An Efficient Wide-Angle/Wideband RCS Prediction Method for PEC Targets With Indeterminate Shape

A multidomain prediction method (MDPM) is introduced for computing radar cross section (RCS) across the frequency, angular, and spatial (geometric shape) domains. Then, the electromagnetic scattering characteristics for targets of indeterminate geometries are obtained rapidly in scalar domains. Compared with the traditional 1-D estimation methods, the proposed method in this article can achieve effective prediction in both scalar and vector domains. Specifically, the vector domain is derived from the point clouds of the model. The surface current can be approximated using a uniformly convergent bivariate Chebyshev polynomial. In previous studies, the Chebyshev polynomial has often been replaced by the Maehly approximation (a rational polynomial) to extend the prediction range. However, due to the singularity of the coefficient matrix and the lack of certain coefficients, this substitution does not always result in increased accuracy. Consequently, the classical Chebyshev polynomial approach is adopted to enhance the stability and accuracy of the results. Additionally, the coefficient matrix is calculated using circular indexing, thereby optimizing the algorithmic framework further. The derivative calculations are not involved in the proposed method. It not only simplifies the solution process and reduces memory consumption but also calculates the scattering characteristics of complex targets. Compared to the Monte Carlo (MC) method, the proposed method can significantly enhance efficiency while ensuring accuracy.