Continuing with the Fresnel database: experimental setup and improvements in 3D scattering measurements

In this paper, the experimental setup and the improvements required to obtain further measurements for the third opus of the Fresnel Database are presented. The most original feature of those new datasets is the fact that they were obtained with three-dimensional targets instead of the two-dimensional ones used in the two previous opuses. The measurements were performed all around the targets under test to collect enough information about the objects to be able to perform inversion on their scattered fields. As the targets were small in comparison with the wavelength, the challenge here was to extract these small scattered fields from the measurements, and a specific post-processing procedure had to be designed to compensate for the drift errors. The five targets selected for the database are presented, including the Myster target, a hitherto undivulged target that is presented in this paper for the first time, i.e., at the same time as the submissions of all the other contributors to this special section. Some scattered field comparisons are also presented.