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Atmospheric effects on voice command intelligibility from acoustic hail and warning devices
Jason H Bostron1, Timothy A Brungart, Andrew R Barnard
1Graduate Program in Acoustics and Applied Research Laboratory, The Pennsylvania State University, PO Box 30, State College, Pennsylvania 16804, USA. jason.bostron@gmail.com
The Journal of the Acoustical Society of America
|April 12, 2011
Summary
Weather conditions significantly impact voice command intelligibility at moderate signal-to-noise ratios (SNRs). Understanding atmospheric effects is crucial for reliable voice command performance in varying environments.
Area of Science:
- Acoustics
- Environmental Science
- Signal Processing
Background:
- Voice command systems are increasingly used in various environments.
- Sound propagation is influenced by meteorological conditions.
- Predicting voice command intelligibility requires understanding signal reception.
Purpose of the Study:
- To investigate the effect of meteorological conditions on voice command sound pressure levels (SPLs) and intelligibility.
- To compare received SPLs with the ISO 9613-2 outdoor sound propagation standard.
- To determine the impact of signal-to-noise ratio (SNR) on voice command intelligibility under different weather conditions.
Main Methods:
- Recorded voice command sound pressure levels (SPLs) up to 1500 m.
- Related received SPLs to meteorological conditions during sound propagation.
- Calculated signal intelligibility using the ANSI S3.5 standard.
- Analyzed intelligibility at low (<-9 dB), moderate, and high (>0 dB) SNRs.
Main Results:
- Meteorological conditions had minimal effect on intelligibility at very low or very high SNRs.
- At moderate SNRs, variations in received SPL due to weather significantly altered voice command intelligibility.
- Changes in intelligibility occurred rapidly (minutes) under upward refracting conditions.
- Predicting intelligibility in moderate SNR environments is challenging due to atmospheric variability.
Conclusions:
- Atmospheric sound propagation significantly affects voice command intelligibility, particularly at moderate SNRs.
- The variability in intelligibility necessitates advanced prediction models for reliable voice command operation.
- Further research is needed to account for dynamic meteorological effects on acoustic signals.
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