How to Bandpass filter an array and display its spectrum in frequency domain

[khahuras]

I have a lot of arrays, which is sampled at 128 Hz (that means the two consecutive values from the array have a time gap of 1/128 seconds).

Each array contains for about 70 values.

How can I display the spectrum analyzer (in frequency domain) of that array? Especially, how to bandpass filter that array and check the output array with its spectrum?

To check this, I can generate some sine-wave arrays of different frequencies and amplitudes in Labview > Signal Processing > Signal Generator > Sine wave, then sum all the arrays to have a signal arrays of different frequencies. But I don't know how to view its frequency domain and bandpass filter it.

Thanks in advanced.

[Chinmay_NI]

Hi,

There are inbuilt VIs for filtering and performing an FFT in LabVIEW. The quickest way to accomplish your task is to use express VIs, In your functions palette got to Express > Signal Analysis. IN this palette you can use Filter express VI to implement bandpass filter, and Spectral Express VI to perform an FFT and display the FFT spectrum on a graph.

[William1225]

Hi, khahuras,

I try to simulate some signals to implement the band pass filter.

Each IIR filter has its characteristics and the order also affect the result a lot.

I take the butterworth filter to extract the frequency I want, but the original frequency component of my program is seperate exactly,

in the real situation, maybe trial & error should be taken into account.

[marcus.branch]

What's up friend. Did you manage to solve this problem? I'm working with EEG signals too and I have this same problem and doubt to work on MATLAB.

If you can help me if you managed to solve it, I appreciate it

[altenbach]

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@marcus.branch wrote:
I'm working with EEG signals too and I have this same problem and doubt to work on MATLAB.

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This is the LabVIEW forum. If you have a Matlab question, there might be better places for that.