| 摘要 |
Near-field sensing of wave signals, for example for application in headse ts and earsets, is accomplished by placing two or more spaced-apart micropho nes along a line generally between the headset and the user's mouth. The sig nals produced at the output of the microphones will disagree in amplitude an d time delay for the desired signal - the wearer's voice - but will disagree in a different manner for the ambient noises. Utilization of this differenc e enables recognizing, and subsequently ignoring, the noise portion of the s ignals and passing a clean voice signal. A first approach involves a complex vector difference equation applied in the frequency domain that creates a n oise-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. Th e two approaches can be applied separately or combined.
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