Techniques for canceling echo and suppressing noise using an array microphone
and signal processing. In one system, at least two microphones form an array microphone
and provide at least two microphone input signals. Each input signal may be processed
by an echo canceller unit to provide a corresponding intermediate signal having
some echo removed. An echo cancellation control unit receives the intermediate
signals and derives a first gain used for echo cancellation. A noise suppression
control unit provides at least one control signal used for noise suppression based
on background noise detected in the intermediate signals. An echo cancellation
and noise suppression unit derives a second gain based on the control signal(s),
cancels echo in a designated intermediate signal based on the first gain, and suppresses
noise in this intermediate signal based on the second gain. The signal processing
may be performed in the frequency domain.