# US 12,000,729 B2 · Perpendicular distance prediction of vibrations by distributed fiber optic sensing

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 12,000,729 B2
- Document ID: US12000729B2
- Status: Granted
- Kind: B2
- Application number: 17/555,990
- Filed: 2021-12-20
- Published: 2022-06-23
- Granted: 2024-06-04
- Earliest claimed: 2020-12-22
- Assignees: NEC Corporation
- Applicants: NEC Laboratories America, Inc.
- Inventors: Shaobo Han; Ming-Fang Huang; Yuheng Chen; Milad Salemi
- Web page: https://patentgrep.com/patent/US12000729B2

## CPC

- G01H 9/004: {using fibre optic sensors (light guides per se G02B6/00, acousto-optical devices specially adapted for gating or modulating in optical wave guides G02F1/125)}
- G06N 7/01: Probabilistic graphical models, e.g. probabilistic networks
- G06V 10/28: Quantising the image, e.g. histogram thresholding for discrimination between background and foreground patterns
- G06V 10/449: {Biologically inspired filters, e.g. difference of Gaussians [DoG] or Gabor filters}
- G06T 2207/30181: Earth observation
- G01H: MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G06N: COMPUTING ARRANGEMENTS BASED ON SPECIFIC COMPUTATIONAL MODELS
- G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL

## Abstract

Distributed fiber optic sensing (DFOS) systems, methods and structures for determining the proximity of vibration sources located perpendicular to a sensor fiber that is part of the DFOS system that may potentially threaten/damage or otherwise compromise the sensor fiber itself. Systems, methods, and structures according to aspects of the present disclosure employ Artificial Intelligence (AI) methodology(ies) that use as input a fundamental physical understanding of wave propagation and attenuation in the ground along with Bayesian inference and Maximum Likelihood Estimation (MLE) techniques for estimating/determining the proximity of potentially damaging vibration sources to the optical sensor fiber.

## Claims

### Claim 1

A method of operating a distributed fiber optic sensing (DFOS)/distributed acoustic sensing (DAS) system to determine perpendicular distance(s) from a DAS sensing fiber to vibration sources said method comprising:
operating the DAS system to measure baseline vibration levels and event characteristics at different perpendicular distances from locations along a length of sensing optical fiber that is part of the DAS system and collect a training dataset to establish canonical joint probability distribution of perpendicular distances from the sensing optical fiber and observed intensity;
integrating the measured baseline vibration levels and respective perpendicular distances from locations along the length of the sensing optical fiber to a geographic map;
generating a database of vibration intensity profiles for each perpendicular distance and location along the length of the sensing optical fiber;
determining background traffic vibrations in the database of vibration intensity profiles and removing same according to a median filtering methodology;
detecting a vibration through the effect of the DAS and determining a perpendicular distance from the sensing optical fiber of a source of the detected vibration; and
wherein the perpendicular distance determination is made from a DFOS stream of waterfall plots resulting from operation of the DAS system;
wherein the perpendicular distance determination includes an image binarization of the stream of waterfall plots; and
wherein the perpendicular distance determination includes generating an intensity profile at each perpendicular location using a join probability map by a Kernel Density or Gaussian Process Regression (GPR) process.

### Claim 2 (depends on 1)

The method of claim 1, further comprising generating and outputting an alarm when the determined perpendicular distance satisfies a pre-determined alarm threshold condition.