Digital Signal Processing Reference
In-Depth Information
where and are the power spectra of the speech signal at
its source position, the noisy speech signal at microphone position and
the noise signal at its source position, respectively. (The frequency index
will be omitted in the rest of paper.) Consequently, the corresponding
log-power-spectrum of the signals at the
microphone positions are
given by
Figure 19-1.
Signal captured through distributed microphones.
The derivative of
can be calculated by
Where
and
are given by
Note that both and are the functions of the ratio between signal
and noise at their source positions, i.e.,
S/N.
Small deviations of the
log-power-spectrum of the signal at the microphone position can be
approximated by a two-dimensional Taylor series expansion around
i.e.,
