Analysis of time-varying HF propagation characteristics

It is well-known that the ionosphere is very disturbed at high latitudes, which causes difficulties in establishing and maintaining high-frequency (HF) communications links. In addition to seasonal and diurnal variations, short term changes in channel parameters such as Doppler spread, multipath spread and signal-to-noise ratio are observed. In this paper, we present an analysis of data from a high-latitude HF measurement campaign which concentrates on the variability of the channel characteristics over shorter time periods