# Three-Component Accelerometer Based on Distributed Optical Fiber Sensing

## TL;DR

A new three-component optical fiber accelerometer is developed for seismic wave detection, showing performance comparable to traditional electrical accelerometers.

## Contribution

A novel three-component optical fiber accelerometer using a distributed strain interrogator and reconstruction algorithm is proposed.

## Key findings

- The accelerometer achieved a correlation coefficient over 0.9 compared to an electrical accelerometer.
- The angular error in reconstructed acceleration was less than 8°.
- The device is compatible with distributed optical fiber sensing for long-distance seismic monitoring.

## Abstract

The three-component accelerometer array has garnered significant attention in seismic wave detection. In this paper, we designed a three-dimensional optical fiber accelerometer based on a circular cross-section cantilever beam and distributed optical fiber strain interrogator. An externally modulated optical frequency domian reflectometry (OFDR) system with centimeter-level spatial resolution is developed to demodulate the dynamic strain on fiber. An algorithm to reconstruct the three-component acceleration from the strain of the optical fiber was derived, and the factors affecting the errors in reconstruction were also investigated. The developed accelerometer exhibits comparable performance to an electrical accelerometer in the experiment. The correlation coefficient between the reconstructed signal waveforms from the two accelerometers exceeded 0.9, and the angular error was less than 8°. The proposed accelerometer is highly compatible with distributed optical fiber sensing technology, presenting significant potential for long-distance array deployment of three-component seismic wave monitoring.