Source Separation Using Sensor’s Frequency Response: Theory and Practice on Carbon Nanotubes Sensors

• Main Authors: Aurore Quelennec, Éric Duchesne, Hélène Frémont, Dominique Drouin
• Format: Article
• Language: English
• Published: MDPI AG 2019-08-01
• Series: Sensors
• Subjects: MWCNT; source separation; dual sensor; temperature sensor; moisture sensor; gas sensor; sensing mechanism
• Online Access: https://www.mdpi.com/1424-8220/19/15/3389

Nowadays, there is an increased demand in integrated sensors for electronic devices. Multi-functional sensors provide the same amount of data using fewer sensors. Carbon nanotubes are non-selectively sensitive to temperature, gas and strain. Thus, carbon nanotubes are perfect candidates to design multi-functional sensors. In our study, we are interested in a dual humidity-temperature sensor. Here, we present a novel method to differentiate at least two sources using the sensor’s frequency responses based on multiwall carbon nanotubes sensors. The experimental results demonstrate that there are temperature- or moisture-invariant frequencies of the impedance magnitude, and their values depend on the sensor’s geometry. The proposed measurement model shows that source-invariant frequencies of the phase can be also determined. In addition, the source separation method is generalized to other materials or sources enabling multi-functional sensors for environment monitoring.