What Is Gps - Navman iCN 630 User Manual

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WHAT IS GPS?

The Global Positioning System (GPS) is a network of satellites launched by the US military in
the 1970’s. The satellites continuously transmit accurate time and position information, which
is freely used by commercial and military applications worldwide. GPS receivers such as the
iCN 630 are designed to pick up the high frequency radio signals from these satellites, and use
the information to determine your exact location. Today, there are many applications that use
GPS, from marine to automotive, aviation and military.
There are 24 satellites in total, orbiting the earth at around 12,000 miles. While a GPS receiver
can detect signals from up to 12 satellites at any one time, only three are needed to provide the
two-dimensional position or “fix” (latitude and longitude) that is required for vehicle and marine
navigation systems. Aviation applications also need altitude and therefore need information
from at least four satellites.
The iCN 630 In-Car navigation unit is designed specifically to use GPS information to find
your current position, and to calculate the best route to your desired destination using the
road maps stored in its memory. The iCN 630 will then guide you with voice and visual
commands to your destination using the continuous stream of GPS data to track your
position as you take a trip.
NAVMAN iCN 630 user manual-ver 0.12
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