Sea clutter rejection using virtual radar receiver arrays

Sea clutter suppression in radar is a challenging problem since the Doppler frequencies of certain targets on the sea surface cannot typically be distinguished from the broadband sea clutter using narrowband array processing. In this study, separation of sea clutter by a virtual sensor array derived from single passive sensor using generalised sidelobe canceller (GSC) is investigated. Clutter returns in one range gate tend to be correlated with those in neighbouring gates, while exhibiting disparities from the responses associated with targets. As a result, suitable subspaces can be formed from returned radar mixtures, which enables suppression of the unwanted clutter components. Results obtained using experimental data highlight that the proposed approaches can boost signal-to-interference-plus-noise ratio (SINR) by improving target-signal strength and mitigating broadband clutter.