  In cloud radio access networks (C-RANs), the baseband processing of the
available macro- or pico/femto-base stations (BSs) is migrated to control
units, each of which manages a subset of BS antennas. The centralized
information processing at the control units enables effective interference
management. The main roadblock to the implementation of C-RANs hinges on the
effective integration of the radio units, i.e., the BSs, with the backhaul
network. This work first reviews in a unified way recent results on the
application of advanced multiterminal, as opposed to standard point-to-point,
backhaul compression techniques. The gains provided by multiterminal backhaul
compression are then confirmed via extensive simulations based on standard
cellular models. As an example, it is observed that multiterminal compression
strategies provide performance gains of more than 60% for both the uplink and
the downlink in terms of the cell-edge throughput.
