Multichannel spatial auditory display for speech communications

Begault, D. R.; Erbe, T.; Wenzel, E. M.

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Multichannel spatial auditory display for speech communications

Begault, D. R.·Erbe, T.·Wenzel, E. M.

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Abstract

A spatial auditory display for multiple speech communications was developed at NASA/Ames Research Center. Input is spatialized by the use of simplified head-related transfer functions, adapted for FIR filtering on Motorola 56001 digital signal processors. Hardware and firmware design implementations are overviewed for the initial prototype developed for NASA-Kennedy Space Center. An adaptive staircase method was used to determine intelligibility levels of four-letter call signs used by launch personnel at NASA against diotic speech babble. Spatial positions at 30 degrees azimuth increments were evaluated. The results from eight subjects showed a maximum intelligibility improvement of about 6-7 dB when the signal was spatialized to 60 or 90 degrees azimuth positions.

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NASA Discipline Space Human Factors NASA Discipline Number 06-10 NASA Center ARC NASA Program Space Human Factors Engineering Equipment Design Computers Speech Intelligibility Human Engineering Software Communication Evaluation Studies Psychoacoustics Auditory Perception Man-Machine Systems Human Female Male

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Begault, D. R., Erbe, T., Wenzel, E. M.. 1994-10-01. Multichannel spatial auditory display for speech communications. https://ntrs.nasa.gov/citations/20040089768

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