Inverse of xcorr?

Hi all.

I have a signal that is a cross correlation between to signals:

X=xcorr(A,B)

But in my case I get X and I can compute B... any idea how to make the inverse of the cross correlation so that I get:

A=ixcorr(X,B)

[Jonas]

since convolution and cross correlation are very similar, you may have a look into deconvolution, also something in this thread

Answer 1

[vidyesh]

Hi Mariano,

Inverse of the cross-correlation can be calculated using the deconv function (as suggested by Jonas). Note that for two real signals 'x' and 'y', cross-correlation of 'x' and 'y' is equal to convolution of 'x' and 'y[-n]' (time reversal of y).

Therefore you can calculate 'x' using the below code.

x = randi([1,10],1,5);
y = randi([1,10],1,6);
R = xcorr(x,y);
x2 = (deconv(R,fliplr(y)));
disp(x)

     8     4    10     9     6

disp(x2);

    8.0000    4.0000   10.0000    9.0000    6.0000    0.0000

Hope this helps.