IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, cilt.71, sa.2, ss.2011-2015, 2023 (SCI-Expanded)
Remainders of various forms of series expressions of a function F(x), which arises frequently in the high-frequency solutions of electromagnetic wave radiation and scattering problems, are transformed into some integrals. Then, the saddle-point method is applied to those integrals to obtain accurate approximations for terminating the series expressions. The accuracy improvements are illustrated by numerical examples and graphs.