Trans-ionospheric propagation experiment at HF-band: Channel measurement and modelling

The HFPE technological experiment aims at consolidating a new concept of long range transmissions between ground and the Low Earth Orbit. This concept relies on over-the-horizon transionospheric links in the HF-band. To prepare this experiment, propagation modelling and measurements have been carried out. In particular, a HF link planning software, MSATIS, has been tested with respect to experimental data, and improved. One of the major improvements is a global prediction of the ionospheric foF2 and hmF2 characteristics based on IONEX data. For air interface optimization, multipath effects not addressed by MSATIS had also to be characterized. Ray launching has been used to identify typical short-term propagation channels representative of HFPE propagation conditions.