Thread Subject: Bandpass Filter - Simulink

Hi,

I have a simple model, in that i am adding 3 sine waves of 5Hz, 10Hz and 20Hz frequencies. The resultant wave, i am passing it through a bandpass filter which has to pass only frequencies between 8-12 Hz and block rest all. But which is not happening. For the same i am using the bandpass filter block of signal processing blockset.

I tried to set the frequencies both in normalized way as well as normal way (using Hz).
At the output spectrum i will see peak at all the 3 input frequencies. But i suppose to get peak at only desired freq.

Can anyone help me in setting the parameters of bandpass filter.

Thanks,
Ashwini

Hi Ashwini,

What sampling rate are you using for the three sine waves? Are you setting
the sampling rate for the filter to the same value?

HTH.

Rick



"Ashwini Deshpande" <vd.ashwini@mathworks.com> wrote in message
news:hdiruh$h9f$1@fred.mathworks.com...
> Hi,
>
> I have a simple model, in that i am adding 3 sine waves of 5Hz, 10Hz and
> 20Hz frequencies. The resultant wave, i am passing it through a bandpass
> filter which has to pass only frequencies between 8-12 Hz and block rest
> all. But which is not happening. For the same i am using the bandpass
> filter block of signal processing blockset.
>
> I tried to set the frequencies both in normalized way as well as normal
> way (using Hz).
> At the output spectrum i will see peak at all the 3 input frequencies. But
> i suppose to get peak at only desired freq.
>
> Can anyone help me in setting the parameters of bandpass filter.
>
> Thanks,
> Ashwini

"Rick Rosson" <no.spam@spammer.abc> wrote in message <hdjtfo$3m$1@fred.mathworks.com>...
> Hi Ashwini,
>
> What sampling rate are you using for the three sine waves? Are you setting
> the sampling rate for the filter to the same value?
>
> HTH.
>
> Rick

Thanks ..
even after setting the Fs of BPF same as sampling frequency of waves, the effect of other frequencies is still there.
If required i can mail my model.

-- Ashwini