Analyzing Ultra-Wideband Electromagnetic Problems by Time Domain Electric Field Integral Equations

This letter demonstrates the capability of time domain integral equation (TDIE) in addressing ultra-wideband electromagnetic responses by a single simulation. Comparing with the frequency-domain moment method (MoM) solvers, the TDIE does not require any essential change of the algorithm structures for analyzing electromagnetic problems from zero to microwave frequencies. To obtain the correct results by TDIE at very low frequencies, we propose a Static Error Current Subtraction Method (SECS) for the capacitance and inductance problems even at ultra-low frequency (10-25 Hz). The smallest electrical size of the numerical examples is less than 10-35 wavelengths. Moreover, the proposed SECS method is applicable to both marching-on-in time (MOT) and marching-on-in degree (MOD) schemes. Several numerical examples are given to validate the accuracy and universality of the proposed algorithm.