Title :
Sensor for high-air-humidity measurement
Author :
Matko, V. ; Donlagic, D.
Abstract :
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 of the weighting function uncertainty and of 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 to 25/spl deg/C and humidity=50 to 98%).
Keywords :
analogue-digital conversion; capacitance measurement; digital-analogue conversion; electric sensing devices; humidity measurement; A/D-D/A conversion; excitation signals; high-air-humidity measurement; humidity sensor; humidity surface-measuring method; probe sensitivity; sensitive capacitive-dependent crystal; stochastic test signals; test signals; weighting function uncertainty; Capacitance measurement; Capacitive sensors; Equations; Frequency; Humidity measurement; Oscillators; Probes; Pulse width modulation; Stability; Temperature sensors;
Conference_Titel :
Precision Electromagnetic Measurements Digest, 1996 Conference on
Conference_Location :
Braunschweig, Germany
Print_ISBN :
0-7803-3376-4
DOI :
10.1109/CPEM.1996.547110
