Simulation models of a dissipative transmission line above a lossy ground for a wide-frequency range. II. Multiconductor configuration

For pt. I see ibid., vol.38, no.2, p.127, 1996. The simulation model of a multiconductor dissipative line above a lossy ground, based on the exact formulation of the Maxwell equations, is proposed for a wide frequency range. The procedure is an extension of the analysis of single conductor configurations. The exact expression of the matrix modal equation of the line is first proposed, assuming that in the system there are as many dominant discrete modes of propagation as there are conductors. New expressions of the distributed series-impedance and shunt-admittance matrices are proposed, with reference to the definition of the wire-to-ground voltage. Moreover, an easy-to-implement simulation model is proposed for use in computer codes, based on the logarithmic approximation of the Sommerfeld integrals and Bessel functions. Applications are carried out in order to compare the results of the proposed procedure and of the Carson (1926) theory, with reference to a three-conductor line above a lossy ground