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December 5, 2006 4:00 AM PST
Turning cell phones into lifelines
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As has been reported in recent days, CNET Reviews editor James Kim and his family disappeared in Oregon during a Thanksgiving road trip. James' wife, Kati, and their two children, Penelope and Sabine, were found safe Monday afternoon. The body of James Kim, who left his family on Saturday in search of help, was found Wednesday.
Authorities conducting the search said at a news conference Monday that a signal sent from the Kims' mobile phone to a tower in the region was key to locating the family.
The search for the Kim family is the latest example of how important cell phone technology has become as a public safety tool.
While other technologies such as global positioning system, or GPS, navigation may help people find their way out of trouble, it does little to help when people are stranded on the side of the road like the Kims were. Tracking devices that send beacons to rescuers could be helpful, but they are used mostly by wilderness backpackers and backcountry skiers. Few people carry them on road trips. And even though satellite-based tracking technology exists, even fewer people are likely to consent to having their whereabouts tracked on a daily basis in the off chance that they might get lost on a backcountry road.
At the end of the day, the technology that has proved the most valuable for locating lost or missing people has been cellular phones.
"Navigation tools may help someone if they need to understand where they are to get to safety," said Kiyoshi Hamai, director of sales and product management with Mio Technology, a company that sells portable navigation devices using GPS technology. "But in order for someone to find you, you really need a device, like a cell phone, that can provide two-way communication."
Even General Motors' OnStar service, which provides GPS navigation and tracks cars when they are stolen, relies on a cellular network to communicate with the GPS receiver in the car.
"We don't communicate with our in-vehicle OnStar device via satellite," said Steve Davis, Service Line Manager for the OnStar Personal Communications service. "We connect to the device through a cellular phone connection. And if we can't connect to it through the cellular network, then we can't retrieve the GPS location information stored in the device."
Always connected
So how does it all work? Mobile devices, when they are within range, constantly let cell towers and the mobile switching center, which is connected to multiple towers, know of their location. The mobile switching center uses the location information to ensure that incoming calls and messages are routed to the tower nearest to the user.
If a subscriber is unable to get service, this location information is usually purged from the mobile switching center. But some location information may remain in call detail records. Some mobile operators may store the most recent communication between a device and a mobile switching center for a certain period of time, usually 24 hours.
When someone is missing, even this small bit of information can prove useful in determining the approximate location of a device using the updates from the mobile switching center. If the mobile subscriber is still within cell phone range, authorities can track his or her general movement by following the sequence of towers the phone has contacted or pinged. And if the cell phone goes out of range or runs out of battery power, the mobile operator may be able to use the last recorded location before the cell phone either lost its signal or lost power.
But the most useful information for locating people when they are lost comes when someone has initiated or received a call or text message on their phone. Mobile operators keep records of these events for billing purposes in what is known as a call data record, or CDR. And they can go back to these records to get a historical account of the cell phone's location.
This is actually what authorities used to locate the Kims' phone, according to Eric Anderson, director of engineering for Edge Wireless, a regional mobile operator that provides cellular phone service in the area where the Kims were stranded. One of Edge Wireless' cell phone towers briefly connected with one of the family's phones at about 1:30 a.m. November 26 near Glendale, Ore. The phone was connected long enough to the network to send a notice that there was a voice mail or text message waiting. But the connection didn't last long enough for the Kims to retrieve the message or initiate a call for help.
Still, the connection was long enough that two Edge Wireless engineers, Eric Fuqua and Noah Pugsley, were able to find this information in the CDR to determine that the family was in sector "Z" in the southwestern portion of the cell site's 26-mile radius. Wolf Peak's "Z" sector provides coverage to remote areas with little population and very little cell phone traffic. Using this information, authorities sent out rescue teams, which eventually located Kati Kim and her children.
Anderson said that the family was lucky that they were Cingular Wireless subscribers. Edge Wireless uses the same GSM network technology that provides roaming coverage to Cingular customers. If the Kims' phone had been with a different provider that didn't have roaming coverage with Edge Wireless, then the company might not have received any signal at all after they left the major highway, and the cell phone would have been of little use to authorities trying to rescue them.
"Where the Kims' car was found was on the fringe of our coverage area as it was," Anderson said. "So it was a miracle that the phone was able to lock onto the network at all."
Anderson said that if people ever find themselves in a similar situation--lost and having difficulty getting cell phone reception--they should search for the highest ground or area that may be in the line of sight to a tower. They should hold the phone away from their bodies or high so it has no obstructions to a possible tower. It may take up to two or three minutes for it to synchronize or connect with the cell tower and mobile switching center. Even if they can connect for a second or two, it could be long enough to register a voice mail or text message, which could ultimately help wireless engineers track their location.
Embedded GPS
The E911 FCC regulations are likely to help rescuers find those who are lost even more quickly, even if people are unable to reach a 911 operator for help.
Phones sold today by Edge Wireless and other carriers using GSM network technology, such as Cingular and T-Mobile, comply with the FCC regulations using network-based technology that calculates a mobile phone's location in real time using signal analysis and triangulation between towers. Wireless carriers using CDMA network technology, such as Alltel, Verizon Wireless and Sprint Nextel, have GPS technology embedded in them to fulfill the E911 government mandate.
Both network and GPS location information allow authorities to send signals or pings directly to these handsets to find an approximate location of the phone.
Some cell phone operators, such as Disney Mobile, Boost Wireless and Helio, are using GPS-enabled phones to provide tracking services. Disney Mobile targets parents wanting to keep tabs on their small children, while Boost and Helio are marketing their services to appeal to young people who are looking to keep in touch with their friends.
Services that allow people to be tracked either through the cellular phone network or by satellite introduce some obvious privacy concerns. But Joe Farren, director of public affairs for CTIA-The Wireless Association, a trade organization representing mobile operators, said that is why people must opt-in to services that allow tracking.
Still, cell phones have their limitations. For example, battery life varies greatly. Some batteries last for several days, while others may lose power after only a few hours.
And even though cellular network coverage has improved tremendously over the past several years, it is still not ubiquitous in the United States. Even some urban areas have dead zones, particularly in buildings or underground. Rural and remote areas suffer most from lack of coverage. And these areas also happen to be places where people are most often stranded or lost.
All that said, Farren believes that cell phones will continue to play an important role in providing safety and security for people.
"Wireless phones are an incredible safety tool," he said. "They are the most valuable tool invented for some time. They save scores of lives. And they will continue to get better."
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28 comments
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Several states have adopted a cost recovery attiude toward the location deployment. The state pays the cell company to install the equipment and technology for the service. That's OK if all it is for is emergency calling; but the provider gets to profit off its use for other services they charge for. And there is no payback to the government.
It is true the metro allure is still alive and well in both areas - cellular service and location availability. And, until there is some means to fund this where politicians do not rule by vote or special interest appeal, it will remain so.
Wonder how often a cellphone wakes up to scan for signal after the cellphone enters powerdown mode for lack of signal?
Now if we could only keep people from yacking on cell phones to distraction while they are doing the serious business of driving their cars, then I'll be 100% convinced that we're safer with cell phones.
I can see a time soon where the records of everyone who's been close to the scene of a murder will be subpoenaed to look for both the culprit and potential witnesses. And you can be sure that more than one murderer will be caught because their phone placed them at the scene at the right time.
www.wikiprotest.com
awareness to all that any one of us can get into trouble. We don't
have to go on an huge backcountry expedition, but a simple drive
through the mountains can be tragic. How many more of these go
un published? Hopefully this is a good lesson for all that we need
to be prepared. Day time signalling device (mirror and whistle) and
a night time signalling device (strobe light and whistle) should be
in every car at the bare minimum.
with a cell phone terminal to receive and send
calls to cell phones that are not within cell
tower range. It would certainly facilitate the
location of people that were lost or injured.
Comments?
SK
These kind of things in today's world should not exist but they do & will continue until the human race starts caring more about each other than just a "how much money can we make" attitude!
Money should not be everything!
As a long time resident of Oregon's coastal mountains, we know how unforgiving Oregon's ocean, mountains, weather can be; plus GPS and cell phones are useless in much of Oregon. They don't work when you're in a canyon, behind a mountain, in timber and not in line of site of or out of range of a cell tower.
Ironically, last week, the planning commission that I sit on ruled against a cell tower that would have filled in one of the many dark areas along the coast. Many opponents complained that it would be unsightly. We have this problem with every application.
So- I think technology needs to address this issue. I know we can conceal them as church steeples, pine trees etc., but this isn't really effective in the "wilderness."
Perhaps some sort of cheap micro-technology could be developed so that installations could be more ubiquitously placed along roadways.
Wake up America....or other off shore companies will place their towers in those remote areas and they'll build the road to the towers!!
On another note:
I am from the Grants Pass area and am very familiar with the Bear camp road on which the Kim's were found. My friend and I once helped rescue a family that was stuck in the snow on Bear camp road and know how treacherous the road can get.
My sympathies to the Kim Family.
I hope that we all learn a lesson from James' death: We are the ones responsible for our own safety. When traveling into remote areas we should all be aware of the perils that surround us and pack emergency gear such as matches, flashlights, flares,extra batteries and alternative emergency communications gear such as ELTs,CB radios or Ham gear if you are licensed. Let's not have more families suffer similar fates.
If you get lost, you turn on your GPS and it wills pickup your location and through an application such Verizon navigator it will guide you to safe area.
Another thing, some cell phone companies allow both options for their customers GSM and satellite, for example if you to Europe you can use your cell phone there because their system is GSM DRIVEN.
Giant step backwards in techonlogy.
which cell service the missing people are using and bring a
transportable cell tower to the general area they are located in?
This would give them an opportunity to get service where they are
and aid in their own rescue by connecting a phone call. I don't
think it's a very difficult procedure. It just takes a little cooperation
with the cell companies.
I cannot still get a cell phone signal (inexpensive 2-year old NET10 CDMA phone without GPS) from the nearest (US Cellular) tower 7 miles away =while I'm at home. That makes it useless for E911 (it's near useless for anything else - which is why I use Net10 - although I have upgraded from Tracfone). Since you can't triangulate with one tower, they could at best say they got a weak signal somewhere in a 6-7 mile radius (was I at the edge of the zone or inside a building/tunnel?).
Meanwhile, nearby EMS personal still bemoan the lack of E911 (In west central Illinois) due to political/cost concerns.
In the next county over, a rural cell company has filed to convert their GSM system over to CDMA, because even after intensive and expensive building campaign, they still cannot provide enough towers for decent coverage to all points. This is in flat, open farm country. No mountains or canyons here.
Meanwhile, some of the other predictions have come true. Warrant-less tracking of cell phones has been court approved in at least 3 state's federal courts. While millions of people and acres still lack any wireless service whatsoever, the broadband initiative has shifted over to flooding the concrete canyons that could be otherwise served.
Not to fear - I have a landline and a best of breed cordless phone (a 10 year old 900 MHZ DSS model) & can live with my best available - 1.5M DSL connection.