FIR filter design using window function

In this experiment, we design a linear phase FIR filter - low pass and high pass. In this experiment, the desired impulse response is multiplied with window function w (n) to obtain h (n) which after Z-transform yields the transfer function H (z).

There are many types of window function i.e. Rectangular, Bartlett, Hamming, Hanning and Blackman. Attenuation in stop band is maximum for Blackman window and minimum for Rectangular window.

Various parameters like Ape, As, stop band frequency, pass band frequency and sampling frequency are taken as inputs from the user. It was observed that as order of the filter increases the no. of lobes in the frequency response increases.