| dc.description.abstract | High-frequency (HF) radio wave propagation at high latitudes is greatly affected by geomagnetic and ionospheric
conditions, and both civilian and military users need reliable forecasts of the propagation environment. In particular, the
presence of large electron density gradients within the polar cap and auroral oval often lead to off-great circle
propagation, which can be a serious problem for transmitter locating techniques based on direction finding and
triangulation. Based on the large amount of data expected from a new Direction Finding (DF) experiment in North
Scandinavia, a statistical classification of signal directional characteristics under various geophysical conditions and for
all seasons can be made. In this report, cases of both quiet and disturbed geomagnetic conditions have been studied, and
comparisons have been made with data from magnetic disturbance observatories in the same geographic region. In
addition a first statistical study of one month of DF data is presented. | en_GB |