IP Library › Granted Patent US 12,222,248
Granted Patent B2
US 12,222,248 · App. 17/763,363 · Granted Feb 11, 2025

Detection system, detection method, and detection device

Inventor: Takashi Kojima (Tokyo, JP)
Assignee: NEC CORPORATION
G01K11/32G01D21/02G01L1/242
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Quick Facts
Patent No.
US 12,222,248
App. No.
17/763,363
Filed
Mar 24, 2022
Granted
Feb 11, 2025
Kind
B2
Art Unit
2874
USPC
385/12
Abstract

A detection system according to the present disclosure includes an optical fiber ( 10 ) configured to detect environment information, an acquisition unit ( 21 ) configured to acquire the environment information included in an optical signal received from the optical fiber ( 10 ), and a detection unit ( 22 ) configured to detect an event in the vicinity of the optical fiber ( 10 ) on the basis of a first environment pattern based on environment information acquired from an optical signal associated to a first period and a second environment pattern based on environment information acquired from an optical signal associated to a second period.

Claims (35)

1. A detection system comprising:

an optical fiber having a plurality of sections and configured to detect environment information;

a memory storing instructions; and

at least one processor configured to execute the instructions to:

acquire, for each section, first and second environment information included in first and second optical signals received from the optical fiber and associated with first and second periods, respectively;

derive, for each section, a displacement between a first environment pattern based on the first environment information and a second environment pattern based on the second environment information;

detect, when the displacement for more than one section satisfies a predetermined condition, an event in a vicinity of the optical fiber that is associated with the predetermined condition; and

specify the section for which the displacement satisfying the predetermined condition is largest as being near a position where the event is occurring.

2. The detection system according to claim 1 , wherein the processor is configured to execute the instructions to:

generate the first environment pattern by integrating the first environment information; and

generate the second environment pattern by integrating the second environment information.

3. The detection system according to claim 1 , wherein the at least one processor is configured to execute the instructions to

detect the event based on a difference in the displacements in different sections.

4. The detection system according to claim 1 , wherein the environment information indicates at least one of temperature of the optical fiber, vibration of the optical fiber, and pressure applied to the optical fiber.

5. The detection system according to claim 1 , wherein the at least one processor is configured to execute the instructions to notify that the event has been detected.

6. The detection system according to claim 1 , wherein the environment information is detected from backscattered light generated in the optical fiber by emitted light.

7. A detection method performed by a detection system and comprising:

acquiring, for each section of a plurality of sections of an optical fiber configured to detect environment information, first and second environment information included in first and second optical signals received from the optical fiber and associated with first and second periods, respectively;

deriving, for each section, a displacement between a first environment pattern based on the first environment information and a second environment pattern based on the second environment information;

detecting, when the displacement for more than one section satisfies a predetermined condition, an event in a vicinity of the optical fiber that is associated with the predetermined condition; and

specifying the section for which the displacement satisfying the predetermined condition is largest as being near a position where the event is occurring.

8. The detection method according to claim 7 , comprising:

generating the first environment pattern by integrating the first environment information and

generating the second environment pattern by integrating the environment information.

9. The detection method according to claim 7 , comprising

detecting the event based on a difference in the displacements in different sections.

10. The detection method according to claim 7 , wherein the environment information indicates at least one of temperature of the optical fiber, vibration of the optical fiber, and pressure applied to the optical fiber is acquired.

11. The detection method according to claim 7 , further comprising notifying that the event has been detected.

12. A detection device comprising:

a memory storing instructions; and

at least one processor configured to execute the instructions to:

acquire, for each section of a plurality of sections of an optical fiber configured to detect environment information, first and second environment information included in first and second optical signals received from the optical fiber and associated with first and second periods, respectively;

derive, for each section, a displacement between a first environment pattern based on the first environment information and a second environment pattern based on the second environment information;

detect, when the displacement for more than one section satisfies a predetermined condition, an event in a vicinity of the optical fiber that is associated with the predetermined condition; and

specify the section for which the displacement satisfying the predetermined condition is largest as being near a position where the event is occurring.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Mar 24, 2022
From: KOJIMA, TAKASHI
To: NEC CORPORATION
Reel/Frame 059389/0136 →
Continuity (1)
Related Publication 20220334006A1 · Oct 20, 2022
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