Near-field sensing of wave signals, for example for application in headsets and earsets, is accomplished by placing two or more spaced-apart microphones along a line generally between the
headset and the user's mouth. The signals produced at the output of the microphones will disagree in amplitude and time
delay for the desired
signal-the wearer'
s voice-but will disagree in a different manner forthe ambient noises. Utilization of this difference enables recognizing, and subsequently ignoring, the
noise portion of the signals and passing a clean voice
signal. A first approach involves a complex vector difference equation applied in the
frequency domain that creates a
noise-reduced result. A second approach creates an attenuation value that is proportional to the complex vector difference,and applies this attenuation value to the original
signal in order to effect a reduction of the
noise. The two approaches can be applied separately or combined.