Optical node device

Patent metadata

Field	Value
Publication number	US-10965375-B2
Application number	US-201916967691-A
Country	US
Kind code	B2
Filing date	Feb 8, 2019
Priority date	Feb 8, 2018
Publication date	Mar 30, 2021
Grant date	Mar 30, 2021

Abstract

An optical node device includes: a multicore optical amplification unit that amplifies collectively light transmitted along a multicore fiber; a separation unit that inputs the amplified light in each core to each of a plurality of input-side single-core fibers; an optical cross-connect switch that attenuates the light input from each of the plurality of input-side single-core fibers through an optical attenuator, separates the light in accordance with a wavelength, and outputs the separated light to an output-side single-core fiber of a plurality of output-side single-core fibers related to a respective output destination; a plurality of single-core optical amplification units that amplify the light transmitted along the corresponding output-side single-core fibers; and an output unit that outputs the light transmitted along each of the plurality of output-side single-core fibers to a multicore fiber. A control unit controls the optical attenuator and the single-core optical amplification unit based on input signal optical power and output optical signal power.

First claim

The invention claimed is:

1. An optical node device comprising:
a multicore optical amplification unit that includes a multicore fiber and amplifies collectively light transmitted along a plurality of cores of the multicore fiber;
a separation unit that inputs, to each of a plurality of input-side single-core fibers, the light transmitted along each of the plurality of cores of the multicore fiber;
an optical cross-connect switch that attenuates individually the light input from each of the plurality of input-side single-core fibers through an optical attenuator, separates the light in accordance with a wavelength, and outputs the separated light to an output-side single-core fiber of a plurality of output-side single-core fibers related to a respective output destination of the separated light;
a plurality of single-core optical amplification units that individually correspond to the plurality of output-side single-core fibers and amplify the light transmitted along the corresponding output-side single-core fibers;
an output unit that outputs the light transmitted along each of the plurality of output-side single-core fibers to each of the plurality of cores in a transmission multicore fiber; and
a control unit that controls the optical attenuator and the single-core optical amplification units based on input signal optical power corresponding to optical power before amplification of the multicore optical amplification unit and output optical signal power corresponding to optical power after amplification of the single-core optical amplification units.

2. The optical node device according to claim 1 , wherein the control unit controls the optical attenuator using an attenuation amount that is calculated based on the input signal optical power and a wavelength number of the light.

3. The optical node device according to claim 2 , wherein the control unit controls the optical attenuator using a result of performing correction of a gain tilt on the calculated attenuation amount based on the input signal optical power.

4. The optical node device according to claim 1 , wherein the control unit corrects, based on the input signal optical power, a target gain determined based on a wavelength number of the light, and controls the single-core optical amplification unit based on the corrected target gain, and a gain obtained based on the input signal optical power and the output optical signal power.

5. The optical node device according to claim 1 , wherein the control unit corrects the output optical signal power based on the input signal optical power, and controls the single-core optical amplification unit based on a gain that is calculated based on the input signal optical power and the corrected output optical signal power, and a target gain determined based on a wavelength number of the light.

6. The optical node device according to claim 1 , the optical cross-connect switch comprising:
a plurality of the optical attenuators that individually correspond to the plurality of input-side single-core fibers and attenuate the light input from the corresponding input-side single-core fibers;
a plurality of input-side wavelength selection switches that individually correspond to the plurality of optical attenuators, separate the light attenuated by the corresponding optical attenuators for each wavelength, and output the separated light in accordance with output destinations of the light; and
a plurality of output-side wavelength selection switches that individually correspond to the output destinations, multiplex the light output from the plurality of input-side wavelength selection switches in accordance with the corresponding output destinations, and output the light to the output-side single-core fibers related to the output destinations,
wherein the control unit regulates the attenuation amount so that optical powers of wavelengths in the input-side wavelength selection switch and the output-side wavelength selection switch become the same.

7. The optical node device according to claim 1 , wherein
the light has a wavelength of 1565 nm or more and 1625 nm or less, and
the multicore fiber in the multicore optical amplification unit is a cladding-pumped erbium-doped fiber with an inner clad radius of more than 80 microns and 18 or less cores.

Assignees

• Nippon Telegraph & Telephone

Inventors

• Ono Hirotaka
• Senoo Kazunori
• Suzuki Kenya
• Yamaguchi Keita
• Fukutoku Mitsunori
• Kawai Shingo
• Miyamoto Yutaka

Classifications

• H04J14/052

  using multicore fibre (mode multiplex systems H04J14/04) · CPC title

• H04B10/294 Primary

  in a multiwavelength system, e.g. gain equalisation · CPC title

• H04B10/293 Primary

  Signal power control · CPC title

• H04B10/2581

  Multimode transmission · CPC title

• G02B6/02042

  Multicore optical fibres · CPC title