title: A three-microphone system for real-time directional analysis: toward a device for environmental monitoring in deaf-blind.
abstract: 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.
authors.affiliation: Ahlsén Research Institute, Orebro Medical Centre Hospital, Sweden. anita.dandenell@orebroll.se
authors.forename: E
authors.initials: E
authors.lastname: Borg
authors.forename: L
authors.initials: L
authors.lastname: Neovius
authors.forename: M
authors.initials: M
authors.lastname: Kjellander
mesh_terms: D000465:Algorithms; D001766:Blindness; D003638:Deafness / Q000534:rehabilitation*; D004784:Environmental Monitoring; D006801:Humans; D012682:Sensory Aids; D013017:Sound Localization; D014732:Vibration