Radiative transfer model for microwave bistatic scattering from forest canopies

• Published in: IEEE transactions on geoscience and remote sensing 2005-11, Vol.43 (11), p.2470-2483
• Main Authors: Pan Liang, Pierce, L.E., Moghaddam, M.
• Format: Article
• Language: English
• Subjects: Animal, plant and microbial ecology; Applied geophysics; Backscatter; Biological and medical sciences; Biomass; Bistatic radar; Bistatic scattering; Earth sciences; Earth, ocean, space; Exact sciences and technology; forest scattering; Fundamental and applied biological sciences. Psychology; General aspects. Techniques; Information geometry; Internal geophysics; Microwave theory and techniques; Permittivity; Radar polarimetry; Radar scattering; Radar systems; radiative transfer; Scattering parameters; Shape; synthetic aperture radar (SAR); Teledetection and vegetation maps
• ISSN: 0196-2892; 1558-0644
• DOI: 10.1109/TGRS.2005.853926

A bistatic forest scattering model is developed to simulate scattering coefficients from forest canopies. The model is based on the Michigan Microwave Canopy Scattering (MIMICS) model (hence called Bi-MIMICS) and uses radiative transfer theory, where the first-order fully polarimetric transformation matrix is used. Bistatic radar systems offer advantages over monostatic radar systems because of the additional information provided by the diversity of the geometry. By simulating the forest canopy scattering from multiple viewpoints, we can better understand how the forest scatterers' shape, orientation, density, and permittivity affect the canopy scattering. Bi-MIMICS is parametrized using selected forest stands with different canopy compositions and structure. The simulation results show that bistatic scattering is more sensitive to forest biomass changes than backscattering. Analyzing scattering contributions from different parts of the canopy gives us a better understanding of the microwave's interaction with the tree components. The ground effects can also be studied. Knowledge of the canopy's bistatic scattering behavior combined with additional synthetic aperture radar measurements can be used to improve forest parameter retrievals. The simulation results of the model provide the required information for the design of future bistatic radar systems for forest sensing applications.