Microwave measurements of the full amplitude scattering matrix of a complex aggregate: a database for the assessment of light scattering codes

Abstract

We present an extensive experimental study of microwave scattering by a fully characterized complex aggregate. We measured the full amplitude scattering matrix (amplitude and phase of the four elements) for a wide range of configurations. The presented results are of special interest to the light scattering community. Our experiments offer the possibility to validate numerical methods against experiments, since the geometrical and dielectric properties of the complex target are known to a high degree of precision, a situation difficult to attain in the optical regime. We analyze in detail the behaviour of amplitude and phase as a function of the scattering angle and target orientation. Furthermore, we compare different computational methods for a specific experimental configuration.

A large 3D target with small inner details: A difficult cocktail for imaging purposes without a priori knowledge on the scatterers geometry

“…The first step consists in defining a careful alignment procedure as the challenge is to place this very small target (85 mm) in the middle of our 4000 mm diameter measurement sphere. This was realized with the help of small transparent spheres and the help of a laser beam [ Merchiers et al , 2010]. We have then checked that this procedure allows placing the target at the right position.…”

“…The computation complexity is then of O ( NlogN ) and the memory requirement is O ( N ). More details on this algorithm can be found in the work by Merchiers et al [2010].…”

A Rigorous Forest Scattering Model Validation Through Comparison With Indoor Bistatic Scattering Measurements

“…To reference the module and phase of the experimental scattered field, a calibration using a reference target was applied [23]. The theoretical scattered field of the reference target must be accurately known.…”

Full wave analysis of VHF-UHF forest bistatic scattering mechanisms an investigation on the influence of electromagnetic coupling

“…We start by measuring the total field in order not to move the circular plate by putting the targets on it. To compare measured and simulated scattered fields, we have calibrated the measurement data to obtain the same reference as the simulations results with the method described in [6]. The amplitude of the incident field is then normalized to the unity and the phase is null at the centre of the circular plate.…”