CIRCULAR CONVOLUTION OF TWO SEQUENCES

clc;
close all;
clear all;
a1= input('1st Sequence x:');
b1= input('2nd Sequence h:');
ax=length(a1);
bx=length(b1);
n=max(ax,bx);
n3=ax-bx;
if(n3<=0)
a1=[a1,zeros(1,-n3)];
else
b1=[b1,zeros(1,n3)];
end
for r=1:n
y(r)=0;
for i=1:n
j=r-i+1
if j<=0
j=j+n;
end
y(r)=y(r)+b1(j)*a1(j);
end
end
subplot(3,1,1);
stem(a1);a1
xlabel('n');
ylabel('a(n)');
title('first sequence');
subplot(3,1,2);
stem(b1);b1
xlabel('n');
ylabel('b(n)');
title('second sequence');
subplot(3,1,3);
stem(y);
xlabel('n');
ylabel('y(n)');
title('circular convolution sequence');
disp('The resultant signal is:');y



Input:

1st Sequence x:[1 2 3 4]
2nd Sequence h:[1 2]

Output:

a1 =

1 2 3 4


b1 =

1 2 0 0

The resultant signal is:

y =

5 5 5 5