A T-Matrix Based Plant Stem Model for Inverse Scattering Applications

An efficient method to calculate the azimuthal monostatic radar cross section (RCS) of a plant stem is proposed. The method is based on the recursive aggregated centered T-matrix algorithm (RACTMA) which allows to efficiently calculate the T-matrix of a cluster of scatterers mimicking the internal structure of the plant stem. Due to the high efficiency of the method, it is suitable for the inverse scattering analysis to determine geometrical and material parameters of the internal structure of a plant stem. The method's efficiency and accuracy are demonstrated by the retrieval of unknown geometrical and material parameters, influenced by fabrication tolerances, from monostatic RCS measurements of a 3D-printed mockup of a plant stem. The measurement is conducted for TM polarization at frequencies ranging from 110 GHz to 170 GHz.