DEVELOPMENT OF THE ULTRA-HIGH-FREQUENCY RADIO RANGE PART ⅠTHE ULTRA-HIGH-FREQUENCY AURAL RADIO RANGE

摘要

This report describes a series of aural radio range experiments conducted at Indianapolis, Ind., Pittsburgh, Pa., and Washington, D. C, at frequencies of 63 and 125 megacycles. The results of numerous ground and flight tests using vertical and horizontal antennas are discussed with particular reference to the radio frequency, multiple courses, cone-of-silence characteristics, polarization effects, reflection effects, noise, atmospherics, distance range, ionosphere reflections, and aircraft antennas. The report shows the progression of development from vertical polarization to horizontal polarization using crossed dipoles to the finally adopted horizontally polarized array using horizontal loops which have substantially pure polarization. The field pattern of the adopted array possesses two very desirable characteristics, namely, a considerable increase of field strength on-course and a reduction of field strength off-course. These characteristics are not available with the conventional crossed figure-of-eight radio range pattern.