During this lab session we needed to perform FIR using Frequency sampling for LPF and HPF and BPF. It was implemented in Scilab.As filter order increases, number of lobes in stop band also increases. The output is also symmetric in nature.
In this the desired frequency response Hd(w) is sampled at w=(2*pi*k)/N and the frequency samples thus obtained are taken as DFT coefficients. FIR filter with impulse response is then calculated by IDFT.
We observed that the stop band attenuation values computed in the code are close to the values taken as input. We also looked at the magnitude plots and observed the presence of lobes in the stop band for low pass filter .
https://drive.google.com/open?id=0B8F3pY6H1pIWRHVRbnBZMnVqUDg
http://preranasarode1995.blogspot.com/2016/04/fir-filter-design-using-frequency.html
In this the desired frequency response Hd(w) is sampled at w=(2*pi*k)/N and the frequency samples thus obtained are taken as DFT coefficients. FIR filter with impulse response is then calculated by IDFT.
We observed that the stop band attenuation values computed in the code are close to the values taken as input. We also looked at the magnitude plots and observed the presence of lobes in the stop band for low pass filter .
https://drive.google.com/open?id=0B8F3pY6H1pIWRHVRbnBZMnVqUDg
http://preranasarode1995.blogspot.com/2016/04/fir-filter-design-using-frequency.html
The perfect invertability of the Fourier transform is an important property for building filters which remove noise or particular components of a signals spectrum.
ReplyDeleteFSM is Faster than Windowing method for fir filter designing
ReplyDeleteFSM is Faster than Windowing method for fir filter designing
ReplyDeleteOnly if you have many parallel processors that FSM is faster than Windowing.
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