Page 55 - Introduction to Information Optics

40 1. Entropy Information and Optics

(a)

Fig. 1.14. Wigner distributions, (a) For a single tone signal, (b) For a pulse signal.

In other words, WDF does provide the frequency content of a time-varying
signal, instead of providing the time -frequency resolution as the ambiguity
function does.
In the following, we provide a couple of simple examples to illustrate of the
WDF. First, let us consider a single tone signal, as given by

i2nvot
u(t) = e .

By substitution into Eq. (1.127), we have

t v) v 0),

which is shown in Fig. 1.14a.