Patent Review

Subject: Noise reduction

 Topic: Noise Reduction System

The systems using wideband signals like speech use a filterbank and a running cross-correlator to detect narrowband frequencies and analysis-synthesis filterbank to attenuate the wideband signal, in which narrowband frequencies are not detected and to pass or amplify bands narrowband frequency components are detected. In this, narrowband frequencies are not detected.
Cross-correlations are obtained from output of two bandpass filters. Low cross-correlation value indicate lesser noise in the signal, while high value of cross-correlation indicate only noise is present.

Claims:
1. The system should consist of a first filter with first output and first frequency, and a second filter with second output and second frequency. These have to be 180degrees out of phase around third frequency. These signals are passed through running cross-correlator, which is interconnected to a low-pass filter, and analysis-synthesis filter.
2. The said first filter output and said second filter output are transformed with a saturated non-linearity component function prior to performing said running cross-correlation.
3. The filtering comprises of the step of amplifying said wideband signal at said third frequency if said running cross-correlation has a low value.

Comments

  1. Ankur Mahadik25 April 2017 at 22:27

    very much informative

    ReplyDelete
  2. $oM€$h25 April 2017 at 22:27

    Can be used in voice recognition systems where external noise is the major issue

    ReplyDelete
  3. Unknown25 April 2017 at 22:32

    what are the real time industrial applications?

    ReplyDelete
    Replies
    1. Unknown25 April 2017 at 22:42

      Noise reduction techniques can be useful in speech recognition systems where audio signal can be comparred with a pre stored signal in the database.

      Delete
  4. Unknown25 April 2017 at 22:37

    This real time application is very useful

    ReplyDelete
  5. Unknown25 April 2017 at 22:43

    Adaptive filters can be used

    ReplyDelete
  6. Unknown25 April 2017 at 22:47

    Noise reduction is implemented on small recording devices. Here, signal processors are used. IIR filters can be used due to their feedback.

    ReplyDelete
  7. Unknown25 April 2017 at 22:48

    informative

    ReplyDelete
  8. Siddhesh25 April 2017 at 23:26

    Very helpful review on 1-D signal processing

    ReplyDelete
  9. Chaitanya S28 April 2017 at 06:14

    Is useful for sound of clean channel in electric guitar

    ReplyDelete

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