Wave guides for electrical transmission

The transmission of electric power at extremely high frequencies through rods or “wires” of dielectric and through metal tubes, without the usual return conductor, was predicted mathematically many years ago. Recently experiments have confirmed this theory. Wave guides offer the possibility of transmitting very wide frequency bands and consequently extremely large numbers of speech channels without the high attenuations encountered in radio; in fact, constantly decreasing attenuation with increasing frequency is predicted for one type of wave. Some of the properties of the waves and the apparatus used in studying them are described in this article.