JP2002176397A - Interface device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To highly accurately control an oscillation wavelength in simple circuit constitution. SOLUTION: A transmission part 1 is provided with a single wavelength light source part 90 provided with a plurality of unit circuits for inputting a plurality of optical signals 3 and outputting a plurality of the optical signals of different wavelengths, an optical multiplex part 106 for inputting a plurality of the optical signals outputted from the single wavelength light source part 90 and outputting a plurality of the inputted optical signals as one wavelength multiplexed optical signal 4 by multiplex, an inspection signal extraction means 105 for extracting a part of a plurality of the optical signals outputted from the single wavelength light source part 90 and inputting the extracted signal as an inspection signal 7 to the optical multiplex part 106 and operation control means 108 and 109 for detecting the inspection signal 7 inputted to the optical multiplex part 106, discriminating the state of the detected inspection signal 7 and outputting control signals for controlling the operation of the single wavelength light source part 90.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates particularly to WDM (Wa).
BACKGROUND OF THE INVENTION The present invention relates to the field of an optical communication system for performing communication using wavelength division multiplexing light, and relates to an interface device capable of monitoring a failure and controlling a shift of an oscillation wavelength without changing an operation state of the optical communication system.

[0002]

2. Description of the Related Art (Conventional Example 1) A first conventional example will be described.

FIG. 8 shows a configuration example of an interface device for performing communication using WDM light.

[0004] The interface device includes a transmitting unit 1 and a receiving unit 2.

[0005] The transmitting section 1 has a plurality of different wavelengths (λ ₁ ,
λ ₂ , λ ₃ ,..., λ _n ), and a plurality of upstream input terminals 101 to which the respective optical input signals are input, and an optical / electrical conversion circuit 102 composed of a plurality of unit circuits corresponding to each of them.
An amplification / identification circuit 103 composed of unit circuits corresponding to each of them; an electric / optical conversion circuit 104 composed of a plurality of unit circuits having predetermined oscillation wavelength characteristics different from each other; an optical multiplexing circuit 106; Output terminal 107
And are connected in series in this order.

[0006] The receiving section 2 includes an optical input / output terminal 111, an optical demultiplexing circuit 112, and an optical / optical circuit comprising a plurality of unit circuits respectively corresponding to outputs of the optical demultiplexing circuit 112 for a plurality of wavelengths.
An electric conversion circuit 113, an amplification identification circuit 114 formed of a unit circuit corresponding to each of them, an electric / optical conversion circuit 115 formed of a unit circuit corresponding to each of them, and a plurality of downstream output terminals 116 corresponding to each of them. Are connected in series in this order.

Here, a plurality of single-wavelength light sources are constituted by the optical / electrical conversion circuit 102, the amplification / identification circuit 103, and the electric / optical conversion circuit 104, and the optical / electrical conversion circuit 113, the amplification / identification circuit 114, and the electric / electrical The light conversion circuit 115 forms a plurality of single wavelength light receiving circuits.

In the above configuration, the upstream input terminal 101
When a plurality of optical input signals are input from the multiplexor, the plurality of optical input signals are converted into electric signals by an optical / electrical conversion circuit 102, and the electric signals are amplified and identified and reproduced by an amplification / identification circuit 103. Oscillating optical signals of different desired frequencies preset by the conversion circuit 104 with amplitudes corresponding to the optical input signals,
The plurality of optical output signals are multiplexed by the optical multiplexing circuit 106 to form one wavelength multiplexed optical signal, which is output to one upstream output terminal 107.

When one wavelength-division multiplexed optical signal is received through one downstream input terminal 111, the received optical signal is demultiplexed by an optical multiplexing circuit 112 into a plurality of received optical signals having different wavelengths. The received optical signal is optically / electrically converted by the optical / electrical conversion circuit 113, the amplification / identification circuit 114, and the electric / optical conversion circuit 115 for each received light wavelength, amplified, discriminated and reproduced, and the electric / optical The plurality of optical signals obtained by the conversion are respectively output through the corresponding plurality of downstream output terminals 116.

(Conventional Example 2) A second conventional example will be described. FIG. 9 shows an arrayed optical waveguide diffraction grating (AWG (Arraycd-Waveguide) utilizing interference of multiple light beams.
2 shows a configuration example of a (Grating) type optical multiplexing / demultiplexing circuit.

This array optical waveguide diffraction grating type optical multiplexing / demultiplexing circuit is formed by integrally integrating the optical multiplexing circuit 106 and the optical multiplexing / demultiplexing circuit 112. An optical multiplexing / demultiplexing circuit 117 having the function of the circuit 112 (see FIG. 8).

Reference numeral 201 denotes a substrate made of silicon or quartz, on which a lower cladding layer made of a silicon dioxide layer or the like is formed. On this substrate, a refractive index is set higher than that of the lower cladding layer. A silicon dioxide layer or the like doped with germanium as an impurity is deposited and patterned to form a core layer.
Further, an upper clad layer made of a silicon dioxide layer or the like is formed on the core layer, and these three layers constitute an optical waveguide.

Reference numeral 202 denotes one input waveguide, a so-called input terminal; 203, a plurality of input-side channel waveguides corresponding to the number of wavelengths to be split; and 204, an input-side slab waveguide. Each of the input wavelength-division multiplexed optical signals is radiated from the geometrically arranged radiating ports, and is condensed at each of the geometrically arranged condensing ports.

Reference numeral 205 denotes an array waveguide diffraction grating (AWG)
Which is substantially a plurality of parallel optical waveguides. Each light transmitted to the geometrically arranged light-collecting ports by the input-side slab waveguide 204 passes through this optical waveguide. A phase difference occurs in light.

Reference numeral 206 denotes an output side slab waveguide, which effectively demultiplexes a plurality of lights having different wavelengths from respective lights having a phase difference, and outputs a plurality of output side channel waveguides 207 (wavelengths to be demultiplexed). The same number).

Reference numeral 208 denotes a plurality of output waveguides corresponding to each of the output-side channel waveguides 207, that is, a plurality of output terminals.

The optical demultiplexing circuit 112 (see FIG. 8) is composed of components 202 to 208. On the other hand, the optical multiplexing circuit 106 (see FIG. 8) includes the components 212 to 218.

Reference numeral 212 denotes a plurality of input waveguides corresponding to a predetermined number of different wavelengths required for communication, so-called a plurality of input terminals. Reference numeral 213 denotes a plurality of input-side channel waveguides corresponding to the input waveguide. Reference numeral 214 denotes an input side slab waveguide, which radiates each of a plurality of input lights having different wavelengths from the geometrically arranged light emitting ports and collects the light at each of the geometrically arranged light collecting ports. Light.

Reference numeral 215 denotes an array waveguide diffraction grating (AWG)
Which is substantially a plurality of parallel optical waveguides. Each light transmitted to the light collecting ports geometrically arranged by the input side slab waveguide 214 passes through this optical waveguide, but since the respective lengths are different, each of the light passing therethrough is different. A phase difference occurs in light.

Reference numeral 216 denotes an output side slab waveguide, which effectively combines a plurality of lights having different wavelengths from the respective lights having a phase difference, converts the lights into wavelength multiplexed light, and outputs a plurality of output side channel waveguides. 217 (FIG. 9 shows a plurality of output-side channel waveguides, but usually only one of them flows through the wavelength-division multiplexed light).

Reference numeral 218 denotes one output waveguide for outputting a multiplexed wavelength multiplex signal, that is, an output terminal. In manufacturing this element, a manufacturing technique generally known as a planar optical waveguide manufacturing technique is used.

In the AWG optical multiplexing / demultiplexing circuit shown in FIG. 9, the optical waveguide circuit pattern for optical multiplexing and the optical waveguide circuit pattern for optical demultiplexing are integrally and partially overlapped. With this configuration, the chip area for forming the optical multiplexing / demultiplexing circuit is suppressed so as not to increase much more than the chip area for forming either the optical multiplexing circuit or the optical demultiplexing circuit, thereby preventing the production yield from deteriorating. Thus, a low-cost optical multiplexing / demultiplexing circuit is realized.

In such an optical waveguide type optical multiplexing / demultiplexing circuit, precise temperature control is performed on a chip in order to obtain a stable wavelength characteristic.
By using chips, the temperature control of both circuits can be made the same, and both economic efficiency and wavelength characteristic balance can be remarkably improved.

(Conventional Example 3) A third conventional example will be described.

FIG. 10 shows another example of the configuration of an interface device using WDM light.

The transmitting section 1 comprises the same components 101 to 107 as those shown in FIG. 8, but the receiving section 2 is constituted by omitting the components 113 to 115. That is, the receiving unit 2 includes the downstream input terminal 111 and the optical branching circuit 112.
And a plurality of downstream output terminals 116 respectively corresponding to outputs of a plurality of wavelengths of the optical demultiplexing circuit 112 are connected in series in this order.

The operation of the transmitting unit 1 is exactly the same as that of FIG. 8, but the operation of the receiving unit 2 is different. That is, when one wavelength multiplexed optical signal is received through one downstream input terminal 111, the received optical signal is demultiplexed by the optical demultiplexing circuit 112 to be a plurality of received optical signals having different wavelengths. Is output through a plurality of corresponding downstream output terminals 116 without performing optical / electrical conversion, amplification / identification reproduction, and electric / optical conversion.

In the interface device using WDM light shown in FIG. 10, since the optical / electrical conversion circuit 113, the amplification identification circuit 114, and the electric / optical conversion circuit 115 of the receiving section 2 are omitted, the number of parts is greatly reduced. , Economically Measured W
A DM optical interface device is realized.

In this case, the reason why the constituent elements 113 to 115 are omitted and the amplification / identification reproduction can be eliminated is as follows.
Recent one-chip AWG optical multiplexing as described in
This is because, in the demultiplexing circuit, the characteristic variation due to the insertion loss and the wavelength can be suppressed to a remarkably low level. This is because the transmission performance has been improved and the transmission loss has been kept sufficiently small.

If necessary, an optical amplifier is provided between the downstream input terminal 111 on the receiving side and the optical demultiplexing circuit 112, or between the optical multiplexing circuit 106 on the transmitting side and the upstream output terminal 107. It can be inserted to increase the signal amplitude.

[0031]

However, in the conventional interface device for performing communication using WDM light,
In order to increase the transmission efficiency of the optical communication system by increasing the optical wavelength multiplexing degree, the number of unit circuits of the single-wavelength light source unit of the transmitting unit 1 and the single-wavelength light receiving circuit of the receiving unit 2 is set to, for example, 16 to 32. Although it is common to use a large number of channels side by side, it is very difficult to inspect and monitor whether each unit circuit, especially each unit circuit of a single-wavelength light source, is operating normally in the system operation state. Have difficulty.

Conventionally, after switching the entire system or the WDM optical interface device to a spare system or a spare device due to a complaint from a customer of a communication system, expensive inspection / measurement is performed in a state where the system operation is suspended. It is necessary to diagnose a failure point of the WDM optical interface device by using the device and replace the component to recover.

Further, as another inspection function, it is required that the oscillation wavelength of each unit circuit of the single-wavelength light source be strictly and precisely controlled.
While it is required to stay within the range of ± 10 GHz at z intervals, it is impossible to inspect and monitor in the system operating state whether the control is performed within the normal range.

In order to cope with such a problem, conventionally, as a regular inspection mode, the system operation is interrupted, and the oscillation wavelength of each unit circuit of the E / O conversion circuit 104 of the single-wavelength light source is sequentially changed. The control setting value of the ambient temperature of each unit circuit of the conversion circuit 104 is sequentially set so as to measure and obtain a desired oscillation wavelength, and the set value is corrected.

However, such a solution requires a wavelength measuring device, which is an expensive precision measuring device, and can be implemented only in an inspection mode in which the system operation is interrupted. The realization of high-precision control was far from possible.

Accordingly, an object of the present invention is to provide an interface device capable of controlling the oscillation wavelength with high accuracy with a simple circuit configuration.

[0037]

SUMMARY OF THE INVENTION According to the present invention, there is provided a transmitter for combining a plurality of optical signals to output one wavelength multiplexed optical signal, and receiving and demultiplexing one wavelength multiplexed optical signal. An interface device having a receiving unit that outputs a plurality of optical signals of different wavelengths, wherein the transmitting unit has a plurality of unit circuits that receive a plurality of optical signals and output a plurality of different wavelength optical signals. A single-wavelength light source unit, and an optical multiplexing unit that receives the plurality of optical signals output from the single-wavelength light source unit and outputs the input plurality of optical signals as one wavelength-multiplexed optical signal by multiplexing; Test signal extraction means for extracting a part of the plurality of optical signals output from the single-wavelength light source unit, and inputting the extracted signals to the optical multiplexing unit as a test signal, and inputting the extracted signals to the optical multiplexing unit Said inspection signal Detects, by comprising an operation control means for outputting a control signal for to determine the state of the detected inspection signal controlling the operation of the single-wavelength light source unit, constitutes an interface device.

Here, the optical multiplexing unit may include an output terminal for normal output for outputting the wavelength multiplexed optical signal, and an output terminal for inspection for outputting the inspection signal.

The test signal extracting means is constituted by an optical switch circuit connected between the single-wavelength light source section and the optical multiplexing section, and the optical multiplexing section is directly connected to the single-wavelength light source section. An input terminal and an inspection input terminal connected via the optical switch circuit, wherein the optical multiplexing unit is provided from the unit circuit of the single wavelength light source unit through the input terminal. A plurality of optical signals are input, a test signal is input via the optical switch circuit and the test input terminal, and the input plurality of optical signals are output from the output terminal as the wavelength multiplexed optical signal. Along with
The inspection signal may be output from the inspection output terminal corresponding to each unit circuit of the single wavelength light source unit.

The operation control means includes: a first inspection for inspecting whether each unit circuit of the single-wavelength light source section is operating normally based on the detected inspection signal; A second inspection for inspecting the oscillation wavelength of the single-wavelength light source unit based on a signal, or a third inspection including both the first inspection and the second inspection is performed, and the first inspection is performed. A first output for outputting a control signal corresponding to the oscillation amplitude of each unit circuit of the single-wavelength light source unit based on the inspection result; and a unit output of the single-wavelength light source unit based on the inspection result of the second inspection A second output that outputs a control signal corresponding to the shift amount of the oscillation wavelength of, or the oscillation output of each unit circuit of the single-wavelength light source unit based on the inspection result of the third inspection, and The oscillation wavelength of each unit circuit of the single wavelength light source unit. A third output for outputting a control signal corresponding to preparative amount may be stabilized by performing.

The receiving section has a downstream input terminal for receiving the one wavelength multiplexed optical signal, and an optical demultiplexing section for demultiplexing the one wavelength multiplexed optical signal and outputting optical signals of a plurality of different wavelengths. A plurality of single-wavelength light-receiving units for amplifying and separating and reproducing the plurality of demultiplexed optical signals for each wavelength, and a downstream output terminal for outputting the reproduced optical signals;
Or a second circuit unit including the downstream input terminal, the optical demultiplexing unit, and the downstream output terminal.

The optical multiplexing section has a first circuit section having a normal steep transmittance / wavelength characteristic or a second circuit section having a lower transmittance / wavelength characteristic than the first circuit section. You may comprise as a circuit part.

The optical multiplexing section has two output terminals for inspection.
The inspection signal corresponding to the shift amount from the center wavelength may be obtained by division.

The optical multiplexing section includes an output terminal for normal output for outputting the wavelength multiplexed optical signal, and an output terminal for inspection adjacent to the output terminal for normal output. A leak output corresponding to the wavelength shift amount is detected as the test signal through the test output terminal,
The oscillation wavelength of the single wavelength light source unit may be monitored and stabilized based on the detected inspection signal.

The operation control means is a circuit for taking out a leakage output corresponding to the shift amount of the oscillation wavelength and monitoring and stabilizing the oscillation wavelength of the single-wavelength light source unit. A switch for sequentially electrically coupling the frequency oscillation circuit and each unit circuit of the single-wavelength light source unit, and a control output corresponding to the output level of the low-frequency component of the leakage output obtained from the inspection output terminal. And a temperature control circuit that controls the temperature of each unit circuit of the single-wavelength light source unit, and a switch that sequentially electrically couples the identification control circuit and the temperature control circuit.

The operation control means is a circuit for taking out a leakage output corresponding to the shift amount of the oscillation wavelength, monitoring the oscillation wavelength of the single wavelength light source section, and stabilizing the same. A low-frequency oscillation circuit composed of a unit circuit of the above, the low-frequency oscillation circuit and each unit circuit corresponding to the single-wavelength light source unit are electrically coupled, and each low-frequency component of the leakage output obtained from the inspection output terminal Extracting a plurality of unit circuits to obtain a plurality of control outputs corresponding to the output level of each low-frequency component, and a temperature control circuit of the unit circuit of the single wavelength light source unit, the identification The control circuit may be electrically coupled to a temperature control circuit of a corresponding unit circuit of the single wavelength light source unit.

The optical multiplexing / demultiplexing unit of the transmitting unit and the optical demultiplexing unit having the normal steep characteristic of the receiving unit may be configured as one optical multiplexing / demultiplexing unit.

Further, the following detailed configuration requirements may be adopted.

A plurality of optical input signals are supplied to a plurality of upstream input terminals, and optical signals whose light wavelengths have predetermined different wavelengths are oscillated at the intensities corresponding to the input signals and output as a plurality of optical output signals. A transmission unit having a plurality of single-wavelength light source devices, an optical multiplexing circuit for multiplexing the plurality of optical output signals and outputting the multiplexed optical signal as one light source output composed of one wavelength multiplexed optical signal to an upstream output terminal; The optical signal of a plurality of optical wavelengths is multiplexed through one downstream input terminal separately from the
An optical demultiplexing circuit that receives a received optical signal composed of two wavelength multiplexed optical signals, demultiplexes the received optical signal and outputs the received optical signal as a plurality of received optical signals having different wavelengths, A receiving section having a plurality of single-wavelength light receiving circuits for amplifying, discriminating, reproducing, and outputting to a downstream output terminal each time, wherein the optical multiplexing circuit outputs the ordinary wavelength multiplexed optical signal as an improved optical multiplexing circuit. And an output terminal for outputting an inspection signal in addition to the output terminal for performing the inspection, and an inspection signal corresponding to each unit circuit of the single-wavelength light source device is obtained from the inspection output terminal. A WDM optical interface device with a wave circuit is configured.

[0050]

Embodiments of the present invention will be described below in detail with reference to the drawings.

[First Example] A first embodiment of the present invention will be described with reference to FIG.

FIG. 1 shows an example of the configuration of an interface device for performing communication using WDM light according to the present invention.

(Interface Configuration) The present apparatus comprises a transmitting section 1 and a receiving section 2.

[0054] (transmission unit) transmitter 1, a plurality of different wavelengths _{(λ 1, λ 2, λ} 3, ..., λ n) and a plurality of uplink input terminal 101 which is an optical input signal 3 is inputted, this An optical / electrical (O / E) conversion circuit 102 including a plurality of unit circuits corresponding to each of the upstream input terminals 101, and an amplification identification circuit 103 including a unit circuit corresponding to each unit circuit of the optical / electric conversion circuit 102. And an electric / optical (E / O) conversion circuit 1 including a plurality of unit circuits having predetermined oscillation wavelength characteristics different from each other corresponding to each unit circuit of the amplification identification circuit 103.
04 and the optical switch circuit 10 as the inspection signal extracting means
5, an optical multiplexing circuit 106, and an upstream output terminal 107 for outputting _one wavelength multiplexed wavelength multiplexed optical signal 4 (λ ₁ , λ ₂ , λ ₃ ,..., Λ _n ) in series in this order. Connected to.

Here, the single-wavelength light source device 90 is constituted by the optical / electrical conversion circuit 102, the amplification identification circuit 103, and the electric / optical conversion circuit 104.

(Receiving Unit) The receiving unit 2 includes a downstream input terminal 111 to which one wavelength-multiplexed wavelength-multiplexed optical signal 5 (λ ₁ , λ ₂ , λ ₃ ,..., Λ _n ) is input, Demultiplexing circuit 112
And an optical / electric (O / O / O) comprising a plurality of unit circuits respectively corresponding to outputs of a plurality of wavelengths of the optical demultiplexing circuit 112.
E) Amplification discriminating circuit 1 composed of conversion circuit 113 and unit circuits corresponding to each unit circuit of optical / electric conversion circuit 113
14 and an electric / optical (E / O) conversion circuit 115 composed of unit circuits corresponding to the unit circuits of the amplification identification circuit 114.
Corresponding to each of the electric / optical conversion circuits 115,
A plurality of downstream output terminals 116 to which optical output signals 6 of a plurality of different wavelengths (λ ₁ , λ ₂ , λ ₃ ,..., Λ _n ) are respectively output.
And are connected in series in this order.

Here, the single-wavelength light receiving circuit 91 is constituted by the optical / electrical conversion circuit 113, the amplification / identification circuit 114, and the electric / optical conversion circuit 115.

(Inspection Circuit) This embodiment is characterized in that the following components are added.

In this device, the optical multiplexing circuit 106
On the input side, a plurality of normal input terminals 10 directly connected to the electric / optical conversion circuit 104 without passing through the optical switch 105
And a plurality of test input terminals 20 connected via an optical switch 105. On the output side,
One normal output terminal 30 and a plurality of inspection input terminals 40 for inspection are provided. Therefore, the optical switch 10
5 is electrically controlled in a time-series manner, whereby a signal input to the test input terminal 20 is controlled (passed or non-passed), and accordingly, the test input terminal 40 is controlled.
, The test signal 7 can be extracted in time series.

The normal input terminal 10 has more channel waveguides 11 than the number of unit circuits constituting the electric / optical conversion circuit 104, and corresponds to each unit circuit from the electric / optical conversion circuit 104. An optical output signal is directly input via the channel waveguide 11.

The inspection input terminal 20 has an inspection input waveguide 21 branched from each channel waveguide 11, and an optical output signal of each unit circuit from the electric / optical conversion circuit 104 is branched. Through the optical switch 105 connected to the channel waveguide 21 for each unit.

The output terminal 30 is provided corresponding to the normal input terminal 10, has a channel waveguide 31, and outputs the normal wavelength multiplexed optical signal 5 to the outside through the channel waveguide 31. .

The test output terminal 40 is connected to the test input terminal 2
0, and has a large number of output waveguides 41 for inspection, and outputs the inspection signal 7 corresponding to each unit circuit to the output waveguide 41 for inspection.

The test output terminal 40 is connected to the optical / electrical conversion circuit 108, the identification control circuit 109, and the temperature control circuit 130 in the electric / optical conversion circuit 104 via the test output waveguide 41. , In this order. The temperature control circuit 130 controls the electrical / optical conversion circuit 104 based on the control signal output from the identification control circuit 109.
Control the oscillation wavelength of

(System Operation) The operation of the present system will be described below.

(Transmitter) When a plurality of optical input signals 3 are input from the upstream input terminal 101, the plurality of optical input signals 3 are converted into electric signals by the optical / electrical conversion circuit 102, and the converted signals are input by the amplification / identification circuit 103. Amplifies and discriminates and reproduces electrical signals. After that, in the electrical / optical conversion circuit 104, optical output signals of different preset desired frequencies are oscillated with amplitudes corresponding to the optical input signals 3, respectively.

The optical output signal output from each unit circuit of the electric / optical conversion circuit 104 is output to the channel waveguide 11.
The optical signal is guided to the optical multiplexing circuit 106 and multiplexed to generate one wavelength multiplexed optical signal 4. This wavelength multiplexed optical signal 4 is output to the outside from one upstream output terminal 107 through the channel waveguide 31.

(Receiver) Also, one wavelength multiplexed optical signal 5
Is received through one downstream input terminal 111, the received wavelength-division multiplexed optical signal 5 is demultiplexed by the optical demultiplexing circuit 112 to obtain a plurality of received optical signals having different wavelengths. Then, the plurality of received optical signals having different wavelengths are converted into the optical / electrical conversion circuit 1.
13, a plurality of optical output signals obtained by performing optical-to-electric conversion, amplifying, discriminating and reproducing, and performing electric-to-optical conversion for each of the received light wavelengths by the amplification discriminating circuit 114 and the electric / optical converting circuit 115 6 correspond to a plurality of downstream output terminals 11 respectively.
6 and output each.

(Detection of Inspection Signal) On the other hand, an optical output signal output from each unit circuit of the electric / optical conversion circuit 104 is input to the improved optical multiplexing circuit 106 and output to the output terminal 107 for normal communication. At the same time as obtaining a multiplexed output of two wavelength multiplexed optical signals, the following detection processing is executed.

The optical output signal output from each unit circuit of the electric / optical conversion circuit 104 by the optical switch circuit 105 is transmitted through the input waveguide 21 for inspection to the optical switch circuit 10.
It is led to 5. And the input optical output signal is
The optical switch circuit 105 sequentially outputs one unit circuit at a time.
The signal is input to the inspection input terminal 20 of the improved optical multiplexing circuit 106. As a result, as will be described in detail later with reference to FIG. 3, the inspection signal 7 is output from the inspection output terminal 40 of the optical multiplexing circuit 106 through the inspection output waveguide 41. These inspection signals 7 are transmitted to the optical / electrical conversion circuit 10.
At 8, it is converted into an electric signal and sent to the identification control circuit 109.

Thereafter, in the discrimination control circuit 109, based on the converted electric signal, the electric / optical conversion circuit 1
Control signals indicating levels corresponding to the magnitude of the oscillation amplitude and the shift amount from the center value of the oscillation wavelength corresponding to each unit circuit of No. 04 are sequentially generated one by one unit circuit. in this case,
Of the inspection output terminals 40, the shift direction from the center value of the oscillation wavelength can be determined based on the difference between the output from the upper terminal and the output from the lower terminal. The identification information is sent from the identification control circuit 109 to the temperature control circuit 130 of the electrical / optical conversion circuit 104 as a control signal. Thereby, the temperature control circuit 130
Thus, the temperature of each unit circuit of the electric / optical conversion circuit 104 can be controlled in accordance with the control increase / decrease amount indicated by the control signal.

As a result, the oscillation amplitude of each unit circuit of the electrical / optical conversion circuit 104 can be monitored and normal operation can be confirmed without interrupting the system operation, and the shift amount of the oscillation wavelength can be monitored, controlled, and stabilized. The monitoring, control, and stabilization operations can be performed by sequentially switching the target unit circuits.

As described above, the optical switch circuit 105
A test input waveguide 21 added in the optical switch circuit 105; a test input terminal 20 and a test output terminal 40 added in the optical multiplexing circuit 106;
The electric conversion circuit 108, the identification control circuit 109,
Since the temperature control circuit 130 for controlling the temperature of each unit circuit of the optical conversion circuit 104 is sequentially connected, the electric / optical system can be operated without introducing an expensive wavelength measuring device and without interrupting system operation. The shift of the oscillation wavelength of each unit circuit of the conversion circuit 104 is individually and sequentially monitored and controlled.
Can be stabilized.

[Second Example] A second embodiment of the present invention will be described with reference to FIGS. The description of the same parts as those in the first example is omitted, and the same reference numerals are given.

FIG. 2 shows an AWG optical multiplexing / multiplexing circuit composed of the optical multiplexing circuit 106 and the optical demultiplexing circuit 112 shown in FIG.
4 shows an example of an improved configuration of the branching circuit 117.

The AWG optical multiplexing / demultiplexing circuit 117 can be basically realized by substantially the same configuration and manufacturing method as the conventional AWG optical multiplexing / demultiplexing circuit shown in FIG.

In the present embodiment, the number of channel waveguides of the optical multiplexing circuit 106 is larger than the number of predetermined wavelengths required for communication, for example, 2 to 4 times, and the input terminal for communication is used. In addition to the number of normal input terminals 10 corresponding to the number of wavelengths of the optical input signal 3 of the above, an inspection input terminal 20 for obtaining a single wavelength inspection optical output is derived.

The output terminal also has one or more test output terminals for outputting the test signal 7 in addition to the normal one output terminal 30 for outputting the multiplexed output of the wavelength multiplexed optical signal 4. The difference is that 40 is derived.

(Transmitting unit) 201 is a substrate, and 212 is a plurality of input waveguides (input terminal side) of 2 to 4 times the number of predetermined different wavelengths required for communication.

Reference numeral 213 denotes a plurality of input-side channel waveguides corresponding to the input waveguide 212. Reference numeral 214 denotes an input-side slab waveguide. 215 is an arrayed waveguide (AW
G). 216 is an output side slab waveguide. 2
Reference numeral 17 denotes a plurality of output-side channel waveguides corresponding to the number of the input-side channel waveguides 213.

Reference numeral 218 denotes one output waveguide 31 for outputting the multiplexed wavelength multiplexed signal 4 and one or more test output waveguides 41 (output terminal side).

The components 212 to 218 constitute the optical multiplexing circuit 106 shown in FIG.

The (receiving unit) 202 is one input waveguide (input terminal side).

Reference numeral 203 denotes a plurality of input-side channel waveguides corresponding to a predetermined number of wavelengths to be received and demultiplexed. Reference numeral 204 denotes an input-side slab waveguide. 205 is
An array waveguide (AWG). 206 is an output side slab waveguide. Reference numeral 207 denotes a plurality of output-side channel waveguides for each demultiplexed wavelength.

Reference numeral 208 denotes a plurality of output waveguides (output terminal side) corresponding to the output-side channel waveguides 207, respectively.

These components 202 to 208 constitute the optical demultiplexing circuit 112 shown in FIG.

(Wavelength Characteristics) FIGS. 3 and 4 show a configuration example of the transmittance and wavelength characteristics of the improved AWG optical multiplexing / demultiplexing circuit 117, and a method of obtaining an inspection signal using the same.

FIG. 3A shows an AWG optical multiplexing circuit 106 having twice the number of 2n channels as usual, and the output terminals other than the normal output terminal * J are not shown.

FIG. 4A shows the wavelength of the input terminal viewed from the output terminal * J when the AWG optical multiplexing circuit 106 of FIG. 3A is used as a normal optical multiplexing circuit having 2n channels. Shows transmission characteristics.

In FIG. 4A, the input wavelength is λ ₁ ,
Although only the odd-numbered suffixes of λ ₃ ,... are shown, the wavelength transmission characteristics including the input wavelengths of the even-numbered suffixes are shown.

(Characteristic Example 1) Next, FIG. 3B shows a case where the present invention is used as an improved AWG optical multiplexing circuit 106 according to the present invention.

FIG. 4B shows input wavelengths λ ₁ , λ ₃ ,... Of odd-numbered suffix numbers input to odd-numbered suffix-numbered input terminals # 1, # 3,. In this case, the transmission wavelength characteristic viewed from the normal output terminal * J is shown.

FIG. 4C shows a case where the same input wavelengths λ ₁ , λ ₃ ,... Are inputted to the input terminals # 4, # 6,. 3B shows the transmission wavelength characteristic viewed from the inspection output terminal * J + 3.

As for the input wavelength for inspection, instead of inputting all the wavelengths λ ₁ , λ ₃ ,... At the same time, input the input wavelength λ ₁ to the input terminal # 4 and then input to the input terminal # 6. Wavelength λ ₃
Enter the optical switch 1
In FIG. 4C, an optical output signal of wavelength λ ₁ is output to the output terminal * J + 3, and then an optical output signal of wavelength λ ₃ is output. Thus, a single-wavelength optical output signal is sequentially obtained.

At this time, for example, if the input wavelength λ ₁ input to the input terminal # 4 has an oscillation wavelength deviated from the center wavelength value, as shown in FIG. 3B, the inspection output terminal * J
A leakage output component appears at the output terminal * J + 4 or * J + 2 adjacent to +3, and as shown in FIG.
_According to whether the direction of deviation from the center wavelength value of ₁ is the long wavelength λ ₃ side (input terminal # 5 side) or the short wavelength λ _n side (input terminal # 3 side), the leakage output is the output terminal * J + 4. Or output terminal * J +
Two appear.

As described above with reference to FIGS. 3 and 4, by sequentially inputting the inspection input optical signals using the improved AWG optical multiplexing circuit 106 according to the present invention, the three From the inspection output terminal 40, an inspection light output corresponding to the oscillation amplitude of the inspection input optical signal of each wavelength, and an inspection corresponding to the shift amount of the oscillation wavelength of the inspection input optical signal to the longer wavelength side. The optical output for inspection, the optical output for inspection corresponding to the shift amount of the oscillation wavelength of the input optical signal for inspection to the short wavelength side, and the three optical outputs for inspection are sequentially output corresponding to each input wavelength. Can be.

(Characteristic Example 2) A further improved AWG optical multiplexing circuit 106 according to the present invention will be described.

In FIG. 3C, a leak output for inspection corresponding to the shift amount of the input wavelength is not obtained from the adjacent output terminals * J + 4 and * J + 2 as shown in FIG.
As shown in FIG. 4 (e), the transmission wavelength characteristic of the inspection output terminal * J + 3 is set to a wavelength characteristic obtained by dividing the transmission wavelength characteristic into two with the center wavelength as a boundary line.
From +31 and * J + 32, it is possible to obtain the inspection light output according to the shift amount from the center wavelength value of the input wavelength.

In this case, the inspection light output is 3
Instead of the book, the inspection light output corresponding to the shift amount of the oscillation wavelength of the inspection input optical signal to the longer wavelength side, and the shift amount of the oscillation wavelength of the inspection input optical signal to the shorter wavelength side were corresponded. 1 and 3 (b), except that two inspection light outputs with the inspection light output are obtained, and the inspection light output corresponding to the oscillation amplitude of the inspection input optical signal is not obtained. The monitoring and control of the oscillation wavelength can be performed in exactly the same manner as described above. Although not described in detail here, a further improved AWG optical multiplexing circuit having such output characteristics can be easily configured.

In the description of FIGS. 3B and 4C, the case where the test input signal λ ₁ is input to the test input terminal # 4 has been described as an example. When inputting to the input terminal for inspection of No. 6, the output terminal for inspection is
It goes without saying that almost the same operation and effect can be obtained simply by changing from J + 3 to another terminal.

By setting the input terminal, the inspection output terminal can be set at a position distant from the normal output terminal * J to some extent.

In the above description, the detailed description of why such an input / output characteristic is obtained by the improved AWG optical multiplexing circuit 106 is a well-known technique, and the description thereof is omitted. I do.

(Modification) Next, a modification will be described.

(Modification 1) The optical multiplexing circuit 106 is a circuit having a redundant input optical waveguide and an output optical waveguide, and has a wavelength gap of the input single wavelength light that uses the wavelength gap of the input single wavelength light. It may be configured as a circuit set to 1/2 to 1/4.

Hereinafter, a specific description is given.

In the improved optical multiplexing circuit 106 shown in FIGS. 3 and 4, the wavelength gap between adjacent wavelengths of the oscillation wavelength used for communication is set to, for example, 100 GHz. Has a transmittance / wavelength characteristic of 50 GHz
This is an example designed for a gap.
The leakage output corresponding to the deviation of the oscillation wavelength of the input optical signal for inspection at the wavelength gap of 0 GHz can be detected with greater sensitivity and higher sensitivity than in the case of the optical multiplexing circuit designed for the 100 GHz gap, and the oscillation wavelength is controlled with higher precision. be able to.

(Modification 2) Modification 2 will be described.
The optical multiplexing circuit 106 is used as a first circuit unit having a normal steep transmittance / wavelength characteristic or a second circuit unit having a transmittance / wavelength characteristic that is duller than the first circuit unit. You may comprise.

Hereinafter, a specific description will be given.

In the improved optical multiplexing circuit 106 shown in FIGS. 3 and 4, the transmittance / wavelength characteristics of the optical multiplexing circuit portion for inputting an optical signal for communication and the optical multiplexing circuit for inputting an input optical signal for inspection are shown. The description has been given of the case where the transmittance and wavelength characteristics of the circuit portion are the same characteristics. However, the transmittance and wavelength characteristics of the optical multiplexing circuit portion for inputting the input optical signal for inspection are described above. In this way, the leakage output corresponding to the deviation of the oscillation wavelength is increased by designing for the wavelength gap of 50 GHz, but the transmittance / wavelength characteristic of the optical multiplexing circuit portion for inputting the optical signal for communication is the normal wavelength gap of 100 GHz. And a configuration in which a larger optical multiplexing output can be obtained.

Further, if two types of optical multiplexing circuit portions having significantly different wavelength characteristics as shown in FIGS. 3 and 4 are formed as the same AWG optical multiplexing circuit pattern, there is waste on the circuit pattern. In this case, the two types of optical multiplexing circuit portions are formed as independent circuit patterns, and the two circuit patterns are combined to form an optical multiplexing circuit portion for inputting an optical signal for communication and an optical multiplexing portion for inputting an input optical signal for inspection. One improved optical multiplexing circuit having a wave circuit portion can be equivalently configured.

In this case, it is needless to say that an increase in the chip area due to the independent formation of the circuit patterns is minimized by drawing the circuit patterns so as not to impair the operation function. .

In the example of the improved optical multiplexing circuit shown in FIGS. 3 and 4, the case of the improved optical multiplexing circuit having twice the number of channels required for communication is shown. When the number of channels is four times, almost the same operation can be obtained, and the economics of the improved optical multiplexing circuit tend to worsen with the increase in the number of redundant channels. The number of input / output terminals for inspection other than the input / output terminals for communication can be increased, and the advantage that the degree of freedom for providing an inspection function is increased.

[Third Example] A third embodiment of the present invention will be described with reference to FIG. The description of the same parts as those in the above-described examples is omitted, and the same reference numerals are given.

FIG. 5 shows a configuration example of a WDM optical interface device.

The transmitting unit 1 has the same configuration as that shown in FIG.
It consists of the components 01 to 109.

[0116] The receiving unit 2 includes the component 113 shown in FIG.
To 115 are omitted, that is,
A downstream input terminal 111, an optical demultiplexing circuit 112, and a plurality of downstream output terminals 116 respectively corresponding to outputs of a plurality of wavelengths of the optical demultiplexing circuit 112 are connected in series in this order. .

The transmission of the signal output of the transmission unit 1, the monitoring, control and stabilization of the oscillation wavelength of each unit circuit of the electric / optical conversion circuit 104, and the reception of the signal input of the reception unit 2 are shown in FIG. It can be implemented in exactly the same way as the configuration.

The difference from FIG. 1 is that the output level at the downstream output terminal 115 is not sufficiently guaranteed.
By using the one-chip AWG optical multiplexing / demultiplexing circuit 117 as described in the above, the variation in characteristics due to insertion loss and wavelength can be sufficiently reduced, and the circuit can be omitted.

It is needless to say that an optical amplifier can be inserted between the downstream input terminal 111 and the optical demultiplexing circuit 112 to increase the signal amplitude if necessary.

[Fourth Example] A fourth embodiment of the present invention will be described with reference to FIG. The description of the same parts as those in the above-described examples is omitted, and the same reference numerals are given.

FIG. 6 shows a configuration example of a WDM optical interface device.

In the present embodiment, the same 10-level as that shown in FIG.
It has a transmitting unit 1 composed of components 1 to 109, and 111
Has a receiving portion 2 consisting of a component of -116, further by adding a low-frequency oscillation circuit 110, each unit circuit of the single-wavelength light source unit _{90 (λ 1, λ 2,} λ 3, ... correspond to the This is different from the first embodiment in that a low-frequency signal can be sequentially superimposed on each signal.

Further, the optical multiplexing circuit 106 of the present embodiment does not increase the number of channel waveguides as compared with the conventional optical multiplexing circuit. The difference lies in that it is configured as an improved optical multiplexing circuit in which the inspection output terminal 40 is derived from the wave path.

That is, the inspection output terminal 40, the optical / electrical conversion circuit 108, the identification control circuit 109, and the temperature control circuit 130 of each unit circuit of the electric / optical conversion circuit 104 are connected in series in this order. Together with the low frequency oscillation circuit 11
By adding 0, a control configuration is adopted such that a low-frequency signal can be sequentially superimposed on each signal of each unit circuit of the single-wavelength light source device 90.

More specifically, the present apparatus comprises a low-frequency oscillator 11
0, two inspection output terminals 40 provided in the optical multiplexing circuit 106, an optical / electrical conversion circuit 108, an identification control circuit 109, a low frequency oscillator 110 and each unit circuit of the single wavelength light source device 90. Are sequentially coupled, and the switch 141 sequentially connects the identification control circuit 109 and the temperature control circuit 130 of each unit circuit of the electric / optical conversion circuit 104 to constantly monitor the oscillation wavelength. It is controlled and stabilized.

Hereinafter, the operation will be described.

In FIG. 6, the wavelength multiplexed optical signal 4 is input from the input of the optical input signal 3 to the upstream input terminal 101 to the upstream output terminal 107 via the normal output terminal 30 of the optical multiplexing circuit 106.
The operation of the transmission unit 1 until the output of the wavelength division multiplexed signal and the wavelength multiplexed optical signal 5 received at the downstream input terminal 111 of the reception unit 2 are demultiplexed by the optical multiplexing circuit 112 and the optical output signal 6 is output to the downstream output terminal 116. The receiving operation described above is exactly the same as that described in FIG.

In this example, a leakage output of a level corresponding to the shift amount from the center value of the oscillation wavelength of each unit circuit of the electric / optical conversion circuit 104 is obtained from the inspection output terminal 40 of the optical multiplexing circuit 106, The electric / electrical conversion circuit 108 converts the electric signal into an electric signal, and the identification control circuit 109 outputs a control signal to the temperature control circuit 130 of each unit circuit of the electric / optical conversion circuit 104.

The shift direction from the center value of the oscillation wavelength depends on whether the leakage output from the inspection output terminal 40 located on the upper side is large or the leakage output from the inspection output terminal 40 located on the lower side is large. Since it can be determined, the identification control circuit 109
Thus, the control increase / decrease amount of the temperature control of each unit circuit of the electric / optical conversion circuit 104 can be output, whereby the oscillation wavelength of each unit circuit of the electric / optical conversion circuit 104 can be precisely controlled to be constant. Can be.

This control utilizes the advanced function of the AWG optical multiplexing / demultiplexing circuit 117. Although the details are omitted, the control for inspecting both sides of the normal output terminal 30 of the optical multiplexing circuit 106 is performed. A leak output corresponding to a leak component of the transmittance / wavelength characteristic of the optical demultiplexing circuit 107 appears at the output terminal 40,
Depending on whether the center value of the oscillation wavelength shifts to the high wavelength side or the low wavelength side, a leakage output amount corresponding to the shift amount can be obtained.

However, as the leakage output from the inspection output terminal 40 of the optical multiplexing circuit 106, an output corresponding to the shift amount from the center value of the oscillation wavelength of the specific unit circuit of the electrical / optical conversion circuit 104 appears. Instead, the electrical / optical conversion circuit 104
The leakage output is determined in such a manner that the amount of shift of the oscillation wavelength of each unit circuit from the center value is integrated.

Therefore, the transmission signal is sequentially transmitted to the transmission signals of each unit circuit of the single-wavelength light source 90 by the oscillation circuit 110 that oscillates a signal having a frequency sufficiently lower than the frequency of the transmission signal handled by the single-wavelength light source 90. The low-frequency signal is superimposed with almost no disturbance, and the inspection output terminal 4
The low-frequency signal component is extracted by extracting the low-frequency signal component from the leakage output obtained as an input to the discrimination control circuit 109 through the low-frequency signal.
And a leakage output corresponding to the shift amount from the center value of the oscillation wavelength can be obtained.
09, the control output of the temperature increase / decrease is limited to the unit circuit of the electric / optical conversion circuit 104 on which the low frequency signal is superimposed, and is output in a synchronized manner, so that the electric / optical conversion can be performed without interrupting the system operation. The shift of the oscillation wavelength of each unit circuit of the circuit 104 can be monitored, controlled, and stabilized, and the target unit circuit can be sequentially switched to perform monitoring, control, and stabilization.

Here, as a method of sequentially superimposing the low-frequency signal from the low-frequency oscillation circuit 110 on each unit circuit of the single-wavelength light source device 90, the output of the optical / electrical conversion circuit 102 is changed using the switch 140. , Amplification identification circuit 103, electric /
At any point before the input of the optical conversion circuit 104,
Switching control may be performed so that the low-frequency oscillation circuit 110 and each unit circuit of the single-wavelength light source device 90 are sequentially electrically coupled. In this case, the switching timing of each unit circuit can be performed in synchronization with the control signal output from the identification control circuit 109.

The control output of the discrimination control circuit 109 is transmitted to the temperature control circuit 13 of each unit circuit of the electric / optical conversion circuit 104.
In the method of sequentially supplying 0 to 0, the switching is performed in synchronization with the switching of the switch 140 using the switch 141, and the identification control circuit 109 and each unit circuit of the electric / optical conversion circuit 104 are sequentially connected. Switching control may be performed so as to make electrical connection.

As described above, the low-frequency oscillator 110,
Two inspection output terminals 4 provided in the optical multiplexing circuit 106
0, the optical / electrical conversion circuit 108, and the identification control circuit 109
A switch 140 for sequentially coupling the low-frequency oscillator 110 and each unit circuit of the single-wavelength light source device 90; and a temperature control circuit 130 of each unit circuit of the identification control circuit 109 and the electric / optical conversion circuit 104. Switch 14 for connection
1, a simpler and less expensive circuit configuration can be achieved without introducing an expensive wavelength measuring device, and the electrical / optical conversion circuit 1 can be implemented without interrupting system operation.
The shift of the oscillation wavelength of each of the unit circuits 04 can be monitored, controlled, and stabilized individually and sequentially.

[Fifth Example] A fifth embodiment of the present invention will be described with reference to FIG. The description of the same parts as those in the above-described examples is omitted, and the same reference numerals are given.

FIG. 7 shows a configuration example of a WDM optical interface device.

The transmitting section 1 is made up of 101 to 110 components similar to those shown in the apparatus of FIG.

[0139] The receiving unit 2 includes the component 113 shown in FIG.
To 115 are omitted, and the downstream input terminal 111
And an optical demultiplexing circuit 112 and a plurality of downstream output terminals 116 respectively corresponding to outputs of a plurality of wavelengths of the optical demultiplexing circuit 112 are connected in series in this order.

Hereinafter, the operation will be described.

The transmission of the signal output of the transmission section 1, the monitoring, control and stabilization of the oscillation wavelength of each unit circuit of the electric / optical conversion circuit 104, and the reception of the signal input of the reception section 2 are exactly the same as those shown in FIG. Can be implemented.

The difference from FIG. 6 is that the output level at the downstream output terminal 115 is not sufficiently guaranteed.
By using the one-chip AWG optical multiplexing / demultiplexing circuit 117 as described in the above, the variation in characteristics due to insertion loss and wavelength can be sufficiently reduced, and the circuit can be omitted.

If necessary, it is needless to say that an optical amplifier can be inserted between the lower input terminal 111 and the optical multiplexing circuit 112 to increase the signal amplitude.

[Sixth Example] A sixth embodiment of the present invention will be described. The description of the same parts as those in the above-described examples is omitted, and the same reference numerals are given.

In the WDM optical interface device shown in FIG. 6 and FIG.
Oscillates one low-frequency signal, and superimposes the low-frequency signal on each signal of each unit circuit of the single-wavelength light source device 90 in sequence, and performs identification control via the inspection output terminal of the optical multiplexing circuit 106. The extraction of the low-frequency signal component from the leakage output obtained as an input to the circuit 109 has been described.

As a result, a leakage output corresponding to the shift amount from the center value of the oscillation wavelength is obtained only for the unit circuit of the single-wavelength light source device 90 on which the low-frequency signal is superimposed.
Each unit of the electric / optical conversion circuit 104 is output by synchronizing and outputting the control output of the temperature increase / decrease from the identification control circuit 109 to the unit circuit of the electric / optical conversion circuit 104 on which the low frequency signal is superimposed. The shift of the oscillation wavelength of the circuit is sequentially monitored, controlled, and stabilized.

However, in addition to the above-described configuration, a plurality of unit circuits of the low-frequency oscillating circuit 110 are provided to oscillate a plurality of different low-frequency signals corresponding to each unit circuit of the single-wavelength light source device 90, and The low-frequency signals corresponding to the circuits are simultaneously superimposed, and the components of the plurality of low-frequency signals are simultaneously extracted from the leakage output obtained as an input to the discrimination control circuit 109 via the inspection output terminal 40 of the optical multiplexing circuit 106. Such a configuration may be adopted.

With such a configuration, a leakage output corresponding to the shift amount from the center value of the oscillation wavelength of each corresponding unit circuit of the single wavelength light source device on which each low frequency signal is superimposed is obtained, and identification is performed. The control output of temperature increase / decrease from each unit circuit of the control circuit 109 is simultaneously output in parallel to each unit circuit of the electric / optical conversion circuit 104 corresponding to each low frequency signal, and each unit of the electric / optical conversion circuit 104 is output. The shift of the oscillation wavelength of the circuit can be monitored, controlled and stabilized simultaneously and in parallel.

Further, in this configuration, the number of unit circuits of the oscillation circuit 110 and the type of low frequency to be oscillated are increased.
Although the number of unit circuits of the discrimination control circuit 109 tends to increase, monitoring, control, and stabilization of the oscillation wavelength of each unit circuit of the electric / optical conversion circuit 104 are not performed sequentially for each unit circuit, but are performed simultaneously. There is an advantage that it can be implemented for all unit circuits at all times.

In the apparatus described above, FIGS.
In the configuration shown in FIGS. 6 and 7, the optical multiplexing circuit 106
Although the number of channels and the number of input / output terminals are increased as an improved optical multiplexing circuit, the improved optical multiplexing circuit and the optical demultiplexing circuit 112 have a single chip AW having similar characteristics.
Although described as the G optical multiplexing / demultiplexing circuit 117, the optical demultiplexing circuit 112 used here requires a normal steep transmittance / wavelength characteristic, whereas the improved optical multiplexing circuit 106 uses a normal steep transmittance. AWG having a duller transmittance / wavelength characteristic in order to further increase the leakage output to the inspection output terminal 40 of the improved optical multiplexing circuit 106 without requiring the wavelength characteristic.
An optical multiplexing circuit is more preferable.

For example, the transmittance and wavelength characteristics of a normal one-chip AWG optical multiplexing / demultiplexing circuit 117 are such that the relative transmittance of the transmission region and the non-transmission region is about 30 dB over almost the entire wavelength region of the transmission region. , The transmittance sharply decreases at the boundary of the transmission region, and the leakage output at the boundary of the transmission region is about 5 dB.
Although the following steep transmittance and wavelength characteristics can be obtained,
Due to design changes such as increasing the size of the optical waveguide pattern of the G optical multiplexing circuit 106, the peak value of the relative transmittance in the transmission region and the non-transmission region is about 30 dB or more, but the transmittance gradually decreases to the boundary of the transmission region. And the leakage output at the boundary of the transmission area is 1
An AWG optical multiplexing circuit 106 having a gradual transmittance / wavelength characteristic of about 0 to 20 dB can be easily obtained.

Further, it is easy to manufacture the AWG optical multiplexing circuit 106 having the moderate transmittance and wavelength characteristics and the AWG optical demultiplexing circuit 112 having the normal steep transmittance and wavelength characteristics on one chip. Thus, the economy and the wavelength characteristic balance can be improved by the one-chip configuration described with reference to FIG.

Further, as a method of constructing an optical multiplexing circuit having the same effect as that of the optical multiplexing circuit 106 having a duller transmittance / wavelength characteristic, a normal AWG optical multiplexing / demultiplexing circuit 117 is used for input adjacent single-wave light. Wavelength gap of, for example, 100 GH
3 and FIG. 4 in which the design value of the wavelength gap of the input single-wave light of the improved optical multiplexing circuit is set to a half of 50 GHz, while a single-wavelength optical input of 100 GHz is input. The configuration method of the improved optical multiplexing circuit is effective. By setting the optical demultiplexing circuit to a wavelength gap of every 100 GHz, this gradual transmittance and
AWG optical multiplexing circuit 106 having wavelength characteristics and AWG optical demultiplexing circuit 112 having ordinary steep transmittance and wavelength characteristics
It can be easily made into chips.

[0154]

As described above, according to the present invention,
In the transmission unit, a plurality of optical signals are input, a single wavelength light source unit having a plurality of unit circuits that output a plurality of different wavelength optical signals, and a plurality of optical signals output from the single wavelength light source unit are input, Extracting an optical multiplexing unit that outputs the input plurality of optical signals as one wavelength-multiplexed optical signal multiplexed by multiplexing, and extracting a part of the plurality of optical signals output from the single-wavelength light source unit; A test signal extracting means for inputting the extracted signal as a test signal to the optical synthesizing section, detecting the test signal input to the optical multiplexing section, discriminating the state of the detected test signal, and Operation control means for outputting a control signal for controlling the operation of the unit, without introducing an expensive wavelength measuring device, without interrupting the system operation, and for each unit circuit in the single-wavelength light source unit. Individual oscillation wavelength shift Sequentially monitors, controls, can be stabilized, thereby, a simple circuit configuration, it is possible to perform highly accurate control of the oscillation wavelength.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an interface device that performs communication using WDM light according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an improved optical multiplexing / demultiplexing circuit according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing an optical path in an improved optical multiplexing circuit.

FIG. 4 is a block diagram showing transmission wavelength characteristics of an improved optical multiplexing circuit.

FIG. 5 is a block diagram illustrating a configuration of an interface device according to a third embodiment of the present invention.

FIG. 6 is a block diagram illustrating a configuration of an interface device according to a fourth embodiment of the present invention.

FIG. 7 is a block diagram illustrating a configuration of an interface device according to a fifth embodiment of the present invention.

FIG. 8 is a block diagram showing a first conventional example.

FIG. 9 is a block diagram showing a second conventional example.

FIG. 10 is a block diagram showing a third conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transmitting part 2 Receiving part 3 Optical input signal 4, 5 WDM optical signal 6 Optical output signal 7 Inspection signal 10 Input terminal 20 Inspection input terminal 30 Output terminal 31 Output waveguide 40 Inspection output terminal 41 Inspection output conductor Wave path 90 single wavelength light source device 91 single wavelength light receiving circuit 101 upstream input terminal 102 optical / electrical conversion circuit 103 amplification identification circuit 104 electrical / optical conversion circuit 105 optical switch 106 optical multiplexing circuit 107 upstream output terminal 108 optical / electrical conversion circuit 109 identification Control circuit 111 Down input terminal 112 Optical demultiplexing circuit 113 Optical / electrical conversion circuit 114 Amplification discrimination circuit 115 Electric / optical conversion circuit 116 Down output terminal 117 AWG optical multiplexing / demultiplexing circuit 130 Temperature adjusting circuit 140, 140 switch

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Koichi Fujisaki 1-1-12 Dogenzaka, Shibuya-ku, Tokyo NTT Electronics Corporation (72) Inventor Akimasa Kaneko 1-12-1 Dogenzaka, Shibuya-ku, Tokyo N Within Titi Electronics Co., Ltd. (72) Inventor Yoshihisa KAI 2-3-1 Otemachi, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation F-term (reference) 2H047 KA03 KA12 KB01 KB03 LA18 5K002 BA05 BA06 CA05 DA02 EA05 EA06 FA01 5K042 AA08 CA10 CA13 DA01 DA16 DA22 FA03 FA22 JA01 LA14

Claims (13)

[Claims] 1. A method of combining a plurality of optical signals to obtain one
An interface device comprising: a transmitting unit that outputs two wavelength multiplexed optical signals; and a receiving unit that receives and demultiplexes one wavelength multiplexed optical signal to output optical signals of a plurality of different wavelengths, wherein the transmitting unit A plurality of optical signals are input, a single wavelength light source unit having a plurality of unit circuits for outputting a plurality of different wavelength optical signals, and the plurality of optical signals output from the single wavelength light source unit are input, An optical multiplexing unit that outputs the input plurality of optical signals as one wavelength multiplexed optical signal by multiplexing, and extracts and extracts a part of the plurality of optical signals output from the single wavelength light source unit A test signal extracting means for inputting a signal to the optical multiplexing unit as a test signal; detecting the test signal input to the optical multiplexing unit; determining a state of the detected test signal; Movement of wavelength light source Interface device being characterized in that comprises an operation control means for outputting a control signal for controlling. 2. The optical multiplexing unit according to claim 1, wherein the optical multiplexing unit includes an output terminal for normal output for outputting the wavelength multiplexed optical signal, and an output terminal for inspection for outputting the inspection signal. Interface device. 3. The test signal extracting means includes an optical switch circuit connected between the single-wavelength light source unit and the optical multiplexing unit, and the optical multiplexing unit is directly connected to the single-wavelength light source unit. And an inspection input terminal connected via the optical switch circuit, wherein the optical multiplexing unit is connected to each of the unit circuits of the single wavelength light source unit via the input terminal. While inputting the plurality of optical signals, and inputting an inspection signal via the optical switch circuit and the inspection input terminal, and converting the input plurality of optical signals from the output terminal as the wavelength-multiplexed optical signal. 3. The interface device according to claim 1, wherein the interface device outputs the test signal from the test output terminal corresponding to each unit circuit of the single-wavelength light source unit. 4. The first inspection for inspecting whether or not each unit circuit of the single-wavelength light source unit is operating normally based on the detected inspection signal, wherein the first inspection is performed. A second inspection for inspecting the oscillation wavelength of the single-wavelength light source unit based on the inspection signal, or a third inspection including both the first inspection and the second inspection; A first output for outputting a control signal corresponding to the oscillation amplitude of each unit circuit of the single-wavelength light source unit based on the inspection result of the inspection, and a respective output of the single-wavelength light source unit based on the inspection result of the second inspection; A second output for outputting a control signal corresponding to the shift amount of the oscillation wavelength of the unit circuit, or a second output corresponding to the oscillation amplitude of each unit circuit of the single wavelength light source unit based on the inspection result of the third inspection. And the oscillation wavelength of each unit circuit of the single wavelength light source unit. Interface device according to any one of claims 1, characterized in that so as to stabilize by performing a third output for outputting a control signal corresponding to the shift amount 3. 5. The receiving unit, comprising: a downlink input terminal that receives the one wavelength-multiplexed optical signal;
An optical demultiplexing unit for demultiplexing the one wavelength-multiplexed optical signal and outputting optical signals of a plurality of different wavelengths; and a plurality of amplifying and discriminating and reproducing the demultiplexed optical signals for each wavelength. A first circuit unit including a single-wavelength light receiving unit and a downstream output terminal that outputs the reproduced optical signal, or includes the downstream input terminal, the optical demultiplexing unit, and the downstream output terminal. 5. The interface device according to claim 1, wherein the interface device is configured as a second circuit unit. 6. The optical multiplexing section includes a first circuit section having a normal steep transmittance / wavelength characteristic, or a first circuit section having a transmittance / wavelength characteristic duller than the first circuit section. The interface device according to any one of claims 1 to 5, wherein the interface device is configured as two circuit units. 7. The optical multiplexing unit according to claim 1, wherein the inspection output terminal is divided into two to obtain an inspection signal corresponding to a shift amount from a center wavelength. An interface device according to any one of the above. 8. The single-wavelength light source unit, wherein the optical multiplexing unit includes: an output terminal for normal output for outputting the wavelength multiplexed optical signal; and an output terminal for inspection adjacent to the output terminal for normal output. A leakage output corresponding to the shift amount of the oscillation wavelength of the light is detected as the inspection signal through the inspection output terminal, and the oscillation wavelength of the single-wavelength light source unit is monitored and stabilized based on the detected inspection signal. 2. The interface device according to claim 1, wherein the interface device is configured to perform the operation. 9. A circuit for extracting a leakage output corresponding to the shift amount of the oscillation wavelength, monitoring the oscillation wavelength of the single-wavelength light source section, and stabilizing the oscillation output, comprising: a low-frequency oscillation circuit; A switch for sequentially electrically coupling the low-frequency oscillation circuit and each unit circuit of the single-wavelength light source unit, and extracting the low-frequency component of the leak output obtained from the inspection output terminal, corresponding to the output level. An identification control circuit for obtaining a control output, a temperature control circuit for controlling the temperature of each unit circuit of the single-wavelength light source unit, and a switch for sequentially electrically coupling the identification control circuit and the temperature control circuit. The interface device according to claim 1 or 8, wherein 10. The operation control means is a circuit for extracting a leakage output corresponding to the shift amount of the oscillation wavelength, monitoring the oscillation wavelength of the single-wavelength light source unit, and stabilizing the oscillation output. A low-frequency oscillation circuit composed of a plurality of unit circuits, and the low-frequency oscillation circuit and the corresponding unit circuits of the single-wavelength light source unit are electrically coupled to each other to reduce the leakage output obtained from the inspection output terminal. Extracting a frequency component, an identification control circuit including a plurality of unit circuits that obtain a plurality of control outputs corresponding to the output levels of the respective low-frequency components, and a temperature control circuit of a unit circuit of the single-wavelength light source unit, 9. The interface device according to claim 1, wherein the identification control circuit is electrically coupled to a temperature control circuit of a corresponding unit circuit of the single wavelength light source unit. 11. The receiving unit, comprising: a downlink input terminal that receives the one wavelength-multiplexed optical signal;
An optical demultiplexing unit for demultiplexing the one wavelength-multiplexed optical signal and outputting optical signals of a plurality of different wavelengths; and a plurality of amplifying and discriminating and reproducing the demultiplexed optical signals for each wavelength. A first circuit unit including a single-wavelength light receiving unit and a downstream output terminal that outputs the reproduced optical signal, or includes the downstream input terminal, the optical demultiplexing unit, and the downstream output terminal. 11. The interface device according to claim 8, wherein the interface device is configured as a second circuit unit. 12. The optical multiplexing section, wherein the first circuit section has a normal steep transmittance / wavelength characteristic or the second circuit section has a transmittance / wavelength characteristic which is duller than the first circuit section. The interface device according to any one of claims 8 to 11, wherein the interface device is configured as two circuit units. 13. An optical multiplexing / demultiplexing unit in which the optical multiplexing unit of the transmitting unit and the optical demultiplexing unit of the receiving unit having normal steep characteristics are integrated into one chip. Item 13. The interface device according to any one of Items 1 to 12.