Numerical Backscattering Analysis for Rough Surfaces Including a Cloddy Structure

• Published in: IEEE transactions on geoscience and remote sensing Vol. 48; no. 5; pp. 2367 - 2374
• Main Authors: Zribi, Mehrez, Le Morvan-Quemener, Aurelie, Dechambre, Monique, Baghdadi, Nicolas
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.05.2010; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Agricultural sciences; Applied geophysics; Backscatter; Backscattering; Earth Sciences; Earth, ocean, space; Electromagnetic modeling; Electromagnetism; Engineering Sciences; Exact sciences and technology; Integral equations; Internal geophysics; Length measurement; Life Sciences; modeling; Radar; Rough surfaces; roughness; Scanning probe microscopy; Sciences of the Universe; Soil measurements; Surface fitting; Surface roughness; Triticum aestivum; models; modeling; correlation; roughness; soils; radar methods; backscattering; tillage; correlation function; frequency; MOISTURE; BARE SURFACES; INTEGRAL-EQUATION MODEL; PARAMETERIZATION; SAR; IEM MODEL; SIMULATION; SCATTERING; SOIL ROUGHNESS; RADAR DATA
• ISSN: 0196-2892; 1558-0644
• DOI: 10.1109/TGRS.2009.2038710

In recent years, the presence of a new type of agricultural-surface tillage used for the sowing of wheat and corn has been observed with increasing frequency. It illustrates less roughly ploughed soils, with a greater quantity of small clods distributed over the soil surface. In this paper, a new description of such rough agricultural surfaces is proposed. It is based on a composite model, including a classical surface represented by an exponential correlation function, together with a random cloddy structure. This description enables volumetric structures to be introduced over the soil's surface. A numerical moment-modeling method, based on integral equations, is used to evaluate the contribution of clods to the radar backscattering behavior of agricultural surfaces. It is found that the presence of clods explains the very small correlation lengths which are often found in cloddy agricultural fields. The classical approach, in which the surface is described by a correlation function only based on two statistical parameters, rms height and correlation length, overestimates the backscattering coefficients when compared with an approach that includes the clods. This overestimation is often observed with real radar data for such fields.