Semi-Empirical Calibration of the Integral Equation Model for Co-Polarized L-Band Backscattering

Remote Sensing

Nicolas Baghdadi²  Mehrez Zribi⁴  Simonetta Paloscia⁵  Niko E. C. Verhoest⁶  Hans Lievens⁶  Frederic Baup⁴  Francesco Mattia³  Ioannis Gitas¹  Josef Kellndorfer¹  Magaly Koch¹ 

[1] id="af1-remotesensing-07-13626">1IRSTEA, UMR TETIS, 500 rue François Breton, F-34093 Montpellier cedex 5, Fran;IRSTEA, UMR TETIS, 500 rue François Breton, F-34093 Montpellier cedex 5, France;CNR-ISSIA, via Amendola 122/D, Bari 70126, Italy; E-Mail:;CESBIO, 18 av. Edouard Belin, bpi 2801, 31401Toulouse cedex 9, France; E-Mails:;CNR-IFAC, via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze, Italy; E-Mail:;Laboratory of Hydrology and Water Management, Ghent University, Ghent B-9000, Belgium; E-Mails:

关键词: integral equation model;    synthetic aperture radar;    L-band;    bare soil;   

DOI  :  10.3390/rs71013626

来源: mdpi

【 摘 要 】

The objective of this paper is to extend the semi-empirical calibration of the backscattering Integral Equation Model (IEM) initially proposed for Synthetic Aperture Radar (SAR) data at C- and X-bands to SAR data at L-band. A large dataset of radar signal and in situ measurements (soil moisture and surface roughness) over bare soil surfaces were used. This dataset was collected over numerous agricultural study sites in France, Luxembourg, Belgium, Germany and Italy using various SAR sensors (AIRSAR, SIR-C, JERS-1, PALSAR-1, ESAR). Results showed slightly better simulations with exponential autocorrelation function than with Gaussian function and with HH than with VV. Using the exponential autocorrelation function, the mean difference between experimental data and Integral Equation Model (IEM) simulations is +0.4 dB in HH and −1.2 dB in VV with a Root Mean Square Error (RMSE) about 3.5 dB. In order to improve the modeling results of the IEM for a better use in the inversion of SAR data, a semi-empirical calibration of the IEM was performed at L-band in replacing the correlation length derived from field experiments by a fitting parameter. Better agreement was observed between the backscattering coefficient provided by the SAR and that simulated by the calibrated version of the IEM (RMSE about 2.2 dB).

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.