How to apply Bandstop IIR Digital filter to the 60Hz Noisy ECG Signal??

Hi every one..

I has designed a bandstop IIR filter to removed 60 Hz Sinus Noise at ECG
signal.
The step of I have done are :

1. Designed a bandpass filter (frequency domain) -> it will be H
2. Do FFT to the ECG Signal -> it will be X
3. Do the circular convolution -> Y = X.*H

But my question is : the output of Y is WRONG, because the result of X by
FFT is SYMMETRIC , but H is not symmetric. 
Please help to let me know how to apply the bandstop to the signal???

Thanks in advance

>> but H is not symmetric. 

it should be, otherwise you'll get a complex-valued output time domain
waveform from real-valued input.

On Sun, 18 Dec 2011 13:32:30 -0600, wongjowo wrote:

> Hi every one..
> 
> I has designed a bandstop IIR filter to removed 60 Hz Sinus Noise at ECG
> signal.
> The step of I have done are :
> 
> 1. Designed a bandpass filter (frequency domain) -> it will be H 
2. Do FFT to the ECG Signal -> it will be X 
3. Do the circular convolution -> Y = X.*H
> 
> But my question is : the output of Y is WRONG, because the result of X
> by FFT is SYMMETRIC , but H is not symmetric. Please help to let me know
> how to apply the bandstop to the signal???

Huh?

You've said nothing at all about Y, only about the symmetry of X and H.  
Yes, the impulse response of an IIR filter is not symmetric -- so?

-- 
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My conservative friends think I'm a liberal kook.
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Tim Wescott, Communications, Control, Circuits & Software
http://www.wescottdesign.com