Efficient numerical modeling of large-scale microstrip structures

For full-wave numerical modeling of microstrip structures, the most popular approach involves an integral equation formulation and the application of the method of moments (MoM). This technique often becomes computationally intractable when large structures are involved. In this case, the technique leads to store a large and dense matrix. In this paper, the precorrected-FFT method is employed to eliminate the need to store the impedance matrix and accelerate the matrix-vector product. This paper extends the method to the analysis of microstrip structures. In the approach, the mixed potential integral equation (MPIE) is developed in the spatial domain and discretized using triangular elements with RWG basis functions. Then the discrete complex-image method (DCIM) is used to compute the Green´s functions efficiently and the precorrected-FFT method is used to accelerate the matrix-vector product. The resulting algorithm reduces the memory requirement and computational cost to O(N) and O(NlogN) respectively. Numerical examples are presented to demonstrate the efficiency and accuracy of the method.