  Within the context of coded caching, the work reveals the interesting
connection between having multiple transmitters and having heterogeneity in the
cache sizes of the receivers. Our work effectively shows that having multiple
transmit antennas -- while providing full multiplexing gains -- can also
simultaneously completely remove the performance penalties that are typically
associated to cache-size unevenness. Focusing on the multiple-input
single-output Broadcast Channel, the work first identifies the performance
limits of the extreme case where cache-aided users coincide with users that do
not have caches, and then expands the analysis to the case where both user
groups are cache-aided but with heterogeneous cache-sizes. In the first case,
the main contribution is a new algorithm that employs perfect matchings on a
bipartite graph to offer full multiplexing as well as full coded-caching gains
to both cache-aided as well as cache-less users. An interesting conclusion is
that, starting from a single-stream centralized coded caching setting with
normalized cache size $\gamma$, then adding $L$ antennas allows for the
addition of {up to} approximately $L/\gamma$ extra cache-less users, at no
added delay costs. Similarly surprising is the finding that, {beginning} with a
single-antenna hybrid system (with both cache-less and cache-aided users), then
adding {$L-1$} antennas to the transmitter, as well as endowing the cache-less
users with a cumulative normalized cache size $\Gamma_2$, increases the Degrees
of Freedom by a \emph{multiplicative} factor of up to $\Gamma_{2}+L$.
