Bandpass filter of cFP input signal

Hi,
I have a continuous input signal from analog compact field point. In normal, the input signal is steady, but it may oscillate sometimes. I would like to detect the oscillation frequency (0.5HZ~2HZ), that means I have to build a bandpass filter to keep the signal in 0.5 to 2 hz. Is anyone have better idea to implement this function? Thsnks for help.
Fred

Fred,
Here is a small example on Point by Point filtering. The point by point VIs allow you to perform filtering and other DSP operations one sample at a time. The example uses a butterworth filter that will give you the flattest amplitud response.
Please take a look at the example and let me know if you have any questions.
Regards,
Juan Carlos
N.I.
Attachments:
PtbyPt_FIlter.vi ‏35 KB

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Message Edited by vani on 07-24-2008 01:37 PM
Attachments:
filt_question2.vi ‏35 KB

Hi Vani,
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Cascade Form IIR Filtering
Digital Filter Design Toolkit
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Attachments:
Bandpass Filter.png ‏18 KB
Bandpass Filter Output.png ‏13 KB

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Hello @fbinim,
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pulse_PLL.vi ‏27 KB

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Message Edited by Matt A on 04-09-2008 03:55 PM
Matt Anderson
Hardware Services Marketing Manager
National Instruments
Attachments:
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