Spatial and frequency averaging techniques for a polarimetric scatterometer system

Author

Monakov, Andrei A. ; Vivekanandan, J. ; Stjernman, Anders S. ; Nystrom, Anders K.

Author_Institution

Swedish Inst. of Space Phys., Kiruna, Sweden

Volume

32

Issue

1

fYear

1994

fDate

1/1/1994 12:00:00 AM

Firstpage

187

Lastpage

196

Abstract

Radar scattering signals from distributed targets exhibit fading due to interference associated with coherent scattering from individual scatterers within the resolution volume. Uncertainty in radar measurements which arises as a result of fading is reduced by averaging independent samples. Independent samples are obtained by collecting the radar returns from nonoverlapping footprints (spatial averaging) and/or nonoverlapping frequencies (frequency agility techniques). An improved formulation of fading characteristics for the spatial averaging and frequency agility technique is derived by taking into account the rough surface scattering process. Kirchhoff´s approximation is used to describe rough surface scattering. Expressions for fading decorrelation distance and decorrelation bandwidth are derived. Rough surface scattering measurements are performed between L and S bands. Measured frequency and spatial correlation coefficients show good agreement with theoretical results

Keywords

backscatter; frequency agility; geophysical techniques; polarimetry; radar cross-sections; remote sensing; remote sensing by radar; Kirchhoff´s approximation; UHF SHF microwave; backscatter; decorrelation bandwidth; decorrelation distance; distributed target; frequency agility; frequency averaging; geophysical measurement technique; interference; mapping imaging; nonoverlapping footprints; nonoverlapping frequencies; polarimetric scatterometer; radar remote sensing; radar return; rough surface scattering process; scattering signal; spatial averaging; Decorrelation; Fading; Frequency; Interference; Radar measurements; Radar scattering; Rough surfaces; Signal resolution; Spatial resolution; Surface roughness;

fLanguage

English

Journal_Title

Geoscience and Remote Sensing, IEEE Transactions on

Publisher

ieee

ISSN

0196-2892

Type

jour

DOI

10.1109/36.285201

Filename

285201