Spinoff Company of
The University of Parma
Computation of filter coefficients
•No theory is assumed: the set of hi,j filters are derived directly from a set of impulse response measurements, designed according to a least-squares principle.
•STEP1: a matrix C of impulse responses is measured,
•STEP2: the target polar pattern P of the virtual microphone is defined
•STEP3: the processing filters H are found by imposing that
and inverting the matrix.
•This way, the outputs of the microphone array are maximally close to the ideal responses prescribed
•This method also inherently corrects for transducer deviations and acoustical artifacts (shielding, diffractions, reflections, etc.)
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