Solutions of wide-band RCS of objects using general characteristic basis functions

A fast and efficient numerical approach is proposed to analyze the wide-band electromagnetic scattering characteristics based on the characteristic basis function method (CBFM). The general characteristic basis functions (GCBFs) are derived from the primary characteristic basis functions (PCBFs) and the secondary level characteristic basis functions (SCBFs) by applying a singular value decomposition (SVD) procedure at the highest frequency point. These GCBFs can be reused for each frequency, so the electromagnetic scattering problem on the desired frequency band can be solved fast. Finally the adaptive cross approximation (ACA) algorithm is applied to accelerate the impedance matrix element computation as well as matrix vector multiplication in the construction process of the SCBFs and the reduced matrix. The accuracy and efficiency are improved significantly compared with the traditional method. Numerical results demonstrate that the proposed method is accurate and efficient.