TY - JOUR A1 - Mosig, Juan Ramón AU - Álvarez Melcón , Alejandro T1 - Green’s functions in lossy layered media: integration along the imaginary axis and asymptotic behavior Y1 - 2003 SN - 0018-926X UR - http://hdl.handle.net/10317/642 AB - This paper presents an efficient technique for evaluating Green’s functions associated to layered media, when formulated as Sommerfeld integrals in the space domain. The key step in the formulation is that Sommerfeld integrals are computed choosing a suitable integration path which is closed through the imaginary axis of the complex spectral plane. It is shown that with this original choice of the integration contour, the numerical effort usually involved in the evaluation of Sommerfeld integrals can be greatly reduced, specially when large source-observer distances are involved. One asset of this technique is that it can be easily incorporated into integral equation based CAD packages for the efficient analysis of complex printed microwave circuit and antennas. In addition, the theoretical developments needed to set up the numerical algorithm throw a new light on the asymptotic behavior of the layered media Green’s functions for large source-observer distances. KW - Teoría de la Señal y las Comunicaciones KW - Comportamiento asintótico KW - Ecuaciones integrales KW - Funciones Green KW - Circuitos impresos KW - Antenas KW - Asymptotic behavior KW - Integral equation (IE) KW - Circuit board KW - Antennas KW - Green's functions LA - eng PB - IEEE Antennas and Propagation Society ER -