Broadband hf emissions as an indicator of global changes within the ionosphere Original Research Article

The electromagnetic emission in the topside ionosphere has been investigated since first satellites were located on the orbits. The BF measurements can be used to diagnose the different electron plasma waves as well as the ionospheric electron density distribution. The paper presents the global distribution of HF radio noises in 0.1–15 MHz frequency, detected on board of low orbiting satellite CORONAS-1. The well-manifested global distribution feature of the observed spectra appears as remarkable enhancement of spectral density over Europe and part of Asia. The aim of this paper is to discuss the morphological and physical property of broad band HF emissions and correlation these events with human activity as well as natural environmental influences.