Archives of Acoustics, 46, 1, pp. 177–181, 2021
10.24425/aoa.2021.136571

Influence of Overpressure Breathing on Vowel Formant Frequencies

Milan VOJNOVIĆ
Life Activities Advancement Center
Serbia

Miomir MIJIĆ
University of Belgrade
Serbia

Dragana ŠUMARAC PAVLOVIĆ
University of Belgrade
Serbia

Nebojša VOJNOVIĆ
University of Belgrade
Serbia

Voice controlled management systems are based on speech recognition techniques. The use of such systems in combat aircraft is complex due to a number of critical factors which affect the accuracy of speech recognition, such as high level of ambient noise and vibration, use of oxygen masks, serious psycho-physical stress of speakers, etc. One of the specificity of the oxygen mask application is overpressure breathing. The results of the simulations presented in this paper show that the presence of overpressure on the order of 1000 Pa in the vocal tract has a significant influence on the first two formant frequencies. The formants discrimination field is significantly reduced when oxygen mask is used, influencing both perceptive and automatic discrimination of spoken vowels.
Keywords: mask; overpressure; transfer characteristic; vocal tract.
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Copyright © The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0).

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DOI: 10.24425/aoa.2021.136571