Patent ID: 9318125
Filing Date: 2016-04-19
CPC Classification: G10L

Claim Text:
1. A noise reduction device configured for use in a radio communication device comprising: an input configured to receive an audio signal comprising a representation having a plurality of power envelopes; wherein the audio signal consists of a noise-free speech component and a tonal noise component; a tonal noise detection circuit configured to estimate a tonal noise probability based on a first indicator and a second indicator; wherein the first indicator represents an amount of the tonal noise component in the audio signal based on a magnitude of difference between a maximum power envelope and a minimum power envelope; wherein the second indicator represents a ratio of the largest spectral peak within a frequency range between 501 Hz to 1 KHz as compared to the largest spectral peak within a frequency range between 0 Hz to 500 Hz; memory for storing the first indicator and a predetermined range for the first indicator and for storing the second indicator and a predetermined threshold for the second indicator; a noise reduction circuit configured to reduce the tonal noise component within the audio signal when the first indicator is outside the predetermined range for the first indicator and when the second indicator is above the predetermined threshold; and an output configured as an audio signal comprising a reduced amount of the tonal noise component.