Analyzing Ultrawideband Electromagnetic Problems by Time-Domain Electric Field Integral Equations

This letter demonstrates the capability of the time-domain integral equation (TDIE) in addressing ultrawideband electromagnetic responses by a single simulation. Comparing with the frequency-domain method of moments (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 frequencies (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 and marching-on-in degree schemes. Several numerical examples are given to validate the accuracy and universality of the proposed algorithm.