OPTICAL TRANSMISSION DEVICE AND OPTICAL TRANSMISSION DEVICE CONTROL METHOD

• US 20140233943A1
• Filed: 12/04/2013
• Published: 08/21/2014
• Est. Priority Date: 02/21/2013
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: MAEDA, Yoshiyuki, YAMAKAMI, Masahiro, YOSHIMI, Makoto
• Granted Patent: US 9,191,143 B2
• Time in Patent Office: Days
• US Class Current: 398/34
• CPC Class Codes: H04B 10/07955 Monitoring or measuring power
• CPC Class Codes: H04B 10/506 Multiwavelength transmitters
• CPC Class Codes: H04B 10/564 Power control
• CPC Class Codes: H04J 14/0221 Power control, e.g. to keep the total optical power constant

Abstract

Each optical transmission device includes a detecting unit, a notifying unit, and a control unit. The detecting unit detects a value of the optical power of each of multiple wavelengths. The notifying unit notifies an optical transmission device at the upstream side of a control frame that includes the value and that includes information that indicates the execution state of the optical power control. The control unit calculates the adjustment level on the basis of the optical power of each of the wavelengths detected by the detecting unit. Furthermore, when the information included in the control frame sent from an optical transmission device at the downstream side indicates that the optical power control is being stopped, the control unit calculates the adjustment level on the basis of the value included in the control frame and executes optical power control by setting the calculated adjustment level to the optical device.

Claims

1. An optical transmission device comprising:

a detecting unit that detects a value of optical power of each of multiple wavelengths in wavelength multiplexed light that is targeted for transmission;

a notifying unit that notifies an optical transmission device at an upstream side that has sent signal light of each of the wavelengths of a control frame that includes the value of the optical power of each of the wavelengths detected by the detecting unit and that includes information that indicates an execution state of optical power control that controls an adjustment level set in an optical device that adjusts the optical power of each of the wavelengths; and

a control unit that calculates the adjustment level on the basis of the value of the optical power of each of the wavelengths detected by the detecting unit, that calculates, when the information included in the control frame sent from an optical transmission device at a downstream side indicates that the optical power control is being stopped, the adjustment level of the optical power of each of the wavelengths included in the control frame, and that sets the calculated adjustment level to the optical device so that the control unit executes the optical power control.

2. The optical transmission device according to claim 1, wherein

the control frame further includes device-by-wavelength identification information that is identification information on an optical transmission device at the upstream side that has sent the signal light of each of the wavelengths by associating the device-by-wavelength identification information with the value of the optical power of each of the wavelengths,

when the information indicates that the optical power control is being stopped, the control unit determines whether the device-by-wavelength identification information included in the control frame corresponds to the identification information on the optical transmission device at the upstream side,

when the device-by-wavelength identification information corresponds to the identification information on the optical transmission device at the upstream side, the control unit acquires, from the control frame, the value of the optical power of each of the wavelengths associated with the device-by-wavelength identification information and calculates the adjustment level on the basis of the acquired value of the optical power of each of the wavelengths, and

when the device-by-wavelength identification information does not correspond to the identification information on the optical transmission device at the upstream side, the control unit calculates the adjustment level on the basis of the value of the optical power of each of the wavelengths detected by the detecting unit.

3. The optical transmission device according to claim 1, further comprising an updating unit that updates firmware, wherein, when the firmware is updated by the updating unit, the notifying unit notifies the optical transmission device at the upstream side of the control frame that includes the information indicating that the optical power control is being stopped.

4. The optical transmission device according to claim 3, wherein

when the firmware has been updated by the updating unit, the notifying unit notifies the optical transmission device at the upstream side of the control frame that includes the information indicating that the optical power control is being executed, and

after the control unit receives the control frame that includes the information indicating that the optical power control is being stopped from the optical transmission device at the downstream side, when the control unit then receives the control frame that includes the information indicating that the optical power control is being executed from the optical transmission device at the downstream side, the control unit calculates the adjustment level on the basis of the value of the optical power of each of the wavelengths detected by the detecting unit and sets the calculated adjustment level to the optical device, by predetermined level, so that the control unit gradually adjusts the optical power of each of the wavelengths.

5. An optical transmission device control method comprising:

notifying, by using a detecting unit that detects a value of optical power of each of multiple wavelengths in wavelength multiplexed light that is targeted for transmission, an optical transmission device at an upstream side that has sent signal light of each of the wavelengths of a control frame that includes the detected value of the optical power of each of the wavelengths and that includes information that indicates an execution state of optical power control that controls an adjustment level set in an optical device that adjusts the optical power of each of the wavelengths;

calculating the adjustment level on the basis of the detected value of the optical power of each of the wavelengths;

calculating the adjustment level on the basis of the value of the optical power of each of the wavelengths included in the control frame when the information included in the control frame sent from an optical transmission device at a downstream side indicates that the optical power control is being stopped; and

executing the optical power control by setting the calculated adjustment level to the optical device.