Investigation on Low-frequency Breakdown of Electric Field Integral Equation Using 16-byte Floating-point Number

The phenomenon of low-frequency breakdown in the electric field integral equation (EFIE) occurs when the wavelength of the electromagnetic wave is much larger than the size of the targets or the discretized elements, because the contribution of the vector potential are swallowed by the contribution of the scalar potential due to the finite precision of the floating-point numbers adopted. The increase in floating-point precision has rarely been reported as a scheme to mitigate the low-frequency breakdown problem. In this report, we use the Mie analytical solutions as well as AEIFE as reference results and compute it with the increased precision of EFIE to compare the critical breakdown frequency at which the perfectly electric conducting sphere reaches for floating-point number precision at 4-byte, 8-byte, and 16-byte, respectively. Furthermore, we compare the accuracy of the calculation results and the resource consumption during the calculation with the popular augmented electric field integral equation (AEFIE) method when analyzing multi-scale targets.