Method for suppressing noise in an acoustic signal for a multi-microphone audio device operating in a noisy environment

Abstract

Provided is a method for suppressing noise in an acoustic signal for a multi-microphone audio device operating in a noisy environment. The method comprises steps of: a) partitioning (10, 16) the spectrum of the noisy signal into a HF part and a LF part; b) operating denoising processes in a differentiated manner for each of the two parts of the spectrum with, for the HF part, a denoising by prediction of the useful signal from one sensor to the other between sensors of a first sub-array (R1), by means of a first adaptive algorithm estimator (14), and, for the LF part, a denoising by prediction of the noise from one sensor to the other between sensors of a second sub-array (R2), by means of a second adaptive algorithm estimator (18); c) reconstructing the spectrum by combining together (22) the signals delivered after denoising of the two parts of the spectrum, respectively; and d) selectively reducing the noise (24) by an Optimized Modified Log-Spectral Amplitude gain, OM-LSA, process.

Description

Technical field [0001] The present invention relates to language processing in noisy environments. [0002] In particular, the present invention relates to the processing of speech signals picked up by "hands-free" type telephone equipment intended for use in noisy environments. Background technique [0003] Such devices include one or several sensitive microphones, which not only pick up the user’s voice, but also pick up environmental noise. Environmental noise constitutes an interfering element. In some cases, this interfering element can even make the speaker’s The words are difficult to understand. The same is true if it is desired to implement speech recognition technology, because it is very difficult to shape the speech embedded in high-level noise. [0004] This difficulty associated with environmental noise is particularly restrictive in the case of "hands-free" devices in motor vehicles, regardless of whether these devices are in removable boxes that integrate all signal...

AI Technical Summary

Problems solved by technology

[0019] The problem of the present invention is to access, in this context, efficient noise reduction techniques to deliver to a remote speaker a speech signal representing the language spoken by a nearby speaker (the driver of the headset wearer's car), which is obtained from Cleaning out the signal from the spurious portion of the external noise present in the environment near the speaker is performed where this technique:

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