Subject: [NEXTEL-1] GPS Users Still Lost in the Woods

From: [email-masked]
Date: Sun, 05 Oct 2003 03:22:03 -0400

GPS Users Still Lost in the Woods

By James Bernard Frost

The theory behind global positioning system devices is compelling: Since the
devices can tell their position in longitude and latitude to within 20 feet,
users can never be lost. In reality, though, GPS users are finding
themselves ... lost.

Search and rescue volunteers base this conclusion on anecdotal evidence. But
it seems GPS technology is making many hikers and backpackers feel
overconfident in their backwoods skills.

"I've heard stories of people being lost in the woods with thousand-dollar
GPS devices," says volunteer Shawn Gillogly. The biggest problem with GPS
"is that it assumes you know how to use it. Nothing can replace proper
orienteering skills and training."
Sales of GPS devices have grown exponentially in recent months. Popular
gadgets such as Garmin's eTrex were the craze in camping supply stores this
summer, and navigational systems that use GPS are showing up in many
high-end car models.

Still, even as the technology becomes more popular, consumers remain unaware
of its limitations. Although the service is theoretically available almost
worldwide, it may not work near high cliff walls or dense trees. It also
demands some understanding of orientation.

A smart backpacker will always carry "a detailed topographical map and a
compass, and not the battery-operated kind," Gillogly said.

The backcountry isn't the only place where GPS users are finding themselves
lost. Buildings, underpasses and tunnels also confuse or stop GPS devices.

"I knew (the system) was off when it showed us driving into the Pacific
Ocean," said Dan Faust, who used a navigation system in a Ford Taurus rental
car.

Some GPS enthusiasts have discussed replacing physical addresses with GPS
coordinates, especially in cities like Tokyo, which doesn't have a regular
numbering system for buildings and homes. But don't expect GPS to solve city
navigation problems in the near future.

The satellites themselves are aging and they have limits. The lack of
frequency diversity in the current GPS satellites contributes to
interference in urban settings, just to add to blockage from buildings.

As reported by Scientific American (http://tinyurl.com/lgpu), the U.S. Air
Force is considering a new global positioning system, which would resolve
these problems. But the earliest the military could launch next-generation
GPS satellites would be 2010.

Ownership is another issue that complicates GPS effectiveness. The U.S.
government owns the GPS satellites, and it can do with them what it pleases.
President Bill Clinton decreed an end to the degradation of the accuracy of
civil GPS frequencies in 2000, but it is not a stretch to think that
national security issues could bring back civilian restrictions.

Europe and China are working on a rival system called Galileo
(http://europa.eu.int/comm/dgs/energy_transport/galileo/index_en.htm, but
that project is still in development and faces political pitfalls.

http://www.wired.com/news/print/0,1294,60379,00.html

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