Wireless
University brings cellular indoors
Coverage solution delivers wireless
inside its facilities and will scale easily.
by Michael Schoolnik
Operations manager Wally Hedman knew
from previous experience with wireless
systems that coverage inside the
university’s buildings would be a problem.
Cellular phones are the primary means of
communication for college students, faculty
and staff. Management at Ave Maria
University in southwest Florida knew that
ensuring proper reception for personal cell
phones, as well as university-issued
BlackBerry devices used by administrators
for e-mail, calendaring and voice calls,
would be important. Unfortunately, the
nearest cell tower was two miles away, so
even outdoor wireless reception was spotty.
According to university operations
manager Wally Hedman, the coverage problem
cropped up as soon as construction began on
the campus.
"We were putting in the underground
utilities," says Hedman. "I’d be on the cell
phone standing at ground level, and by the
time I got a few feet down into a trench,
I’d lose my connection."
Hedman knew from previous experience with
wireless systems that coverage inside
university buildings would be even worse, or
nonexistent. The first buildings finished
were the library, which housed the
administrative and faculty offices, data
center and library; an academic center; and
three student dormitories. These were all
constructed to withstand a hurricane, with
walls that are almost two feet thick in some
cases.
Since the campus enrollment was
relatively small at the time, none of the
major cellular carriers in the area was
interested in paying for a solution at the
site. As the library building neared
completion, Hedman purchased a passive
in-building cellular distributed antenna
system (DAS) for deployment there.
The crews deployed an antenna on the
building’s roof and fed the signal to a
bidirectional amplifier and the system’s
master unit, which were installed in the
school data center. From this master unit,
the signals were carried over runs of
half-inch LNR coaxial cabling to remote
antennas.
The results, however, were not nearly
good enough. "We wanted mostly to provide
coverage for the public areas in the
library, but if you moved one wall away,
into an office for example, the system made
no difference," says Hedman. "At the end of
a 100-foot cable run, the signal loss
between the antenna and the master unit was
so great that there was no noticeable
improvement in cell reception, unless you
were standing directly under the antenna."
With 1,000 acres of land on campus, the
university plans to add new facilities over
the next 20 years. In fact, the university
has completed its fourth dormitory (a 44,500
square-foot facility) and has already broken
ground on a 120,000-square-foot dormitory
that is scheduled for completion in July.
"We needed a system that could expand along
with our campus," says Hedman.
Wireless a safety issue
"We
considered
it an
essential
safety
issue," he
adds. "We
had
established
a university
requirement
that every
dormitory
needed to
have
cellular
service, and
we needed
cellular
service
inside the
library
building for
administrative
and faculty
communications.
We wanted to
be able to
reach anyone
on campus
via cell
phone in
case of an
emergency."
Hedman wanted an active system, in which
the cellular signal was regenerated as it
was distributed, and he eventually selected
the InterReach Fusion system from ADC. The
InterReach Fusion system delivers consistent
signal strength to every remote antenna
through a system of active hubs and remote
antenna units (RAUs).
"The Fusion system operated just like a
switch, where the signal was converted from
RF to intermediate frequency (IF) and back
to RF, with the signal regenerated each
time," says Hedman. "That architecture gave
us high signal output at every antenna no
matter how far it was from the signal
source. After that, it was only a matter of
deploying the antennas in a logical manner."
To cover the three-story library,
Hedman’s team deployed an InterReach Fusion
main hub in the data center, and then placed
two RAUs on each of the first two floors,
and one RAU in the center of the third
floor.
"Even though the building floors are
concrete," says Hedman, "we had plenty of
signal penetration to cover the whole
space."
The installed system supports 850-MHz and
1,900-MHz frequencies for Alltel, Sprint
Nextel, T-Mobile and Verizon users.
Once the library was covered, Hedman set
his sights on each of the 40,000 square-foot
dormitories. One of the advantages to the
Fusion system is that it can extend signals
over singlemode or multimode fiber, and the
university had laid singlemode fiber to all
building sites when the other utilities were
installed.
Since each main hub supports four
expansion hubs, Hedman was able to cover all
three of the dormitories by linking
expansion hubs to the main hub via fiber.
His team added an expansion hub in a wiring
closet on the main floor of each dormitory,
and then fed signals from each expansion hub
to the RAUs using standard CATV cabling.
"For the most recent dormitory, we just
added a new main hub and expansion hub to
the existing DAS and the whole system was
expanded," he says.
Another advantage of the Fusion system’s
architecture is its centralized management
and monitoring. Hedman monitors the entire
system from the data center. He also
monitors electricity levels.
"Florida is the lightning capital of the
world," he says, "but I can monitor all my
incoming voltages from the utility. We
probably took 25 lightning hits that
affected our buildings last year, but all
the buildings are on emergency generators,
and we have UPS backups on the critical
equipment, including the main hubs and the
expansion hubs."
Problem remedied
With the management and monitoring
system, Hedman was able to spot and remedy
the only fault in the system since it was
deployed. "The installers used push-on coax
connectors on the expansion hubs, and they
should have used crimp-on connectors," he
says. "We had a couple of the connectors
pull loose at one point, so then we went
around and replaced them all with crimp-ons
and we haven’t had any other problems since
then."
The cost to cover five buildings was
about $50,000, he says. Typical costs for
deploying the InterReach Fusion system run
10 cents to 50 cents per square foot of
coverage.
"Cellular coverage is one of those things
that everyone takes for granted," Hedman
says. "They don’t necessarily cheer when
they have it, but they sure complain when
they don’t. It’s hard to put an ROI on
enabling people to communicate and allowing
students to call their parents, or allowing
our emergency services people to broadcast
text messages about tornado alerts or other
events."
The university has new students register
their cell phone numbers as part of the
admissions process when they arrive on
campus so they can be made part of the
emergency communications system. With the
emergency system–used primarily for weather
warnings during hurricane season–the school
can simulcast text messages to all user cell
phones at the push of a button.
With a fully scalable and centrally
managed cellular system that guarantees
coverage, the university has made cellular
DAS deployments an integral part of its
expansion plans. The university plans to
build a new performing arts pavilion and a
law school building. These and other new
structures will receive DAS systems during
construction, and they will also be fed off
of Fusion main hubs in the data center.
MMichael Schoolnik is a freelance
writer based in San Francisco. Photo by J.
Mark Strong Photography.
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