Will Your Cell Phone Reach 911 in an Emergency?
If you're one of the millions of cell phone users who count on
their wireless phone for emergency 911 calling........
You might want to think again.
Unfortunately, there's no guarantee that your 911 call will be
routed to an emergency call center. Much less, the emergency
dispatcher will have the ability to pinpoint the call's location.
Why?
Part of the problem is lack of service. Often, in more rural
areas, your cell phone has fewer towers available to receive
reception. And, many of those towers are designed for analog
calls - not digital.
But, since the FCC does not require it, fewer carriers offer
analog service -- or the ability to connect to it.
Not surprising, since much of the carriers' revenue is dependant
on features available only on digital networks.
Another problem?
There is no uniform Ehanced 911 system (E911) for wireless
carriers. The FCC neglected to force the carriers to conform
their E911 systems to a single technology.
Because of this, there are now two incompatable E911 systems in
the works.
Nextel
A>, Sprint
A> and Verizon
each have cell phones available that use the Global
Positioning System (GPS) to find a caller's location. While Cingul
ar and T-Mobi
le rely on a triangulation system.
Unfortunately, both E911 systems have their flaws. The GPS
system needs a minimum of three satalites to be able to "read"
the handset's location. Accuracy can be hampered by heavy
vegetation, mountains or tall buildings.
The triangulation system also has its shortcomings, because it
relies on the strength and timing of cell towers to determine a
location. It, too, requires multiple towers for accuracy. This
becomes more difficult in rural areas where towers are scarce.
To compound the problem, Emergency Call Centers are not equipt
with the technology needed to field E911 calls. Most smaller
centers lack the funding for the sophisticated equiptment, while
others lack the knowledge on how to integrate it to their
existing system.
According to a 2004 article in the San Diego Union Tribune, only
about 12% of the country's 911 centers had the ability to
pinpoint the location of wireless phone users emergency calls.
Which cell phone is best?
Dual band, or tri-band phones, allow both analog and
digital frequencies. If a 911 call does not connect in a digital
mode, the alternate analog network is available.
The FCC also requires that any carrier offering multi-frequency
phones must allow the 911 call to roam to another service, if
the call can not be completed on their own network.
Currently, only Cingular and Verizon offer dual or tri-bands for
both their service and handsets. Sprint PCS and T-Mobile
wireless phones operate on a digital band, but allow analog
roaming.
Nextel uses its own iDEN network, which has limited roaming
ability.