Ray‐Tracing Study of HF Ducting Propagation With Satellites

Open Access
Publisher Website
Google Scholar
Abstract
Ray patterns‐showing the spatial distribution of rays emitted from a transmitter and then progressively refracted in the medium‐ are presented for frequencies from 13.6 to 40 Mc/s, and for variations of the ionosphere in one to three dimensions. The patterns portray the elevated radio ducts, with down‐to‐earth contacts, responsible for long‐distance and round‐the‐world propagation. It is shown that constancy of Doppler frequency shift, in signal reception from an antipodal satellite pass, is a condition enabling the signal to persist some minutes, and that this constancy implies propagation off the great‐circle path .