US 11,870,497 B2
Optical receiving apparatus, optical transmission system, optical transmission method and computer program
Ryo Igarashi, Musashino (JP); Takuya Kanai, Musashino (JP); Masamichi Fujiwara, Musashino (JP); and Junichi Kani, Musashino (JP)
Assigned to NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo (JP)
Appl. No. 17/623,852
Filed by NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo (JP)
PCT Filed Jul. 1, 2019, PCT No. PCT/JP2019/026036
§ 371(c)(1), (2) Date Dec. 29, 2021,
PCT Pub. No. WO2021/001871, PCT Pub. Date Jan. 7, 2021.
Prior Publication US 2022/0368427 A1, Nov. 17, 2022
Int. Cl. H04B 10/61 (2013.01); H04J 14/02 (2006.01)
CPC H04B 10/61 (2013.01) [H04J 14/02 (2013.01)] 11 Claims
OG exemplary drawing
 
1. An optical reception device comprising:
a local light transmission unit configured to generate a plurality of local lights having different wavelengths, select, from among the plurality of generated local lights having different wavelengths, a local light having a wavelength that is closest to the wavelength of a received optical signal, and transmit the selected local light to a coherent receiver;
an optical splitter configured to receive the received optical signal and transmit the received optical signal to the coherent receiver via a first path; and
a wavelength detection unit configured to receive the received optical signal from the optical splitter via a second path, split the received optical signal into different paths according to wavelengths by using a wavelength multiplexer/demultiplexer, and output, to the local light transmission unit, a control signal for causing the local light transmission unit to output a local light having a frequency that corresponds to a path in which the optical signal is included.