STC Using Coastal Map and Wavelet Transform for Sea Clutter Suppression

Detecting small or low-visibility targets in the presence of rough sea clutter is a critical challenge in coastal radar systems. Sea clutter refers to the unwanted echoes or reflections of radar signals caused by the dynamic sea surface majorly due to wind, waves, and other environmental factors. These echoes can mask the Radar returns from smaller targets like boats or aircraft, particularly at closer ranges. The complex and dynamic nature of this sea clutter poses a considerable challenge in the detection of targets of interest. The detection and tracking of targets of interest in marine situations are effectively improved by suppressing sea clutter. Sensitivity Time Control (STC) is a powerful method for mitigating near-range sea clutter, leveraging both spatial and temporal characteristics of the clutter returns. The STC curve estimate technique reduces the strength of signals from nearby range bins and marine clutter. STC curve estimation begins from the Radar transmit cover pulse on the received radar data. Attenuation is kept to the maximum during the on time transmit cover pulse. Rather than beginning curve estimation at the real coastal point (or range offset), the third order STC estimation using the raw input data for the mitigation of the sea clutter is approximated from the radar location for all the azimuth change pulse (ACP). Because of this, the calculated curve cannot adequately capture the abrupt transients at the land-water contact. Hence, a method is proposed for near range clutter mitigation using geographic map sources, like Global Self Consistent Hierarchical High Resolution Geographical (GSHHG) maps for finding coastal intersection points and Wavelet Transforms for finding erroneous sharp peaks.