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IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 42, NO. 8, AUGUST 2004

Fig. 10.

distribution (oscillating curves) derived from the two-layer scattering model for three permittivities. (a)

, (b)

, and (c)

. The smooth black curves on (a)­(c) represent the average

. Results are computed for

. (d) Maximum value of

with respect to the roughness  of the paleosoil and for each permittivity value. Finally, (e) compares the average

(smooth black curves on

the first three figures) for each permittivity.

We computed

values for a sand layer thickness

corresponding to the

sidered an incidence angle of

ranging from 0­6 m by 4.10  -m steps with a sand permittivity

RAMSES local incidence angle on the Pyla dune. Because of

and for three values of permittivity corre-

a noninfinitesimal increment step in the sand layer thickness,

sponding to three different water content of the paleosoil: 10%

(10) leads to strong phase variations as shown in Fig. 10(a)­(c).

, Fig. 10(a)], 12% [

,

profile for

[

We, thus, need to calculate an average

, Fig. 10(c)]. We con-

Fig. 10(b)], and 17% [

each permittivity [smooth black curves in Fig. 10(a)­(c)]: these