  In this paper, we consider capacities of single-antenna terminals
communicating to large antenna arrays that are deployed on surfaces. That is,
the entire surface is used as an intelligent receiving antenna array. Under the
condition that the surface area is sufficiently large, the received signal
after matched-filtering (MF) can be well approximated by an intersymbol
interference (ISI) channel where channel taps are closely related to a sinc
function. Based on such an approximation, we have derived the capacities for
both one-dimensional (terminals on a line) and high dimensional (terminals on a
plane or in a cube) terminal-deployments. In particular, we analyze the
normalized capacity $\bar{\mathcal{C}}$, measured in nats/s/Hz/m$^2$, under the
constraint that the transmit power per m$^2$, $\bar{P}$, is fixed. We show that
when the user-density increases, the limit of $\bar{\mathcal{C}}$, achieved as
the wavelength $\lambda$ approaches 0, is $\bar{P}/(2N_0)$ nats/s/Hz/m$^2$,
where $N_0$ is the spatial power spectral density (PSD) of noise. In addition,
we also show that the number of signal dimensions is $2/\lambda$ per meter
deployed surface for the one-dimensional case, and $\pi/\lambda^2$ per m$^2$
deployed surface for two and three dimensional terminal-deployments.
