Journal of Microwave Power and Electromagnetic Energy (JMPEE)
TITLE	Accurate Resonance Frequency Detection in a Microwave Moisture Measurement [PDF]
AUTHORS	S. Okamura, S. Miyagaki and Z. Ma 1998 33 3 143-150
YEAR
VOLUME
ISSUE
PAGES
Abstract This paper describes a technique for accurate resonance frequency detection of a moisture measurement system using a dielectric ring resonator operating at a center frequency of about 2.1 GHz by eliminating the influence of noise superimposing on the resonant curve. The curve fitting midpoint method is the most effective one among the three methods examined in this study. The cardboard samples with about 5 to 115% moisture on a dry basis were measured using the curve fitting midpoint method. The standard deviation of the predicted moisture contents is 1.14% (d.b.) over the whole range of moisture contents measured. Key Words: Resonator, Resonance frequency detection, Moisture content, Measurement, Curve fitting midpoint method