Laplace Transform
The Laplace Transform of any signal $ x(t) $ is....
$ X(s) =\int^{-\infty}_{\infty} x(t)e^{-st} dt $
The difference between Laplace Transforms(L.T.) and Fourier Transforms(F.T.) is that the F.T., X(w), of a signal, x(t), is simply the L.T., X(s), restricted to "s" being purely imaginary.