MATLAB CODE:

close all;clear all;clc; a=zeros(1,10);b=ones(1,10);x=[a a b b b b a a];%%%% rectangular pulse %%%%t1=-40:1:39;subplot(2,2,1);plot(t1,x);xlabel('Time');ylabel('Amplitude');title('Plot of rectangular pulse'); %%%% DFT of the above pulse %%%%f1=-pi:pi/128:(pi-pi/128);y=fftshift(fft(x,256));subplot(2,2,2);plot(f1,abs(y));xlabel('Frequency');ylabel('Amplitude');title('Plot of sinc pulse'); %%%% Phase versus frequency plot %%%%subplot(2,2,3);plot(f1,phase(y));xlabel('Frequency');ylabel('Phase');title('Phase versus frequency plot');