Performance Characteristics of a Parabolic and a Conical Underwater Acoustic Reflector.

The beam patterns of a parabolic and a conical underwater acoustic reflector of comparable size, using the same source transducer, showed the paraboloid to exhibit superior performance. Relatively soft foam-rubber backing appears suitable for depths to at least 90 ft. Use of secondary reflectors, i.e., front disk baffles to reduce side lobes, was found to have little or no beneficial effect on either the cone or the paraboloid performance. Results of experimentation with the paraboloid indicated an optimum point at which acoustic performance and physical size became a tradeoff. Author