Frequency Domain Analyses of TDR Waveforms for Soil Moisture Measurements

C002 FREQUENCY DOMAIN ANALYSES OF TDR Abstract WAVEFORMS FOR SOIL MOISTURE MEASUREMENTS 1 When time domain reflectometry (TDR) is applied to the field characterization of soil moisture the waveforms have typically been analyzed using traveltime along the waveguide. The apparent dielectric constant (Ka) traditionally determined by the traveltime analysis using a tangent-line method does not have a clear physical meaning and is influenced by several system and material parameters. The frequency domain analysis however can determine the actual frequency-dependent dielectric permittivity and can be performed using a very short probe. The primary objectives of this paper are to (1) examine