lines 450 and 45 to be inserted in the path are provided.
The delay times of 2, 453, 455, 456, and 457 are represented by delay times t450, t452, t453, t455,
If t456 and t457 are set, the following is obtained. The above t
From t1, t2, t3 and t4, t450 = T / 2, t45
2 = 2T / 3, t453 = T / 3, t455 = 3T /
4, 456 = 2T / 4 and t457 = T / 4.

The delay time of the delay line on the output side of the optical space switch 170 can be obtained in the same manner. Here, all the optical delay lines can be replaced with delay time variable optical delay lines that can be changed to an arbitrary delay time. Other configurations and operations are the same as those of the first embodiment.

<Effects of Specific Example 2> The following effects can be obtained by selecting the delay time of the optical delay line and the number of branches of the optical time divider to desired values. 1. It is now possible to relay over trunk lines with different transmission speeds. 2. As a result, the multiplicity can be changed according to the traffic between the stations, so that an efficient link design has become possible. That is, conventionally, when the degree of multiplexing is adjusted to a link having a large traffic, the bandwidth is left over with a small link. Conversely, when the degree of multiplexing is adjusted to a link with low traffic, there are problems such as the necessity of increasing the number of optical fibers for a link with a large number of links.

Further, the following effects can be obtained by replacing the optical delay line with a variable delay time optical delay line. 3. It becomes much easier to change the multiplicity according to the traffic between stations. 4. When simultaneously inputting each optical pulse sequence to the optical space switch, and when multiplexing on an optical fiber to another station,
Timing adjustment becomes easy.

FIG. 5 is a block diagram of an optical cross-connect device according to a third embodiment. Example 2
Only the differences will be described. Optical modulators 120, 12
1, delay time variable optical delay element 550 after output of 122
Was arranged. The number of outputs of the optical space switch 570 is the local output p (here, p = 3 for convenience of explanation)
+ Number of output fibers L to other stations (here, for convenience of explanation, L
= 3). Optical fibers 195, 196, and 197 to other stations are connected directly to the output of the optical space switch 570. That is, it does not have the optical delay lines 250 to 257 (FIG. 4) and the optical couplers 190 to 192 (FIG. 4). Instead, it has another function.

FIG. 6 is an explanatory diagram of functions required for the optical space switch. The optical space switch 570 performs the optical pulse sequence 1
An ultra-high-speed switching function unit 500 that can fix the output path and switch the connection state of the input path for each bit
(FIG. 6A).

<Operation of Embodiment 3> The difference from Embodiment 2 will be described with reference to FIG. In the specific example 2 (FIG. 4), the input signal to the optical space switch 170 was adjusted by the optical delay lines 250 to 257 on the input path so that the input timings coincided. Further, the output signals were also output at the same timing, and after the output signals were adjusted using the optical delay lines 250 to 258. In the specific example 3, the timing adjustment at the two locations is combined at one location using the variable delay time optical delay element 550. An example will be described below.

It is now assumed that the optical pulse sequence A-1 transmitted by the optical fiber 130 and the optical pulse sequence B-2 transmitted by the optical fiber 131 are time-division multiplexed and transmitted to another station by the optical fiber 195. Assume that it is forwarded to Further, the optical fiber 130 and the optical fiber 195,
Optical fiber 131, optical fiber 196, optical fiber 13
2 and the optical fiber 197 are assumed to have the same transmission rate. T1 × n1 = t2 × n2 = T described in the specific example 2.
... It is necessary to satisfy the expression (1). Here, in order to simplify the description similarly to the specific example 2, as shown in FIG.
Assuming that 1 = 2 and n2 = 3, t1 =
T / 2 and t2 = T / 3 are obtained.

As a result, the light pulse sequence B-2 is changed to T / 2
When time-division multiplexed with the optical pulse sequence A-1 with a time delay, the pulse repetition period becomes t1, and the optical fiber 1
95 can be transmitted. By adjusting the variable delay time optical delay elements 550a and 550d, the difference in delay time of T / 2 time can be easily obtained. The optical space switch 570 fixes the output route of the optical pulse sequence to the optical fiber 195 and switches the input route to the optical pulse sequence A-1 and the optical pulse sequence B-2 for each bit, thereby performing the multiplexing. Can be performed without a collision (the function is shown in FIG. 6A). Hereinafter, the same operation can be performed by adjusting the delay time variable optical delay element 550 for all the optical pulse sequences.

In the above description, the optical space switch 570 is
The description has been made on the assumption that the direction switching of the optical pulse sequence is performed quickly. However, this is also possible by providing the merge function unit 501 (FIG. 6B) on the output side of the optical space switch 570. This merging function unit 501 (FIG. 6)
(B)) has the same function as the optical multiplexer 190 (FIG. 4) according to the second embodiment. By providing the merging function unit 501, it is not necessary to provide the ultra-high-speed switching function unit 500. Here, for convenience of explanation, the optical fiber 1
Although the transmission speeds of the optical fiber 30 and the optical fiber 195, the optical fiber 131 and the optical fiber 196, and the optical fiber 132 and the optical fiber 197 have been described as being equal, it is not necessary to limit to this assumption. If the value satisfies the above expression (1), the input / output transmission speed can be set arbitrarily. Furthermore, if an empty slot is assumed, it is possible to set more freely without satisfying the above-mentioned expression (1).

<Effect of Specific Example 3> The following effects can be obtained by providing the variable delay time optical delay element 550 and the ultra-high-speed switching function section 500. 1. It is not necessary to provide an optical delay line on the output side of the optical space switch. 2. The same effect can be obtained by providing the variable delay time optical delay element 550 and the merging function section 501 on the output side of the optical space switch 570.

<Structure of Embodiment 4> FIG. 7 is a block diagram of an optical cross-connect device according to Embodiment 4. Only differences from other specific examples will be described. The optical cross-connect device according to the specific example 4 includes an optical wavelength demultiplexer 742 and an optical wavelength multiplexer 748 at the input of the optical cross-connect device 701 according to the specific examples 1 to 3.

Further, the transmitting device 700 of the optical cross-connect device 701 according to the first to third embodiments includes a short pulse generator 702 with the number required for the number of optical wavelength multiplexes. Optical wavelength demultiplexer 7
Reference numeral 42 denotes a portion for separating the wavelength-multiplexed optical signal into an optical signal sequence for each wavelength. The optical wavelength multiplexer 749 is a part that multiplexes a plurality of optical signal sequences having different wavelengths.

<Operation of Specific Example 4> An optical signal transferred from another station is a wavelength multiplexed signal multiplexed by a plurality of light sources having different wavelengths λ. For example, it is assumed that a short-pulse optical signal transferred by the input fiber 741 is a signal multiplexed by two light sources having a wavelength λ1 and a wavelength λ2 (the number of multiplexes is limited to 2 for the sake of simplicity). I do. The multiplexed signal is supplied to an optical wavelength demultiplexer 7.
42, the signal sequence 743 (λ1) of the wavelength λ1 and the wavelength λ2
743 (λ2). The short-pulse optical signal separated for each wavelength has already been described in the first to third specific examples.

The operation of the short pulse optical signal is exactly the same as that of the first to third embodiments until it is input to the optical time division device 744 and thereafter to the optical wavelength multiplexer 748. However, the optical pulse sequence is time-division multiplexed within the same wavelength. The plurality of optical pulse sequences time-division multiplexed in the same wavelength (limited to two sequences of wavelength λ1 and wavelength λ2 in FIG. 7) are multiplexed by an optical wavelength multiplexer 748, and are combined with a wavelength multiplexed signal. And transferred to another station. Similarly, the transmitting device 7
The short pulse generator 702 also includes a plurality of light sources (limited to three in the figure) and generates optical pulse sequences of optical signal sequences having different wavelengths. All other operations can be replaced by any of the first to third examples.

<Effect of Specific Example 4> An optical wavelength demultiplexer 742 is connected to the input of the optical cross-connect device 701 according to specific examples 1 to 3.
In addition, by providing an optical wavelength multiplexer 749 at the output and performing wavelength multiplexing, it is possible to increase the utilization of the optical band, and as a result, it is possible to transmit more information.

[Brief description of the drawings]

FIG. 1 is a block diagram of an optical cross-connect device according to a specific example 1.

FIG. 2 is a block diagram of an optical transceiver according to a comparative example.

FIG. 3 is a block diagram of an optical cross-connect device according to a comparative example.

FIG. 4 is a block diagram of an optical cross-connect device according to a specific example 2.

FIG. 5 is a block diagram of an optical cross-connect device according to a third embodiment.

FIG. 6 is an explanatory diagram of functions required for an optical space switch.

FIG. 7 is a block diagram of an optical cross-connect device according to a specific example 4.

[Explanation of symbols]

REFERENCE SIGNS LIST 100 Transmitter 102 Short pulse generator 106 Optical splitter 110, 111, 112 Local input terminal 115, 116, 117 Modulator driver 120, 121, 122 Optical modulator 130, 131, 132, 195, 196, 197 Optical fiber 140 , 141, 142 Optical time divider 150, 151, 153, 154, 156, 157, 1
81, 182, 184, 185, 187, 188 Optical delay line 165, 166, 167 Local output terminal 170 Optical space switch 190, 191, 192 Optical coupler

Claims (8)

[Claims] 1. A time-division multiplexed short pulse optical signal is
An optical time-division device that separates the optical pulse sequences into a plurality of optical pulse sequences before multiplexing, selecting one of the separated optical pulse sequences and shifting in the time axis direction, An optical delay line for matching transfer timings, and a plurality of optical pulse sequences for which the transfer timings are matched are input, an optical signal is used to perform route switching, and an optical space to be output toward a desired route is output. A switch and one of a plurality of optical pulse sequences output from the optical space switch, and shifting in the time axis direction,
An optical cross, comprising: an optical delay line that makes transfer timings of all optical pulse sequences different from each other; and an optical coupler that receives the optical pulse sequences with different output timings and performs time division multiplexing. Connect device. 2. The optical delay line according to claim 1, wherein the optical delay line is delayed for a predetermined time for each optical pulse sequence, separates output timings between the optical pulse sequences, and coincides with time-division multiplexing timing. A short pulse generator that generates a short pulse optical signal having a desired repetition period; and an optical modulator that optically modulates an optical pulse sequence generated by the short pulse generator with information to be transmitted. A transmitter that generates an optical pulse sequence to be transmitted to the optical space switch at the same timing as another optical pulse sequence, and an optical space that transmits the optical pulse sequence transferred from another station to its own station as an optical signal An optical cross-connect device comprising: an output terminal to be taken out of a switch. 3. The apparatus according to claim 1, wherein the pulse repetition periods of the short-pulse optical signals input to the N optical time-division devices are respectively t1 to tN, and the N optical time-division devices are respectively separated. An optical cross-connect device, wherein the relationship of t1 × n1 = t2 × n2 =... TN × nN is maintained, where n1 to nN are the number of optical pulse sequences to be performed. 4. The apparatus according to claim 2, wherein the pulse repetition periods of the short pulse optical signals input to the N optical time dividers are respectively t1 to tN, and the N optical time dividers are respectively separated. T1 × n1 = t2 × n2 =... TN × nN where T1 is the pulse repetition period of the short pulse optical signal generated by the short pulse generator possessed by the transmitting device, An optical cross-connect device, which holds a relationship of = T. 5. The optical cross according to claim 1, wherein a part or all of the optical delay line for shifting the optical pulse sequence in the time axis direction is constituted by a delay time variable optical delay line. Connect device. 6. The time-division multiplexed short pulse optical signal is
An optical time-division device that separates into a plurality of optical pulse sequences before multiplexing, each of the plurality of separated optical pulse sequences is shifted in a time axis direction, and a phase of each optical pulse sequence is output on a path on an output side. A delay time variable optical delay line that adjusts to a time-division multiplexed state, the timing-adjusted, receives a plurality of optical pulse sequences, and remains as an optical signal, leaving a plurality of optical pulse sequences in a predetermined order from a short pulse optical signal. And an optical space switch for receiving, on a bit-by-bit basis, a time-division multiplexed signal toward the desired path and outputting the multiplexed signal. 7. The time-division multiplexed short pulse optical signal is
An optical time-division device that separates into a plurality of optical pulse sequences before multiplexing, each of the plurality of separated optical pulse sequences is shifted in a time axis direction, and a phase of each optical pulse sequence is output on a path on an output side. A delay time variable optical delay line that adjusts to a time-division multiplexed state, and the timing is adjusted, accepting a plurality of optical pulse sequences, as an optical signal, by a merging function including a plurality of optical pulse sequences therein, And an optical space switch for performing time-division multiplexing and outputting to the desired route. 8. The optical wavelength demultiplexer according to claim 1, wherein a wavelength-multiplexed short pulse optical signal is received and separated into short pulse optical signals of respective wavelengths. An optical pulse sequence output from an optical space switch, wherein
An optical cross-connect device comprising an optical wavelength multiplexer for multiplexing optical pulse sequences having different wavelengths.