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    [Moved]: How to remove noise from an eeg signal contaminated with noise?

    i need to remove noise from th eeg signal using a notch filter.Can anyone please help me with the coding?

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    Re: How to remove noise from an eeg signal contaminated with noise?

    Coding? Do you mean you want a DIGITAL filter? Your question is pretty vague. Frequency? Bandwidth? Order? Sampling frequency? Programming language? Other requirements?



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    Re: How to remove noise from an eeg signal contaminated with noise?

    They were assigning this problem in sophomore circuits
    classes when I was an undergrad (30+ years ago). Nice
    to know universities are keeping up (by moving the
    problem to DSP... yeh.



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    Re: How to remove noise from an eeg signal contaminated with noise?

    yes sir,i agree with u..I questioned in a vague manner without mentioning any information.
    Sir firstly i initiated with a raw eeg data which i had taken from .mat file..Then i added noise to it..Now i want to filter that noise either by a filter that produces the best kind of results..The code for the above mentioned steps is given below:
    Code PHP - [expand]
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    fs = 512 
    T = 1/fs;
    N =length(EEGsig); ls = size(EEGsig);
    tx =[0:length(EEGsig)-1]/fs;
    fx = fs*(0:N/2-1)/N;
    ax=1;
    x=  EEGsig;
    fNoise = 50;    
    aNoise = 0.25;  
    noise= aNoise*x;
    signalNoise= x + noise;
    figure();
    subplot(3,1,1);
    plot(tx, x);
    xlabel('Time [s]'); 
    ylabel('Amplitude');
    title('Original signal');
    subplot(3,1,2);
    plot(tx, noise);
    xlabel('Time [s]');
    ylabel('Amplitude');
    title('Noise');
    subplot(3,1,3);
    plot(tx, signalNoise);
    xlabel('Time [s]');
    ylabel('Amplitude');
    title('Original signal + Noise');
    hence,in the above code i need to filter the added noise..Please help me with the code..N thanks for your reply sir.



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    Re: [Moved]: How to remove noise from an eeg signal contaminated with noise?

    Matlab has a lot of tools for filtering. Try searching "matlab filters".



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  6. #6
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    Re: [Moved]: How to remove noise from an eeg signal contaminated with noise?

    sir basically i want to use notch filter for removing noise.Can u help me with the syntax or the code itself?



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    Re: [Moved]: How to remove noise from an eeg signal contaminated with noise?

    Quote Originally Posted by Aparna24 View Post
    sir basically i want to use notch filter for removing noise.Can u help me with the syntax or the code itself?
    I think you need to practice your Google-Fu, it's very weak at the moment...

    e.g. first returned link https://www.mathworks.com/help/dsp/ref/iirnotch.html
    third link: https://www.mathworks.com/help/dsp/e....mathworks.com

    Though I have no idea how a notch filter will help you remove noise...unless that noise is at a fixed frequency, but then I wouldn't call that noise.



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    Re: [Moved]: How to remove noise from an eeg signal contaminated with noise?

    Thanks for your suggestion and also for your reply..I have recently joined here,and so m not well qualified as you are..Though i'll try to improve n work upon my Google-Fu..



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