Comparison Between Microwave Emissivity And Backscattering Coefficient Of Agricultural Fields

L-Band Passive and Active Signatures of Vegetated Soil: Simulations With a Unified Model

“…Experimental data from both airborne and satellite acquisitions confirm the theoretical expectations formulated in [18] and [21]. Both simulated and experimental results display a trianglelike shape in the σ 0 versus e feature space, with triangle vertices associated with the cases of dry surface, wet surface, and volume scattering, respectively.…”

“…In particular, for several vegetation species and for an angle higher than about 30°, an increase in soil roughness or vegetation biomass produces an increase in both the emissivity and the backscattering coefficient [18]- [20], while an increase in SM produces an increase in the backscattering coefficient and a decrease in the emissivity, whatever the roughness [20]. A physical interpretation of this result, given in [18], is based on the relationships between backscattering coefficient, emissivity, and bistatic scattering coefficient. More recently, it was suggested that, in the σ 0 versus e plane, an ideal triangle can be traced, with the three vertices corresponding to the emission and backscattering of a dry surface, a wet surface, and vegetation volume [21].…”

“…In this paper, the theoretical formulation already proposed in [18] and [21] is applied in order to simulate backscattering coefficient and emissivity of bare soils, growing maize crops and broadleaf forests under various values of SM. The advantage of this approach is that a sole physical formulation is adopted to compute the bistatic scattering coefficient of the observed medium.…”

“…In the past, several works demonstrated that the emissivity e and the backscattering coefficient σ 0 of land surfaces are affected in different ways by soil and vegetation variables [18], [19]. In particular, for several vegetation species and for an angle higher than about 30°, an increase in soil roughness or vegetation biomass produces an increase in both the emissivity and the backscattering coefficient [18]- [20], while an increase in SM produces an increase in the backscattering coefficient and a decrease in the emissivity, whatever the roughness [20].…”

“…The advantage of this approach is that a sole physical formulation is adopted to compute the bistatic scattering coefficient of the observed medium. Backscattering coefficient and emissivity are computed using the procedure described in [18].…”