US 12,119,869 B2
Optical amplification estimation method, optical amplification estimation apparatus and computer program
Ryo Igarashi, Musashino (JP); Masamichi Fujiwara, Musashino (JP); and Takuya Kanai, Musashino (JP)
Assigned to NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo (JP)
Appl. No. 17/927,056
Filed by NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo (JP)
PCT Filed May 28, 2020, PCT No. PCT/JP2020/021142
§ 371(c)(1), (2) Date Nov. 22, 2022,
PCT Pub. No. WO2021/240730, PCT Pub. Date Dec. 2, 2021.
Prior Publication US 2023/0224034 A1, Jul. 13, 2023
Int. Cl. H04B 10/079 (2013.01)
CPC H04B 10/07955 (2013.01) [H04B 10/0797 (2013.01)] 7 Claims
OG exemplary drawing
 
1. An optical amplification estimation method comprising:
making, by an excitation light output unit connected to a first end of a first optical transmission line, an excitation light incident on the first optical transmission line;
making, by a monitoring unit connected to the same side as the first end of the first optical transmission line, a monitoring light incident on the first optical transmission line, the monitoring light has a wavelength different from a wavelength of the excitation light;
measuring, by the monitoring unit, an intensity of light incident on the monitoring unit when the excitation light is incident, and intensity of light incident on the monitoring unit when the excitation light is not incident;
estimating, by an amplification estimation unit, a gain of an optical signal in the first optical transmission line based on the light intensity measured in the measuring,
reflecting, by an optical reflection unit installed on an opposite side of the first end of the first optical transmission line, the incident monitoring light; and
terminating, by a terminator installed on the opposite side of the first end of the first optical transmission line, the incident excitation light, wherein
the first optical transmission line shares a portion of the first optical transmission line with a second optical transmission line used for an optical network unit and an optical line terminal to transmit and receive an optical signal to and from each other.