A three-microphone system for real-time directional analysis: toward a device for environmental monitoring in deaf-blind.
Sound localization is a problem for the hearing impaired, deaf, and deaf-blind. A laboratory prototype of a three-microphone digital system for real-time directional analysis of sound sources that is mounted on eyeglasses has been developed. A cross-correlation algorithm is used for determinations of time and phase differences between the three microphone signals. The equipment was evaluated in a sound-treated test room with noise and speech stimuli from 12 different directions. It has an adequate precision (within approximately +/- 10 degrees) for speech and noise bursts in the frequency range 0.5-4 kHz, and for testing with words in a sound field the error percentage is very close to 0 at 0-degrees azimuth. The robustness of the algorithm in terms of signal-to-noise ratio is documented and reaches about +8 dB in different directions for speech and up to 0 dB for noise bursts. It is concluded that the construction of a robust system for directional analysis with sufficient efficiency for further experiments has been achieved.
Borg
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E
Ahlsén Research Institute, Orebro Medical Centre Hospital, Sweden. anita.dandenell@orebroll.se
Neovius
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L
Kjellander
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M
D000465:Algorithms; D001766:Blindness; D003638:Deafness / Q000534:rehabilitation*; D004784:Environmental Monitoring; D006801:Humans; D012682:Sensory Aids; D013017:Sound Localization; D014732:Vibration