A coherent scattering model to determine forest backscattering in the VHF-band

Author

Israelsson, Hans ; Ulander, Lars M H ; Martin, Torleif ; Askne, Jan I H

Author_Institution

Dept. of Radio & Space Sci., Chalmers Univ. of Technol., Goteborg, Sweden

Volume

38

Issue

1

fYear

2000

fDate

1/1/2000 12:00:00 AM

Firstpage

238

Lastpage

248

Abstract

A coherent scattering model to determine the forest radar backscattering at VHF frequencies (20-90 MHz) has been developed. The motivation for studying this frequency band is the recent development of the CARABAS Synthetic Aperture Radar (SAR). In order to model the scattering from branches and trunks, homogeneous dielectric cylinders placed above a semi-infinite di-electric ground have been analyzed. An analytical approach, where the theoretically exact currents induced in an infinite cylinder are truncated, has been compared to a numerical solution using the finite difference time domain (FDTD) method. If the first-order coherent ray tracing is included in the analytical approach, the results match well with the numerically exact FDTD solution. The results show that, in order to determine the VHF-backscattering from a forest stand, the coherent ground interaction is an important part and has to be considered. In this paper, modeling results are in good agreement with CARABAS measurements

Keywords

backscatter; forestry; geophysical techniques; radar cross-sections; radar theory; remote sensing by radar; synthetic aperture radar; vegetation mapping; 20 to 90 MHz; CARABAS; HF; SAR; VHF; analytical approach; backscatter; backscattering; branch; coherent scattering model; finite difference time domain; forest; forestry; geophysical measurement technique; homogeneous dielectric cylinder; radar remote sensing; radar scattering; synthetic aperture radar; trunk; vegetation mapping; Backscatter; Biomass; Dielectrics; Finite difference methods; Frequency; Radar scattering; Space technology; Spaceborne radar; Synthetic aperture radar; Time domain analysis;

fLanguage

English

Journal_Title

Geoscience and Remote Sensing, IEEE Transactions on

Publisher

ieee

ISSN

0196-2892

Type

jour

DOI

10.1109/36.823916

Filename

823916