Time domain gating for short circuited reflection measurements

Abstract

Moisture measurement of material based on Microwave reflection, in this case of concrete slabs, present a number of challenges in signal capture and processing. Multiple frequency measurements are needed to overcome phase ambiguity issues and isolation of the system response is necessary for accurate determination of bulk permittivity and hence volumetric moisture content. In this paper we describe data capture and processing such as pre and post transform data windowing and time-gate window functions. We also describe a method to optimise gate centring and gate width and apply this to experimental data.