Sprint Nextel 595U - Manual (Page 96)

88 Section 3E: Frequently Asked Questions (Windows)
Location-Based Services limitations
To acquire a location fix, you must be connected to the Sprint network, (subject to
change) not roaming, and, for the initial fix, in 1X coverage.
If you're outside with a clear view of the sky, the USB modem uses MS-Based
position location technology. Weather conditions may affect your ability to get a
clear view of the satellites and thus to acquire a GPS fix. MS-Based GPS (Basic) is
for outdoor use only.
What GPS mode options are supported?
GPS on a Sprint data card works like any other GPS device. Sprint provides two
types of GPS mode: GPS Basic, and GPS Premium.
For more information, see “What is GPS Basic?” and “What is GPS Premium?” on
page 89.
What is GPS Basic?
Sprint GPS Basic supports GPS outdoors. Your USB modem requires an
unobstructed view of GPS satellites (in the sky), and, like any other GPS device,
might not perform well within forested areas or near tall buildings.
Sprint GPS Basic is based on GPSOne™ standards and uses Location-Based Services
for the first, fast, GPS fix. GPS coordinate values are made available to applications
via a local GPS NMEA Com port.
Note: Location-Based Services use Advanced Forward Link Trilateration (AFLT). AFLT is a type
of device-based position location technology. Unlike A-GPS, AFLT does not use GPS
satellites to determine location. Instead, the device takes measurements of signals
from nearby cellular base stations (towers) and reports the time/distance readings
back to the network; the readings are then used to triangulate an approximate
location of the device. In general, at least three surrounding base stations are
required to get an optimal position fix.
AFLT accuracy may vary, depending on the geometry of the cell towers in your
location.
Note: Sprint Location Services may not be supported if Network Mode is set to 1xEV-DO Only
or (subject to change) if you are roaming. To use Sprint Location Services, ensure
Network Mode is set to Automatic or 1XOnly , and ensure that you are in the network
coverage area (not roaming).