Calculation of Electrical Parameters of Two-Wire Lines in Multiconductor Cables

A rigorous method for the calculations of the characteristics of two-wire lines (twisted pairs) located in a metal shield is considered. In this paper, it is first shown that the mutual coupling between lines in multiconductor cables results in the appearance of electromagnetic interference (crosstalk) in communication channels; second, the asymmetry of excitation and loads results in the appearance of common-mode currents in the cable. The voltage values (interference) in the loads placed at the beginning and the end of the adjacent line are determined at a given power in the main line. The effect of loads connected between wires and shield is examined. The proposed method allows generalization of the obtained results in the case of multiconductor cables with losses.