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Active stereo sound localization.

Greg L Reid·Evangelos Milios
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Abstract

Estimating the direction of arrival of sound in three-dimensional space is typically performed by generalized time-delay processing on a set of signals from a fixed array of omnidirectional microphones. This requires specialized multichannel A/D hardware, and careful arrangement of the microphones into an array. This work is motivated by the desire to instead only use standard two-channel audio A/D hardware and portable equipment. To estimate direction of arrival of persistent sound, the position of the microphones is made variable by mounting them on one or more computer-controlled pan-and-tilt units. In this paper, we describe the signal processing and control algorithm of a device with two omnidirectional microphones on a fixed baseline and two rotational degrees of freedom. Experimental results with real data are reported with both impulsive and speech sounds in an untreated, normally reverberant indoor environment.

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AlgorithmsAnalog-Digital ConversionEquipment DesignHumansMicrocomputersPhoneticsSignal Processing, Computer-AssistedSound LocalizationTransducersJournal Article

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Greg L Reid, Evangelos Milios. 2003. Active stereo sound localization.. https://doi.org/10.1121/1.1518469

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