Accession Number : ADA299063

Title :   Employing Digital Signal Processing for Acoustical Analysis,

Corporate Author : NAVAL ACADEMY ANNAPOLIS MD

Personal Author(s) : McElmurray, Brian G.

PDF Url : ADA299063

Report Date : 09 MAY 1995

Pagination or Media Count : 62

Abstract : In the field of communications, digital signal processing based systems offer distinct advantages over comparable analog systems. Because analog systems have a tendency to change over time, they are inflexible and require constant attention. Digital based systems are stable and allow a great deal of flexibility. These advantages, as well as the advances in processor speed, enable digital based systems to surpass the accuracy, precision, and reliability of their analog counterpart. In underwater detection applications, digital signal processing techniques advance the level of sophistication in sensors and analysis, aiding in the detection of narrow band noises created by man-made sources like a submarine's machinery and propeller. With today's technology, it is possible to design receiving systems that capitalize on the digital advantages. In this project, digital signal processing was employed for the acoustic analysis of a sonobuoy's transmitted signal. The aim of the project was to construct a receiving system based solely on digital signal processing (DSP) that performed real time extraction operations on the components of a common, fleet sonobuoy's received signal. These components contained the necessary information to resolve a contact's direction and sound signature. The system was provided a signal from a sonobuoy's receiver that simultaneously contained five signal components. The system extracted sound from the signal's left, right, and omnidirectional sources. The processed sonar information was displayed on an oscilloscope and spectrum analyzer as well as audible through a speaker system.

Descriptors :   *SIGNAL PROCESSING, *SONAR SOUND ANALYZERS, *DIGITAL FILTERS, REAL TIME, ACCURACY, RELIABILITY, EXTRACTION, SPEECH, ACOUSTIC SIGNATURES, DIGITAL COMMUNICATIONS, UNDERWATER ACOUSTICS, SUBMARINES, SONAR, FIELD EQUIPMENT, SONOBUOYS, NARROWBAND, NOISE(SOUND), SOUND ANALYZERS, OMNIDIRECTIONAL, PROPELLER NOISE.

Subject Categories : Acoustic Detection and Detectors
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE