Target Extraction and Imaging of Maritime Targets in the Sea Clutter Spectrum Using Sparse Separation

Detection and imaging of endoclutter maritime targets is a difficult problem, because the signal return of the target and the clutter overlap in both Doppler frequency and time. Consequently, traditional Doppler filtering is severely limited in terms of extracting the target signature for further processing. This letter proposes a new sparsity-based Doppler filtering and extraction paradigm for maritime radar where the different backscattered signals are separated in the endoclutter region based on their Doppler bandwidths rather than their Doppler frequencies. The novelty of this letter is successful extraction of the target profiles in the endoclutter region using the application of morphological component analysis with time-frequency transforms. Illustrative results of the proposed approach for boat Doppler profile extraction and inverse synthetic aperture image formation outperform traditional range-Doppler processing in endoclutter. The method represents a new paradigm for target detection and imaging in sea clutter.