Steady-State Analysis of Long Transmission Lines by Normal Modes, Part I: General Theory

Unbalanced periodic voltages and currents applied to transmission lines can be resolved into sets of voltages and currents, each of which is characterized by its own propagation constant and each of which is independent of the others. Each set can then be operated upon separately and recombined at other points of the system. These sets are called normal modes and are unique in possessing these characteristics. The method of resolution is applied both to infinitely long lines and short lines. These modes differ from the generally accepted natural modes.