able, to a certain extent, to determine the location of a sound
source and to use this information to focus on a person speech while
ignoring the ambient noise.
Similarly, microphones arrays enable to locate sounds and filter them depending of their incoming direction. Unlike light, that propagates too fast to record travel times easily, time difference of arrival (TDOA) of a same sound recorded by two different microphones can be computed directly and used to detect the origin of a sound.Though microphone arrays are known since the 20s for military applications (aircraft detection, artillery localization), the tremendous increase in computational power as well as the miniaturization of microphones have opened new theories and algorithms – precise sound source localization through deconvolution, ambient noise filtering – and new areas of uses: sound filtering in telecommunications (laptops, smart-phones), industrial applications (optimization of airplanes design to reduce noise emission).
Meanwhile, widely spread arrays are nowadays limited to 2, 3 or 4 microphones and are unable to deal with complex situations like multiple speakers, room reverberation or diffraction due to large wavelength of audible sound waves.
In this project, a microphone array with a large number of elements has been built together with a fast middleware architecture that is able to record and stream sounds from 64 sources with low latency. Together with a standard optical camera, the array is able to compute an acoustic image of a scene and to superpose it with the optical image, in real-time.
Microphone arrays can not only localize sound sources but also amplify selectively one source and cancel out the others. The sound quality can be dramatically improved compared to single microphone recordings. This type of processing can be used to design smart hearing aids that automatically amplify an interesting sound source, for example the voice of your interlocutor, without amplifying background noise.
This project is supported by a Pioneer Fellowship.
You are interested to participate in the development of the next generation hearing aid? You want to know more about the capabilities of a microphone array? Do not hesitate to contact us!
We are recruiting a signal processing expert (MSc/PhD level). Contact us for more information.
If you are a student and are looking for a semester project/master thesis or a paid job, please have a look below or directly contact us if you have an other exciting idea.
Come with your own ideas or choose a subject in the list below:
Apr-Aug 2012 - M. Chareton - "Localizing sound sources using multiple microphone arrays". Award: Prix du stage de recherche 2012, École polytechnique, France
Apr-Aug 2012 - S. Humeau - "Study of the effect of near field scratching noises on a microphone array"
Last update: 15/01/2013
Diese Website wird in älteren Versionen von Netscape ohne graphische Elemente dargestellt. Die Funktionalität der Website ist aber trotzdem gewährleistet. Wenn Sie diese Website regelmässig benutzen, empfehlen wir Ihnen, auf Ihrem Computer einen aktuellen Browser zu installieren. Weitere Informationen finden Sie auf
The content in this site is accessible to any browser or Internet device, however, some graphics will display correctly only in the newer versions of Netscape. To get the most out of our site we suggest you upgrade to a newer browser.