Imaging using the transverse field of a parallel transmission line

The transverse field resulting from a pulse propagating along a parallel transmission line can be used to image changes in the dielectric permittivity of material samples adjacent to it. This Time Domain Reflectometry approach enables a non-contact probe to be rapidly scanned across surfaces such as roads, timber and concrete to determine the subsurface moisture content. Two examples of applying this probe - timber processing and road maintenance - in industrial applications are presented.