Garmin Handheld GPS receivers take this information and use triangulation to calculate the user's exact location. The Garmin Handheld GPS receiver compares the time difference between when a signal was transmitted by a satellite with the time it was received. This time difference helps the Garmin Handheld GPS receiver to calculate how far away the satellite is. The Garmin Handheld GPS uses the same system to measure the distance from a few more satellites. With this data the receiver can determine the user's position and display it on the unit's electronic map.
A Garmin Handheld GPS receiver must be locked on to the signal of at least three satellites to calculate position on Earth and also to track movement. With the help of four or more satellites in view, the Garmin Handheld GPS receiver can determine the user's exact latitude, longitude and altitude. Once the user's position has been determined, the unit can calculate other information, such as speed, bearing, track, trip distance, distance to destination, sunrise and sunset time and more.
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