US 11,929,787 B2
Optical transmission apparatus and optical transmission method
Akihiro Tanabe, Musashino (JP); Takashi Mitsui, Musashino (JP); Tomoaki Yoshida, Musashino (JP); and Toshiaki Shitaba, Musashino (JP)
Assigned to NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo (JP)
Appl. No. 17/911,027
Filed by NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo (JP)
PCT Filed Mar. 13, 2020, PCT No. PCT/JP2020/011149
§ 371(c)(1), (2) Date Sep. 12, 2022,
PCT Pub. No. WO2021/181665, PCT Pub. Date Sep. 16, 2021.
Prior Publication US 2023/0099159 A1, Mar. 30, 2023
Int. Cl. H04B 10/03 (2013.01); H04B 10/294 (2013.01); H04B 10/572 (2013.01); H04B 10/61 (2013.01); H04B 10/032 (2013.01); H04B 10/07 (2013.01); H04J 14/02 (2006.01); H04Q 11/00 (2006.01)
CPC H04B 10/614 (2013.01) [H04B 10/294 (2013.01); H04B 10/572 (2013.01); H04B 10/03 (2013.01); H04B 10/032 (2013.01); H04B 10/07 (2013.01); H04J 14/02 (2013.01); H04J 14/0287 (2013.01); H04Q 2011/0081 (2013.01); H04Q 2011/0083 (2013.01)] 2 Claims
OG exemplary drawing
 
1. An optical transmission apparatus for redundantly transmitting a multiplexed signal obtained by multiplexing N (N is an integer of 2 or greater) optical signals having different wavelengths, the optical transmission apparatus comprising:
a first demultiplexing unit to which a first multiplexed signal is input, the first demultiplexing unit configured to demultiplex the input first multiplexed signal into the N optical signals;
N first detection units to which the N optical signals demultiplexed by the first demultiplexing unit are respectively input, each of the N first detection units configured to detect presence or absence of deterioration of a corresponding input optical signal of the input optical signals based on a signal level of the corresponding input optical signal;
a second demultiplexing unit to which a second multiplexed signal is input, the second demultiplexing unit configured to demultiplex the input second multiplexed signal into the N optical signals;
N second detection units to which the N optical signals demultiplexed by the second demultiplexing unit are respectively input, each of the N second detection units configured to detect presence or absence of deterioration of a corresponding input optical signal of the input optical signals based on a signal level of the corresponding input optical signal; and
a selection unit configured to select, based on detection result of presence or absence of deterioration of each of the optical signals by the first detection units and the second detection units, N optical signals having different wavelengths from either the optical signals demultiplexed by the first demultiplexing unit or the optical signals demultiplexed by the second demultiplexing unit;
wherein for each selected optical signal, difference between signal level of the selected optical signal and signal level of another optical signal having a wavelength adjacent to the wavelength of the selected signal is less than a threshold; and
a multiplexing unit configured to multiplex the N optical signals having different wavelengths selected by the selection unit.