Time domain reflectometry of glass beads/magnetite mixtures: A time and frequency domain study

摘要

The measurements of the time domain reflectometry (TDR) signal propagating along a coaxial probe, filled with dry mixtures of glass beads and magnetite, are analyzed for deriving the attenuation factor α and the bandwidth. Samples with different percentages (5%-25%) of magnetite are considered. The α values are obtained by two different methods: (ⅰ) wave amplitude at the second reflection, (ⅱ) electromagnetic parameters and widths of the passing bands. The two methods provide consistent α values within the experimental uncertainties. The agreement supports the possibility of measuring the attenuation factor from the second TDR reflection, for anhydrous samples similar to the investigated mixtures.