STEMO, a stabilized toolkit for embedded dielectric structures with moment methods

The low frequency instability in the method of moments becomes important when objects smaller than the wavelength have to be computed. For a PEC (Perfectly Electrically Conducting) body, this leads to uncoupling or splitting the integral equations by using first the MFIE (Magnetic Field Integral Equation) for the currents and consecutively the EFIE (Electric Field Integral Equation) for the charges. For dielectric bodies, the charge is reintroduced. The contribution of this paper consists in implementing an efficient technique, reducing the computational complexity, in time but mostly in memory. A toolkit has been developed to perform accurate computations. The technique has been verified quantitatively, checking the charge and current distributions against analytic solutions where existing, as well as qualitatively against the boundary conditions for the scattered field. Many examples will be given, both in frequency and in time domain (obtained by inverting frequency domain calculations including the DC (Direct Current) component).