A Robust Serial FBG Sensor Network with CDM Interrogation Allowing Overlapping Spectra

Marek Götten, Marek Götten, Steffen Lochmann, Andreas Ahrens, César Benavente-Peces

2020

Abstract

Massive optical sensor networks gained a lot of attention in recent years. They offer new advances in the fields of smart structures and health monitoring. All serial optical sensor networks rely on multiplexing techniques that provide huge amounts of sensors in a single optical fiber. Wavelength-division multiplex (WDM) which has been established in many applications, is restricted to the spectral width of the used light source that needs to be shared by several non-overlapping fiber-Bragg-grating (FBG) spectra. Time-division multiplex (TDM) uses short impulses and relies on different sensor round trip delays to distinguish each single FBG. These short impulses and long round trip times lead to a low signal-to-noise ratio (SNR). Optical frequency-domain reflectometry (OFDR) offers a high spatial resolution of FBGs but only within a short fiber length. This contribution deals with a code-division multiplex (CDM) interrogation technique that provides numerous sensors in a single optical fiber, a better SNR, and a long range of distributed sensing points. It requires codes with good autocorrelation behavior which is characterized by certain criteria. The detectable criteria are limited which narrows significantly a search for best possible codes for the interrogation system. In this contribution, practical implementation limits such as the trigger timing and the achievable SNR are studied. Based on the introduced SNR definitions for CDM and WDM systems, a direct comparison is possible and it shows the superiority of the proposed CDM scheme. A network with 25 sensors operating at the same wavelength can provide a 2.67 dB improvement compared to WDM

Paper Citation

in Harvard Style

Götten M., Lochmann S., Ahrens A. and Benavente-Peces C. (2020). A Robust Serial FBG Sensor Network with CDM Interrogation Allowing Overlapping Spectra. In Proceedings of the 9th International Conference on Sensor Networks - Volume 1: SENSORNETS, ISBN 978-989-758-403-9, pages 23-28. DOI: 10.5220/0008942900230028

in Bibtex Style

@conference{sensornets20,
author={Marek Götten and Steffen Lochmann and Andreas Ahrens and César Benavente-Peces},
title={A Robust Serial FBG Sensor Network with CDM Interrogation Allowing Overlapping Spectra},
booktitle={Proceedings of the 9th International Conference on Sensor Networks - Volume 1: SENSORNETS,},
year={2020},
pages={23-28},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0008942900230028},
isbn={978-989-758-403-9},
}

in EndNote Style

TY - CONF

JO - Proceedings of the 9th International Conference on Sensor Networks - Volume 1: SENSORNETS,
TI - A Robust Serial FBG Sensor Network with CDM Interrogation Allowing Overlapping Spectra
SN - 978-989-758-403-9
AU - Götten M.
AU - Lochmann S.
AU - Ahrens A.
AU - Benavente-Peces C.
PY - 2020
SP - 23
EP - 28
DO - 10.5220/0008942900230028