Characterization of Ionosphere Waveguide Propagation by Monitoring HAARP HF Transmissions in Antarctica.

摘要

The Project was aimed at experimentally investigating the possibility of exciting the ionospheric interlayer duct channel using powerful radiation from the heaters HAARP (Alaska, USA) and EISCAT (Troms , Norway), as well as from HF broadcasting stations RWM (Moscow, Russia) and CHU (Ottawa, Canada). Major attention was paid to analyzing the possibility of exciting the interlayer ionospheric waveguide which support super-long range HF propagation with a small amount of attenuation. To monitor the radiation, a compact-size receiving complex was developed which is capable of measuring the signal intensity and spectral characteristics in an off-line automatic mode. Two facilities have been constructed in the course of the Project. One was deployed in Ukraine at the Low-frequency Observatory of the IRA NASU (Martova village, Kharkov region) in 2012, while another was installed at the Ukrainian Antarctic station Akademik Vernadsky in the Antarctic in 2013. In all, about 100 hours were spent observing the radiation from the heaters (primarily EISCAT) and more than 3000 hours monitoring signals from broadcast radios. In a number of cases the signal strengthening was detected for the super-long range radio links (Alaska-Antarctica and Northern Scandinavia-Antarctica) which effect can be regarded as a result of the waveguide propagation. A pioneering feature of the developed theoretical model is accounting for the regular ionospheric refraction. The aspect-sensitive contours in the ionosphere and on the Earth s surface have been calculated for all the transmitting and receiving sites for the current ionospheric conditions. A software package was developed for the remote control of the receiving complexes and visual representation of the measurement results in real-time over the internet. The most productive experiments were performed during the BRIOCHE heating campaign in June 2014. The detailed description of this campaign is included in Chapter 4 of the Final Report.