Super Bowl's super-stadium offers state-of-the-art wireless

by John Cox

January 22, 2008 —

This year's Super Bowl
stadium will welcome the Patriots, Giants and their fans with an advanced wireless
system. Actually, several of them.

Less than 18 months old, the University
of Phoenix Stadium in Glendale, Ariz., is home to the Arizona Cardinals
football team. But its 1.7 million square feet of space, looking
like a gigantic aluminum cheese Danish, hosts an array of other tenants
and visitors, from other bowl games like the Tostitos Fiesta Bowl, to the Rolling
Stones and the World of Wheels Autorama. To serve them, and up to 63,400 fans,
the stadium offers pervasive Wi-Fi, wall-to-wall support for five different
cellular carriers, and a separate, dedicated 450MHz public safety net.

Most of the wireless signals are being carried via a combination of single-mode
fiber and coaxial cable to and from ceiling-mounted antennas, all part of a
system
from MobileAccess of Vienna, Va. The company is one of several vendors of
so-called "in-building wireless" or "distributed antenna"
systems, which typically transport multiple kinds of wireless signals to distributed
antennas. The result enables pervasive high-quality cellular and Wi-Fi coverage,
and lets base stations and Wi-Fi access points be centralized in one or a few
locations.

Hartsfield-Jackson Atlanta International Airport, one of the busiest in the
nation, adopted
a similar approach, using products from LCG
Wireless.

Distributing wireless

MobileAccess
has several components in a central head-end, usually including base stations
from cellular operators, linked via fiber to remote hubs, where the Wi-Fi access
points are collected. The hubs link via coax cable to the 5-inch dome-shaped
distributed antennas. Among other things, the MobileAccess gear transports the
wireless signals, acts as repeaters and offers extensive network management
features.

The in-building wireless system was part of the original plan for the $450
million, multi-use
stadium, which boasts both a retractable roof and playing field, says Mark
Feller, vice president for technology, Arizona
Cardinals. The stadium does not have a traditional data center: Instead,
it has the MDF, or main data facility, which houses and connects the infrastructure
of all-Cisco routers and switches, and phone lines and other facilities. For
the Cardinals, this central room is a way station that links Cardinal voice
and data users in the stadium with the data center proper at the team's headquarters
several miles away in neighboring Phoenix.

Other stadium tenants, such as the Arizona Sports and Tourism Commission, the
concession service and a security company, use this flat IP net infrastructure
for voice and internet access.

An air-blown fiber LAN

The main network connections are created by an air-blown fiber LAN system called
FutureFlex,
from Sumitomo Electric Lightwave, in Research Triangle Park, N.C. Instead of
running fiber cable, the installers lay down tube cells, which Feller describes
as a kind of freeway with multiple, empty lanes. When capacity is needed, special
equipment uses compressed air or nitrogen to blow the optical medium through
these lanes. "We can blow additional fiber capacity in a matter of hours,
instead of days or weeks," he says.

The MobileAccess wireless system is layered over this infrastructure. "We
knew we would have [demand for] every type of wireless coverage," Feller
says. That includes Wi-Fi, a host of cellular services, and dedicated emergency
and first-responder nets, including conventional two-way radios. "Looking
at all these separately, we'd have to have repeaters and antennas all over the
place," Fellers says. "It would be cumbersome, unsightly, expensive
and inefficient."

After evaluating several candidates with the help of the network integrator
for the stadium project, Insight, and an in-building wireless integrator, Cellular
Specialties (CSI), MobileAccess got the nod. CSI handled the installation,
including extensive frequency testing throughout the huge facility, finally
placing 25 remote hubs to ensure optimal coverage for all the wireless signals.

The carrier base stations, from Alltel,
Cingular/AT&T,
Sprint/Nextel, T-Mobile
and Verizon, are located
in a common facility about a mile from the stadium, linked over fiber optic
cabling to the MobileAccess head-end. As each carrier was brought on line, the
entire system was extensively tested to ensure optimal coverage and signal strength,
says Feller.

Flexible Wi-Fi coverage, expansion

The Cisco Wi-Fi access points are collected in the various remote hubs, where
they're plugged into a Mobile Access aggregator. The number of access points
varies with the expected Wi-Fi demand in a given area. "For us, the majority
of Wi-Fi requests are in the press box during a football game," Feller
says.

When more Wi-Fi capacity is needed, additional access points are simply plugged
in. Temporary steel-frame and drywall booths and rooms are installed at the
top of the stadium, and these and some areas outside the stadium will also get
Wi-Fi connectivity. According to Feller, Wi-Fi use on the stadium floor and
in fan seating is increasing, as more handsets appear with both cellular and
Wi-Fi radios. (Learn more about Wireless LAN Management products in our Wireless
LAN Management Buyers Guide.

The public safety net is a separate infrastructure, with its own transmitters,
repeaters and other equipment, all fully controlled by the public safety agencies
that rely on them.

So far, there has been no interference from the broadcast television trucks,
with their massive microwave radios, which park along the south side of the
stadium during games. The only interference Feller expects will be the kind
on the playing field when the undefeated New
England Patriots meet the hard-charging New
York Giants on Feb. 3.

Network World