In this paper, the authors present a new approach based on scattering parameters matrix for the analysis of power line communication (PLC) signals in low voltage (LV) networks. The frequency spectrum associated with PLC signals extends from 1 MHz to 30 MHz. The low voltage network consists of multiconductor overhead lines and/or underground multiconductor cables. Dielectric and ohmic losses due to the presence of the ground are taken into account, and both differential- and common-mode propagations are studied. In the proposed formalism, the intrinsic properties of the transmission medium are fully described by the associated scattering parameters matrix. Hence, PLC signals along an entire LV network can be predicted by cascading the scattering parameters matrices associated with each line or cable. A computer code with a user-friendly graphical interface is developed which allows numerical simulation of PLC signals in LV networks. The simulation results are compared with measurements carried out on Swiss and French LV networks and a reasonable agreement is found