The aim
of the exp was to design linear phase FIR filter using window function.In this
experiment we used hamming window function to design Low pass/high pass fiter
and Bandpass/band stop filter. We plotted magnitude as well as phase response.
.There
are different types of windowing functions Rectangular ,Bartlett ,Hamming
,Hanning, and Blackman.The specifications of As,Ap, stop band frequency,
passband frequency and sampling frequency are taken from the user.It is
observed that as the order of the filter increases the number of lobes in
frequency response increase.The attenuation depends upon the type of window
used. s we take window function with higher As value, the side lobe
width goes on decreasing with increasing main lobe width. The phase response of
the filter is linearly varying with frequency and no distortion is
observed in the output.
How do you select the window to be used for designing the filter??
ReplyDeleteAliasing can occur in the windowing method
ReplyDeleteRightly mentioned as window selection depends on the application where through which As value is one of the parameter responsible for selection of window
ReplyDeleteThe basic idea behind the window design is to choose a proper ideal frequency-selective filter and then to window its impulse response to obtain a linear-phase and causal FIR filter
ReplyDeleteWindow functions are preferable because they allow different window functions
ReplyDeletewhich can be used as per the design specifications of filter
Deciding window function depends on the input parameters
ReplyDeleteBlackmann window is the best since it has the highest attenuation in the stop band
ReplyDeleteRectangular window function is,however, the easiest and simplest to implement.
ReplyDeleteWindowing methods decide the characteristics of the filter that has to be designed.Hence it is preferred if compared to FSM.
ReplyDeleteOne of the better methods for FIR filters
ReplyDelete