Patent ID: 6418082
Filing Date: 2002-07-09
Classification: G01S,G01V

Abstract:
An apparatus comprising:a mooring platform for anchoring the apparatus to a bottom ground surface covered by a body of water; a buoyant chamber; a directional frequency analysis and ranging (DIFAR) sensor positioned within the buoyant chamber, the DIFAR sensor including: an x hydrophone pair for sensing sounds along an x axis; a y hydrophone pair positioned orthogonally to the x hydrophone pair for sensing sounds along a y axis; and a tether having a first end and a second end, wherein the first end of the tether is coupled to the mooring platform and the second end of the tether is coupled to the buoyant chamber to suspend the buoyant chamber a pre-defined distance from the bottom ground surface, and to orient the x hydrophone pair and the y hydrophone pair so that the x axis and the y axis form a plane substantially co-planer to a top surface of the body of water.