Analysis of array structures using Tangential equivalence principle algorithm with MLFMA

The equivalence principle algorithm (EPA) is a kind of domain decomposition scheme for the electromagnetic scattering and radiation problems based on integral equation (IE). This method is suited for solving multi-scale problems and array structures with same elements. However, the original EPA can lead to a loss of accuracy in some cases. Compared with the EPA, Tangential EPA (T-EPA) has the better accuracy. But the filling time for the impedance matrix in T-EPA is still time consuming. In this paper, MLFMA is proposed to speed up the matrix-vector multiplication. Numerical results are shown to demonstrate the accuracy and efficiency of the present technique.