Accession Number : AD0753650

Title :   Jungle Acoustics III: Effects of an Acoustic Filter on the Detection of Voices through the Jungle Canopy.

Descriptive Note : Final rept.,

Corporate Author : ARMY TROPIC TEST CENTER APO NEW YORK 09827

Personal Author(s) : Dobbins,Delaney A. ; Dubuisson,Adrian U.

Report Date : JUL 1972

Pagination or Media Count : 30

Abstract : The United States Army Tropic Test Center conducted a study of auditory detectability of human voices from the jungle floor through the canopy in the Panama Canal Zone during October and November 1970 (wet season) and April 1971 (dry season). A total of 240 transmissions were made from a speaker system to acoustic sensors at heights ranging from 5 to 100 feet. Voice transmissions were conducted at slant range distances from 600 to 1200 feet from sensors. The recorded transmissions were later played back to a total of 60 soldiers from TOE units under two conditions-filtered and unfiltered. The soldier listeners attempted to distinguish human vocies from natural jungle ambient noises. The study demonstrated that filtering and vertical sensor position have a significant impact on the detection capabilities of an acoustic sensor system tested or operationally deployed in jungle areas. (Author)

Descriptors :   (*ACOUSTIC DETECTORS, TROPICAL REGIONS), (*JUNGLES, SOUND TRANSMISSION), AERIAL RECONNAISSANCE, SPEECH, AUDITORY PERCEPTION, BACKGROUND, METEOROLOGICAL PHENOMENA, FEASIBILITY STUDIES

Subject Categories : Acoustic Detection and Detectors
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE