Accession Number : ADD011194

Title :   Frequency Independent Acoustic Antenna.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Sternberg,R L

Report Date : 24 Apr 1984

Pagination or Media Count : 7

Abstract : A frequency independent log periodic acoustic device is utilized for the transmission or reception of underwater sound. The acoustic device when used in conjunction with any substantially plane wave receiving or transmitting transducer produces a directional, substantially constant beamwidth diffraction pattern for radiation or reception of underwater sound signals. A key element of the device is a particularly shaped plate or diaphragm, called a filter plate, made of stainless steel or other material having suitable acoustic properties. The filter plate on being placed in front of any plane wave receiving or transmitting transducer acts automatically to make the beamwidth of the diffraction pattern of the combined device constant, regardless of frequency.

Descriptors :   *Patents, *Acoustic equipment, *Electroacoustic transducers, *Underwater sound equipment, *Acoustic filters, Diaphragms(Mechanics), Underwater sound signals, Diffraction, Plane waves, Broadband, Reception, Acoustic properties, Patterns, Transducers, Constants

Subject Categories : Electrical and Electronic Equipment
      Acoustic Detection and Detectors
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE