A physical method for estimating speech intelligibility in a reverberant sound field
Abstract
The MTF-STI method which is a physical method for measuring the quality of speech-transmission in a tunnel was investigated and it appears that the STI, which can be deduced from the MTF, correlates highly with the sound articulation score. The character of the information loss represented by the MTF, and the calculating system of the MTF are considered. In this system the effect of the reverberation on the MTF is calculated from the impulse response in a tunnel, and the effect of the noise separate from the effect of the reverberation is considered. The MTF is converted to the STI (Speech Transmission Index), which corresponds directly to the speech intelligibility. Essentially the STI represents an extension of the Articulation Index (AI) concept, therefore we determine the values of the parameters used in the STI calculation from the parameters of the AI for Japanese. Resulting STI correlates highly with the -log(1-s), where s is a sound articulation score. The data suggest that the STI may serve as a convenient predictor of speech intelligibility in a tunnel.
- Publication:
-
In its Res. Rept. of the Faculty of Eng
- Pub Date:
- December 1984
- Bibcode:
- 1984rrfe.nasa...79O
- Keywords:
-
- Signal Transmission;
- Speech;
- Transfer Tunnels;
- Verbal Communication;
- Acoustic Propagation;
- Acoustics;
- Correlation;
- Reverberation;
- Signal Reception;
- Speech Recognition;
- Communications and Radar