Aucun titre de diapositive

1
Modèle d'architecture d'arbre Atelier de
Modélisation de l'Architecture des Plantes,
CIRAD - analyse de l'architecture de la plante. -
calibration par site à partir de mesures sur le
terrain. - simulations -gt maquettes (ensemble de
cylindres).
Apport Description détaillée des
diffuseurs. Prise en compte de la variabilité
verticale.
Âge (année)
2
Interface AMAP/RT (AMAP2SAR)
Inputs of the e.m models

• Scatterers density (per layer)
• Geometric description
• Surface roughness
• Moisture (ground, vegetation)
• Acquisition parameters (f,p,i)

EM MODELS (CESBIO)
AMAP MODEL (Cirad)

• Model outputs
• backscatter values
• scattering mechanisms
• contribution of scatterers

3
Comparison RT-3D modelling and X-band HUTSCAT
measurements

• Good agreement
• Penetration depth seems to be of several meters

4
Inversion into foliar biomass (LAI) Comparison
for the 40-year old Austrian pine stand
18
16
14
12
10
Height above the ground (m)
8
6
4
In-situ LAI
2
Radar retrieved LAI
0
0
0.25
0.5
0.75
1
1.25
LAI (m²/m²)
5
Distorted Born approximation applied to the
modelling of forest scattering
horizontal, homogeneous layers to compute (Foldy
approximation)
6
2D vs 3D modelling for single pass interferometry
3D
2D
Interferometric height
Interferometric height
Phase centre
7
Height retrieval using single pass
interferometry 2D-3D Born approximation
modelling
X Band SRTM configuration
C Band ERS-like configuration
Lozere forest Corsican pine
8
Picard G., T. Le Toan, S. Quegan,(2004) A
Three-Dimensional Radiative Transfer Model
applied to ranging scatterometer measurements
from a pine forest Waves in Random Media, 14
(2004), 317-331. Picard G., T. Le Toan, S.
Quegan, Y. Cariglio, (2004). Radiative Transfer
modeling of cross-polarised backscatter from a
pine forest using the discrete ordinate and
eigenvalue method , IEEE Transactions on
Geoscience and Remote Sensing,Vol 42, no 8,
pp1720-1730. Castel T., A. Beaudoin, N.
Floury, T. Le Toan, Barczi J.F., and Caraglio
Y., "Deriving Forest Parameters for Backscatter
Models Using the AMAP Architectural Plant
Model", IEEE Transactions on Geoscience and
Remote Sensing, 2000. Martinez J.M., N.
Floury, T. Le Toan, A. Beaudoin, M.T.
Hallikainen, and M. Makynen." Measurements and
modelling of vertical backscatter distribution
in forest canopy", IEEE Transactions on
Geoscience and Remote Sensing, vol. 38, no 2,
710-719, March 2000 Melon P., Martinez JM, T.
Le Toan, L. Ulander, A. Beaudoin, "On the
retrieving of Forest stem volume from VHF SAR
data" , IEEE Transactions on Geoscience and
Remote Sensing, November 2001.