  In this paper a generalized postfilter algorithm design issues are presented.
This postfilter is used to jointly suppress late reverberation, residual echo,
and background noise. When residual echo and noise are suppressed, the best
result obtains by suppressing both interferences together after the Acoustic
echo cancellation (AEC). The main advantage of this approach is that the
residual echo and noise suppression does not suffer from the existence of a
strong acoustic echo component. Furthermore, the Acoustic echo cancellation
(AEC) does not suffer from the time-varying noise suppression. A disadvantage
is that the input signal of the Acoustic echo cancellation (AEC) has a low
signal-to-noise ratio (SNR). To overcome this problem, algorithms have been
proposed where, apart from the joint suppression, a noise-reduced signal is
used to adapt the echo canceller.
