Monitor device and monitor method for monitoring transmission line

1. A monitor device for monitoring a transmission line, the monitor device comprising:

a memory; and

a processor coupled to the memory and the processor configured to:

compensate for a portion of chromatic dispersion on a plurality of electric signals indicating an electric field component of an optical signal received by a digital coherent reception from the transmission line;

compensate for deterioration due to a nonlinear optical effect on the plurality of electric signals on which the portion of chromatic dispersion is compensated;

compensate for a remaining chromatic dispersion except for a first compensation amount of the portion of chromatic dispersion among a total chromatic dispersion amount of the transmission line on the plurality of electric signals on which the deterioration due to the nonlinear optical effect is compensated;

evaluate quality of the plurality of electric signals on which the remaining chromatic dispersion are compensated;

acquire the first compensation amount of the portion of chromatic dispersion and a second compensation amount of the deterioration due to the nonlinear optical effect, when the evaluated quality satisfies a predetermined condition; and

convert the first compensation amount and the second compensation amount into a position on the transmission line and a power of the optical signal at the position, respectively, based on a look-up table in which a correspondence relationship between input values and output values is registered.

2. The monitor device according to claim 1 , wherein the processor is further configured to:

change the first compensation amount by a predetermined amount, and

adjust the second compensation amount for the changed first compensation amount so that the evaluated quality satisfies the predetermined condition.

3. The monitor device according to claim 1 , wherein the plurality of electric signals are held in the memory, and

wherein the processor is further configured to: read an electric signal held in the memory and compensate for the portion of chromatic dispersion on the electric signal.

4. A monitor method for monitoring a transmission line, the monitor method comprising:

compensating for a portion of chromatic dispersion on a plurality of electric signals indicating an electric field component of an optical signal received by a digital coherent reception from the transmission line;

compensating for deterioration due to a nonlinear optical effect on the plurality of electric signals on which the portion of chromatic dispersion is compensated;

compensating for a remaining chromatic dispersion except for a first compensation amount of the portion of chromatic dispersion among a total chromatic dispersion amount of the transmission line on the plurality of electric signals on which the deterioration due to the nonlinear optical effect is compensated;

evaluating quality of the plurality of electric signals on which the remaining chromatic dispersion are compensated;

acquiring the first compensation amount of the portion of chromatic dispersion and a second compensation amount of the deterioration due to the nonlinear optical effect, when the evaluated quality satisfies a predetermined condition, by a processor; and

converting the first compensation amount and the second compensation amount into a position on the transmission line and a power of the optical signal at the position, respectively, based on a look-up table in which a correspondence relationship between input values and output values is registered.

5. The monitor method according to claim 4 , wherein the processor is further configured to:

change the first compensation amount by a predetermined amount, and

adjust the second compensation amount for the changed first compensation amount so that the evaluated quality satisfies the predetermined condition.

6. The monitor method according to claim 4 , wherein the plurality of electric signals are held in a memory, and

wherein the processor is further configured to read an electric signal held in the memory and compensate for the portion of chromatic dispersion on the electric signal.

7. A monitor device for monitoring a transmission line, the monitor device comprising:

a memory; and

a processor coupled to the memory and wherein the processor is further configured to:

compensate for a portion of chromatic dispersion on a plurality of electric signals indicating an electric field component of an optical signal received by a digital coherent reception from the transmission line;

compensate for deterioration due to a nonlinear optical effect on the plurality of electric signals on which the portion of chromatic dispersion is compensated;

compensate for a remaining chromatic dispersion except for a first compensation amount of the portion of chromatic dispersion among a total chromatic dispersion amount of the transmission line on the plurality of electric signals on which the deterioration due to the nonlinear optical effect is compensated;

evaluate quality of the plurality of electric signals on which the remaining chromatic dispersion are compensated;

acquire the first compensation amount of the portion of chromatic dispersion and a second compensation amount of the deterioration due to the nonlinear optical effect, when the evaluated quality satisfies a predetermined condition;

input test data to a deep neural network by expressed an equation

y

=

f

⁡

(

∑

k

=

1

n

⁢

w

k

⁢

x

k

+

w

0

)

,

where x is input data, y is output data, and f is one of a sigmoid function, a ReLU function, or a Maxout function;

calculate an error between a data outputted from the deep neural network and an expected data;

adjust weighting coefficients and a constant of the deep neural network by an error propagation method such that the error becomes smaller than a predetermined value; and

convert the first compensation amount and the second compensation amount into a position on the transmission line and a power of the optical signal, respectively, based on the adjusted weighting coefficients and the adjusted constant of the deep neural network.