Phase Changes Induced in a Diagnostic Radio Wave Passing Through a Heated Region of the Auroral Ionosphere

Some results of recent high-latitude ionospheric heating experiments are presented. Phase changes were induced in a diagnostic radio wave reflected from the lower F region of the ionosphere as it passed through a region of the ionosphere which was being illuminated by a high-power electromagnetic wave. From the results obtained there are indications that anomalous absorption contributes much more than deviative absorption to ionospheric heating at high latitudes.