Cyclic wavelength band replacement device, multi-band transmission system, and cyclic wavelength band replacement method

Patent metadata

Field	Value
Publication number	US-2023074213-A1
Application number	US-202017794426-A
Country	US
Kind code	A1
Filing date	Feb 4, 2020
Priority date	Feb 4, 2020
Publication date	Mar 9, 2023
Grant date	—

Abstract

A cyclic wavelength band permutation device (31) includes as many wavelength band converters (32a to 32c) as the wavelength bands of optical signals (S1, C1, and L1), and the wavelength band converters are individually connected to the output terminals of corresponding optical amplifiers among a plurality of optical amplifiers (17a to 17c) connected to an optical fiber (16) in an inserted manner. When a wavelength-multiplexed signal beam obtained by multiplexing optical signals in different wavelength bands is multiband-transmitted through an optical fiber while being amplified by the plurality of optical amplifiers, each wavelength band converter performs a cyclic permutation process of transitioning or converting an optical signal allocated to the shorter wavelength band side in the bands of the optical fiber to the longer wavelength band side, and also transitioning or converting an optical signal allocated to the longest wavelength band to the shortest wavelength band.

First claim

1 . A cyclic wavelength band permutation device comprising wavelength band converters, wherein:
when a wavelength-multiplexed signal beam obtained by multiplexing optical signals in different wavelength bands is multiband-transmitted through an optical fiber while being amplified by a plurality of optical amplifiers, the cyclic wavelength band permutation device includes as many wavelength band converters as the wavelength bands of the optical signals, each wavelength band converter being configured to perform a cyclic permutation process of transitioning or converting an optical signal allocated to a shorter wavelength band side in bands of the optical fiber to a longer wavelength band side, and also transitioning or converting an optical signal allocated to a longest wavelength band to a shortest wavelength band, and each wavelength band converter is connected to output terminals of corresponding optical amplifiers among the plurality of optical amplifiers.

2 . The cyclic wavelength band permutation device according to claim 1 , wherein:
as many wavelength band converters as the wavelength bands of the optical signals are counted as a unit of the cyclic permutation process, and a plurality of groups of wavelength band converters, each group forming a unit of the cyclic permutation process, are connected in a cascade arrangement.

3 . The cyclic wavelength band permutation device according to claim 2 , wherein each of the wavelength band converters is configured to, when the cyclic permutation process is performed, perform a process of reversing spectral characteristics of the wavelength bands of the optical signals that have been converted into bands in a transition destination so that the spectral characteristics become opposite to the spectral characteristics before the conversion.

4 . A multiband transmission system comprising the cyclic wavelength band permutation device according to claim 1 , the cyclic wavelength band permutation device being connected in an inserted manner to an optical fiber between a wavelength band multiplexer and a wavelength band separator,
the wavelength band multiplexer being configured to perform multiband transmission of a wavelength-multiplexed signal beam obtained by multiplexing optical signals in different wavelength bands to the optical fiber, and the wavelength band separator being configured to separate the multiband-transmitted optical signals into signals in the respective wavelength bands.

5 . A cyclic wavelength band permutation method performed with a cyclic wavelength band permutation device including wavelength band converters, wherein when a wavelength-multiplexed signal beam obtained by multiplexing optical signals in different wavelength bands is multiband-transmitted through an optical fiber while being amplified by a plurality of optical amplifiers, the cyclic wavelength band permutation device includes as many wavelength band converters as the wavelength bands of the optical signals, and each wavelength band converter is connected to output terminals of corresponding optical amplifiers among the plurality of optical amplifiers, the method comprising:
causing each wavelength band converter to execute a step of performing a cyclic permutation process of transitioning or converting an optical signal allocated to a shorter wavelength band side in bands of the optical fiber to a longer wavelength band side, and also transitioning or converting an optical signal allocated to a longest wavelength band to a shortest wavelength band.

6 . The cyclic wavelength band permutation method according to claim 5 , further comprising:
counting as a unit of the cyclic permutation process as many wavelength band converters as the wavelength bands of the optical signals, and connecting, in a cascade arrangement, a plurality of groups of wavelength band converters, each group forming a unit of the cyclic permutation process.

7 . The cyclic wavelength band permutation method according to claim 6 , further comprising:
reversing spectral characteristics of the wavelength bands of the optical signals that have been converted into bands in a transition destination so that the spectral characteristics become opposite to the spectral characteristics before the conversion.

8 . The multiband transmission system according to claim 4 , wherein:
as many wavelength band converters as the wavelength bands of the optical signals are counted as a unit of the cyclic permutation process, and a plurality of groups of wavelength band converters, each group forming a unit of the cyclic permutation process, are connected in a cascade arrangement.

9 . The multiband transmission system according to claim 8 , wherein each of the wavelength band converters is configured to, when the cyclic permutation process is performed, perform a process of reversing spectral characteristics of the wavelength bands of the optical signals that have been converted into bands in a transition destination so that the spectral characteristics become opposite to the spectral characteristics before the conversion.

Assignees

• Nippon Telegraph & Telephone

Inventors

• Kawahara Hiroki
• Seki Takeshi
• Suda Sachio
• Saito Kohei
• Hirose Kenta

Classifications

• H04J14/02216

  by gain equalization · CPC title

• H04J14/0261 Primary

  at the optical multiplex section layer · CPC title

• H04B10/2537 Primary

  due to scattering processes, e.g. Raman or Brillouin scattering · CPC title

• H04B10/506

  Multiwavelength transmitters · CPC title

• H04B10/291

  in which processing or amplification is carried out without conversion of the main signal from optical form · CPC title