  We consider the information content h of a scalar multiple-scattered, diffuse
wave field $\psi(\vec{r})$ and the information capacity C of a communication
channel that employs diffuse waves to transfer the information through a
disordered medium. Both h and C are shown to be directly related to the
mesoscopic correlations between the values of $\psi(\vec{r})$ at different
positions $\vec{r}$ in space, arising due to the coherent nature of the wave.
For the particular case of a communication channel between two identical linear
arrays of $n \gg 1$ equally-spaced transmitters/receivers (receiver spacing a),
we show that the average capacity $<C> \propto n$ and obtain explicit analytic
expressions for $<C>/n$ in the limit of $n \to \infty$ and $k \ell \to \infty$,
where $k= 2\pi/ \lambda$, $\lambda$ is the wavelength, and $\ell$ is the mean
free path. Modification of the above results in the case of finite but large n
and $k \ell$ is discussed as well.
