Polarization of High-Frequency Waves and Their Direction Finding

This paper describes the results of experiments which were conducted during the past two years for the purpose of studying the high-frequency transmission phenomena, and some physical explanations deduced therefrom. The authors are of opinion that it is preferable to take up the questions of polarization and direction finding simultaneously. For the measurements of polarization, the authors. used a single doublet which may be rotated in the directions of three coordinates, and measured the component electric forces by it. For direction measurements, they used an Adcock-type aerial which was specially designed by themselves so as to be suitablefor the observations on high-frequency waves. The conclusions thus obtained are briefly summarized as follows: (1) The waves are, as a whole, elliptically polarized, and in general the state of polarization largely depends on the transmission distance. When the distance is short, the state of polarization will usually be horizontal, whereas it is generally vertical when the distance is long. In either case, the direction measurement is satisfactory. (2) Within a certain distance, the direction measurement is impossible owing to the scattering of the waves. (3) If transmitter and receiver are so situated as to be in nearly antipodal relation, the main waves do not always propagate along the great circle path, but take various routes according to the distribution of day and night.