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  1. #1
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    Dithering to increase SNR [MATLAB]

    Hi,

    I'm currently evaluating my measurement hardware by means of its SNR behaviour. The circuit is designed to digitize a DC voltage. For test proposes I'm using a constant DC voltage.

    To increase the SNR for low analoge signal levels, I'm performing an averaging. This works as expected for low input signal amplitudes (low SNR) e.g. 100 samples +20dB SNR, 1k samples +30dB SNR and so on.
    What I have noticed, there is an "upper" limit. At this point the SNR doesn't increase by increasing the number of averaged samples. By having a look on the histogram of my raw (non-averaged) samples, there is a low number of gaussian distributed pins/frequencies.

    In my opinion the SNR can not by increased at this point as the deviation of the data is too low. So I think, a possebility to increase the SNR further would be dithering. Has anyone performed dithering in MATLAb so far? Would white gaussian noise with an amplitude of +-1/2 LSB be sufficient, or are there other distributions with a better performance?

    BR

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  2. #2
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    Re: Dithering to increase SNR [MATLAB]

    You rather want an uniform than a gaussian distribution for the dither signal.



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  3. #3
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    Re: Dithering to increase SNR [MATLAB]

    Hi FvM,

    thank you for your reply.

    So I will use an uniform distribution.

    THX



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