convolution

[mbartkow at ET.PUT.Poznan.PL]

Martin,

Deconvolution is a very common technique in DSP world. It make wonders if properly
implemented. To avoid the singularities of the inverted signal spectrum I would 
recommend to look at the Wiener filtering algorithm. His trick is to bias the whole 
spectrum by a very small amount and thus eliminate the division by zero problem.

Quite another approach is to calibrate your speaker+microphone using sine waves first,
which should be performed in possibly neutral and echoless environment (some kind of
desert ;-)) and then generate the impulse using an artificial signal reproduced by
your speaker.

MB