US 11,990,727 B2
Monitoring apparatus for optical amplifier, optical amplifying system, and method of monitoring amplified optical signal
Emmanuel Le Taillandier De Gabory, Tokyo (JP); and Keiichi Matsumoto, Tokyo (JP)
Assigned to NEC CORPORATION, Tokyo (JP)
Appl. No. 16/978,460
Filed by NEC Corporation, Tokyo (JP)
PCT Filed Mar. 7, 2018, PCT No. PCT/JP2018/008713
§ 371(c)(1), (2) Date Sep. 4, 2020,
PCT Pub. No. WO2019/171484, PCT Pub. Date Sep. 12, 2019.
Prior Publication US 2021/0044077 A1, Feb. 11, 2021
Int. Cl. H01S 3/13 (2006.01); H01S 3/067 (2006.01); H01S 3/094 (2006.01); H01S 3/10 (2006.01); H01S 3/23 (2006.01); H04B 10/25 (2013.01); H04B 10/294 (2013.01); H04B 10/572 (2013.01); H04B 10/66 (2013.01); H04J 14/02 (2006.01)
CPC H01S 3/1301 (2013.01) [H01S 3/06737 (2013.01); H01S 3/06754 (2013.01); H01S 3/094007 (2013.01); H01S 3/094069 (2013.01); H01S 3/10015 (2013.01); H01S 3/1003 (2013.01); H01S 3/1305 (2013.01); H01S 3/2391 (2013.01); H04B 10/25 (2013.01); H04B 10/2942 (2013.01); H04B 10/572 (2013.01); H04B 10/66 (2013.01); H04J 14/02 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A monitoring apparatus for optical amplifier, comprising:
an optical filter configured to receive a monitor light beam of the optical amplifier and transmit a filtered monitor light beam within a set wavelength band;
a photoelectric converter configured to convert the filtered monitor light beam into a monitoring signal;
a circuit configured to generate spectrum information based on the monitoring signal, the spectrum information including information on a spectrum profile of output of the optical amplifier; and
an optical combiner configured to receive a plurality of output monitor light beams from the optical amplifier and transmit to the optical filter a selected one of the output monitor light beams as the monitor light beam, wherein
the optical filter includes a plurality of optical bandpass filters that each have a different fixed center wavelength and a fixed passband that each transmit the filtered monitor light beam with respect to the fixed passband,
the photoelectric converter includes a plurality of photodetectors that each convert the filtered monitor light beam with respect to the fixed passband of a corresponding optical bandpass filter into the monitoring signal with respect to the fixed passband of the corresponding optical bandpass filter, and
the circuit generates the spectrum information based on the monitoring signal with respect to the fixed passband of each optical bandpass filter.