US 2026/0254531 A1Published application

Measurement method, determination method, and measurement system

AssigneesNTT, Inc., Anritsu Corporation

InventorsHiroshi SHIBATA, Kohei WATANABE, Hiroshi YAMAMOTO, Ken ITO, Motohiro BANNO, Shinji MORIMOTO, Yosho KANDA

Life of this patent

Estimating the term…

Loading patent…

Abstract

In an experimental environment including a test system that adds an ASE noise to signal light between a transmitting transponder and a receiving transponder connected in a back-to-back manner, OSNR of the signal light and BER of the signal light received by the receiving transponder are measured while changing a ratio of the signal light to the ASE noise, SNRASE_test of the signal light to which the ASE noise is added is obtained, and total SNRTOT including the test system and the transponders is obtained. SNRTRX indicating an amount of the noise in the transponders is obtained. In a commercial environment in which the test system is provided at upstream of the receiving transponder between the transmitting transponder and the receiving transponder connected via an optical transmission network, the same measurement as in the experimental environment is performed, and GSNR of the optical transmission network is obtained.

Claims6

Dependent claims

A measurement method of a GSNR of an optical transmission network, the measurement method comprising:

measuring, in a first configuration in which a test unit that adds an ASE noise to first signal light output from a transmitter is provided between the transmitter and a receiver directly connected without going through the optical transmission network, a first OSNR of the first signal light and a first BER of the first signal light received by the receiver while changing a ratio of the first signal light to the ASE noise;
obtaining a first SNR of the first signal light to which the ASE noise is added by the test unit from the first OSNR;
obtaining a second SNR of the entire first configuration from the first BER;
obtaining an amount of noises in the transmitter and the receiver from a relationship between a reciprocal of the first SNR and a reciprocal of the second SNR when the ratio of the first signal light to the ASE noise is changed;
measuring, in a second configuration in which a test unit that adds an ASE noise to second signal light received by the receiver is provided at upstream of the receiver between a transmitter and the receiver connected via the optical transmission network, a second OSNR of the second signal light and a second BER of the second signal light received by the receiver while changing a ratio of the second signal light to the ASE noise;
obtaining a third SNR of the second signal light to which the ASE noise is added by the test unit from the second OSNR;
obtaining a fourth SNR of the entire second configuration from the second BER;
obtaining an amount of noises in a configuration including the optical transmission network, the transmitter, and the receiver from a relationship between a reciprocal of the third SNR and a reciprocal of the fourth SNR when the ratio of the second signal light to the ASE noise is changed;
and
obtaining the GSNR of the optical transmission network by subtracting the amount of the noise in the transmitter and the receiver from the amount of the noise in the configuration.

7 more elements

A measurement system that measures a GSNR of an optical transmission network, the measurement system comprising:

a first configuration in which a test unit that adds an ASE noise to first signal light output from a transmitter is provided between the transmitter and a receiver directly connected without going through the optical transmission network;
and
a second configuration in which a test unit that adds an ASE noise to second signal light received by the receiver is provided at upstream of the receiver between a transmitter and the receiver connected via the optical transmission network,
wherein in the first configuration,
a first OSNR of the first signal light and a first BER of the first signal light received by the receiver are measured while changing a ratio of the first signal light to the ASE noise,
a first SNR of the first signal light to which the ASE noise is added by the test unit is obtained from the first OSNR,
a second SNR of the entire first configuration is obtained from the first BER, and
an amount of noises in the transmitter and the receiver is obtained from a relationship between a reciprocal of the first SNR and a reciprocal of the second SNR when the ratio of the first signal light to the ASE noise is changed, and
in the second configuration,
a second OSNR of the second signal light and a second BER of the second signal light received by the receiver are measured while changing a ratio of the second signal light to the ASE noise,
a third SNR of the second signal light to which the ASE noise is added by the test unit is obtained from the second OSNR,
a fourth SNR of the entire second configuration is obtained from the second BER,
an amount of noises in a configuration including the optical transmission network, the transmitter, and the receiver is obtained from a relationship between a reciprocal of the third SNR and a reciprocal of the fourth SNR when the ratio of the second signal light to the ASE noise is changed, and
the GSNR of the optical transmission network is obtained by subtracting the amount of the noise in the transmitter and the receiver from the amount of the noise in the configuration.

11 more elements

Dependencies are inferred from the claim text.