Iterative solutions of MFIE for computing electromagnetic scattering of large open-ended cavities

The analysis of high-frequency scattering from electrically large open cavities is addressed. A magnetic-field integral equation (MFIE) for the equivalent currents on the interior cavity walls is obtained and solved by two different algorithms based on the high-frequency principles of physical optics (PO). Once the currents are known, the scattered fields are obtained by using aperture integration (AI) in the cavity mouth, or a reciprocity integral (RI) over a surface close to the termination. Numerical results are presented which demonstrate the convergence and accuracy of the proposed methods, by comparison with a modal reference solution