HF radio emissions as a tool of ionospheric plasma diagnostics

The electromagnetic emission in the topside ionosphere has been investigated since the first satellites were located on the orbits. HF measurements can be used to diagnose the different electron plasma waves as well as the typical ionospheric parameters like f0F2. This paper presents the examples of measurements of the ionospheric RF radio noises in 0.1-10.0 MHz frequency range, which have been observed on the boards of the Intercosmos-19, Intercosmos-24, APEX satellites in the period 1979-1992, and the current experiment CORONAS