Finite difference delay modeling with runge-kutta methods for the discretization of time domain integral equations

This paper proposes a convolution quadrature method based on implicit Runge-Kutta schemes for the temporal discretization, resulting in a higher-order convergence. Specifically, A-stable Radau IIA methods are employed for the mapping from the Laplace domain to Z-domain. The proposed method, with two and three stages, has thirdand fifth-order convergence respectively. The inverse Z-transform is computed with a numerical method using the discrete Fourier transform (DFT).