‘I to do it by applying some moving average filter or band pass filter, etc.?’
That depends entirely on the nature of the noise. None of those will work with broadband noise because they are all essentially frequency-selective filters. For broadband noise, use the Savitzky-Golay filter (Signal Processing Toolbox sgolayfilt function), or the 'sgfilt' option in the smoothdata function. Wavelet denoising is also an option.
The best way to determine if the noise is band-limited is to first takt the fft of it. That plot will tell you.
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