Time Domain Signal Filters - Can anyone please help?

[molderon]

Hi,

I would like to filter my ECG sampled signal (2000Hz). Which filter
should i use to clean the 60Hz noise?

I have some other artifcats, how should i filter them?

Many Thanks

[Nann]

1. If the frequency of 60Hz noise does not change, you can use a notch filter to remove the noise.  There is VIs in the LabVIEW Digital Filter Design Toolkit to design notch filter.

2. If you can aquire the 60Hz noise as a reference signal, you can use adaptive filter to remove the noise.

3. What are your "other artifacts"?

[molderon]

Nann wrote:
> 1. If the frequency of 60Hz noise does not change, you can use a notch filter to remove the noise.  There is VIs in the LabVIEW Digital Filter Design Toolkit to design notch filter.
> 2. If you can aquire the 60Hz noise as a reference signal, you can use adaptive filter to remove the noise.
> 3. What are your "other artifacts"?
>  
>  

Hi Nann,

1. Im afraid that i dont have the DFD tool kit (I am using LV 7.1), Do
you happen to know if i can download it from ni website?
2. Thanks, I will try to see if i can acquire the 50-60Hz noise signal
3. my main artifact is baseline drifting of my ECG signal..

Many Thanks

[Nann]

Here are more information about the DFDT. http://www.ni.com/toolkits/df_design_toolkit.htm

Regarding the baseline drifting, probably you can use highpass filter, polynomial or wavelet-based detrending.  Do you have a sample signal that I might try with?

[molderon]

Hi Nann,

Thanks.

I have an ASCII ecg signal (Time domain) with 4000 points, i belive.
my sampling rate is 2000 points per second (each point = 0.5ms)

Where do i send the file to?

Appriciate the help..

[Nann]

Hi Molder,

Can you attach the file to this thread?

Thanks

Nann

[molder]

Hi Nann

Attached

[molderon]

Hi,

I post the file in NI forum. Please let me know if you cannot view it

Thanks, Nann

[Nann]

I tried to remove the baseline with the wavelet-based method.  I looks good.  I used the WA Detrend VI from the LabVIEW Advanced Signal Processing Toolkit 7.5.  Attached are the VI and screenshot.  I have two questions here:

(1) Is the sampling rate really 2000 samples per second?  It seems not because the heart rate will be 360 beat per second when the sampling rate is 2000 samples per second.

(2) I don't see the 60Hz noise in the ECG signal. 

[molder]

Thanks!

Can you save it in LV 7.1? I got an error message when openning any 8.2 files

I will try to find another signal with 60hz noise in it