Microwave scattering by rough polyhedral particles on a surface

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Virkki, Anne, Yurkin, Maxim
Formato: Preprint
Publicado: 2025
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866910063840460800
author Virkki, Anne
Yurkin, Maxim
author_facet Virkki, Anne
Yurkin, Maxim
contents The electromagnetic (EM) scattering by non-symmetric wavelength-scale particles on a planar surface has numerous applications in the remote sensing of planetary bodies, both in planetary and geo-sciences. We conduct numerical simulations of EM scattering by rough polyhedral particles (with 12 or 20 faces) using the discrete-dipole approximation and contrast the results to that of spheres. The particles have permittivities corresponding to common minerals in the microwave regime ($ε_r=4.7 + 0.016$i and $7.8 + 0.09$i), and a size-frequency distribution (SFD) consistent with the observed scattering properties (power-law distribution of size parameters between 0.5 and 8 with an index from $-2.5$ to $-3.5$). The assumed substrate permittivity $2.4 + 0.012$i corresponds to a powdered regolith. We present what roles the particle roundness, permittivity, and SFD for a realistic range of parameters play in the EM scattering properties as a function of incidence angle with a focus on backscattering in microwave-remote-sensing applications. The particle roundness and SFD have a clearly observable effect on the polarimetric properties, while the role of permittivity is relatively minor (in the studied range). Among various backscattering observables, the circular polarization ratio is the least sensitive to the decrease of the upper boundary (down to a size parameter of 3) and the index of the SFD.
format Preprint
id arxiv_https___arxiv_org_abs_2501_10019
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Microwave scattering by rough polyhedral particles on a surface
Virkki, Anne
Yurkin, Maxim
Earth and Planetary Astrophysics
Materials Science
The electromagnetic (EM) scattering by non-symmetric wavelength-scale particles on a planar surface has numerous applications in the remote sensing of planetary bodies, both in planetary and geo-sciences. We conduct numerical simulations of EM scattering by rough polyhedral particles (with 12 or 20 faces) using the discrete-dipole approximation and contrast the results to that of spheres. The particles have permittivities corresponding to common minerals in the microwave regime ($ε_r=4.7 + 0.016$i and $7.8 + 0.09$i), and a size-frequency distribution (SFD) consistent with the observed scattering properties (power-law distribution of size parameters between 0.5 and 8 with an index from $-2.5$ to $-3.5$). The assumed substrate permittivity $2.4 + 0.012$i corresponds to a powdered regolith. We present what roles the particle roundness, permittivity, and SFD for a realistic range of parameters play in the EM scattering properties as a function of incidence angle with a focus on backscattering in microwave-remote-sensing applications. The particle roundness and SFD have a clearly observable effect on the polarimetric properties, while the role of permittivity is relatively minor (in the studied range). Among various backscattering observables, the circular polarization ratio is the least sensitive to the decrease of the upper boundary (down to a size parameter of 3) and the index of the SFD.
title Microwave scattering by rough polyhedral particles on a surface
topic Earth and Planetary Astrophysics
Materials Science
url https://arxiv.org/abs/2501.10019