I am trying to understand how exactly to implement what is known as a 'pre-whitening' filter or simply a 'whitening' filter.
I understand that the purpose is to make it have a delta as its autocorrelation function, but I am not sure how to do this exactly.
The context here is the following: A signal is received at two different receivers, and their cross-correlation is computed. The cross-correlation can look like a triangle, or some other godforsaken shape. Due to this, it becomes hard to find the peak of the cross-correlation signal. In this case I hear about having to 'whiten' the signals before a cross correlation is performed on them, such that the cross-correlation is now more delta-like.
How is this done?