A Spectral Integral Method for Smooth Multilayered Bodies of Revolution

A spectral integral method (SIM) is developed to solve the scattering problem from smooth multilayered bodies of revolution (BoRs). This SIM is a spectral method to improve the accuracy and efficiency of the SIM by the fast Fourier transform (FFT) algorithm. This method can achieve high accuracy and greatly reduce the computational time consumption. In our BoR-SIM, the BoR generatrix current is expanded by the truncated Fourier series. Then, the impedance matrix is generated in the spectral domain to solve the scattering problem. Unlike the conventional methods that need eight to ten segments per wavelength, in the BoR-SIM, two points per wavelength are adequate to achieve high accuracy according to the Nyquist theorem. Being accelerated by FFT, this method shows a significant efficiency advantage over the conventional BoR method. Numerical results demonstrate the accuracy and efficiency of our new method. By combining with the Poggio-Miller- Chang-Harrington-Wu-Tsai surface integral equations, this method can be used to solve many practical scattering problems.