Title:
DISTRIBUTED TYPE OPTICAL FIBER DISTORTION MEASUREMENT DEVICE, AND DISTRIBUTED TYPE OPTICAL FIBER DISTORTION MEASUREMENT METHOD
Document Type and Number:
Japanese Patent JP2022109456
Kind Code:
A
Abstract:
To enhance spatial resolving power by adjustment of a passive component.SOLUTION: A branch unit branches natural BS light generating in an optical fiber into a first optical path and second optical path. An optical frequency shifter unit is provided in the first optical path, and imparts an optical frequency shift propagating through the first optical path. A variable delay unit is provided in the second optical path, and imparts a delay of delay time τ to light propagating through the second optical path, in which the delay time τ is variable. A multiplexing unit multiplexes the light propagating through the first optical path and the light propagating through second optical path to generate multiplexed light. A coherent detection unit performs heterodyne detection of the multiplexed light to output a differential frequency as a beat signal. A mixer performs homodyne detection of the beat signal and locally generated electric signal, and outputs the result as a homodyne signal. A signal processing device performs prescribed processing on a phase difference signal included in the homodyne signal, and calculates a change in frequency of the natural BS light on the basis of a change in intensity of the beat signal.SELECTED DRAWING: Figure 1
Inventors:
MURAI HITOSHI
Application Number:
JP2021004771A
Publication Date:
July 28, 2022
Filing Date:
January 15, 2021
Export Citation:
Assignee:
OKI ELECTRIC IND CO LTD
International Classes:
G01B11/16; G01D5/353
Attorney, Agent or Firm:
Hiroyuki Okada
Takashi Ogaki
Takashi Ogaki
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