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Distributed
Antenna System
Distributed antenna systems (DAS)
are commonly deployed at very large
venues – such as high rises, stadiums
and airports – at a much higher cost
than what venues under 200,000 sq.
ft. usually can afford.
A typical DAS system requires a sub-
stantial upfront investment in hardware,
cables, antennas and installation. Histori-
cally, large-scale DAS systems that cover
hundreds of thousands of square feet will
be in the $2 per square foot range. If the
space to cover is below 200,000 sq. ft.,
the cost per square foot can be $5 or even
$10, deterring most middleprise venues.
Hybrid In-Building
Cellular
New hybrid solutions are emerg-
ing to service the mid-sized enterprise.
These in-building, multi-carrier enter-
prise cellular systems provide the RF
distribution techniques of an intelligent
active DAS but with easy installation
and at a price point that can fit most
mid-sized enterprise budgets.
The hybrid active DAS for smaller
spaces can be installed off-air, with or
without an external antenna depending
on the available indoor signal strength.
Remote radio units connected by Cat
5 cable to the hub of the system are
placed throughout the building, utiliz-
ing Power over Ethernet so they can
be easily plugged in wherever needed.
This system can generally cover up
to 50,000 sq. ft.
In a densely populated venue with
extensive cellular use, or one larger than
50,000 sq. ft., a small cell/DAS hybrid is
a new solution now available. This small
cell/active DAS hybrid creates what is
termed a Supercell (i.e. a large single cell
versus multiple small cells) that provides
uniform access to the capacity introduced
by the small cell. Supercells are inher-
ently uncomplicated from a planning and
deployment point of view, and are far more
resilient to the potential of interference or
performance degradation considerations.
A small cell is generally centrally
located on premises and connected to
an intelligent DAS hybrid designed spe-
cifically for smaller spaces, with remote
radio units that can be readily placed in
the very best locations for the building
construction, and ultimately for cellular
use. By connecting a small cell to an
active DAS hybrid, users can achieve
uniform coverage and capacity distribu-
tion for venues up to 200,000 sq. ft. at
a far lower price point than a traditional
DAS, while eliminating potential inter-
ference and macro network dominance.
Most carriers already offer a small cell
that can be used in a Supercell. Some
carriers even provide a quick online order
form and next-day delivery. A typical use
case would be a medium-sized enter-
prise in a three-story, 20,000 sq. ft. space
with 50 or so employees where network
coverage is poor. A Supercell may be
expanded for larger spaces where the
density of users is unusually high, such
as a call center, and may be installed in
configurations that improve cellular ac-
cess for multiple carriers.
Overall advantages of the hybrid
approach include lower cost per sq.
ft., scalability and an unconditionally
network safe option for voice and data
(i.e. no risk of interference with other
systems or networks). The systems are
also self-configuring and self-optimizing,
which takes the guesswork out of de-
ployment in delivering optimal coverage.
Some systems can be managed
remotely, via a cloud platform. A variety
of basic or sophisticated reporting tools
give the system administrator or inte-
grator confidence that things are work-
ing as designed.
This latest hybrid approach is play-
ing a key role in bridging the technology
gap between the small and large-scale
enterprise spaces, providing integrators
with a solution that can be offered to
middleprise customers at a price they
are willing to pay to resolve their cellu-
lar connectivity challenges.
o
Joe Schmelzer is senior director at
Nextivity and a 20-year veteran of the
wireless industry. He has played a criti-
cal role in developing devices for chip-
set vendors, device OEMs and service
providers, including products for Sony,
Qualcomm, Google, Verizon Wireless,
AT&T, Dell and HP.
An Active DAS Hybrid
is a new solution for poor
cellular coverage in mid-sized
enterprise spaces. It can be installed
off-air for spaces under 50,000 sq. ft.,
or tethered to a small cell when more signal
capacity is required for higher density usage up
to 200,000 sq. ft., creating a Supercell.
Mobile & Wireless
Channel
Vision
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March - April, 2017
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