A robust and accurate method for the computation of mixed potential Green's function in cylindrically stratified media

Accurate computation of the spatial-domain mixed potential Green’s function (MPGF) in cylindrically stratified media is achieved by a judicious cooperation of two recent works on the same topic. An improved procedure is devised to provide accurate values of the MPGF both in the near and far field, including the axial line region. A numerical approach based on the generalized pencil-of-function method is applied to eliminate the axial line problem, and the rational function fitting method is employed to improve accuracy and stability in the far field. As a result, a robust and efficient method is developed, and good accuracy is achieved both in the near and far field, and along the axial line.