Efficient computation of mixed potential dyadic Green's functions for a 1D periodic array of line sources in layered media

In this paper an original approach is described for the efficient computation of the mixed-potential scalar and dyadic Green's functions for a one-dimensional (1D) periodic array of line sources embedded in a planar stratified structure. Suitable asymptotic extractions, corresponding to integrations in z of free-space Green's functions, are performed on the slowly-converging spectral series. The extracted terms are summed back through the Ewald method, modified and optimized to efficiently deal with these new free-space terms.