Impact of 3D model simplifications on the determination of numerical accuracy of the radar cross-section in aerial target recognition issues

Method of moments is one of the most useful approaches for radar cross-section (RCS) simulation, allowing, that is, the computation of the scattering of real objects from 3D models. However, it is limited by computer memory and computation time. In this paper, the authors explore the question of the balance between the possible acceptable level of 3D model simplification and the time benefit associated with a decrease in computational overhead due to the reduction of the model geometry complexity. A spatial volume-based RCS characterisation quality index is proposed to help determine the level of simplification to achieve a significant reduction in computation time while maintaining an acceptable level of similarity. The authors present the results of the calculations performed for perfectly conducted sphere 3D models with varying levels of geometry simplification for which a simple analytical solution exists. Furthermore, the results of the computations performed for a generic missile model set are shown. Possible areas of the application of the proposed approach are also considered.