Electromagnetic coupling and radiation analysis of lossy multiconductor lines in high speed switching circuits

The effect of line losses on crosstalk and radiation in a multiconductor microstrip transmission line system, has been investigated using the modal theory in the frequency domain. The fast Fourier transform (FFT) has been employed to determine the time domain response of the lines to signals from high speed switching circuits. The crosstalk reducing effect of a lossy shield line has also been studied using this technique. The frequency domain expression for the line currents has been used along with the asymptotic form of dyadic Green´s function for a grounded dielectric slab, to determine the frequency spectrum and the waveform of the radiated field