JP2012129644A - Optical transmission system, receiver, control method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical transmission system that can detect the disagreement of transmission/reception wavelengths, and prevent the degradation of communication quality.SOLUTION: An optical transmission system comprises: a transmitter (100); and a receiver (200). The transmitter (100) adds, to a signal, transmission wavelength information for specifying a transmission wavelength set in the transmitter (100), and transmits it to the receiver (200) side. The receiver (200) obtains the transmission wavelength information added to the signal transmitted from the transmitter (100), compares the transmission wavelength information with reception wavelength information for specifying a reception wavelength set in the receiver (200), and detects whether the transmission wavelength set in the transmitter (100) and the reception wavelength set in the receiver (200) discord or not.

Description

  The present invention relates to an optical transmission system that performs long-distance transmission.

  First, a problem situation that occurs in an optical transmission system related to the present invention will be described with reference to FIG. The optical transmission system shown in FIG. 3 includes a transmitter 100 ′ and a receiver 200 ′, and transmits a wavelength division multiplexed (WDM) optical signal from the transmitter 100 ′ to the receiver 200 ′.

  In the optical transmission system shown in FIG. 3, when the receiver 200 ′ side is equipped with a TDC (Tunable Dispersion Compensator), it is necessary to set a reception wavelength in the TDC. In FIG. 3, it is assumed that the reception wavelength of TDC is set to λ1 among the reception wavelengths of λ1 to λ3. Due to the characteristics of TDC, there is a passband (λ3 in FIG. 3) every fixed period in addition to λ1. However, characteristic quality cannot be guaranteed for passbands other than the reception wavelength λ1 set to TDC.

  In the case of FIG. 3 (a), since the transmission side setting wavelength λ1 and the reception side setting wavelength λ1 match, a desired communication quality can be obtained. The transmission side set wavelength is a transmission wavelength set on the transmitter 100 ′ side, and the reception side set wavelength is a reception wavelength set on the receiver 200 ′ side. In the case of FIG. 3A, the transmitter 100 ′ side sets λ1 from among the reception wavelengths λ1 to λ3, and the receiver 200 ′ side sets λ1 from the reception wavelengths λ1 to λ3. State.

  In the case of FIG. 3B, the transmission side setting wavelength λ2 and the reception side setting wavelength λ1 do not match due to a setting error on the reception side. Since there is no λ2 in the passband of the receiving side set wavelength, the main signal is disconnected, and an alarm indicating that the transmission and reception wavelengths do not match is output. In the case of FIG. 3B, the transmitter 100 ′ side sets λ2 from the received wavelengths λ1 to λ3, and the receiver 200 ′ side sets λ1 from the received wavelengths λ1 to λ3. State.

  In the case of FIG. 3C, the setting wavelength λ3 on the transmission side and the setting wavelength λ1 on the reception side do not match due to a setting mistake on the reception side. Since λ3 exists in the passband of the reception side set wavelength, the receiver 200 ′ side can receive a signal. However, the receiver 200 ′ cannot obtain a desired communication quality because of the poor passband characteristic of λ3 on the receiving side. In the case of FIG. 3 (c), the transmitter 100 ′ side sets λ3 from the reception wavelengths λ1 to λ3, and the receiver 200 ′ side sets λ1 from the reception wavelengths λ1 to λ3. State.

  As described above, in the optical transmission system related to the present invention, when the receiver 200 ′ side is mounted with TDC, even if the transmission side setting wavelength and the reception side setting wavelength do not match, the receiver 200 ′ side May receive signals and cannot detect mismatches in transmission and reception wavelengths. If the transmission-side set wavelength and the reception-side set wavelength do not match, the communication quality deteriorates and a situation in which desired communication characteristics cannot be satisfied occurs.

  For this reason, even in the case of FIG. 3C, it is considered necessary to detect a mismatch in transmission and reception wavelengths and prevent deterioration of communication quality.

  In addition, as technical documents filed prior to the present invention, for example, Patent Document 1; Japanese Patent Laid-Open No. 62-51321 discloses information on the optical input level monitored by the photoelectric conversion circuit of the receiving unit. A technique for transmitting to an opposing device as overhead information and controlling the light output level of the electrical conversion circuit of the transmission unit of the opposing device based on the information is disclosed.

  In Patent Document 1, by controlling the light output level of the electric conversion circuit, the load of the light emitting element is made appropriate according to the transmission path distance, and the load in the case of a short distance can be reduced. . Further, it is possible to prevent unnecessary excessive light input to the light receiving element in the case of a short distance.

  Patent Document 2; Japanese Patent Application Laid-Open No. 2010-41444 discloses a technique that can automate the transmission wavelength setting of the optical wavelength conversion unit, save labor in wavelength setting work, and reduce setting errors. Has been.

  In the above-mentioned Patent Document 2, wavelength information is superimposed on transmission data, and the wavelength information is extracted from received data. The wavelength is sequentially changed at the time of initial setting, and the wavelength of the output signal is combined with the optical wavelength. Wavelength information is exchanged with the opposite side when the wavelength of the connection port of the wave part matches, enabling automatic wavelength setting.

JP-A-62-51321 JP 2010-41444 A

  Patent Documents 1 and 2 disclose a technique for transmitting information between devices and performing various controls based on the information.

  However, Patent Documents 1 and 2 do not describe or suggest any point of detecting a mismatch between the transmission side set wavelength set on the transmitter side and the reception side set wavelength set on the receiver side. Patent Document 2 discloses a technique for automating transmission wavelength setting of an optical wavelength converter. However, the above-mentioned Patent Document 2 does not set the reception wavelength on the receiver side, and as in the present invention, even in the case of FIG. There is no description or suggestion about preventing deterioration.

  The present invention has been made in view of the above circumstances, and provides an optical transmission system, a receiver, a control method, and a program capable of detecting a mismatch in transmission and reception wavelengths and preventing deterioration in communication quality. Objective.

  In order to achieve this object, the present invention has the following features.

<Optical transmission system>
An optical transmission system according to the present invention includes:
An optical transmission system composed of a transmitter and a receiver,
The transmitter is
Transmission means for adding transmission wavelength information for specifying a transmission wavelength set in the transmitter to a signal and transmitting the signal to the receiver side;
The receiver is
Receiving means for acquiring the transmission wavelength information added to the signal transmitted from the transmitter;
The transmission wavelength information is compared with the reception wavelength information for specifying the reception wavelength set in the receiver, the transmission wavelength set in the transmitter, and the reception wavelength set in the receiver Detecting means for detecting whether or not
It is characterized by having.

<Receiver>
The receiver according to the present invention is:
Receiving means for receiving an OTN (Optical Transport Network) frame in which transmission wavelength information for specifying a transmission wavelength of a transmitter is mapped, and acquiring the transmission wavelength information from the received OTN frame;
The transmission wavelength information is compared with the reception wavelength information for specifying the reception wavelength set in the receiver, the transmission wavelength set in the transmitter, the reception wavelength set in the receiver, Detecting means for detecting whether or not
It is characterized by having.

<Control method>
The control method according to the present invention includes:
A control method performed by a receiver,
Receiving an OTN (Optical Transport Network) frame in which transmission wavelength information for specifying a transmission wavelength of a transmitter is mapped, and acquiring the transmission wavelength information from the received OTN frame;
The transmission wavelength information is compared with the reception wavelength information for specifying the reception wavelength set in the receiver, the transmission wavelength set in the transmitter, and the reception wavelength set in the receiver Detecting whether or not
It is characterized by having.

<Program>
The program according to the present invention is:
On the receiver computer,
A process of receiving an OTN (Optical Transport Network) frame in which transmission wavelength information for specifying a transmission wavelength of a transmitter is mapped, and acquiring the transmission wavelength information from the received OTN frame;
The transmission wavelength information is compared with the reception wavelength information for specifying the reception wavelength set in the receiver, the transmission wavelength set in the transmitter, and the reception wavelength set in the receiver , And a process of detecting whether or not are inconsistent.

  According to the present invention, it is possible to detect a mismatch between transmission and reception wavelengths and prevent deterioration of communication quality.

It is a figure for demonstrating the outline | summary of the optical transmission system of this embodiment. It is a figure which shows the system configuration example of the optical transmission system of this embodiment. It is a figure for demonstrating the problem condition which generate | occur | produces in the optical transmission system relevant to this invention.

<Outline of optical transmission system>
First, the outline of the optical transmission system of the present embodiment will be described with reference to FIG.

  The optical transmission system according to the present embodiment is an optical transmission system including a transmitter 100 and a receiver 200.

  The transmitter 100 according to the present embodiment includes a transmission unit 101 that adds transmission wavelength information for specifying a transmission wavelength set in the transmitter 100 to a signal and transmits the signal to the receiver 200 side.

  In addition, the receiver 200 of the present embodiment specifies a reception unit 201 that acquires transmission wavelength information added to a signal transmitted from the transmitter 100, and specifies the transmission wavelength information and the reception wavelength set in the receiver 200. And a detection unit 202 that detects whether or not the transmission wavelength set in the transmitter 100 and the reception wavelength set in the receiver 200 are inconsistent with each other. .

  The optical transmission system of the present embodiment has the above-described configuration, so that the receiver 200 compares the transmission wavelength set in the transmitter 100 with the reception wavelength set in the receiver 200, and determines that the transmission / reception wavelength does not match. Can be detected. As a result, deterioration of communication quality can be prevented. Hereinafter, the optical transmission system of this embodiment will be described in detail with reference to the accompanying drawings.

<System configuration example of optical transmission system>
First, a system configuration example of the optical transmission system according to the present embodiment will be described with reference to FIG.

  The optical transmission system according to this embodiment includes a transmitter 100 and a receiver 200.

  The transmitter 100 of this embodiment includes an O / E (1), an OTN (Optical Transport Network) Framer (2), an E / O (3), an OH (Over Head) insertion circuit (4), and a transmission And a wavelength setting circuit (5).

  The O / E (1) performs O / E (optical / electrical) conversion of the client optical signal to obtain the client electric signal. The OTN Framer (2) maps the Client electrical signal converted by the O / E (1) to an OTN (Optical Transport Network) frame. The OTN Framer (2) maps the OH information input from the OH insertion circuit (4) to the OTN frame. In the OH information, transmission wavelength information for specifying the transmission wavelength set on the transmitter 100 side is added and stored in the OH of the OTN frame. The E / O (3) performs E / O (electrical / optical) conversion on the OTN frame mapped by the OTN Framer (2), and transmits the WDM optical signal to the receiver 200 side. The transmission wavelength setting circuit (5) sets the transmission wavelength of the WDM signal transmitted by E / O (3), and outputs transmission wavelength information to identify the set transmission wavelength to the OH insertion circuit (4) To do. The OH insertion circuit (4) adds the transmission wavelength information input from the transmitter adjustment circuit (5) to the OH information and outputs it to the OTN Framer (2).

  The receiver 200 of this embodiment includes a TDC (Tunable Dispersion Compensator) (6), an O / E (7), an OTN Framer (8), an E / O (9), and a reception wavelength setting circuit (10). And an OH extraction circuit (11), a wavelength comparison circuit (12), and a Shut Down circuit (13).

  TDC (6) performs dispersion compensation of the WDM optical signal received from the transmitter 100 side, and O / E (7) performs O / E conversion of the WDM optical signal that has been dispersion-compensated by TDC (6). Get the frame. The OTN Framer (8) demaps the Client electrical signal from the OTN frame converted by the O / E (7). The E / O (9) performs E / O (electric / optical) conversion on the Client electrical signal demapped by the OTN Framer (8), and outputs a Client optical signal. The reception wavelength setting circuit (10) sets the reception wavelength to be received by the TDC (6) and outputs reception wavelength information for specifying the reception wavelength set in the TDC (6) to the wavelength comparison circuit (12). To do. The OH extraction circuit (11) extracts the OH information from the OH of the OTN frame demapped by the OTN Framer (8), and specifies the transmission wavelength on the transmitter 100 side from the extracted OH information Information is output to the wavelength comparison circuit (12). The wavelength comparison circuit (12) compares the transmission wavelength information input from the OH extraction circuit (11) with the reception wavelength information input from the reception wavelength setting circuit (10), and detects a mismatch in transmission and reception wavelengths. . The wavelength comparison circuit (12) issues a Shut Down instruction to the Shut Down circuit (13) when the transmission and reception wavelengths do not match. If the transmission / reception wavelengths are not inconsistent, a Shut Down release instruction is issued to the Shut Down circuit (13). The Shut Down circuit (13) shuts down the Client optical signal output from the E / O (9) according to the instruction of the wavelength comparison circuit (12).

<Processing operation example of optical transmission system>
Next, a processing operation example of the optical transmission system according to the present embodiment will be described with reference to FIG.

  First, a processing operation example on the transmitter 100 side will be described.

  The transmission wavelength setting circuit (5) sets the transmission wavelength of the WDM signal transmitted from the E / O (3) and outputs the transmission wavelength information for specifying the set transmission wavelength to the OH insertion circuit (4). To do. The OH insertion circuit (4) adds the transmission wavelength information input from the transmission wavelength setting circuit (5) to the OH information and outputs it to the OTN Framer (2). The OTN Framer (2) maps the OH information input from the OH insertion circuit (4) to the OTN frame, and stores the transmission wavelength information in the OH unused area of the OTN frame. The OTN frame in which the transmission wavelength information is stored in OH is E / O converted in E / O (3) and transmitted to the receiver 200 as a WDM optical signal.

  Next, an example of processing operation on the receiver 200 side will be described.

  The receiver 200 receives the WDM optical signal transmitted from the transmitter 100 by the TDC (6) and performs dispersion compensation. The O / E (7) performs O / E conversion on the WDM optical signal dispersion-compensated by the TDC (6) to obtain an OTN frame. The reception wavelength setting circuit (10) sets the reception wavelength to be received by the TDC (6) and outputs reception wavelength information for specifying the reception wavelength set in the TDC (6) to the wavelength comparison circuit (12). To do. The OTN Framer (8) demaps the Client electrical signal from the OTN frame converted by the O / E (7). The OH extraction circuit (11) extracts the OH information from the OH of the OTN frame demapped by the OTN Framer (8), and specifies the transmission wavelength on the transmitter 100 side from the extracted OH information Information is output to the wavelength comparison circuit (12).

  The wavelength comparison circuit (12) compares the transmission wavelength information input from the OH extraction circuit (11) with the reception wavelength information input from the reception wavelength setting circuit (10), and detects a mismatch in transmission and reception wavelengths. . When the wavelength comparison circuit (12) detects a mismatch between the transmission and reception wavelengths, it outputs an alarm indicating that the transmission and reception wavelengths do not match. Further, the wavelength comparison circuit (12) instructs the Shut Down circuit (13) to Shut Down, and Shuts down the Client optical signal output from the E / O (9). In addition, when the wavelength comparison circuit (12) detects a coincidence between the transmission and reception wavelengths, it instructs the Shut Down circuit (13) to release the Shut Down, and outputs the client optical signal from the E / O (8). .

<Operation and effect of optical transmission system of this embodiment>
Thus, in the optical transmission system of the present embodiment, the transmitter 100 side adds transmission wavelength information for specifying the transmission wavelength on the transmitter 100 side to the main signal and transmits it to the receiver 200. The receiver 200 side can specify the transmission wavelength on the transmitter 100 side based on the transmission wavelength information added to the main signal. When the receiver 200 detects a mismatch between the transmission wavelength on the transmitter 100 side and the reception wavelength on the receiver 200 side, the receiver 200 informs that the transmission / reception wavelength does not match and shifts to normal operation Can be avoided. Since the receiver 200 shifts to normal operation when the main signal is confirmed to be conductive, if the main signal is confirmed to be conductive, the receiver 200 shifts to normal operation. In this embodiment, when a mismatch in transmission / reception wavelengths is detected, a shift to normal operation can be avoided, so that deterioration in communication quality due to a mismatch in transmission / reception wavelengths can be suppressed.

  The receiver 200 can shut down the output of the client optical signal when detecting the mismatch of the transmission and reception wavelengths.

  The above-described embodiment is a preferred embodiment of the present invention, and the scope of the present invention is not limited to the above-described embodiment alone, and various modifications are made without departing from the gist of the present invention. Implementation is possible.

  For example, the above-described mapping and demapping methods to the OTN frame are not particularly limited, and various mapping and demapping methods can be applied.

  Further, the control operation in the transmitter 100 and the receiver 200 of the present embodiment described above can be executed using hardware, software, or a combination of both.

  In the case of executing processing using software, it is possible to install and execute a program in which a processing sequence is recorded in a memory in a computer incorporated in dedicated hardware. Alternatively, the program can be installed and executed on a general-purpose computer capable of executing various processes.

  For example, the program can be recorded in advance on a hard disk or ROM (Read Only Memory) as a recording medium. Alternatively, the program can be stored (recorded) temporarily or permanently in a removable recording medium. Such a removable recording medium can be provided as so-called package software. Removable recording media include floppy (registered trademark) disks, CD-ROM (Compact Disc Read Only Memory), MO (Magneto optical) disks, DVD (Digital Versatile Disc), Blu-ray discs, magnetic disks, semiconductor memories, etc. Can be mentioned.

  The program is installed in the computer from the removable recording medium as described above. In addition, it is wirelessly transferred from the download site to the computer. In addition, it is transferred to the computer via a network by wire.

  In addition, the optical transmission system in the present embodiment is not only executed in time series according to the processing operation described in the above embodiment, but also the processing capability of the apparatus that performs the processing, or in parallel as necessary. It can also be constructed to run individually.

  Moreover, although a part or all of said embodiment can be described also as the following additional remarks, it is not restricted to the following.

(Appendix 1)
An optical transmission system composed of a transmitter and a receiver,
The transmitter is
Transmission means for adding transmission wavelength information for specifying a transmission wavelength set in the transmitter to a signal and transmitting the signal to the receiver side;
The receiver is
Receiving means for acquiring the transmission wavelength information added to the signal transmitted from the transmitter;
The transmission wavelength information is compared with the reception wavelength information for specifying the reception wavelength set in the receiver, the transmission wavelength set in the transmitter, and the reception wavelength set in the receiver Detecting means for detecting whether or not
An optical transmission system comprising:

(Appendix 2)
The receiver is
When the detection unit detects that the transmission wavelength set in the transmitter and the reception wavelength set in the receiver do not match, it notifies that the transmission and reception wavelengths do not match. The optical transmission system according to appendix 1.

(Appendix 3)
The receiver is
When the detection means detects that the transmission wavelength set in the transmitter does not match the reception wavelength set in the receiver, the signal received from the transmitter is shut down. The optical transmission system according to appendix 1 or 2.

(Appendix 4)
The receiver is
Variable dispersion compensation means for performing dispersion compensation of a signal received by the receiver;
4. The optical transmission system according to any one of appendices 1 to 3, wherein the reception wavelength set in the receiver is the reception wavelength set in the variable dispersion compensation unit.

(Appendix 5)
The transmission means includes
The transmission wavelength information is mapped to an OTN (Optical Transport Network) frame and transmitted to the receiver side,
The receiving means includes
The optical transmission system according to any one of appendices 1 to 4, wherein the transmission wavelength information is acquired from the OTN frame.

(Appendix 6)
Receiving means for receiving an OTN (Optical Transport Network) frame in which transmission wavelength information for specifying a transmission wavelength of a transmitter is mapped, and acquiring the transmission wavelength information from the received OTN frame;
The transmission wavelength information is compared with the reception wavelength information for specifying the reception wavelength set in the receiver, the transmission wavelength set in the transmitter, the reception wavelength set in the receiver, Detecting means for detecting whether or not
A receiver comprising:

(Appendix 7)
The receiver is
Variable dispersion compensation means for performing dispersion compensation of a signal received by the receiver;
7. The receiver according to appendix 6, wherein the reception wavelength set in the receiver is a reception wavelength set in the variable dispersion compensation means.

(Appendix 8)
A control method performed by a receiver,
Receiving an OTN (Optical Transport Network) frame in which transmission wavelength information for specifying a transmission wavelength of a transmitter is mapped, and acquiring the transmission wavelength information from the received OTN frame;
The transmission wavelength information is compared with the reception wavelength information for specifying the reception wavelength set in the receiver, the transmission wavelength set in the transmitter, and the reception wavelength set in the receiver Detecting whether or not
A control method characterized by comprising:

(Appendix 9)
The receiver is
Variable dispersion compensation means for performing dispersion compensation of a signal received by the receiver;
The control method according to appendix 8, wherein the reception wavelength set in the receiver is the reception wavelength set in the variable dispersion compensation means.

(Appendix 10)
On the receiver computer,
A process of receiving an OTN (Optical Transport Network) frame in which transmission wavelength information for specifying a transmission wavelength of a transmitter is mapped, and acquiring the transmission wavelength information from the received OTN frame;
The transmission wavelength information is compared with the reception wavelength information for specifying the reception wavelength set in the receiver, the transmission wavelength set in the transmitter, and the reception wavelength set in the receiver , And a process for detecting whether or not are inconsistent.

(Appendix 11)
The receiver is
Variable dispersion compensation means for performing dispersion compensation of a signal received by the receiver;
The program according to claim 10, wherein the reception wavelength set in the receiver is the reception wavelength set in the variable dispersion compensation means.

100 Transmitter 101 Transmitter 1 O / E
2 OTN Framer
3 E / O
4 OH Insertion Circuit 5 Transmission Wavelength Setting Circuit 200 Receiver 201 Reception Unit 202 Detection Unit 6 TDC (Variable Dispersion Compensation Means)
7 O / E
8 OTN Framer
9 E / O
10 Reception wavelength setting circuit 11 OH extraction circuit 12 Wavelength comparison circuit 13 Shut Down circuit

Claims (8)

An optical transmission system composed of a transmitter and a receiver,
The transmitter is
Transmission means for adding transmission wavelength information for specifying a transmission wavelength set in the transmitter to a signal and transmitting the signal to the receiver side;
The receiver is
Receiving means for acquiring the transmission wavelength information added to the signal transmitted from the transmitter;
The transmission wavelength information is compared with the reception wavelength information for specifying the reception wavelength set in the receiver, the transmission wavelength set in the transmitter, and the reception wavelength set in the receiver Detecting means for detecting whether or not
An optical transmission system comprising: The receiver is
When the detection unit detects that the transmission wavelength set in the transmitter and the reception wavelength set in the receiver do not match, it notifies that the transmission and reception wavelengths do not match. The optical transmission system according to claim 1. The receiver is
When the detection means detects that the transmission wavelength set in the transmitter does not match the reception wavelength set in the receiver, the signal received from the transmitter is shut down. The optical transmission system according to claim 1 or 2. The receiver is
Variable dispersion compensation means for performing dispersion compensation of a signal received by the receiver;
4. The optical transmission system according to claim 1, wherein the reception wavelength set in the receiver is a reception wavelength set in the variable dispersion compensation unit. 5. The transmission means includes
The transmission wavelength information is mapped to an OTN (Optical Transport Network) frame and transmitted to the receiver side,
The receiving means includes
The optical transmission system according to claim 1, wherein the transmission wavelength information is acquired from the OTN frame. Receiving means for receiving an OTN (Optical Transport Network) frame in which transmission wavelength information for specifying a transmission wavelength of a transmitter is mapped, and acquiring the transmission wavelength information from the received OTN frame;
The transmission wavelength information is compared with the reception wavelength information for specifying the reception wavelength set in the receiver, the transmission wavelength set in the transmitter, the reception wavelength set in the receiver, Detecting means for detecting whether or not
A receiver comprising: A control method performed by a receiver,
Receiving an OTN (Optical Transport Network) frame in which transmission wavelength information for specifying a transmission wavelength of a transmitter is mapped, and acquiring the transmission wavelength information from the received OTN frame;
The transmission wavelength information is compared with the reception wavelength information for specifying the reception wavelength set in the receiver, the transmission wavelength set in the transmitter, and the reception wavelength set in the receiver Detecting whether or not
A control method characterized by comprising: On the receiver computer,
A process of receiving an OTN (Optical Transport Network) frame in which transmission wavelength information for specifying a transmission wavelength of a transmitter is mapped, and acquiring the transmission wavelength information from the received OTN frame;
The transmission wavelength information is compared with the reception wavelength information for specifying the reception wavelength set in the receiver, the transmission wavelength set in the transmitter, and the reception wavelength set in the receiver , And a process for detecting whether or not are inconsistent.

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