JP2000341214A - Optical transmission system and optical transmission method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical transmission system with a simplified configuration and enhanced reliability and to provide an optical transmission method. SOLUTION: The optical transmission system consists of a data line 10 consisting of n-sets of signal lines used to transmit a plurality of data #1-#n, optical transmitters 200-20n+m (n=1-n, m=0-m) that convert the data #1-#n sent through the data line 10 into optical signals, a data selector section 40 that is connected to the n-sets of the signal lines of the data line 10 and connected to the optical transmitters 200-20n+m via signal lines 300-30n+m, a digital signal processing unit 60 that is connected to the optical transmitters 200-20n+m via a control data transmission bus 50 and a control data reception bus 51, and optical fibers 700-70m+n, that transmit the optical signals converted by the optical transmitters 200-20n+m. The m-sets of the optical transmitters are used for spare transmitters.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an optical transmission system, and more particularly to an optical transmission system and an optical transmission method for performing an automatic avoidance operation when an optical transmitter fails or deteriorates.

[0002]

2. Description of the Related Art In a backbone optical transmission system, wavelength multiplex transmission (WDM) is used to dramatically increase the transmission capacity per optical fiber in order to increase the transmission capacity. With the rapid growth of the data communication market in recent years, the demand for increasing the transmission capacity is also rapidly increasing, and such a wavelength multiplexing transmission system responds to the need for increasing the transmission capacity by increasing the number of multiplexed wavelengths. In the backbone optical communication system, since the amount of data transmitted per unit time is extremely large and the importance is extremely high, high reliability is required for the entire system. In the case of wavelength division multiplexing transmission, since one optical transmitter is used for one wavelength, as the number of wavelength division multiplexing increases, the configuration of the whole system becomes more complicated, the failure rate increases, and the reliability of the whole system increases. It is generally lower.

In a conventional system, such a decrease in reliability of the entire system is prevented by providing a backup circuit as disclosed in Japanese Patent Publication No. 20578/1990.

[0004]

However, in the prior art, since it is necessary to provide a backup circuit different from the optical transmitter, as the number of multiplexed wavelengths increases, the scale of the backup circuit increases and the backup circuit becomes larger. There has been a problem that the system becomes complicated and the configuration of the system becomes complicated.

In the prior art, the optical transmitter itself detects a decrease in the output light level and outputs an alarm signal to the backup circuit, thereby switching to the backup circuit. When a failure occurs, the system cannot detect a decrease in the output light level or the interruption of the output light, and there is a problem that the reliability of the system is reduced.

The present invention has been made in view of such a problem, and an object thereof is to perform backup by using an optical transmitter having the same configuration, so that a backup circuit different from the optical transmitter is not required. In addition, since the optical transmitter is entirely controlled by the digital signal processing device, even if the optical transmitter itself fails, the system can detect a decrease in the output light level or a cutoff of the output light, and the system configuration can be reduced. An object of the present invention is to provide an optical transmission system and an optical transmission method that can be simplified and improve the reliability of the system.

[0007]

Means for Solving the Problems In order to solve the above problems, the present invention has the following constitution. The gist of the invention according to claim 1 is that a plurality of optical transmitters respectively connected to a plurality of signal lines convert data transmitted from the plurality of signal lines into optical signals of different wavelengths and perform wavelength multiplex transmission. An optical transmission device for performing, the connection switching means for switching the connection between the plurality of signal lines and the plurality of optical transmitters, failure deterioration detection means for detecting failure or deterioration of the plurality of optical transmitters, A first instruction signal for disconnecting the optical transmitter and the signal line, the failure or deterioration of which has been detected by the failure degradation detection means; and the signal line disconnected and the other optical transmitter. Switching control means for outputting a second instruction signal to be connected to the connection switching means. The gist of the invention according to claim 2 includes a spare optical transmitter having the same configuration as the plurality of optical transmitters, wherein the switching control unit is configured to connect the disconnected signal line to the spare optical transmitter. 2. The optical transmission device according to claim 1, wherein the second instruction signal for connecting to the optical transmitter is output to the connection switching unit. The gist of the invention according to claim 3 is that the switching control means includes:
An optical transmitter information table that describes a responsible wavelength that can be dealt with among the different wavelengths for each of the plurality of optical transmitters and control information for outputting the responsible wavelength, the switching control unit includes: The optical transmitter capable of handling the wavelength of the optical signal output by the optical transmitter that has detected a failure or deterioration by the failure deterioration detection unit with reference to the transmitter information table is specified, and the connection is disconnected. The second connecting the signal line and the specified optical transmitter.
3. An optical transmission apparatus according to claim 1, wherein said connection switching means outputs an instruction signal. The gist of the invention described in claim 4 is that, in the optical transmitter information table, the assigned wavelengths of the backup optical transmitter correspond to all of the different wavelengths.
The optical transmission device according to any one of the above. Claim 5
The gist of the invention described is that the optical transmitter information table stores the assigned wavelengths of the plurality of optical transmitters as two different wavelengths.
The optical transmission device according to any one of claims 1 to 4, wherein the optical transmission device corresponds to at least one. The gist of the invention according to claim 6 further includes a use state determining unit that determines a use state of the plurality of signal lines, and the switching control unit includes:
Referring to the optical transmitter information table and the determination result by the use state determining unit, the wavelength of the optical signal output by the optical transmitter that has detected a failure or deterioration by the failure deterioration detecting unit can be assigned. The optical transmitter according to any one of claims 1 to 5, wherein the optical transmitter is specified. According to another aspect of the present invention, a plurality of optical transmitters respectively connected to a plurality of signal lines convert data transmitted from the plurality of signal lines into optical signals having different wavelengths, respectively. An optical transmission method for performing transmission, detecting failure or deterioration of the optical transmitter,
Disconnecting the connection between the optical transmitter and the signal line that has detected the failure or deterioration, and connecting the disconnected signal line to another optical transmitter. Exist. The gist of claim 8 is as follows.
8. The optical transmission method according to claim 7, wherein the disconnected signal line is connected to a spare optical transmitter having the same configuration as the optical transmitter. The gist of the invention according to claim 9 is that, for each of the plurality of optical transmitters, optical transmitter information including a responsible wavelength that can be handled from the different wavelengths and control information for outputting the responsible wavelength is stored. Identifying the optical transmitter that can handle the wavelength of the optical signal output by the optical transmitter that has detected the failure or deterioration with reference to the stored optical transmitter information, and disconnected the connection. 9. The optical transmission method according to claim 7, wherein the signal line is connected to the specified optical transmitter. The gist of the invention described in claim 10 is that the assigned wavelength of the backup optical transmitter is stored as the optical transmitter information in association with all of the different wavelengths. 9 in the optical transmission method. The gist of the invention described in claim 11 is that the assigned wavelengths of the plurality of optical transmitters are stored as the optical transmitter information in association with two or more wavelengths among the different wavelengths. An optical transmission method according to any one of claims 7 to 9. The gist of the invention according to claim 12 is that the use status of the plurality of signal lines is determined and the failure or deterioration is detected with reference to the stored optical transmitter information and the determined use status. The optical transmission method according to any one of claims 7 to 11, wherein the optical transmitter that can handle the wavelength of the optical signal output from the transmitter is specified.

[0008]

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

(First Embodiment) FIG. 1 is a block diagram showing a configuration of an optical transmission system according to a first embodiment of the present invention, and FIG. 2 is a block diagram showing a configuration of the optical transmitter shown in FIG. FIG. 3 is a block diagram showing a configuration of the digital signal processing device shown in FIG.

In the first embodiment, a plurality of data # 1 to #n
A data line 10 composed of n signal lines for transmitting
Optical transmitters 201 to n + m (n = 1 to n, m = 0) for converting data # 1 to #n sent from the data line 10 into optical signals
To m), connected to n signal lines of the data line 10, and connected to the optical transmitters 201 to n + m and the signal lines 301 to n + m.
A data selector unit 40 connected through the optical transmission units 201 to n + m, a control data transmission bus 50, and a control data reception bus 51; And optical fibers 701 to n + m for transmitting the optical signals converted by the devices 201 to n + m. The optical signals on the optical fibers 701 to n + m are combined by a light combining circuit (not shown), collected into one or a plurality of optical fibers, and transmitted to a receiving station. The number of the optical transmitters 201 to n + m is greater than the number of the data lines 10 including the n signal lines, and the number of the optical transmitters 201 to n + m is not connected to the data lines 10 via the data selector unit 40. The transmitter is used as a backup, that is, as a backup when a failure or deterioration occurs in the n optical transmitters connected to the data line 10, and FIG. 1 shows an embodiment where m = 1. Show.

The optical transmitters 201 to n + m have the same configuration, and as shown in FIG.
0, the LD drive unit 220, the Peltier drive unit 230,
LD module 240 and a resistance-voltage conversion circuit (hereinafter, referred to as a
An R / V conversion circuit) 250, AD converters (hereinafter, referred to as ADCs) 2601, 2602, and a modulation unit 270.
The LD module 240 includes a thermistor (T
h) 241, a photodiode (PD) 242, a laser diode (LD) 243, and a Peltier element (T
EC: Thermo Electric Controller) 244.

The address / data decoder 210 is connected to the control data transmission bus 50, extracts only control data relating to its own optical transmitter from the control data transmission bus 50, and transmits the extracted control data to the laser diode 24.
APC data for performing automatic output control (hereinafter, referred to as APC: Auto Power Control) for controlling the output intensity of the laser diode 243 to be constant, and automatic temperature for controlling the temperature of the laser diode 243 to be constant. Control (hereinafter A
ATC data for performing TC (referred to as Auto Temperature Control), and A for controlling the timing of transmission from the ADCs 2601 and 2602 to the control data reception bus 51.
APC data is sorted into DC timing data and APC data is LD
The ATC data is transmitted to the driving unit 220, the ATC data is transmitted to the Peltier driving unit 230, and the ADC timing data is transmitted to the ADC 26.
01, 2602

The LD driver 220 receives the APC data from the address / data decoder 210 and receives the received AP data.
The amount of current supplied to the laser diode 243 is changed according to the C data.

The Peltier driver 230 receives ATC data from the address / data decoder 210 and changes the direction and amount of current supplied to the Peltier element 244 according to the received ATC data.

The thermistor 241 is a temperature detecting element that changes the resistance value according to the temperature, and is used to measure the temperature of the laser diode 243. The laser diode 243 has a characteristic that the intensity of the output laser light changes according to the amount of supplied current.
This element has a characteristic that the laser light oscillation wavelength changes depending on the temperature, and outputs continuous laser light. The continuous laser light having an intensity corresponding to the amount of current supplied from the LD driving unit 220 is output to the modulation unit 270.

The photodiode 242 receives a part of the laser light output from the laser diode 243, changes the current value according to the intensity of the laser light, and outputs the current value to the ADC 2602. I do.

The Peltier element 244 is an element for changing the oscillation wavelength of the laser diode 243. The direction of the supplied current changes between heating and cooling, and the amount of supplied current determines the degree of temperature change. The laser diode 243 is heated or cooled according to the direction and amount of current supplied from the Peltier drive unit 230.

The R-V conversion circuit 250 includes a thermistor 241
By converting a change in the resistance value of
The temperature change inside the D module 240 is extracted as a voltage change, and the converted voltage value is transmitted to the ADC 2601.

In the ADC 2601, the R / V conversion circuit 250
The ADC 2602 converts the voltage value received from the CCD into temperature data and converts the current value received from the photodiode 242, that is, the signal for monitoring the output power of the laser diode 243, into power data. The data is transmitted to the control data reception bus 51 while referring to the ADC timing data.

The modulation unit 270 converts data to be converted into an optical signal and sends it to the data line 1 via the signal lines 301 to n + m.
0, the optical signal is generated by blocking and transmitting the continuous laser light output from the laser diode 243 according to the received data.
Output to 1 to n + m.

As shown in FIG. 3, the digital signal processing device 60 includes a control data receiving unit 61, a storage unit 62, an optical transmitter control unit 63, a control data transmitting unit 64, and a control information table setting unit 65. Consists of

The control data receiving unit 61 receives the temperature data and the power data transmitted from the optical transmitters 201 to n + m via the control data receiving bus 51, and controls the optical transmitter control unit 6.
Output to 3.

The storage unit 62 includes a control state table 66,
An optical transmitter information table 67 is stored, and a control state table 66 stores an optical transmitter 201 in charge of data # 1 to #n.
.About.n + m, an identification code of the oscillation wavelength of the laser light, an APC reference value that defines the intensity of the laser light, and an ATC reference that defines the internal temperature of the LD module 240, that is, the temperature of the laser diode 243. The optical transmitter information table 67 includes an identification code of the oscillation wavelength of the laser light handled by each of the optical transmitters 201 to n + m, an APC reference value that defines the intensity of the laser light, and , LD module 240
6 is a table showing an internal temperature of the laser diode 243, that is, an ATC reference value that defines the temperature of the laser diode 243.

The optical transmitter control section 63 is provided with each optical transmitter 201
The intensity of the laser light output from the laser diode 243 for A to
In addition to the APC that controls the temperature of the laser diode 243, the internal temperature of the LD module 240, that is, the temperature of the laser diode 243 is controlled by the AT in the control state table 66.
ATC for controlling the reference value for C is performed. Specifically, the power data transmitted from each of the optical transmitters 201 to n + m is constantly monitored, and APC data for generating the value as an APC reference value is output to the control data transmitting unit 64. And each of the optical transmitters 201-n
The temperature data transmitted from + m is constantly monitored, and ATC data for generating the value as the ATC reference value is generated and output to the control data transmission unit 64.

Further, the optical transmitter control unit 63 controls each optical transmitter 2
The power data and the temperature data transmitted from 01 to n + m are constantly monitored, and when the power data and the temperature data deviate from the allowable ranges, it is determined that the optical transmitter has failed or deteriorated, and the light that has been determined to have failed or deteriorated An automatic avoidance operation is performed on the data in charge of the transmitter. Specifically, referring to the control state table 66 and the optical transmitter information table 67, the optical transmitter that is not in charge of the data # 1 to #n is specified, and the optical transmitter determined to have failed or deteriorated is specified. A connection instruction signal for switching the connection to the optical transmitter is output to the data selector unit 40.

The control data transmission section 64 outputs the APC data and ATC data generated by the optical transmitter control section 63 to the control data transmission bus 50 as control data.

The control information table setting section 65 includes a storage section 6
2 are rewritten in accordance with an instruction from an input device (not shown).

Next, the operation of this embodiment will be described with reference to FIGS.
This will be described in more detail based on

FIG. 4 is a system configuration diagram illustrating an example of an optical transmission system in which m = 5 and n = 4 in the optical transmission system shown in FIG. 1, and FIG. FIG. 6 is a diagram showing a wavelength identification code, and FIG.
FIG. 7 is a diagram showing contents described in a control state table in the example optical transmission system shown in FIG. 4, and FIG. 7 is a diagram showing contents described in an optical transmitter information table in the example optical transmission system shown in FIG. FIG. 9 is a diagram illustrating a state where switching is performed in accordance with a failure of the optical transmitter in the example of the optical transmission system illustrated in FIG. 4. FIG. 9 is a diagram illustrating a state in which the failure of the optical transmitter in the example of the optical transmission system illustrated in FIG. FIG. 4 is a diagram showing contents described in a control information table shown in FIG. 3 when switching is performed.

FIG. 4 shows the operation of the present embodiment.
As shown in FIG. 7, the data handled by the data line 10 are four data # 1 to # 4, and the optical transmitters are five of the optical transmitters 201 to 5.
The system configuration is used. This corresponds to the system configuration in which m = 1 and n = 4 in FIG. In each optical signal, data # 1 is transmitted as an optical signal of wavelength λ1, data # 2 is transmitted as an optical signal of wavelength λ2, data # 3 is transmitted as an optical signal of wavelength λ3, and data # 4 is transmitted as an optical signal of wavelength λ4. At the time of normal operation (the state in which the optical transmitters 202 to 5 operate normally without failure or deterioration), the oscillation wavelengths of the optical transmitters 202 to 5 are λ1, the optical transmitter 203 is λ2, The transmitter 204 is λ3, and the optical transmitter 205 is λ4. In addition, each optical transmitter 2
The unique identification codes 01 to 5 and the oscillation wavelength identification codes unique to the respective oscillation wavelengths λ1 to λ4 are set as shown in FIG.

In the control state table 66, as shown in FIG. 6, an identification code indicating each of the optical transmitters 202 to 5 assigned to the data # 1 to # 4 is described in the assigned optical transmitter column 81. In the identification code column 82, the optical transmitters 202 to 5
The identification codes indicating the oscillation wavelengths λ1 to λ4 of the optical transmitters 202 to 5 are written in the APC reference value column 83, respectively.
Reference values for APC that define the intensity of the laser light in the ATC reference column are described.
Reference numeral 4 describes an ATC reference value that defines the internal temperature of the LD module 240 of the optical transmitters 202 to 5, that is, the temperature of the laser diode 243.

As shown in FIG. 7, the optical transmitter information table 67 stores the optical transmitters 201 to 5 in the optical transmitter number column 85.
Is indicated, and the oscillation wavelength identification code column 8
2, an identification code indicating the oscillation wavelength λ1 to λ4 assigned to each of the optical transmitters 201 to 5 is described, and an APC reference value column 83 and an ATC reference value column 84 are described in an oscillation wavelength identification code column 82. A corresponding to the oscillation wavelength
The PC reference value and the ATC reference value are described. Note that the optical transmitter 201 is provided as a spare, and may be responsible for all the oscillation wavelengths λ1 to λ4.
A PC reference value and an ATC reference value are defined.

First, APC and ATC will be described. The digital signal processing device 60 performs APC and ATC control in the order indicated in the assigned optical transmitter column 81 of the control state table 66. First, the digital signal processing device 60 refers to the assigned optical transmitter column 81 of data # 1 in the control state table 66, and recognizes that the first control target is the optical transmitter 202. Next, the digital signal processor 60
Is connected to the optical transmitter 202 via the control data transmission bus 50.
A data output command is sent to the ADC 2601 in the. Then, the ADC 2601 in the optical transmitter 202 sends the temperature data to the digital signal processor 60 via the control data receiving bus 51. The digital signal processing device 60 determines the temperature data and the AT of the optical transmitter 202 in the control status table 66.
With reference to the C reference value 17D1h, ATC data as a control amount for making the temperature data and the ATC reference value 17D1h equal is generated. Then, the generated ATC data is output to the optical transmitter 202 via the control data transmission bus 50.

Next, the digital signal processor 60 controls the A in the optical transmitter 202 through the control data transmission bus 50.
A data output command is sent to DC2602. Then, the ADC 2602 in the optical transmitter 202 is connected to the control data receiving bus 51.
The power data is transmitted to the digital signal processing device 60 via the. The digital signal processor 60 refers to the power data and the APC reference value A5D1h of the optical transmitter 202 in the control state table 66, and determines the power data and A
APC data, which is a control amount for making the PC reference value A5D1h equal, is calculated. Then, it outputs to the optical transmitter 202 via the control data transmission bus 50.
When this series of processing is completed, the process shifts to the control of the next optical transmitter 203 shown in the responsible optical transmitter column 81 of the control state table 66. When the APC and ATC processes up to the last optical transmitter 205 described in the responsible optical transmitter column 81 are completed, the APC and ATC are also transmitted from the optical transmitter 202 described first in the responsible optical transmitter column 81. Start control processing.

Next, an automatic avoidance operation for switching the transmitter due to a failure or deterioration of the optical transmitter will be described.

The digital signal processor 60 constantly monitors the power data and the temperature data from each of the optical transmitters 202 to 205, and if the values deviate from the allowable range, determines that the optical transmitter is out of order or has failed. The operation shifts to the automatic avoidance operation described below.

When a failure of the optical transmitter 205 occurs, the optical transmitter control unit 63 of the digital signal processor 60, which constantly monitors power data and temperature data from each of the optical transmitters 202 to 205, transmits the optical transmission signal. Detecting the failure of the optical transmitter 205 by detecting that the value of the power data or the temperature data received from the transmitter 205 deviates from the allowable range,
Immediately, the data selector 40 outputs a connection instruction signal for stopping the input of the data # 4 to the optical transmitter 205. The data selector unit 40 receives the connection instruction signal, and
Block input of data # 4 to 05. Further, the digital signal processor 60 transmits APC data and ATC data for stopping the output of the LD driver 220 and the Peltier driver 230 in the optical transmitter 205 via the control data transmission bus 50. Next, the data # of the control state table 66
4 is rewritten to “1001” representing the optical transmitter 201, and the optical transmitter information table 67 is rewritten.
The wavelength λ4 assigned to the optical transmitter 205 from the optical transmitter 2
APC reference value A5C4 when output to 01
h and the ATC reference value 17C4h
The C reference field 83 and the ATC reference field 84 are rewritten to the APC reference value A5C4h and the ATC reference value 17C4h. FIG. 8 shows the contents of the control state table 66 after rewriting.

Next, the digital signal processor 60 uses the rewritten APC reference value A5C4h and the ATC reference value 17C4h to generate the AP of the optical transmitter 201.
Start C and ATC operation. Thereafter, the optical transmitter 20
When the temperature data and the power data of 1 are almost equal to the respective reference values and are stabilized, the digital signal processing device 60 sends the optical transmitter 201 to the data selector 40.
The data selector 40 outputs a connection instruction signal for flowing the data # 4, and connects the data line 10 related to the data # 4 and the signal line 301, and the transmission of the data # 4 is performed by the optical transmitter 201.
Will be resumed via FIG. 9 shows the optical transmission system after switching. As described above, according to the present embodiment, since the backup is performed by the optical transmitter having the same configuration, a backup circuit different from the optical transmitter is not required, and the optical transmitter is entirely used by the digital signal processing device. For control, even if the optical transmitter itself fails, the system can detect a decrease in the output light level or a break in the output light as a system, thereby simplifying the system configuration and improving the reliability of the system. This has the effect that it can be performed.

Further, since all the optical transmitters are controlled by one digital signal processor, the control parameters (APC reference value, ATC reference value) stored in the digital signal processor are controlled. Since the output power and output wavelength of all the optical transmitters can be changed only by changing, it is possible to correct the change in the wavelength of the laser light due to the deterioration of the LD module, for example, by a simple operation to the digital signal processing device. It works.

(Second Embodiment) FIG. 10 is a diagram showing the contents of the optical transmitter information table shown in FIG. 3 used in the second embodiment of the optical transmission system according to the present invention.

The second embodiment differs from the first embodiment in that
The same number of optical transmitters 201 as the number of signal lines of the data line 10
Nn are provided, the optical transmitter control unit 63 has a determination function of determining the data transmission status of the optical transmitters 2011n, and the description content of the optical transmitter information table 67 is different. The other configuration is the same as that of the first embodiment. The discriminating function of discriminating the data transmission status of the optical transmitters 201 to n in the optical transmitter control unit 63 is performed by n
Data lines 1 to #n, which detect the status of data # 1 to #n transmitted by the signal line, and receive data for a predetermined time.
The optical transmitters 201 to n connected to the signal line 0 are recognized as unused optical transmitters 201 to n, or by setting the unused optical transmitters 201 to n in advance to perform data transmission. Determine the situation.

In the optical transmitter information table 67, as shown in FIG. 10, an identification code indicating each of the optical transmitters 201 to n is described in an optical transmitter number column 85, and an oscillation wavelength identification code column 82
The oscillation wavelength λ1 assigned to each of the optical transmitters 201 to n.
The identification code indicating the oscillation wavelength up to two adjacent wavelengths which may be assigned together with the identification code indicating ~ λn is described.
In the C reference value column 84, an APC reference value and an ATC reference value corresponding to the oscillation wavelength described in the oscillation wavelength identification code column 82 are described.

When a failure occurs in any of the optical transmitters 201 to n, the optical transmitter control unit 63 of the digital signal processing device 60 determines the data transmission status of the optical transmitters 201 to n and the transmitter information table 67. The nearest unused optical transmitter (not transmitting data) in the optical transmitters 201 to n (the oscillation wavelength assigned to the failed optical transmitter is the oscillation wavelength identification code in the transmitter information table 67). The optical transmitters 201 to n described in the column 82 are identified, and an automatic avoidance operation for switching from the failed optical transmitter to the identified optical transmitter is performed. This eliminates the need to prepare a spare optical transmitter in advance (corresponding to m = 0 in the first embodiment), and realizes an automatic avoidance operation accompanying a failure or deterioration.

In the second embodiment, an identification code indicating up to two adjacent oscillation wavelengths, which are oscillation wavelengths that may be assigned, is described in the oscillation wavelength identification code column 82 of the transmitter information table 67. However, an identification code indicating the oscillation wavelength up to the next one or an identification code indicating all the oscillation wavelengths may be described.

Further, in the second embodiment, when a failure occurs in the optical transmitters 201 to n, when there is no unused optical transmitter as the nearest optical transmitter, a plurality of optical transmitters The automatic avoidance operation can be realized by switching the connection.

Next, in the optical transmitters 201 to n, the modulator integrated LD module 90 is used instead of the LD module 240.
An example of using is described.

FIG. 11 is a diagram showing an example in which a modulator-integrated LD module is used instead of the LD module shown in FIG.

A modulator driving circuit 91 for driving the modulator-integrated LD module 90 is provided between the data line 10 and the modulator-integrated LD module 90, and the other configuration is the same as that of the first embodiment.

It should be noted that the present invention is not limited to each of the above embodiments, and each embodiment can be appropriately modified within the scope of the technical idea of the present invention. Further, the number, position, shape, and the like of the constituent members are not limited to the above-described embodiment, but can be set to numbers, positions, shapes, and the like suitable for carrying out the present invention. In the drawings, the same components are denoted by the same reference numerals.

[0050]

According to the optical transmission system and the optical transmission method of the present invention, since the backup is performed by the optical transmitter having the same configuration, a backup circuit different from that of the optical transmitter is not required. Since the transmitter is controlled, even if the optical transmitter itself fails, the system can detect a decrease in the output light level or a break in the output light, simplifying the system configuration, and improving the reliability of the system. The effect that it can improve is produced.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a first embodiment of an optical transmission system according to the present invention.

FIG. 2 is a block diagram showing a configuration of the optical transmitter shown in FIG.

FIG. 3 is a block diagram showing a configuration of the digital signal processing device shown in FIG.

FIG. 4 is a system configuration diagram illustrating an example of an optical transmission system in which m = 5 and n = 4 in the optical transmission system illustrated in FIG. 1;

5 is a diagram showing an optical transmitter and an identification code of an oscillation wavelength shown in FIG. 4;

FIG. 6 is a diagram showing the contents of a control state table in the optical transmission system example shown in FIG. 4;

FIG. 7 is a diagram showing the content of an optical transmitter information table in the optical transmission system example shown in FIG. 4;

FIG. 8 is a diagram illustrating a state in which switching is performed in response to a failure of the optical transmitter in the example of the optical transmission system illustrated in FIG. 4;

9 is a diagram showing the contents of the control information table shown in FIG. 3 when switching is performed in response to a failure of the optical transmitter in the example of the optical transmission system shown in FIG. 4;

FIG. 10 is a diagram showing the description contents of an optical transmitter information table shown in FIG. 3 and used in a second embodiment of the optical transmission system according to the present invention.

11 is a diagram showing an example in which a modulator-integrated LD module is used instead of the LD module shown in FIG. 2;

[Explanation of symbols]

 # 1 to #n Data 10 Data line 201 to n + m Optical transmitter 210 Address / data decoder 220 LD driver 230 Peltier driver 240 LD module 241 Thermistor 242 Photodiode 243 Laser diode 244 Peltier element 250 R-V conversion circuit 2601, 2602 ADC 270 Modulation unit 301 to n + m signal line 40 Data selector unit 50 Control data transmission bus 51 Control data reception bus 60 Digital signal processing unit 61 Control data reception unit 62 Storage unit 63 Optical transmitter control unit 64 Control data Transmission unit 65 Control information table setting unit 66 Control state table 67 Optical transmitter information table 701 to n + m Optical fiber 81 Assigned optical transmitter column 82 Oscillation wavelength identification code column 83 APC reference value column 84 ATC reference value 85 optical transmitter number column 90 modulator integrated LD module 91 modulator drive circuit

Claims (12)

[Claims] 1. An optical transmission apparatus for performing wavelength division multiplexing transmission by converting data transmitted from a plurality of signal lines into optical signals having different wavelengths by a plurality of optical transmitters respectively connected to the plurality of signal lines. A connection switching unit that switches connection between the plurality of signal lines and the plurality of optical transmitters; a failure deterioration detection unit that detects a failure or deterioration of the plurality of optical transmitters; and the failure deterioration detection unit. A first instruction signal for disconnecting the optical transmitter and the signal line that has detected the failure or deterioration, and a second instruction for connecting the disconnected signal line and another optical transmitter. Switching control means for outputting a signal to the connection switching means. 2. A standby optical transmitter having the same configuration as the plurality of optical transmitters, wherein the switching control means connects the signal line disconnected and the standby optical transmitter. 2. The optical transmission device according to claim 1, wherein the second instruction signal to be output is output to the connection switching unit. 3. The switching control means stores an optical transmitter information table in which a wavelength assigned to the plurality of optical transmitters and a control information for outputting the wavelength assigned to the plurality of optical transmitters are described. The switching control unit refers to the optical transmitter information table, and detects the failure or the degradation by the failure degradation detection unit, and the light that can handle the wavelength of the optical signal output by the optical transmitter. 2. The connection switching unit according to claim 1, further comprising: causing the connection switching unit to output a second instruction signal for specifying a transmitter and connecting the disconnected signal line to the specified optical transmitter. 3. The optical transmission device according to 2. 4. The optical device according to claim 1, wherein the optical transmitter information table associates the assigned wavelengths of the backup optical transmitter with all of the different wavelengths. Transmission device. 5. The optical transmitter information table according to claim 1, wherein the assigned wavelengths of the plurality of optical transmitters correspond to two or more of the different wavelengths. Optical transmitter. 6. A switching device according to claim 1, further comprising: a use status determining unit configured to determine a use status of the plurality of signal lines, wherein the switching control unit refers to the optical transmitter information table and a determination result by the use status determination unit. 6. The optical transmitter according to claim 1, wherein the optical transmitter capable of handling the wavelength of the optical signal output from the optical transmitter that has detected a failure or deterioration by the failure deterioration detection unit is specified. The optical transmission device as described in the above. 7. An optical transmission method in which a plurality of optical transmitters respectively connected to a plurality of signal lines convert data sent from the plurality of signal lines into optical signals having different wavelengths to perform wavelength multiplex transmission. Detecting a failure or deterioration of the optical transmitter, disconnecting the optical transmitter and the signal line that has detected the failure or deterioration, and disconnecting the signal line and the other signal line. An optical transmission method comprising connecting to an optical transmitter. 8. The optical transmission method according to claim 7, wherein the disconnected signal line is connected to a standby optical transmitter having the same configuration as the optical transmitter. 9. An optical transmitter information comprising a responsible wavelength which can be dealt with among the different wavelengths for each of the plurality of optical transmitters and control information for outputting the responsible wavelength is stored. Identifying the optical transmitter that can take charge of the wavelength of the optical signal output by the optical transmitter that has detected the failure or deterioration with reference to the transmitter information, and identifying the signal line that disconnected the connection and the identification The optical transmission method according to claim 7, wherein the optical transmission method is connected to the optical transmitter. 10. The optical transmitter information according to claim 7, wherein the assigned wavelength of the backup optical transmitter is stored in correspondence with all of the different wavelengths. Optical transmission method. 11. The optical transmitter according to claim 7, wherein the assigned wavelengths of the plurality of optical transmitters are stored in association with two or more wavelengths among the different wavelengths as the optical transmitter information. The optical transmission method according to any one of the above. 12. The optical transmitter, which determines a use state of the plurality of signal lines, and refers to the stored optical transmitter information and the determined use state to detect the failure or the deterioration, and output the signal. 12. The optical transmission method according to claim 7, wherein the optical transmitter that can handle the wavelength of the optical signal is specified.