Optical wavelength multiplexing device, optical transmission device, and abnormality determination method

Patent metadata

Field	Value
Publication number	US-9838113-B2
Application number	US-201615079006-A
Country	US
Kind code	B2
Filing date	Mar 23, 2016
Priority date	Apr 15, 2015
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

Abstract

An optical wavelength multiplexing device includes: a wavelength selective switch including a first input port for receiving an optical signal, a second input port for receiving a monitoring signal, output ports for outputting the optical signal or the monitoring signal, and an adjustment unit that adjusts a level of the optical signal or the monitoring signal at one of the output ports; a measurement unit that measures an output level of the monitoring signal at one of the output ports; and a control unit that specifies an unused output port of the output ports as a monitoring target port; sets a specific adjustment amount to the monitoring target port; outputs the monitoring signal to the monitoring target port; and determines whether the monitoring target port has an abnormality, based on the output level at the monitoring target port and an estimated output level at the monitoring target port.

First claim

What is claimed is:

1. An optical wavelength multiplexing device comprising:
a wavelength selective switch that includes a first input port through which an optical signal is input, a second input port through which a monitoring signal corresponding to a monitoring optical signal is input, a plurality of output ports through which the optical signal or the monitoring signal is output, and an adjuster that adjusts a level of the optical signal or the monitoring signal output to one of the plurality of output ports;
a monitor that measures an output level of the monitoring signal at one of the plurality of output ports; and
a controller that controls the wavelength selective switch and the monitor;
wherein the controller:
specifies an unused output port from among the plurality of output ports as a monitoring target port;
sets an adjustment amount of the monitoring target port at a specific adjustment amount;
outputs the monitoring signal to the monitoring target port; and
determines whether the monitoring target port has an abnormality, based on the output level of the monitoring signal at the monitoring target port, which is measured by the monitor, and an estimated output level of the monitoring signal at the monitoring target port when the specific adjustment amount is set,

wherein the monitoring target port is specified by the controller at specific intervals.

2. The optical wavelength multiplexing device according to claim 1 , wherein the controller calculates the estimated output level at the monitoring target port, based on an input level of the monitoring signal at the second input port and the specific adjustment amount.

3. The optical wavelength multiplexing device according to claim 1 , wherein whether the monitoring target port has an abnormality is determined, based on a difference between the output level of the monitoring signal at the monitoring target port, which is measured in the monitor, and the estimated output level at the monitoring target port.

4. The optical wavelength multiplexing device according to claim 3 , wherein the controller monitors a time period in which the abnormality in the monitoring target port continues, and determines a failure in the wavelength selective switch when the time period in which the abnormality in the monitoring target port continues exceeds a certain time period.

5. An optical transmission device comprising:
a first wavelength selective switch that includes a first input port through which a first optical signal is input, a second input port through which a monitoring signal corresponding to a monitoring optical signal is input, a plurality of first output ports through which the first optical signal or the monitoring signal is output, a first adjuster that adjusts a level of the first optical signal or the monitoring signal output to one of the plurality of output ports;
a plurality of first optical dividers that are coupled to the respective first output port and divide the first optical signal or the monitoring signal;
a monitor that measures an output level of the monitoring signal at one of the plurality of first output ports, which is divided by the respective first optical dividers; and
a controller that controls the first wavelength selective switch and the monitor,
wherein the controller:
specifies an unused output port from among the plurality of first output ports as a monitoring target port, sets an adjustment amount of the monitoring target port at a specific adjustment amount;
outputs the monitoring signal to the monitoring target port; and
determines whether the monitoring target port has an abnormality, based on the output level of the monitoring signal at the monitoring target port, which is measured by the monitor, and an estimated output level of the monitoring signal at the monitoring target port when the specific adjustment amount is set,

wherein the monitoring target port is specified by the controller at specific intervals.

6. The optical transmission device according to claim 5 further comprising:
a second wavelength selective switch that includes a third input port through which a second optical signal is input, a second output port through which the second optical signal is output; and
a second adjuster that adjusts a level of the second optical signal output to the second output port.

7. The optical transmission device according to claim 5 further comprising:
a second optical divider that is coupled to the second output port and divides the second optical signal, wherein an output level of one of the divided second optical signals is measured by the monitor.

8. The optical transmission device according to claim 5 , wherein the controller calculates the estimated output level at the monitoring target port, based on an input level of the monitoring signal at the second input port and the specific adjustment amount.

9. The optical transmission device according to claim 5 , wherein whether the monitoring target port has an abnormality is determined, based on a difference between the output level of the monitoring signal at the monitoring target port, which is measured in the monitor, and the estimated output level at the monitoring target port.

10. The optical transmission device according to claim 9 , wherein the controller monitors a time period in which the abnormality in the monitoring target port continues, and determines a failure in the first wavelength selective switch when the time period in which the abnormality in the monitoring target port continues exceeds a certain time period.

11. An abnormality determination method comprising:
receiving an optical signal at a first input port;
receiving a monitoring signal corresponding to a monitoring optical signal at a second input port;
outputting the optical signal or the monitoring signal through a plurality of output ports;
adjusting a level of the optical signal or the monitoring signal output to one of the plurality of output ports;
measuring an output level of the monitoring signal at one of the plurality of output ports;
specifying an unused output port from among the plurality of output ports as a monitoring target port;
setting an adjustment amount of the specified monitoring target port at a specific adjustment amount;
outputting the monitoring signal to the monitoring target port; and
determining whether the monitoring target port has an abnormality, based on the measured output level of the monitoring signal at the monitoring target port and the estimated output level of the monitoring signal at the monitoring target port when the specific adjustment amount is set,
wherein the monitoring target port is specified by the controller at specific intervals.

12. The abnormality determination method according to claim 11 , wherein the estimated output level at the monitoring target port is calculated based on an input level of the monitoring signal at the second input port and the specific adjustment amount.

13. The abnormality determination method according to claim 11 , wherein whether the monitoring target port has an abnormality is determined, based on a difference between the output level of the monitoring signal at the monitoring target port and the estimated output level at the monitoring target port.

14. The abnormality determination method according to claim 13 , further comprising:
monitoring a time period in which the abnormality in the monitoring target port continues; and
determining a failure in the wavelength selective switch when the time period in which the abnormality in the monitoring target port continues exceeds a certain time period.

Assignees

• Fujitsu Ltd

Inventors

• Ejima Kota
• Yamakami Masahiro
• Yoshimura Satoshi
• Tochigi Takumi
• Yoshimi Makoto

Classifications

• H04J14/0212

  using optical switches or wavelength selective switches [WSS] · CPC title

• H04B10/0791 Primary

  Fault location on the transmission path · CPC title

• H04B10/0795

  Performance monitoring; Measurement of transmission parameters · CPC title

• H04J14/0283

  WDM ring architectures · CPC title