Fast Solutions of Dyadic Green's Function for Multilayered Isotropic Medium

The discrete complex image method, the window function method and the modified fast Hankel transform method are three popular fast techniques for calculating the dyadic Green's functions in a multilayered medium. In order to provide detailed knowledge of the accuracy, efficiency and application range of the three fast methods, the efficiency of the three methods are carefully examined. The results indicate that discrete complex image method is effective for general multilayered cases and modified fast Hankel transform method is also a powerful tool, while the accuracy and efficiency of window function method is strongly dependent on the multilayered geometry.