A hybrid method of moments-marching on in time method for the solution of electromagnetic scattering problems

The time step size required by existing time-domain integral equation solvers for the solution of electromagnetic scattering problems is inversely proportional to the highest frequency present in the incident signal. This makes existing solvers inefficient, especially when the incident wave is narrowband in nature. This work presents a new time marching approach in which the time step size is inversely proportional to the bandwidth of the incident signal. The method is based on analytic signal theory and Hilbert transforms, which are used to transform the standard integral equations of electromagnetics into equations for the complex envelope of the current. Numerical results show the method to be both stable and accurate.