# Static Thermal Model of a Fibre-Optic Rotational Seismometer

## TL;DR

This paper introduces a thermal model for a fibre-optic rotational seismometer to improve its accuracy by accounting for temperature effects.

## Contribution

The novel contribution is a compact static thermal model using a resistor network to accurately capture temperature effects in key device locations.

## Key findings

- A thermal resistor network model was developed to compute temperature values in critical parts of the seismometer.
- Accurate temperature estimation in fibre-optic loops improved the device's sensitivity.
- The model uses thermocouple measurements to estimate thermal element values.

## Abstract

Fibre-optic rotational seismometers are devices capable of high-accuracy measurements of rotation rates. Taking into account that temperature significantly influences their operation, particularly the optical signal path, accurate thermal models of these devices are required. This paper presents a static thermal model of such a fibre-optic rotational seismometer. This compact thermal model is based on a thermal resistor network, where the temperature values are computed only in the most important locations of the device. The values of thermal model elements are estimated based on thermocouple temperature measurements. Owing to the accurate determination of temperature values, especially in fibre-optic loops, it was possible to achieve the desired device sensitivity.