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.
•In practice, a matrix of impulse responses is
measured, and the matrix has to be
numerically inverted (usually employing some regularization technique).
•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.)