High-Frequency Polyphase Transmission Line

The problems of the polyphase transmission line and the single-phase multiwire line have been formulated, based upon the vector-potential method. The transmission-line equations that determine the current and voltage relationships on these lines have been derived and solved. Formulas for the characteristic impedance of the lines have been thus obtained. They are useful in designing lines to feed polyphase radiating systems, and in computing the input impedance of triple-folded dipoles and other antennas.