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<div>Hello everyone, <br>
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<div>I am having a small issue with the DFT filter used to remove power line noise at 50 Hz. Even after applying the filter, I still observe line noise in the power spectral density.<br>
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I am using the <a href="https://www.fieldtriptoolbox.org/reference/preproc/ft_preproc_dftfilter" target="_blank" rel="noopener noreferrer" id="x_docs-internal-guid-7e102dd8-7fff-216a-4eb5-e44f5f4d3102" style="text-decoration:none"><span style="font-size:13pt; font-family:Arial,sans-serif,serif,"EmojiFont"; color:rgb(0,151,167); background-color:transparent; font-weight:700; font-style:normal; font-variant:normal; text-decoration:underline; vertical-align:baseline; white-space:pre-wrap">ft_preproc_dftfilter</span></a>
function from the Fieldtrip toolbox, which applies a narrow-band notch filter to eliminate the 50 Hz noise.</div>
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<p><span>Here is the snippet of code I am using</span></p>
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<div><b><span style="color:rgb(0,111,201)">%filtre the data </span><br>
<span style="color:rgb(0,111,201)"> cfg = [];</span><br>
<span style="color:rgb(0,111,201)"> cfg.hpfilter = 'yes'; % High-pass filter</span><br>
<span style="color:rgb(0,111,201)"> cfg.hpfreq = 1 ; % High-pass frequency</span><br>
<span style="color:rgb(0,111,201)"> cfg.dftfilter = 'yes'; % enable notch filtering to eliminate power line noise</span><br>
<span style="color:rgb(0,111,201)"> cfg.dftfreq = [50]; %set frequencies for notch filtre</span><br>
<span style="color:rgb(0,111,201)"> dataContinuousResampled_filtred = ft_preprocessing(cfg,dataContinuousResampled);</span><br>
<span style="color:rgb(0,111,201)"> </span><br>
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<div>If you have any suggestions, please let me know. <br>
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<b>Hasnae Agouram<br>
PhD student</b><br>
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