Equalization of the Measuring System Frequency Response in the Objective Assessment of Speech Intelligibility

Authors

DOI:

https://doi.org/10.18372/1990-5548.69.16428

Keywords:

speech intelligibility, room impulse response, frequency response equalization, audio equipment of non-professional quality level

Abstract

Voice control of an unmanned aerial vehicle has a number of advantages if the operator is indoors. In this case, the distortions of speech commands caused by the influence of noise interference can be significantly reduced. However, the disadvantage of such control is the negative impact of reverberation on speech intelligibility. Therefore, it is advisable to perform a preliminary assessment of speech intelligibility in the room before the session of unmanned aerial vehicle controlling. This assessment can be performed by the modulation method, using the room impulse response estimate. If a non-professional quality loudspeaker and microphone are used to estimate the room impulse response, errors in the room impulse response estimate can affect the results of speech intelligibility assessment. In this paper, two techniques of equalizing of non-professional quality level audio equipment used in assessing the room impulse response have been compared. It is shown that a dividing the frequency response of the “loudspeaker-room-microphone” system into the amplitude frequency response of the “loudspeaker-microphone” subsystem provides almost the same equalization quality as a more complex technique of adaptive filtering. At the same time, studies have shown that such equalization is not necessary, provided that the frequency response unevenness of the “loudspeaker-microphone” subsystem does not exceed 8–10 dB in the frequency range from 100 Hz to 11 kHz.

Author Biography

Arkadiy Prodeus , National Technical University of Ukraine “Ihor Sikorsky Kyiv Polytechnic Institute”

Department of Acoustic and Multimedia Electronic Systems

Doctor of Engineering Sciences. Professor

References

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Published

2021-12-21

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TELECOMMUNICATIONS AND RADIO ENGINEERING