Plugging a Global Positioning System receiver alone into a wireless phone won’t solve the problem faced by 911 emergency operators receiving distress calls from cellular users.
“There’s no one solution,” said Bob Montgomery, network manager for the Cellular Telecommunications Industry Association.
“There are several location technologies that may be complimentary. Carriers are looking for the technology that suits their environment,” Montgomery said. GPS doesn’t work in buildings or in tunnels, but it may be the right solution for some terrain, he said.
A coalition of 911-emergency associations asked the wireless industry to create standards that would solve the problem of emergency calls coming from cellular users who don’t know their location. Landline, local phone networks are connected to the 911 emergency system in most U.S. metropolitan cities, so dispatchers immediately know the location of the phone being used in distress situations.
Not so with cellular phones. When wireless phones are turned on, they connect with the nearest cell site, which may not be in the county with the nearest emergency team, Montgomery said. Some callers know exactly where they are; some callers are lost or uncertain.
“The PSAP (Public Safety Answering Point) doesn’t know where you are and doesn’t know your phone number to call you back,” Montgomery said.
GPS in a phone could be of some help because it can provide specific location coordinates, but it is likely that several technologies will be used together to solve this problem. Other location technologies being considered include time difference of arrival and direction of signal.
“You build a standard and then apply technology to that. You have to look at the big picture every time,” Montgomery said.
