Frequency-dependent Factor Expression of the GTD Scattering Center Model for the Arbitrary Multiple Scattering Mechanism

Abstract

This paper presents a derivation of a formula with a concise and uniform analytic form by the Stationary Phase Method (SPM) plus Geometrical Optics (GO), the Physical Theory of Diffraction (PTD), and Geometrical Theory of Diffraction (GTD) to calculate the frequency-dependent factor for the arbitrary multiple scattering mechanism, validated by the simulated and measured data of a series of canonical ensembles, validated by the simulated and measured data of a series of canonical ensembles. Although the GTD model, a scattering center model, can accurately describe the frequency-dependent characteristic of several main scattering mechanisms of the radar target, no explicit and general expression relates the frequency-dependent factor to the type of scattering mechanism. The derived formula relates the scattering center’s frequency-dependent factor with bounce times, dimensions of all the encountered geometrical elements, and a caustic type of ray contributing to the scattering center and can be applied to determine the parameter value of frequency-dependent factor of the GTD model and its derived versions in the forward parametric modeling.

Keywords

• scattering center model
• multiple scattering mechanism
• gtd model
• frequency-dependent factor