We can design a linear phase FIR filter using 2 methods:-Windowing and FSM(Frequency Sampling method). The aim of this experiment is to design a linear phase FIR filter using windowing method.In this method the input time domain infinite Digital Time signal is multiplied with a windowing function which is a finite DT signal, to obtain an FIR filter transfer function in the form of an array of values. There are different types of windowing functions. The choice of windowing function is decided by the value of stop band attenuation and Cn.
A Scilab code was used to design an FIR filter. Hanning window was the windowing function used .The stopband attenuation was decided accordingly. A low pass filter was designed and the observed and decided parameter values were compared.
A Scilab code was used to design an FIR filter. Hanning window was the windowing function used .The stopband attenuation was decided accordingly. A low pass filter was designed and the observed and decided parameter values were compared.
Rectangular Window function is not preferred because it has small value of stop band frequency.
ReplyDeleteYes the value of As for rectangular function is 21
DeleteBut it has minimum number of calculations..so it can be preferred over other windows based on the application.
ReplyDeleteThe trick is to select the window function that will give a filter with the correct transition width and attenuation in stopband.
ReplyDeleteYes..Value of transition width and the
ReplyDeleteAttenuation are the parameters on which window is selected.