METHOD AND APPARATUS FOR REDUCING OR REMOVING CLICK NOISE

• US 20120207255A1
• Filed: 01/27/2012
• Published: 08/16/2012
• Est. Priority Date: 02/10/2011
• Status: Active Grant

• Current Assignee: NXP B.V. (NXP Semiconductors NV)
• Original Assignee: NXP B.V. (NXP Semiconductors NV)
• Inventors: Groot Hulze, Gertjan, Siemons, Jasper
• Granted Patent: US 8,855,252 B2
• Time in Patent Office: Days
• US Class Current: 375/346
• CPC Class Codes: H04B 1/1081 Reduction of multipath noise by equalising H04B7/005

Abstract

The invention relates to an apparatus and a method for detecting and correcting input signals regarding click noise, using a first detector unit and a second correction unit, the detector unit differentiates the input signal and extracts the noise signal and compares the sum of two noise samples with a threshold value and in case this sum exceeds the threshold value a click is observed, while the correction unit corrects the input signal in the phase domain and differentiates it prior to outputting the corrected signal.

Claims

1. Method for detecting and correcting input signals regarding click noise, using a first detector unit and a second correction unit, the detector unit differentiates the input signal and extracts the noise signal and compares the sum of two noise samples with a threshold value and in case this sum exceeds the threshold value a click is observed, while the correction unit corrects the input signal in the phase domain and differentiates it prior to outputting the corrected signal.

2. Method according to claim 1, wherein the detector unit performs at first a differentiation of the input signal and wherein the differentiation creates a signal which is optionally a MPX signal.

3. Method according to claim 1, wherein the extraction of noise of the signal takes place in a block, while the extraction will be realised such that a low pass filtered version of the signal will be subtracted from a delayed signal.

4. Method according to claim 1, wherein subsequently two consecutive noise samples will be added to create a further signal which will be used as a basis for the comparison with a predetermined threshold value such that in case the absolute value of the further signal exceeds the threshold value a click will be detected.

5. Method according to claim 1, wherein upon detection of a click a predetermined amount of phase samples causing the click will be corrected.

6. Method according to claim 5, wherein three phase samples causing the click will be corrected.

7. Method according to claim 1, wherein the method has been implemented within a digital signal processor.

8. Apparatus for at least reducing click noise from input signals comprising a first detector unit and a second correction unit, the detector unit differentiates the input signal and extracts a noise signal and compares a sum of two noise samples with a threshold value and in case this sum exceeds the threshold value a click is observable, while the correction unit corrects the input signal in the phase domain and differentiates it prior to outputting the corrected signal.

9. Apparatus according to claim 8, wherein the click noise is removed.