Title :
A Miniaturized Resonant Moisture Sensor
Author :
Jannsen, Bert ; Jacob, Arne F.
Author_Institution :
Institut fÿr Hochfrequenztechnik, Technische Universitÿt Braunschweig, P.O. Box 3329, 38023 Braunschweig, FR Germany. Phone:+49 531 2012, Fax.: +49 531 391 2045, e-mail: b.jannsen@tu-bs.de
Abstract :
A novel and very compact resonant sensor is presented. It consists of a resonant metallic helix mounted in a circular waveguide which is operated below cutoff. The resonance frequency is easily adjustable via the helix dimensions. A material sensitive to the environmental properties to be detected is placed next to the helix and alters its resonance. Design and optimization of the sensor are reported with an emphasis on moisture detection. Its application in civil engineering is demonstrated with measurements of the moisture content of cement.
Keywords :
Building materials; Chemical sensors; Civil engineering; Concrete; Condition monitoring; Electromagnetic waveguides; Moisture measurement; Permittivity measurement; Resonance; Resonant frequency;
Conference_Titel :
Microwave Conference, 2001. 31st European
Conference_Location :
London, England
DOI :
10.1109/EUMA.2001.339096
