Sensor for High-Air-Humidity Measurement

  • V. Matko
  • D. Donlagic


The humidity sensor using the sensitive capacitive-dependent crystal is described. Presented is the probe sensitivity (dependence of df on the dCx). In addition, the new idea of excitation of the entire humidity sensor with stochastic test signals is described, and the humidity surface-measuring method is given. It includes the influence of test signals on the weighting function uncertainty and on the A/D-D/A conversion. The results of humidity measurement with the excitation signals are shown experimentally. The uncertainty of the surface humidity measurement is less than 0.2% (T=15–25°C and humidity = 50 to 98%).


Sensor Probe Humidity Sensor Excitation Signal Open Capacitor Humidity Measurement 
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Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  • V. Matko
    • 1
  • D. Donlagic
    • 1
  1. 1.Faculty of Electrical Engineering and Computer ScienceUniversity of MariborMariborSlovenia

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