Excitation light distribution device, excitation light distribution method, optical amplification system and node device

• US 9,083,142 B2
• Filed: 09/20/2011
• Issued: 07/14/2015
• Est. Priority Date: 10/22/2010
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Sakauchi, Masahiro
• Primary Examiner(s): Diacou, Ari M
• Application Number:
  US13/880,094
• Publication Number:
  US 20130222890A1
• Time in Patent Office: 1,393 Days
• Field of Search: 359/341.32
• US Class Current: 1/1
• CPC Class Codes: H01S 3/06754 Fibre amplifiers H01S3/06708 takes precedence
• CPC Class Codes: H01S 3/0912 Electronics or drivers for the pump source, i.e. details of drivers or circuitry specific for laser pumping laser diode drivers H01S5/042
• CPC Class Codes: H01S 3/094049 Guiding of the pump light
• CPC Class Codes: H01S 3/094061 Shared pump, i.e. pump light of a single pump source is used to pump plural gain media in parallel
• CPC Class Codes: H01S 3/13013 by controlling the optical pumping
• CPC Class Codes: H04B 10/291 in which processing or amplification is carried out without conversion of the main signal from optical form

Abstract

For the purpose of reducing the cost and power consumption of an optical amplification system provided with an optical amplifier, an excitation light distribution device of the present invention comprises an excitation light source output unit which outputs excitation light, an optical branching unit with variable branching ratio which branches and outputs the excitation light, and a control unit which, on the basis of information on an optical signal to be amplified by the excitation light outputted by the optical branching unit, controls at least either the branching ratio of the optical branching unit or the optical output power of the excitation light source output unit.

Claims

1. An excitation light distribution device comprising:

an excitation light source output unit that outputs excitation light;

an optical branching unit with variable branching ratio that branches and outputs said excitation light; and

a control unit that controls, on the basis of information on an optical signal to be amplified by the excitation light outputted by said optical branching unit, at least either the branching ratio of said optical branching unit or the optical output power of said excitation light source output unit.

2. The excitation light distribution device according to claim 1, wherein

said control unit controls at least either the branching ratio of said optical branching unit or the optical output power of said excitation light source output unit, on the basis of information on the number of optical signals to be amplified by the excitation light outputted by said optical branching unit and on optical paths on which said optical signals are transmitted.

3. The excitation light distribution device according to claim 1, wherein:

said optical branching unit comprises an excitation light monitoring unit that monitors the power of said excitation light outputted from said optical branching unit and that outputs an excitation light monitoring signal corresponding to the intensity of said excitation light; and

,

on the basis of said excitation light monitoring signal, said control unit controls the power of said excitation light outputted by said excitation light source output unit and the branching ratio of said optical branching unit.

4. An optical amplification system comprising:

the excitation light distribution device according to claim 1; and

an amplification unit that amplifies and outputs said optical signal by inputting an optical signal and excitation light outputted from said excitation light distribution device.

5. The optical amplification system according to claim 4, wherein said amplification unit is disposed on each optical path transmitting said optical signal.

6. The optical amplification system according to claim 4, further comprising:

an optical attenuation unit that attenuates the intensity of said excitation light inputted to said amplification unit; and

a gain block control unit that controls the attenuation amount of said optical attenuation unit.

7. The optical amplification system according to claim 6, further comprising:

an optical signal monitoring unit that monitors the intensity of said optical signal in output of said amplification unit and that outputs an optical monitoring signal corresponding to the intensity of said optical signal, wherein

said gain block control unit controls the attenuation amount of said optical attenuation unit on the basis of said optical monitoring signal.

8. A node device comprising:

the optical amplification system according to claim 4 which amplifies an inputted optical signal; and

a transponder accommodation unit that separates said optical signal amplified by said optical amplification system at each wavelength and that outputs the separated signals onto respective predetermined optical paths.

9. A node device comprising:

a transponder accommodation unit that combines optical signals outputted from an optical transmission unit into a wavelength-multiplexed signal and for outputting said optical signals to a predetermined optical path; and

the optical amplification system according to claim 4 which amplifies said optical signal outputted to said predetermined optical path.

10. An excitation light distribution method which comprises:

branching and outputting excitation light; and

,

on the basis of information on an optical signal to be amplified by said branched and outputted excitation light, controlling at least either the branching ratio of said excitation light or the optical output power of said excitation light.