Navman iCN 620, Руководство пользователя

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8 NAVMAN iCN 620 user manual
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 620 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 620 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 620 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.
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