Cellular-Broadcast Service Convergence through Caching for CoMP Cloud RANs

Cellular and Broadcast services have been
traditionally treated independently due to the different
market requirements, thus resulting in different business
models and orthogonal frequency allocations. However,
with the advent of cheap memory and smart caching, this
traditional paradigm can converge into a single system
which can provide both services in an efficient manner.
This paper focuses on multimedia delivery through an integrated
network, including both a cellular (also known as
unicast or broadband) and a broadcast last mile operating
over shared spectrum. The subscribers of the network are
equipped with a cache which can effectively create zero
perceived latency for multimedia delivery, assuming that
the content has been proactively and intelligently cached.
The main objective of this work is to establish analytically
the optimal content popularity threshold, based on a
intuitive cost function. In other words, the aim is to derive
which content should be broadcasted and which content
should be unicasted. To facilitate this, Cooperative Multi-
Point (CoMP) joint processing algorithms are employed for
the uni and broad-cast PHY transmissions. To practically
implement this, the integrated network controller is assumed
to have access to traffic statistics in terms of content
popularity. Simulation results are provided to assess the
gain in terms of total spectral efficiency. A conventional
system, where the two networks operate independently, is
used as benchmark