Accelerated Evaluation of Quasi-Static Interaction Integrals via Cubic Spline Interpolation in the Framework of the PEEC Method

Fast Fourier transform (FFT)-based techniques are used in conjunction with iterative solvers to accelerate matrix-vector products in the framework of integral-equation-based methods. Even using this type of technique, the interaction matrix fill-in can be time consuming because of the huge number of coefficients to be computed. In this work, a cubic spline interpolation in space of the coefficients of potential is proposed in the framework of the partial element equivalent circuit method. The presented method can be used in the framework of FFT-based volume integral techniques, such as the partial element equivalent circuit technique. Two numerical tests are presented confirming a significant speedup while preserving the accuracy.