A.Serrated range rings B.Indirect echoes C.Multiple echoes D.Blind sector
A.Set and drift of the current B.Relative track information C.Predicted time of CPA D.Initial range of acquisition
A.enhance weak target echoes and brighten them on the PPI B.reduce clutter over the entire PPI by shortening the echoes C.only suppress weak targets to a limited distance from the ship (sea clutter) D.reduce the beam width to provide a map-like presentation for navigation