FDTD based vegetation simulation - application to multiple wavelengths and vegetation species

Abstract

This paper presents a novel technique for full-wave numerical modelling of radar backscatter from vegetation canopies using the Finite Difference Time Domain (FDTD) approach. Multitude of simulation techniques exist for estimating the backscatter from vegetation canopies including analytical techniques and numerical approaches such as FEM and MOM(via commercial products such as HFSS and FEKO). The approach presented here uses the MEEP[1] simulator in parallel mode to efficiently calculate the fields over a time interval using a set of stochastically generated vegetation structures of different species and ground surface with 2 different orders of roughness. The vegetation is modelled using a modification of Ulaby's water cloud model since water is the dominant material in the vegetation-microwave interaction. This approach shows promise in both numerical field strength estimation and intuitive understanding of microwave propagation in complex vegetation like medium.