Measurement strategies for a confined microwave circular scanner

International audience This article deals with the inverse scattering problem from scattered field data measured inside a closed microwave scanner. This system is presently being developed to demonstrate the potentiality of a non-invasive microwave imaging system for volumetric water content monitoring. The final goal is to retrieve soil moisture information as it is an important parameter for understanding fluid flow modelling, as well as water uptake by plants roots. Based on the actual state of the setup, we are proposing appropriate numerical tools, in particular a finite element formalism combined with a Lagrangian minimization scheme to provide a fast and accurate imaging tool. We will also show how we can improve the reconstruction algorithms by changing in a very simpler manner the measurement configuration, using either off-centred information or impedance boundary matching environment.