METHOD AND APPARATUS FOR LOW COMPLEXITY NOISE REDUCTION

摘要

A method and apparatus for improving sound quality in a voice transmission or recording system is disclosed. The system involves controlling an amount of gain used in amplifying a signal wherein a nominal gain characteristic that is substantially invoked in the presence of a voice signal or information signal, while gain is decreased rapidly in the absence of a voice or information signal. A background noise characteristic assists in controlling the nominal gain characteristic. In an exemplary embodiment, a gain adjustable amplifier is gain controlled by a gain control signal that is the arithmetic product of an input signal derived from an environment that may contain background noise, as modulated by a background noise estimate signal. Amplification in the gain adjustable amplifier is thus controlled so that amplification of the input signal is adjusted so as to reduce the perceived background noise received by at a far end (i.e., transmitted).