44 OTH Radar Transient Noise Excision Based on S Transform and Ridge Detection

Skywave over-the-horizon radar (OTHR) often encounters strong transient noise which raises the power spectrum of the return signal and dramatically degrades the target detection performance of the radar system. To locate and eliminate the transient noise without distorting the clutter return (so that the clutter can be properly handled in a subsequent processing), one can transform the received signal into the time-frequency plane using an appropriate time-frequency representation. In this paper, we propose a transient noise excision algorithm based on the S transform and ridge detection. The proposed algorithm has low computational complexity and is more suitable for the skywave OTHR than the existing time- frequency transient noise excision algorithms. Using real experimental skywave OTHR data, simulation results are provided to verify the effectiveness of the new algorithm.