Techniques are provided to suppress noise and interference using an array
microphone and a combination of time-domain and frequency-domain signal
processing. In one design, a noise suppression system includes an array
microphone, at least one voice activity detector (VAD), a reference
generator, a beam-former, and a multi-channel noise suppressor. The array
microphone includes multiple microphones--at least one omni-directional
microphone and at least one uni-directional microphone. Each microphone
provides a respective received signal. The VAD provides at least one
voice detection signal used to control the operation of the reference
generator, beam-former, and noise suppressor. The reference generator
provides a reference signal based on a first set of received signals and
having desired voice signal suppressed. The beam-former provides a
beam-formed signal based on a second set of received signals and having
noise and interference suppressed. The noise suppressor further
suppresses noise and interference in the beam-formed signal.