On the Optimum Transmitting Wave Length for a Vertical Antenna over Perfect Earth

This paper considers the idealized problem of the transmission from a perfect vertical antenna over perfectly conducting plane earth. The distribution of current amplitude along the antenna is assumed to be sinusoidal. The antenna resistance is entirely radiational and has been calculated in a companion paper. The amount of energy radiated in various altitudinal directions is calculated, and distribution diagrams are given illustrating special cases. The conditions for the greatest economy of radiated energy are formulated for the case of a terrestrially located receiving station, the optimum wave length being determined as 0.39 of the fundamental. A transmitting arrangement of special interest for Heaviside-layer experiments is also described.