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, Sprint and Verizon each have cell phones available that use the Global Positioning System (GPS) to find a caller's location. While Cingular and T-Mobile 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.

This article was posted on October 29, 2005