About GPS
The Global Positioning System (GPS) is a worldwide radio-navigation system formed from a constellation of
satellites and their ground stations. GPS uses these satellites as reference points to calculate positions accurate
within 10 meters.
Improving Radio Coverage
Wireless connectivity between radio-equipped portable terminals and host computers is unique and maintaining this
wireless connectivity over a wide area is fundamental to the usefulness of the network. As such, the scope and
reliability of radio coverage is a primary concern. Therefore, one of the most important features of the wireless
network is the degree of radio coverage provided. Coverage is influenced by terrain, buildings or a crowded room.
There are many things that can be done to improve coverage depending on location.
In any location
1. Performance can vary significantly at different times of the day.
2. Weather can affect performance.
On the street
1. Try all sides of a building to see which side provides the strongest radio signal.
2. Move from under trees. Pine needles absorb radio signals more than leaves.
3. Move away from overhead electrical wires.
4. Radio signals reflect off other buildings. Even in the signal shadow, the signal could be reflected back by
another building.
5. Try not to hold the unit. If possible, place it in vehicle, on a cabinet or desk.
6. If holding the unit, turn the unit in 90-degree increments to avoid shielding it with your body.
7. The signal is 1 - 2 feet across; therefore, moving several feet in any direction may give different results.
Inside a building
NOTE
GPS is not intended for use in buildings
1. Move toward windows.
2. Signals do not penetrate ground, therefore, there will probably be no signal in basements.
3. Reflective coatings on windows reflect radio signals. Try the side of the building that is least likely to have
coated windows.
4. Closed metal blinds can reflect radio signals.
5. Dropped ceilings sometimes hide an accumulation of electrical cable.
Electromagnetic Interference (EMI)
Page 24 of 57
Duo-Touch II Help
2/28/2008
file://C:\Documents and Settings\harwoodm\Local Settings\Temp\~hh5E31.htm
