Simplificaiton Of Linear Short-Gravity Waves For Modeling Sea Clutter Returns Due To Bragg Scattering At X Band

The Bragg hypothesis provides a simplified representation of the complex real ripples that contribute to sea clutter returns. We propose to describe the microscopic profile of large-scale long waves by a set of sinusoidal ripples, which are assumed to be with the Bragg wavelength that satisfies the resonant condition, and travel along the local scattering lines of sight pointing towards and away from the radar. This simplification shows a reasonable way to obtain a rather simple representation of Bragg waves on sea surfaces. More importantly, it allows us to derive a simple asymptotic expression of integration in the far-field scattering amplitude formula, which facilitates the development on a compact model of the instantaneous complex reflective function of a time-deterministic sea surface. Good agreements shown in numerical examples validate the proposed model, which is very efficient to simulate the coherent sea clutters in 2D case up to X band.