The Spectral Integral Method (SIM) for the Scattering from an Arbitrary Number of Circular PEC Cylinders

We present an accurate spectral integral method (SIM) for the analyses of scattering from multiple circular perfect electric conductor (PEC) cylinders. It solves the coupled surface integral equations by using the Fourier series and addition theorem to decouple the system. The SIM has exponential convergence so that the error decreases exponentially with the sample density on the surfaces, and requires only about 2–3 points per wavelength (PPW) to reach engineering accuracy defined as higher than 99% accuracy (or with an error smaller than 1%). Numerical results demonstrate that the SIM is much more accurate and efficient than the method of moments (MoM), and thus can be potentially used as the exact radiation boundary condition in the finite element and spectral element methods.