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Thesis (M.S.)—University of Nebraska—Lincoln, 1969. Department of Electrical Engineering.


Copyright 1969, the author. Used by permission.


Microwave refractometry provides a primary standard method for measuring the humidity of the air. The method has been used by several investigators to make measurements with accuracy better than 0.2% where the relative humidity is below about 80%. Stability of the measurements has been maintained over a period of weeks by some of the instruments. Accurate measurements of small variations in refractive index of air by this method have contributed to tropospheric radio propagation research.

Many different refractometers have been devised and several different methods of calibration have been used. It was observed, however, that appreciable deviation from the theoretical results occurred when high relative humidity was measured. The purpose of this experiment is to investigate this deviation. Successful extension of this method to the relative humidity range above 90% would be useful for investigators making plant life studies.

Advisor: A. R. Edison