MATLAB: How to view the filter coefficients from thebandpass fitler desinged

filterMATLAB

Hello,

I designed a bandpass filter as below

d = fdesign.bandpass('N,F3dB1,F3dB2',40,500,1500,6000);
Hd = design(d,'butter');
fvtool(Hd)

But how to get(or see) these filter coefficients. Thanks.

Best Answer

The following will get you very close:

 Hd = fdesign.bandpass('N,Fc1,Fc2',40,500,1500,6000);
 B = design(Hd);

Compare

fvtool(B,1);
fvtool(BPF_coefficients,1)

Related Solutions

MATLAB: How to design FIR lowpass filter with cutoff frequency, fc1 = 20 Hz and FIR bandpass filter with cutoff frequency fc2 = 10 Hz and fc3 = 35 Hz.

Déjà vu

how to design IIR highpass filter with cutoff frequency of 20Hz and FIR bandpass filter with cutoff frequency of 10Hz and 15Hz?

Make the appropriate changes to get the cascaded filter you want.

MATLAB: Bandpass filter

Hi Magda, We need to know your sampling frequency to give some exact code, but I'll give you a general example and assume a sampling frequency.

I'll assume the data are sampled at 200 Hz. Again you need to use the correct sampling frequency. I'll simply choose to use 40 dB of attenuation in the stopband.

d = fdesign.bandpass('Fst1,Fp1,Fp2,Fst2,Ast1,Ap,Ast2',1,2,11,12,40,0.5,40,200);
Hd = design(d);
fvtool(Hd); % view the filter magnitude response
% filter data with filter()
output = filter(Hd,input);

Note that

    Hd = design(d,'butter');

gives a less expensive (computationally) IIR design. Depending on your sampling frequency and how much attenuation you need, your design can be very expensive.

Best Answer

Related Solutions

MATLAB: How to design FIR lowpass filter with cutoff frequency, fc1 = 20 Hz and FIR bandpass filter with cutoff frequency fc2 = 10 Hz and fc3 = 35 Hz.

MATLAB: Bandpass filter

Related Question