36,287 research outputs found
Recommended from our members
The influences of environmental conditions on source localisation using a single vertical array and their exploitation through ground effect inversion
The performance of microphone arrays outdoors is influenced by the environmental conditions. Numerical simulations indicate that, while horizontal arrays are hardly affected, direction-of-arrival (DOA) estimation with vertical arrays becomes biased in presence of ground reflections and sound speed gradients. Turbulence leads to a huge variability in the estimates by reducing the ground effect. Ground effect can be exploited by combining classical source localization with an appropriate propagation model (ground effect inversion). Not only does this allow the source elevation and range to be determined with a single vertical array but also it allows separation of sources which can no longer be distinguished by far field localization methods. Furthermore, simulations provide detail of the achievable spatial resolution depending on frequency range, array size and localization algorithm and show a clear advantage of broadband processing. Outdoor measurements with one or two sources confirm the results of the numerical simulations
Joint model-based recognition and localization of overlapped acoustic events using a set of distributed small microphone arrays
In the analysis of acoustic scenes, often the occurring sounds have to be
detected in time, recognized, and localized in space. Usually, each of these
tasks is done separately. In this paper, a model-based approach to jointly
carry them out for the case of multiple simultaneous sources is presented and
tested. The recognized event classes and their respective room positions are
obtained with a single system that maximizes the combination of a large set of
scores, each one resulting from a different acoustic event model and a
different beamformer output signal, which comes from one of several
arbitrarily-located small microphone arrays. By using a two-step method, the
experimental work for a specific scenario consisting of meeting-room acoustic
events, either isolated or overlapped with speech, is reported. Tests carried
out with two datasets show the advantage of the proposed approach with respect
to some usual techniques, and that the inclusion of estimated priors brings a
further performance improvement.Comment: Computational acoustic scene analysis, microphone array signal
processing, acoustic event detectio
- …