1. N. Pierdicca 1 , L. Guerriero 2 , R. Giusto 1 , M. Brogioni 3 , A. Egido 4 , N. Floury 5 1 DIET - Sapienza Univ. of Rome, Rome, Italy 2 DISP - University of Tor Vergata, Rome, Italy 3 CNR/IFAC, Sesto Fiorentino. Italy 4 Starlab, Barcelona, Spain 5 ESA/ESTEC, Noordwyik, The Netherland GNSS Reflection from Bare and Vegetated Soils: Experimental Validation of an End-to-end Simulator

4. The LEIMON experiment FDR and TDR soil moisture probes Meteo station Soil roughness profilometer Bare (different roughness) and vegetated fields Plant height and water content

5. Time serie overview West field with developed plants

6. |Y | 2 Processed signal power at the receiver vs. delay   and frequency f . P T The transmitted power of the GPS satellite. G T , G R The antenna gains of the transmitting and the receiving instrument. R R , R T The distance from target on the surface to receiving and transmitting antennas. T i The coherent integration time used in signal processing.  Bistatic scattering coefficient  2 The GPS correlation (triangle) function S 2 The attenuation sinc function due to Doppler misalignment dA Differential area within scattering surface area A (the glistening zone). The mean power of received signal vs. delay  and frequency f is modeled by integral Bistatic Radar Equation which includes time delay domain response    ’  and Doppler domain response S 2 ( f’-f ) of the system (Zavorotny and Voronovich, 2000). The Bistatic Radar Equation

9.  ° electromagnetic modelling Indefinite mean surface plane with roughness at wavelength scale. Bistatic scattering of locally incident plane waves by AIEM Homogeneous vegetation cover. Attenuation and multiple scattering by a discrete medium (Tor Vergata model) INCOHERENT component COHERENT component Scattering of spherical wave by Kirchoff approxi. (Eom & Fung, 1988) attenuated by vegetation

13. DDM output example DDM’s (delay on the horizontal axes, frequency on the vertical axes) for incoherent (top) and coherent (bottom) component at RHCP (left) and LHCP (right) Spaceborne incoherent airbone incoherent

21. Vegetation o verall comparison Fair correspondence between model and vegetation data (except for largest angle  =55°) June 28, July 10,28 22<SMC<18% PWC=1.2, 3.6, 6.7 kg/m 2

26. Thank you for your attention