Wideband extinction measurements for thin and planar samples

This paper describes a method to accurately determine the extinction cross section and the extinction volume for a thin and planar object over a large frequency interval in the microwave region. The method is based on a conventional measurement of the monostatic radar cross section (RCS) and it is compared to and validated with a more general method based on the RCS in the forward direction. The experiments are performed on a fabricated single-layer planar array of split ring resonators (SRR). The motivation for this study is to develop methods that can be used to verify a general summation rule for the extinction cross section that bounds the overall scattering and absorption properties of a target.