Two-dimensional Rough Sea Surface Research Articles

Study of electromagnetic scattering from two-dimensional rough sea surface based on improved Wen’s spectrum

By combining the improved Wen's spectrum with the classic Monte Carlo algorithm and Donelan's experimental conclusion, a two-dimensional sea surface model suitable for different depths and different stages of wave growth is proposed in this paper. Based on the classic two-scale method for the calculation of sea backscattering coefficient, and the introduction of the simulation results obtained by the SSA (small slope approximation) method, the electromagnetic scattering calculation method is modified. Compared with the fitting result based on the backscattering coefficient model of GIT, it proves that the improved Wen's spectrum is suitable for Chinese coastal waves, and the proposed electromagnetic scattering theory is accurate and efficient.

Bistatic scattering analysis for two-dimensional rough sea surfaces using an angular composite model

An angular composite model (ACM) is applied to analyse the bistatic scattering from two-dimensional sea surfaces. When the local scattered angle lies in the specular region, Kirchhoff approximation (KA) is used to evaluate the specular reflection, which predominates the total scattering in this region; the small perturbation method (SPM) is employed to deal with the diffuse reflection dominated by small roughness, as the local scattered angle is situated out of the specular region. This avoids dwelling on the tough question about how to choose the proper cut-off wave number like in the well-known two-scale model (TSM). Numerical illustrations are carried out for bistatic scattering coefficients versus wind speed, incident angle, incident frequency and polarization state, respectively. The comparison of numerical results of the ACM and other experimental and theoretical models in several configurations shows that the ACM is robust to give accurate numerical evaluations for bistatic scattering of rough sea surfaces.

An angular cutoff composite model for investigation on electromagnetic scattering from two-dimensional rough sea surfaces

Based on the local configuration angle division to select the corresponding method for electromagnetic scattering calculation from rough sea surface, this paper presents an angular cutoff composite model: when the local scattered angle is in the specular region that is given by an approximately 20 degrees cone around the specular direction, the Kirchhoff approximation is applied to evaluate the specular reflection, which dominates the total scattering in this region; the small perturbation method is employed to handle the diffuse reflection which is predominant as the local scattered angle is situated out of the specular region. Numerical results are compared with those of experimental and theoretical models in several configurations as a function of incident angle, wind speed, wind direction. The comparison of numerical results of other experimental and theoretical models in several configurations shows that the new composite model is robust to give accurate numerical evaluations for the sea surface scattering.

Study of Microwave Thermal Emission from Two-dimensional Rough Sea Surfaces

Study of Microwave Thermal Emission from Two-dimensional Rough Sea Surfaces