36 I ICT TODAY
6 C-RAN
Centralized Radio Access Network (C-RAN) is essentially a
centralized network topology for wireless carrier baseband
units. These baseband units are the critical piece of the cellular
network that processes the RF signals and delivers them to the
transmitting radios (i.e., RRH or remote radio heads) and then to
and from mobile devices. Today, the typical configuration of a DAS
and associated carrier baseband/RRH units requires significant
space, power and capital to account for all the equipment. With
C-RAN, network operators can reduce operating costs, while also
reducing the capital spent on real estate leases by putting baseband
equipment in a centralized, off-premise space. Because only RRHs
are being installed in the served building, much less space is
needed by carriers in the head-end room.
CARRIER NETWORK
BASEBAND UNITS
(Offsite)
Fronthaul
Backhaul
RRH UNITS RRH UNITS
FIGURE 3: An example of a C-RAN architecture.
An additional benefit of C-RAN is that it gives the carriers the
ability to share their baseband units between multiple buildings
and to shift their network’s capacity to where it is needed. In the
future, OEMS will develop cloud-RAN solutions where virtualized
servers and software drive down further the overall cost and
complexity of in-building networks. C-RAN is an attractive solution
that will allow users to have increased wireless coverage and
capacity inside their building at lower overall costs.
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