PIECEWISE SURFACE IMPEDANCE BOUNDARY CONDITIONS BY COMBINING RYTOV'S PERTURBATION METHOD AND LEVEL SET TECHNIQUE

In this paper, we propose a computational method for constructing variable surface impedance, based on combining Rytov's perturbation method and level set technique. It is well-known that the choice of the most appropriate order of Rytov's expansion is important both for accuracy and implementation. By using level set method, we constructed a piecewise distribution of low- and high-order surface impedance boundary conditions on the surface of an arbitrarily shaped conductor. It is found that the proposed method is able to give good results both in terms of accuracy and implementation cost.