7.1.3 - Physics-Based Dynamic Estimation of NO₂ and H₂O Concentrations with CNT-FETs and Extended Kalman Filter
- Event
- EUROSENSORS 2026
2026-09-06 - 2026-09-09
Zurich - Band
- Lectures
- Chapter
- Chemical Sensors
- Author(s)
- C. Gentili, C. I. Roman, I. Kraiem, M. Haluska, C. Hierold - ETH Zürich,Zürich (Switzerland)
- Pages
- 224 - 225
- DOI
- 10.5162/eurosensors2026/7.1.3
- ISBN
- 978-3-910600-12-6
- Price
- free
Abstract
We present a Langmuir-based Extended Kalman Filter (EKF) framework for real-time estimation of NO 2 at ppb-level concentrations in humid air at room temperature. Two CNT-FETs gas sensors were exposed to a gas-mixture experiment involving different NO 2 and humidity (H 2 O) concentrations, with threshold voltages (V T ) extracted from sensors transfer characteristics over time. The V T signals were first fitted using a two-gas Langmuir isotherm-based model; next, an Extended Kalman Filter (EKF) enabled dynamic NO 2 and H 2 O simultaneous estimation.