US 11,757,554 B2
Optical branch insertion device and optical transmission system using optical branch insertion device
Masahiro Nakagawa, Musashino (JP); Kana Masumoto, Musashino (JP); and Hidetoshi Onda, Musashino (JP)
Assigned to Nippon Telegraph and Telephone Corporation, Tokyo (JP)
Appl. No. 17/437,510
Filed by Nippon Telegraph and Telephone Corporation, Tokyo (JP)
PCT Filed Mar. 12, 2020, PCT No. PCT/JP2020/010928
§ 371(c)(1), (2) Date Sep. 9, 2021,
PCT Pub. No. WO2020/195912, PCT Pub. Date Oct. 1, 2020.
Claims priority of application No. 2019-057567 (JP), filed on Mar. 26, 2019.
Prior Publication US 2022/0182169 A1, Jun. 9, 2022
Int. Cl. H04J 14/02 (2006.01)
CPC H04J 14/0212 (2013.01) 10 Claims
OG exemplary drawing
 
1. An optical add/drop multiplexer configured to drop or add an optical signal between the optical add/drop multiplexer and a transponder connected with a communication terminal, the optical signal being transmitted by wavelength division multiplexing to a light transmission path included in multiple different light transmission paths of a communication network, the optical add/drop multiplexer comprising:
an arrayed waveguide grating (AWG), included in a plurality of AWGs, connected between the light transmission path and the transponder included in a plurality of transponders, and configured to output, from a port to the transponder, an optical signal transmitted through the light transmission path and transmit, through a port to the light transmission path, the optical signal transmitted from the transponder;
an optical switch (SW) configured to transmit or cut off, an optical signal between the light transmission path and the AWG; and
an optical coupler configured to connect a plurality of ports of the AWG to the transponder through coupling or bifurcation, wherein the optical coupler is an N×N optical coupler that includes ports connectable with the plurality of ports of the AWG and includes ports connectable with the plurality of the transponders,
wherein a channel interval of ports of the AWG is a plurality of times larger than a channel interval of ports of the transponder, and transponder signals as optical signals of a plurality of different wavelengths to and from one or the plurality of transponders can pass through ports of the AWG, and
wherein when the plurality of AWGs and the plurality of transponders are provided and the communication network includes the multiple different light transmission paths, the optical SW is configured to transmit, to the multiple different light transmission paths, optical signals including transponder signals having an identical wavelength, transmitted from different transponders included in the plurality of transponders, and having passed through different AWGs included in the plurality of AWGs.