  Caching multimedia contents at the network edge is a key solution to
decongest the amount of traffic in the backhaul link. In this paper, we extend
and analyze the coded caching technique [1] in an unexplored scenario, i.e. at
the edge of two-tier heterogeneous networks with an arbitrary number of users.
We characterize the performance of such scheme by deriving a closed-form
expression of the average backhaul load and reveal a significant gain compared
to other benchmark caching schemes proposed in the literature.
