Modelling of electromagnetic wave propagation along transmission lines in inhomogeneous media

Time domain reflectometry (TDR) is a well-established method for the measurement of moisture in various materials, especially soils. Standard waveform analysis usually provides the average water content along the length of the TDR probe, while more sophisticated methods are required to reconstruct the spatial water content profile. A reconstruction algorithm has been developed which uses one- or two-sided reflection data to calculate capacitance and conductivity distributions from which water content profiles can be derived. Several examples demonstrate the performance of the algorithm under various conditions in lossless and lossy materials.