VariSphear Microphone Array Measurement System
Analysis of directional acoustic room properties requires an appropriate method for three-dimensional aquisition of the sound field. Microphone arrays are suitable to gain directional focused output signals by appliance of adequate signal processing. Spherical microphone arrays are convenient due to their rotational symmetry. A powerful method to aquire directional focussed output signals is decomposition of the sampled sound field into spherical harmonics via spatial fourier transformation. The resulting coefficients can be fed to a modal beamformer. The modal beamformer facilitates beam steering and is widely independent from the geometric properties of the measurement system itself. The directional focused output signal of the Beamformer can be used for a large amount of further applications.
Orthnormal decomposition of array measurement data, spatial fourier transformation and extrapolation facilitate wave field reconstruction in a wide area. This method e.g. can be used to produce parameter sets for spatial auralisation via wave field synthesis or binaural synthesis.
See more details in: "Wellefeldanalyse mit sphärischen Mikrofonarrays", Master Thesis 2009, Benny Bernschütz.
A highly precise and variable virtual spherical microphone array has been designed and built at the acoustics laboratory of Prof. Dr.-Ing. Christoph Pörschmann.
VariSphear Variable Spherical Microphone Array
The VariSphear Measurement Systems delivers high quality measurement data for wide frequency range beamforming and spatial wave field decomposition/reconstruction.
For more detailed information contact: Benny Bernschütz
VariSphear Information [german]
Download Handout VariSphear Measurement System
VariSphear Software (Screenshots)
VariSphear wavecapture Main
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