WO2002103937A1

WO2002103937A1 - Optical communication system and optical communication apparatus

Info

Publication number: WO2002103937A1
Application number: PCT/JP2001/005190
Authority: WO
Inventors: Eisaku Touma
Original assignee: Fujitsu Limited
Priority date: 2001-06-18
Filing date: 2001-06-18
Publication date: 2002-12-27

Abstract

Reliability and quality are improved by swiftly performing a process dealing with an occurrence of fault. Each optical secondary signal generating means (11) generates an optical secondary signal including the information of the condition of an optical main signal. Each multiplex transmitting means (12) transmits an optical multiplex signal obtained by multiplexing the optical main and secondary signals. Each separating means (22-1 to 22-n) separates the respective optical multiplex signal into the optical main and secondary signals. Operational condition determining means (23) determines, based on the condition information, whether the operational condition of the optical main signal received via a respective port (p1 to pn) is normal or not, and outputs an abnormality detection signal when an abnormality is detected in that operational condition. Optical level control means (24), when receiving the abnormality detection signal, reduces the optical level of the corresponding optical main signal. Wavelength multiplexing means (25), having channels to which the wavelengths of the respective input optical main signals have been assigned, performs a WDM wavelength multiplexing of the optical main signals inputted via the ports (P1 to Pn) associated with those channels.

Description

Description Optical communication system and optical communication device

The present invention relates to an optical communication system and an optical communication device, and more particularly, to an optical communication system and an optical communication device that perform optical communication control such as WDM (Wavelength Division Multiplex). Background art

Optical communication network technology is the core of the foundation of the information communication network, and further enhancement of services and wide area are desired, and its development is progressing rapidly toward the information society. On the other hand, WDM technology is widely used in recent optical communications. WDM is a system that multiplexes light of different wavelengths and simultaneously transmits multiple signals over a single optical fiber.

FIG. 10 is a diagram showing a schematic configuration of a conventional WDM transmitting apparatus. WDM transmitting apparatus 500 includes transbonders 501-1 to 501_n and transmitting section 510, and transmitting section 510 includes a wavelength multiplexing section 511 and an amplifying section 512.

The optical fiber cables C1 to Cn through which the optical signals output from the transbonders 501-1 to 501-n pass are connected to the input ports P1 to Pn of the transmission unit 510, respectively. —:! Connect the transmission section 510 to the transmission section 510.

The transbonders 501-1-1 to 501_n receive optical signals of different wavelengths λ1 to λn, respectively, transmitted from a TDM device (time division device) and the like, and transmit each optical signal for WDM transmission. The signal is converted into a narrow band optical signal and output. The wavelength multiplexing unit 511 performs wavelength multiplexing of a plurality of optical signals input from the input ports P1 to Pn to generate one WDM signal. Amplifying section 512 amplifies and outputs the WDM signal. Here, generally, the channel terminals CH1 to CHn of the wavelength multiplexing unit 511 are input terminals dedicated to each wavelength. The input ports Pl to Pn The input ports Pl to Pn are specified as dedicated ports for wavelengths λ1 to λη, respectively, because they are grouped with the channel terminals.

Therefore, for example, when the input port Ρ1 is a dedicated port of the wavelength λ1, the optical fiber cable C1 for outputting the optical signal of the wavelength λ1 must be connected to the input port Ρ1. When an optical fiber cable that transmits an optical signal having a wavelength of is connected, interference or the like occurs between channels inside the wavelength multiplexing unit 511 and normal operation is not performed.

On the other hand, in recent WDM systems, the number of wavelengths to be multiplexed has increased to more than 100 wavelengths, and the number of optical fiber cables connected to the system has increased accordingly.

Therefore, in such a situation, the possibility of misconnection of the optical fiber cable increases, and the number of times of malfunctions increases. However, in the above-described conventional technology, when the optical fiber cable is misconnected, There was a problem that no efficient measures were taken and the reliability and quality deteriorated.

In addition to incorrect connection of the optical fiber cable, poor connection of the optical fiber cable, deterioration of the cable itself, or transbonder 501- :! If there is a decrease in the output of 5 501 — η, the level of the optical signal of the corresponding wavelength will be lower than the levels of other optical signals to be multiplexed.

As a result, the OSNR (optical SZN) of the multiplexed signal of the WDM is reduced, and the quality is degraded. Did not take effective measures. Disclosure of the invention

SUMMARY OF THE INVENTION The present invention has been made in view of such a point, and an optical communication system that improves the reliability and quality by quickly performing a process corresponding to the occurrence of a failure related to an incorrect connection of an optical fiber cable or the like. The purpose is to provide a system.

Further, another object of the present invention is to provide an optical communication device which improves the reliability and quality by quickly performing a process corresponding to the occurrence of a failure related to an erroneous connection of an optical fiber cable or the like. is there. In the present invention, in order to solve the above problem, in an optical communication system 1 for performing WDM optical communication control as shown in FIG. 1, an optical sub signal generation for generating an optical sub signal including state information of an optical main signal is performed. Optical multiplexed signal control means 10a_l comprising means 11 and multiplex transmission means 12 for generating and transmitting an optical multiplexed signal obtained by multiplexing an optical main signal and an optical sub-signal. Optical multiplexing apparatus having optical transmission apparatus 10 having 〜10 a−n and ports P 1 PP n in which optical multiplex signals to be inputted are set corresponding to each wavelength of the optical main signal Signal receiving means 21, separating means 22-1 to 22 -n for separating an optical main signal and an optical sub-signal from an optical multiplexed signal, and state information indicated by the separated optical sub-signal, Control of whether the operation status of the optical main signal received via ports Pl to Pn is normal, If an error is detected, the operation state determination means 23 that outputs an abnormality detection signal and the optical level adjustment control of the optical main signal are performed. If an abnormality detection signal is received, the light of the corresponding optical main signal is output. Optical level control means 24 for performing level attenuation control, and the wavelength of the optical main signal to be input is set for each channel, and the optical main signal input through ports P1 to Pn corresponding to the channel There is provided an optical communication system 1 comprising: a wavelength multiplexing unit 25 configured to perform wavelength multiplexing of the WDM; and an optical wavelength multiplexing device 20 configured by:

Here, the optical sub-signal generating means 11 generates an optical sub-signal including state information of the optical main signal. The multiplexing transmission means 12 generates and transmits an optical multiplexed signal obtained by multiplexing the optical main signal and the optical sub-signal. The optical multiplexed signal receiving means 21 has ports P1 to Pn in which an optical multiplexed signal to be inputted is set corresponding to each wavelength of the optical main signal. The demultiplexing units 22_1 to 22-n separate the optical main signal and the optical sub-signal from the optical multiplexed signal. The operation state determination means 23, based on the state information indicated by the separated optical sub-signals, uses the port P :! Judgment control is performed to determine whether the operation state of the optical main signal received through Pn is normal, and when an abnormal state of the operation state is detected, an abnormality detection signal is output. The light level control means 24 performs light level adjustment control of the light main signal, and when receiving the abnormality detection signal, performs attenuation control of the light level of the corresponding light main signal. The wavelength multiplexing means 25 sets the wavelength of the optical main signal to be input for each channel, and performs WDM wavelength multiplexing of the optical main signal input through the ports P1 to Pn corresponding to the channel. . Further, as shown in FIG. 3, in the optical communication device 3 that performs optical communication control of the WDM, the ports Pl to in which the optical main signal to be input is set corresponding to each wavelength of the optical main signal. An optical main signal receiving means 31 having Pn; and a first opto-electrical converter for converting an optical level of the optical main signal into a first voltage which is a uniform voltage in a wavelength band used for WDM wavelength multiplexing. Means 41, second optical Z-electrical converting means 42 for converting the optical level of the optical main signal into a second voltage which is a voltage protruding only with respect to the wavelength of the optical main signal, A differential voltage calculating means 43 for calculating a differential voltage between the voltage and the second voltage; and, based on the first voltage and the differential voltage, as an operation state of the received optical main signal, an optical input state and a wavelength shift state. Operating state detecting means 4 for detecting the photoelectric conversion Switching controller 4 0 —:! ~ 40-n, optical level control means 34, which performs optical level adjustment control of the optical main signal, and performs optical level attenuation control for the optical main signal whose operation state is abnormal. The optical main signal monitoring means 33, which recognizes the operation state of the optical main signal and externally notifies the operation of the optical level control means 34 and the operation state, and the wavelength of the optical main signal to be inputted for each channel. A wavelength multiplexing means 35 for performing WDM wavelength multiplexing of optical main signals inputted through ports P1 to Pn corresponding to the set channels, and an optical communication device 3 comprising: Is done.

Here, the optical main signal receiving means 31 has ports Pl to Pn in which the optical main signal to be input is set, corresponding to each wavelength of the optical main signal. The first photoelectric conversion means 41 converts the optical level of the optical main signal into a first voltage which is a uniform voltage in a wavelength band used for WDM wavelength multiplexing. The second optical-Z electrical conversion means 42 converts the optical level of the optical main signal into a second voltage which is a voltage protruding only with respect to the wavelength of the optical main signal. The difference voltage calculation means 43 calculates a difference voltage between the first voltage and the second voltage. The operating state detecting means 44 detects an optical input state and a wavelength shift state as an operating state of the received optical main signal based on the first voltage and the differential voltage. The light level control means 34 performs light level adjustment control of the light main signal, and performs light level attenuation control for the light main signal whose operation state is abnormal. The optical main signal monitoring means 33 recognizes the operation state of the optical main signal based on the detection result, and performs operation control of the optical level control means 34 and external notification of the operation state. Wavelength multiplexing means 3 5 The wavelength of the optical main signal to be set is set for each channel, and WDM wavelength multiplexing of the optical main signal input through the ports P1 to Pn corresponding to the channel is performed.

The above and other objects, features and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings which illustrate preferred embodiments of the present invention. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a principle diagram of the optical communication system of the present invention.

FIG. 2 is a flowchart showing the operation of the optical communication system of the present invention.

FIG. 3 is a principle diagram of the optical communication device of the present invention.

FIG. 4 is a diagram showing a configuration of the optical / electrical conversion control unit.

FIG. 5 is a diagram showing a schematic image of the optical-Z electrical conversion of OZE.

FIG. 6 is a diagram illustrating the operation of the differential voltage detector.

FIG. 7 is a diagram for explaining the detection control of the out-of-wavelength state of the comparator. FIG. 8 is a diagram for explaining detection control of the out-of-wavelength state of the comparator. FIG. 9 is a diagram showing a logical table of detection results by the operation state detection means.

FIG. 10 is a diagram showing a schematic configuration of a conventional WDM transmitting apparatus. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating the principle of the optical communication system according to the present invention. The optical communication system 1 includes an optical transmission device 10 and an optical wavelength multiplexing device 20 and performs WDM optical communication control.

The optical transmission device 10 has a plurality of optical multiplexed signal control means 10a- :! to 10a-η corresponding to the wavelengths λ1 to λη of the optical main signal. The optical sub-signal generating means 11 generates an optical sub-signal including the status information of the optical main signal. The state information of the optical main signal included in the optical sub-signal includes the wavelength of the optical main signal, the current optical level (light intensity) state, and the wavelength stable state.

The wavelength stable state is 1-bit information indicating the light emission state when the light emitting section (not shown) of the optical main signal performs light emission control. The wavelength during the pull-in control from the start of light emission of the optical main signal fluctuates. Unstable state, or there is no wavelength fluctuation after the pull-in control ends. Indicates one of the steady state.

The multiplexing transmission means 12 multiplexes the optical main signal and the optical sub-signal including the status information of the optical main signal to generate an optical multiplexed signal, and transmits the multiplexed signal to the optical wavelength multiplexing apparatus 20. For example, the multiplexing transmission means 12 of the optical multiplexing signal control means 10a-1 controls the optical main signal m having a wavelength λ ΐ in normal operation and an optical level defined as Pwl. In this case, a wavelength λ 1, an optical level P wl, and an optical sub-signal s having state information of a current wavelength stable state (unstable and stable) are multiplexed with this optical main signal m to generate an optical multiplexed signal M. Send. In contrast to the optical wavelength multiplexing apparatus 20, the optical multiplexed signal receiving means 21 is provided for the ports P 1 to P 1 to which the optical multiplexed signal to be inputted is set corresponding to each wavelength of the optical main signal. n (ports P 1 to P n correspond to wavelengths λ 1 to λ n, respectively). Therefore, for example, the port P1 is a dedicated port to which the optical multiplexed signal M in which the optical main signal m of the wavelength λ1 is multiplexed is input. Other ports are also dedicated connection ports for each wavelength.

Then, when the optical transmitting apparatus 10 and the optical wavelength multiplexing apparatus 20 are connected, the optical multiplexing signal control means 10 a— :! .About.10a-n and ports P1-Pn of the optical multiplexed signal receiving means 21 are connected through optical fiber cables C1-Cn. The optical multiplexed signals transmitted from the optical multiplexed signal control means 10a_1 to 10a-n are input to the ports Pl to Pn, respectively.

The separating means 22-1 to 22_n separate the optical main signal and the optical sub-signal from the optical multiplexed signal. The separated optical main signal is transmitted to the optical level control means 24, and the optical sub signal is transmitted to the operation state determination means 23.

The operating state determining means 23 controls the determining whether the operating state of the optical main signal received via the ports P1 to Pn is normal based on the state information indicated by the separated optical sub-signal. Do. Then, when an abnormal state of the operation state is detected, an abnormal state detection signal for the corresponding optical main signal is output. In the operation state determining means 23, information on the normal operation state of each of the optical main signals received via the ports P1 to Pn is set in advance.

In addition, the operation state determination means 23 performs at least one determination control for the optical main signal, such as a wavelength shift state, an optical level state, and a wavelength stable state related to port matching. U. Judgment control of out-of-wavelength state related to port matching corresponds to detection control of misconnection of optical fiber cable, and judgment control of optical level state is control of detection of improper fitting of optical fiber cable, etc. Corresponds to. The determination control of the wavelength stable state corresponds to the detection control of whether or not the light emitting operation of the optical main signal is in the warm-up state. The external notification means 26 notifies the operation state of each optical main signal recognized by the operation state determination means 23 to the outside through a maintenance terminal or the like (performs display control on the maintenance terminal). The light level control means 24 performs light level adjustment control of the light main signal. When an abnormality detection signal is received, attenuation control of the optical level of the optical main signal determined to be abnormal is performed. The light level control means 24 is composed of, for example, a variable attenuator (VAT) using the magneto-optical effect.

The wavelength multiplexing means 25 sets the wavelength of the optical main signal to be input for each of the channels CH1 to CHn, and outputs the optical signals input through the ports P1 to Pn corresponding to the channels CH1 to CHn. Performs WDM wavelength multiplexing of the main signal.

That is, the terminals of the channels C H1 to C Hn of the wavelength multiplexing means 25 are input terminals dedicated to each wavelength corresponding to the wavelengths λ 1 to λ η. Then, the optical main signals input through the ports Ρ 1 to Ρ η are respectively input through the corresponding channel terminals C Η 1 to C η η, and the wavelength multiplexing means 25 performs WDM wavelength multiplexing control. It is.

Therefore, in order for the wavelength multiplexing means 25 to perform the wavelength multiplexing control correctly, an optical main signal having the same wavelength as the wavelength allocated to the channels CH1 to CHn must be input.

Here, for example, an optical multiplexed signal having an optical main signal of wavelength λ1 is transmitted from the optical transmitter 10 through the optical fiber cable C1, and an optical multiplexed signal having an optical main signal of wavelength λ2 is transmitted through the optical fiber cable C2. It is assumed that a multiplex signal is transmitted. It is also assumed that ports # 1 to # 3 of the optical wavelength multiplexing apparatus 20 are input ports corresponding to wavelengths λ1 to λ3, respectively. Then, as a normal cable connection state, the optical fiber cable C1 must be connected to the port # 1, and the optical fiber cable C2 must be connected to the port # 2.

Here, the optical fiber cable C 2 has a wavelength λ 3 Assume that it is connected to the corresponding port P3. Then, a transmission error occurs in the wavelength multiplexing control.However, in the past, since there was no function to detect such a wavelength shift state related to port consistency, the system was not affected by the transmission error. Was operating.

FIG. 2 is a flowchart showing the operation of the optical communication system 1 of the present invention. An example will be described in which the cable is connected incorrectly as described above.

[S1] The optical multiplexing signal control means 10a-1 of the optical transmitting apparatus 10 multiplexes the optical sub-signal indicating that the wavelength of the optical main signal is λ1 into the optical main signal to perform optical multiplexing. It generates a coded signal and outputs it through the optical fiber cable C1.

Similarly, the optical multiplexed signal control means 10a-2 multiplexes the optical sub-signal indicating that the wavelength of the optical main signal is λ2 into the optical main signal to generate an optical multiplexed signal, Output through optical fiber cable C2.

[S 2] The demultiplexing means 22-1 demultiplexes the optical main signal and the optical sub-signal from the optical multiplexed signal from the port P 1. The separating means 22-3 separates the optical main signal and the optical sub-signal from the optical multiplexed signal from the port P3.

[S 3] The operation state determination means 23 is received via the ports P 1 and P 3 based on the state information indicated by the optical sub-signal transmitted from the demultiplexing means 22-1 and 22-3. Judgment control is performed to determine whether the operation state of the optical main signal is normal.

Here, the optical main signal of wavelength λ 3 must be originally input from port P 3, but the operation state determining means 23 recognizes that the optical main signal of wavelength 2 is input, and光 Outputs an abnormality detection signal assuming that the optical main signal input through 3 is in an abnormal state.

[S4] The optical level control means 24 receives the abnormality detection signal and controls the attenuation of the optical main signal transmitted from the separation means 22-3 corresponding to the port P3. That is, the optical main signal output to the channel CH 3 of the wavelength multiplexing means 25 is subjected to maximum attenuation control, and the input to the wavelength multiplexing means 25 is shut down. As a result, it is possible to suppress the adverse effect of the wavelength multiplexing means 25 on other channels.

Note that the optical main signal transmitted from the separation means 22-1 corresponding to port P1 is On the other hand, normal light level control is performed.

[S5] The external notification means 26 acquires the operation state of the optical main signal from the operation state determination means 23, and that the optical main signal of the wavelength λ2 is input from the port P3 (optical fiber To the outside.

As described above, in the optical communication system 1 of the present invention, the optical sub-signal multiplexed on the optical main signal is used to determine whether or not the operation state of the optical main signal is normal. In addition, the optical level of the corresponding optical main signal is controlled to be attenuated, and an external failure is notified.

As a result, it becomes possible to quickly perform a process corresponding to the occurrence of a failure related to an erroneous connection of an optical fiber cable or the like. Also, in the above example, detection of the out-of-wavelength state related to port matching was described, but the same detection control is performed in the optical level state and the wavelength stable state.

That is, the operation state determining means 23 determines whether the optical level of the optical main signal input through the ports Ρ1 to Ρη is normal, and if there is an optical main signal with an abnormal optical level, The optical level control means 24 performs attenuation control and shuts down the input of the corresponding optical main signal to the wavelength multiplexing means 25. Alternatively, the operation state determination means 23 determines whether or not the wavelength stable state of the optical main signal input through ports Ρ 1 to Ρ η is normal. If the wavelength stable state is unstable, the optical level Attenuation control is performed by the control means 24, and the input of the corresponding optical main signal to the wavelength multiplexing means 25 is reduced.

Note that, in the optical communication system 1 of the present invention, the optical multiplexed signal control means 10a- :! to 10a-n can be installed inside the above-described transbonder or TDM device, for example. it can.

In addition, the optical wavelength band of the optical main signal usually has a wavelength around 1550 nm. For this reason, an optical wavelength band of about 130 nm is selected for the optical sub-signal as a wavelength that can be easily separated from the optical main signal.

Next, the optical communication device of the present invention will be described. FIG. 3 is a diagram illustrating the principle of the optical communication device according to the present invention. The optical communication device 3 performs optical communication control of WDM.

The optical main signal receiving means 31 is an optical main signal to be inputted corresponding to each wavelength of the optical main signal. It has ports Pl to Pn to which signals are set. Optical fiber cables C1 to Cn are connected to the ports P1 to Pn, and optical main signals of wavelengths λ :! to λη are input. The optical main signal input through the ports Ρ 1 to Ρ η is transmitted to the optical level control means 34 and the optical / electrical conversion control units 40 -1 to 40 _ installed in the ports Ρ 1 to η η. to η, branched by force bra. Photoelectric conversion controller 4 0—:! The first opto-electrical conversion means 41 converts the optical level of the optical main signal into a uniform voltage (flat voltage) in the wavelength band used for WDM wavelength multiplexing. Convert to 1 voltage. The second photoelectric converter 42 converts the optical level of the optical main signal into a second voltage that is a voltage protruding only with respect to the wavelength of the optical main signal.

The difference voltage calculation means 43 calculates a difference voltage between the first voltage and the second voltage. The operating state detecting means 44 detects an optical input state and a wavelength shift state as an operating state of the received optical main signal based on the first voltage and the differential voltage. The details of the photoelectric conversion control unit 40— :! to 40—η (collectively referred to as photoelectric conversion control unit 40) will be described later in detail.

The light level control means 34 performs light level adjustment control of the light main signal, and performs light level attenuation control on the light main signal whose operation state is abnormal. The optical main signal monitoring means 33 recognizes the operation state of the optical main signal based on the detection result of the operation state detection means 44 and performs operation control of the light level control means 34 and external notification of the operation state.

The wavelength multiplexing means 35 sets the wavelength of the optical main signal to be input for each channel, and performs WDM wavelength multiplexing of the optical main signal input through the ports Ρ1 to ηη corresponding to the channel. .

Next, the optical / electrical conversion controller 40 will be described. FIG. 4 is a diagram showing a configuration of the photoelectric conversion control unit 40. ΟΖΕ 4 1a is the first light-to-electricity conversion means 41, band-pass filter 4 2b and OZE 42 2a is the second light-to-electricity conversion means 42, differential voltage detector 43a is the differential voltage The calculating means 43, the comparators 44a and 44b, and the AND element 44c correspond to the operation state detecting means 44.

Here, the optical main signal sent from the port P of the optical main signal receiving means 31 is split into two by the power controller CP 1 and sent to the optical level control means 34 and the photoelectric conversion control section 40. Sent. In addition, the optical main signal is split into two by the power bra CP 2 and OZE 4 1 The signal is sent to the a side and the band pass filter 4 2 b side.

One optical main signal split by the power coupler CP 2 is subjected to optical Z-electric conversion at the received optical level versus output voltage by the OZE 41 a, which is uniform in the wavelength band used for WDM wavelength multiplexing. Is done. The wavelength of the other optical main signal is selected by a bandpass filter 42b composed of a dielectric film or the like, and then the photoelectric conversion is performed by OZE 42a. Therefore, photoelectric conversion with high conversion efficiency is performed only for the selected wavelength.

The bandpass filter 42b performs filtering corresponding to the wavelength of the optical main signal of each port. For example, the band-pass filter 42b in the optical-electrical conversion control unit 40-1, which is installed at the port P1 that receives the optical main signal of the wavelength λ1, performs the filtering of the wavelength λ1.

FIG. 5 is a diagram showing a schematic image obtained by photoelectric conversion of 、 41a and 242b. The vertical axis is voltage, and the horizontal axis is wavelength. The optical main signal converted by the OZE 41a has flat voltage characteristics. The optical main signal converted by the OZE 42a has a prominent voltage characteristic only for the selected wavelength λ0.

FIG. 6 is a diagram showing the operation of the differential voltage detector 43a. The difference voltage detector 43a obtains a difference between the output voltage Va from the OZE 41a and the output voltage Vb from the OZE 42a, and outputs a difference voltage Vc. The differential voltage Vc has a waveform as shown in the figure.

Next, the comparators 44a and 44b will be described. The comparator 44a compares the output voltage Va from the OZE 41a with the reference voltage V1. The comparator 44a detects a light input state. If the reference voltage V 1 <the output voltage V a, it means that the optical main signal is being input from the corresponding port, and the output of the comparator 44 a outputs “H”. If the reference voltage VI> the output voltage Va, the optical main signal is not input from the corresponding port, and the output of the comparator 44a outputs "L". On the other hand, the comparator 44b compares the difference voltage Vc for each wavelength with the reference voltage V2 to detect a wavelength shift state. FIGS. 7 and 8 are diagrams for explaining detection control of the comparator 44b in the out-of-wavelength state.

The differential voltages Vcl to Vcn of the optical main signals of wavelengths λ1 to λn are as shown in FIG. It takes shape. Then, each of the comparators 44 b in the photoelectric conversion control section 40-1 to 40-n has the position of the wavelength to be detected by itself for the waveform of the differential voltage Vc. Then, the wavelength deviation is detected based on whether or not the difference voltage Vc is lower than the reference voltage V2.

Here, with reference to FIG. 8, consider a comparator 44b that detects a wavelength shift of the optical main signal having the wavelength λ1. Since the wavelength to be detected by itself is λ1, the comparator 44b determines whether the difference voltage Vc1 is lower than the reference voltage V2 at the position of the wavelength λ1. If the difference voltage Vc1 at the position of the wavelength λ1 is lower than the reference voltage V2 (reference voltage V2> difference voltage Vc1), the optical main signal of the wavelength λ1 is correctly input from the corresponding port. You can recognize that you are being empowered.

If the difference voltage Vc1 at the position of the wavelength λ1 does not fall below the reference voltage V2 (reference voltage V2 <voltage Vc1), the optical main signal of the wavelength λιη other than the wavelength λ1 is input. Therefore, it can be determined that the optical fiber cable is incorrectly connected. By such a comparison control, the comparator 44b outputs "H" when the wavelengths match, and outputs "L" when the wavelengths are off.

As described above, each of the comparators 44 b inside the photoelectric conversion control units 40 — 1 to 40 — n installed for each port uses the differential voltage V c and the reference voltage V c at each wavelength position. Compare with 2 to detect the wavelength shift state.

FIG. 9 is a diagram showing a logical table of the detection results of the operation state detection means 44. The logic of the operating state (optical input state, wavelength shift state) of the optical main signal for points A, B, and C shown in Fig. 4 is shown.

These pieces of logical information are transmitted to the optical main signal monitoring means 33, and when there is an abnormal port, the level of the optical main signal from that port is attenuated and input to the wavelength multiplexing means 35. The optical level control means 34 is controlled so as to shut down, and an external notification is performed.

As described above, the optical communication system 1 and the optical communication device 3 of the present invention can quickly detect a failure caused by an erroneous connection of an optical fiber cable or the like due to an increase in the number of wavelength multiplexing. Becomes possible. In addition, the optical level of the erroneously input optical main signal is attenuated, and the input to the wavelength multiplexing means is reduced. Therefore, it is possible to reduce the adverse effects on the channels of other wavelengths.

In the above description, the optical communication control of the WDM has been described. However, the present invention can be applied to other optical communication control systems other than the WDM. On the other hand, it is possible to quickly detect a failure due to an incorrect connection of an optical fiber cable.

As described above, the optical communication system of the present invention performs control to determine whether or not the operation state of the optical main signal is normal based on the optical sub-signal including the state information of the optical main signal. In such a case, the optical level of the corresponding optical main signal is controlled to be attenuated. As a result, it is possible to quickly perform a process corresponding to the occurrence of a failure related to an erroneous connection of an optical fiber cable, and thus to improve reliability and quality. Further, the optical communication device of the present invention makes the optical level of the optical main signal protrude only with respect to the first voltage which is uniform in the wavelength band used for WDM wavelength multiplexing and the wavelength of the optical main signal. Based on the difference voltage and the first voltage, detects the optical input state and the wavelength deviation state of the optical main signal, and responds when an abnormality is recognized. The optical level of the optical main signal is attenuated. As a result, it is possible to quickly perform a process corresponding to the occurrence of a failure related to an erroneous connection of an optical fiber cable or the like, thereby improving reliability and quality.

The above merely illustrates the principles of the invention. In addition, many modifications and changes will be apparent to those skilled in the art and the present invention is not limited to the exact configuration and application shown and described above, but all corresponding variations and equivalents. Is deemed to be within the scope of the present invention by the appended claims and their equivalents.

Claims

The scope of the claims

1. In an optical communication system that performs WDM optical communication control,

Optical sub-signal generation means for generating an optical sub-signal including state information of the optical main signal; multiplex transmission means for generating and transmitting an optical multiplexed signal obtained by multiplexing the optical main signal and the optical sub-signal; An optical transmission device having an optical multiplexed signal control unit composed of:

An optical multiplexed signal receiving unit having a port in which the optical multiplexed signal to be inputted is set corresponding to each wavelength of the optical main signal; Separating means for separating the optical sub-signal from the optical sub-signal; and, based on the status information indicated by the separated optical sub-signal, whether the operation state of the optical main signal received via the port is normal or not. When an abnormal state of the operation state is detected, an operation state determination unit that outputs an abnormality detection signal, and a light level adjustment control of the optical main signal is performed, and the abnormality detection signal is received. In this case, the optical level control means for controlling the attenuation of the optical level of the corresponding optical main signal, and the wavelength of the optical main signal to be input is set for each channel, and is input through the port corresponding to the channel. Said said Wavelength multiplexing means for performing wavelength multiplexing WD M of the main signal, and configured optical wavelength multiplexer from

An optical communication system comprising:

2. The operation state determining means performs at least one of the wavelength shift state, the optical level state, and the wavelength stable state related to the matching of the port with respect to the optical main signal. Item 1. The optical communication system according to Item 1.

3. The optical communication system according to claim 1, further comprising external notification means for notifying the operation state to the outside.

4. In an optical transmission device that performs optical transmission control,

Optical sub-signal generating means for generating an optical sub-signal including state information of the optical main signal during normal operation;

Multiplex transmission means for generating and transmitting an optical multiplexed signal obtained by multiplexing the optical main signal and the optical sub-signal,

An optical transmission device comprising:

5. In an optical wavelength multiplexing device that performs WDM wavelength multiplexing control,

The optical multiplexed signal, in which the optical main signal and the optical sub-signal including the status information of the optical main signal, are multiplexed. The light to be input corresponding to each wavelength of the optical main signal. Optical multiplexed signal receiving means having a port where a multiplexed signal is set,

Separating means for separating the optical main signal and the optical sub-signal from the optical multiplexed signal; and the light received via the port based on the state information indicated by the separated optical sub-signal. An operation state determination unit that performs determination control as to whether or not the operation state of the main signal is normal, and outputs an abnormality detection signal when an abnormal state of the operation state is detected.

Light level control means for performing light level adjustment control of the light main signal, and, when receiving the abnormality detection signal, performing attenuation control of light level of the corresponding light main signal; and Wavelength multiplexing means for setting a wavelength of a signal for each channel and performing WDM wavelength multiplexing of the optical main signal input through the port corresponding to the channel;

An optical wavelength multiplexing device comprising:

6. The operation state determination means performs at least one of the wavelength shift state, the optical level state, and the wavelength stable state related to the matching of the port with respect to the optical main signal. Item 6. The optical wavelength multiplexing device according to Item 5.

7. The optical wavelength multiplexing apparatus according to claim 5, further comprising external notification means for notifying the operation state to the outside.

8. In an optical communication device that performs optical communication control of WDM,

Optical main signal receiving means having a port in which the optical main signal to be inputted is set, corresponding to each wavelength of the optical main signal;

First photoelectric conversion means for converting an optical level of the optical main signal into a first voltage which is a uniform voltage in a wavelength band used for WDM wavelength multiplexing; and A second photoelectric conversion means for converting into a second voltage which is a voltage protruding only with respect to the wavelength of the optical main signal, and calculating a difference voltage between the first voltage and the second voltage Based on the first voltage and the difference voltage, the operation state of the received optical main signal, the light input state and the wavelength are shifted. Operating state detecting means for detecting a state,

Light level control means for performing light level adjustment control of the light main signal, and performing light level attenuation control on the light main signal whose operation state is abnormal.

An optical main signal monitoring unit that recognizes the operation state of the optical main signal based on the detection result, and performs operation control of the optical level control unit and external notification of the operation state;

Wavelength multiplexing means for setting the wavelength of the optical main signal to be input for each channel, and performing wavelength multiplexing of WDM of the optical main signal input through the port corresponding to the channel;

An optical communication device comprising:

9. In an optical communication system that performs optical communication control,

An optical multiplexed signal receiving unit having a port in which the optical multiplexed signal to be inputted is set corresponding to each wavelength of the optical main signal; Separating means for separating the optical sub-signal from the optical sub-signal; and, based on the status information indicated by the separated optical sub-signal, whether the operation state of the optical main signal received via the port is normal or not. When an abnormal state of the operation state is detected, an operation state determination unit that outputs an abnormality detection signal, and a light level adjustment control of the optical main signal is performed, and the abnormality detection signal is received. In this case, an optical communication control device comprising: an optical level control means for performing attenuation control of the optical level of the corresponding optical main signal; and

An optical communication system comprising:

10. The operation state determination means performs at least one of the wavelength shift state, the optical level state, and the wavelength stable state related to the matching of the port with respect to the optical main signal. 9. The optical communication system according to 9.

11. The optical communication system according to claim 9, further comprising external notification means for notifying the operation state to the outside.

1 2. In an optical communication device that performs optical communication control,

First optical Z-electrical conversion means for converting the optical level of the optical main signal into a first voltage that is a flat voltage; and projecting the optical level of the optical main signal only with respect to the wavelength of the optical main signal. A second optical Z-electric conversion unit that converts the voltage into a second voltage that is the applied voltage; a difference voltage calculation unit that calculates a difference voltage between the first voltage and the second voltage; Operating state detecting means for detecting an optical input state and an out-of-wavelength state as an operating state of the received optical main signal based on a voltage and the differential voltage, and installed for each of the ports. Photoelectric conversion control unit,

Light level control means for performing light level adjustment control of the light main signal, and performing light level attenuation control for the light main signal whose operation state is abnormal.

An optical main signal monitoring unit that recognizes the operation state of the optical main signal based on a detection result, and performs operation control of the optical level control unit and external notification of the operation state;

An optical communication device comprising: