bandpass filter

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Mon, 06/24/2013 - 06:16 am

hello,

how can i easily create a bandpass filter (for frequencies between 150 and 250 Hz) in Igor?

thanks
Set your data's X scaling to match the sampling frequency, then choose Analysis->Filter... to design and apply the bandpass filter.

--Jim Prouty
Software Engineer, WaveMetrics, Inc.

June 24, 2013 at 10:14 am - Permalink

thanks for your comment. however, its unclear to me how to use the filter dialogue to create a bandpass filter. there is only a low pass, high pass and notch filter. can you elaborate in more detail on how to use the dialogue to create a 150 to 250 Hz bandpass filter? thanks a lot

June 25, 2013 at 01:20 am - Permalink

miro wrote:
thanks for your comment. however, its unclear to me how to use the filter dialogue to create a bandpass filter. there is only a low pass, high pass and notch filter. can you elaborate in more detail on how to use the dialogue to create a 150 to 250 Hz bandpass filter? thanks a lot


A bandpass filter is simply a lowpass and highpass filter together. Just check both boxes.

What's your signal's sampling rate? Knowing this is essential.

--Jim Prouty
Software Engineer, WaveMetrics, Inc.

June 25, 2013 at 10:47 am - Permalink

Enter 2000 in the "Design using this Sampling Frequency (Hz)" field.

Then set the high pass frequencies to around 150, and the low pass frequencies to around 250 Hz. See the attached screen capture of the Filter Design panel.

--Jim Prouty
Software Engineer, WaveMetrics, Inc.
BandPassFIRFs2000Hz.PNG

June 28, 2013 at 03:44 pm - Permalink