Oblique Sounding of the Ionosphere by Means of an Ionosonde–Direction Finder with Chirp Signal

Abstract

We give a mathematical rationale, an algorithm, and hardware implementation for a multichannel ionosonde–direction finder with chirp signal. The results of experimental studies of twodimensional angle–frequency characteristics on the Cyprus—Rostov-on-Don meridional obliquesounding path are presented. It is shown that both regular (terminator-related) and irregular (caused by the passage of a traveling ionospheric disturbance through the propagation path) transverse (with respect to the propagation path) horizontal gradients of the electron number density lead to a deviation of the azimuth of the high-angle ray in the direction of the N_e gradient. The experimental data are compared with the simulation results.