Electromagnetic coupling and interference predictions using the frequency-domain physical optics method and the time-domain finite-element method

Two predictive techniques, the frequency-domain physical optics (PO) method, and the time-domain finite-element (FETD) method, are presented with application to system-level electromagnetic coupling and interference issues. Full-wave solvers, such as finite-element and integral-equation methods, are very powerful but have practical upper frequency limits of application. The physical optics method, which has traditionally been used for far-field scattering and antenna pattern predictions, is shown in this paper to be useful for estimating on-platform antenna coupling. Although PO methods do not provide the fidelity and accuracy of full-wave methods, they can nevertheless often provide useful coupling estimates for the entire platform in a matter of seconds, whereas full-wave methods may take many hours (or days) of computation time and often solve only a subset of the overall platform. The utility of PO methods is demonstrated in this paper through validation of antenna coupling on a Boeing F15B.