Time domain scattering from arbitrary 2D scatterers obtained from frequency domain data generated numerically

A coupled finite element/boundary element numerical method for solving 2-D scattering problems has been developed. The CEM (coupled element method) produces results from which the scattered fields from an arbitrary shaped, inhomogeneous object can be calculated for a specified frequency. The accuracy of the method has been verified over a wide frequency range, and estimates of the number of finite elements for an acceptably accurate solution, at specific frequencies, are given. A number of frequency data points can be used together with an inverse Fourier transform to obtain a simulated time-domain pulse response. The time-domain resolution and alias-free region are dependent on the frequency band and number of data points. This response enables one to investigate more carefully the scattering contribution of the different regions of a scattering object. >