Circular Convolution Method 3

Matlab program to find Circular Convolution by using for loop function.

Two another methods of Circular Convolution:  Using fft and ifft predefined function and By matrix multiplication.

Matlab code

clc;

close all; clear all;

x=input('Enter the 1st sequence x[n] = '); 

h=input('Enter the 2nd sequence h[n] = ');

N1=length(x);

N2=length(h);

N=max(N1,N2); %Length of Circular convolved output sequence

if(N1>N2)

h=[h,zeros(1,N1-N2)]; %Modified second sequence if N1>N2

else

x=[x,zeros(1,N2-N1)]; %Modified first sequence if N1

end;

for n=1:N; y(n)=0;

for i=1:N; j=n-i+1; if(j<=0)

j=N+j;

end; y(n)=y(n)+x(i)*h(j);

end; end;

disp('Circular convolved output y[n ] =');y %To view output in command window

%To display and plot circular convolution

subplot(3,1,1);

stem(0:N-1,x);

xlabel('N-->');

ylabel('Amplitude-->'); title('1st input sequence x[n] ');

subplot(3,1,2);

stem(0:N-1,h);

xlabel('N-->');

ylabel('Amplitude-->'); title('2nd input sequence h[n]');

subplot(3,1,3);

stem(0:N-1,y);

xlabel('N-->');

ylabel('Amplitude-->');

title('Circular convolved output y[n]');

Command window

Enter the 1st sequence x[n] = [1 2 3 4]

Enter the 2nd sequence h[n] = [3 5 2 1]

Circular convolved output y[n ]  =

y =

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Figure window