Modelling the ionospheric effects in HF radar long term integration

High Frequency radars usually use reflected waves from ionosphere to perform continuous surveillance of very large and far off areas. In the case of long term integration, the ionosphere instability affects the radar image and thus induces poor detection and high probability of false alarm. This problem appears in surveillance issues dealing with slow targets such as vessels. Such an issue also occurs in surface wave radar due to the lack of directivity of the transmitting antennas. In this paper, we propose probabilistic models of the ionosphere effects assuming that only the phase path fluctuation has a meaning in the radar point of view. Different models have been built and compared to a real case. It appears that the deviation in range and Doppler are meaningful. These models will be integrated in the radar processing in order to synthetize highly realistic radar data and estimate the radar parameters in case of turbulent ionosphere (i.e. range-Doppler shifts and uncertainties as well as detection and false alarm probabilities). The obtained results will be presented during the EuCAP 2016 conference.