108–216 Mc./s. Radio Signals from Satellites below the Horizon

Abstract

SMYTH RESEARCH ASSOCIATES have been conducting an experimental programme on low-angle refraction of radio waves penetrating the atmosphere. Satellite transmitters at 108, 162, and 216 Mc./s, have been used as signal sources in these studies. During the course of the measurements (June, July and August 1960) it was found that, on the majority of passes, signals were received while the satellite was well beyond the radio horizon. Out of a total of 49 cases when such ‘precursor’ signals were sought, only 14 failed to yield signals for at least one minute beyond the radio horizon.