An Efficient Pole Extraction Technique for the Computation of Green's Functions in Stratified Media Using a Sine Transformation

An efficient and automatic algorithm for the extraction of surface wave poles of the multilayered spectral-domain Green's function is presented. With the sine transformation, we have managed to locate any pole, no matter how close to the branch point singularity lies, something that has not been feasible with techniques proposed till now. The aforementioned transformation maps the k_rho-plane to the w-plane, where the branch point is removed, thus enabling the application of a fast numerical contour integration technique proposed, which is inaccurate when dealing with poles very close to the branch point