Superresolution for high-frequency radar

High-frequency (HF) radars require large-array antennas to achieve narrow beamwidths and are required to discriminate targets with low Doppler shifts compared with microwave radar. Superresolution processing can discriminate signals at separations much less than the beamwidth or conventional Doppler bin width (or conversely, achieve a given minimum resolvable separation with a smaller array or less time-on-target). Simulation results and analysis of real radar data presented here show at least a 2-fold improvement compared with conventional processing, assuming simple theoretical gain manifolds. A novel polarisation-sensitive superresolution algorithm applicable to skywave HF radar is also discussed.