Modeling radar scatter from distributed targets using a coupled scatterer approach

Radar remote sensing deals with the extraction of object information from electromagnetic wave parameters. To fully exploit the potential of acquiring quantitative information requires a detailed description of the interaction between microwaves and objects. For practical reasons a simplified approach is preferred where the radar return of a distributed target is modeled as a sum of scatterer echoes. In this paper, a point scatterer model is given to simulate scattering of radar waves by distributed targets. The scatterers may have different heights in synthesizing rough surfaces. The principle of conservation of energy is used to account for electromagnetic coupling between the scatterers in function of target sampling density. The predicted coupling between two scatterers is experimentally verified by indoor radar cross section measurements. The model is verified through comparison with numerically solving the electric field integral equation for linear scatterer arrays. Results are given in the form of bistatic scatter diagrams to provide insight in the full scattering behavior.