MATLAB program to perform linear convolution using circular convolution

Program code

%linear convolution using circular convolution

clc;

clear all;

close all;

x=input('Please enter the first sequence x[n] = ');

h=input('Please enter the second sequence h[n] = ');

len_x=length(x);

len_h=length(h);

h=[h zeros(1,len_x-1)];

x=[x zeros(1,len_h-1)];

L=len_x+len_h-1;

for i=0:L-1

    for j=1:L-i;

        a(j+i,i+1)=x(j);

    end

end

for m=1:L-1

    for n=m+1:L

        a(m,n)=x(L-n+m+1);

    end

end

b=transpose(h);

y=a*b;

y=transpose(y);

subplot(311);

stem(x);

disp('The sequence obtained after linear convolution of x[n] with h[n], is given below. ');

disp(y);

grid on;

title('First sequence x[n] ');

subplot(312);

stem(h);

grid on;

title('Second sequence h[n] ');

subplot(313);

stem(y);

Example of output

Please enter the first sequence x[n] = [1 2 3 4 5 6]

Please enter the second sequence h[n] = [1 2 3 4 5 6]

The sequence obtained after linear convolution of x[n] with h[n], is given below.

     1     4    10    20    35    56    70    76    73    60    36

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