It very essential to have a logical understanding of what is GPS hiking and how they work before you choose an appropriate GPS for your hiking needs. You should be acquainted with the different elements of it. There is the GPS receiver/ antenna which is a very important element and there is also a part of the system which uses the received information to approximate where the device is positioned on an internal map.
The main principle of GPS hiking is actually very easy to understand because it generates similar results to conventional “triangulation” even though this GPS does not really use angles. If you need to find yourself on a map, then you need to find at least three points that you identify in the real world, which will then allow you to identify your location on the map. You can then gauge – using a compass – the azimuth that would needed to take you from the point on the map to your current position. Then, a line is drawn from all of the three points and where would the three lines meet is where you are on the map.
Converting this into the GPS world, you can then change the identified points with satellites and the azimuth with time taken for a signal to pass through every identified point to the GPS receiver. This will allow the system to work out approximately where it is situated, where in the circles are representing the distance from the satellite – calculated on the beginning of the travel time of the signal – intersect. Obviously, this means that the GPS locator must have the same coordinated time as the satellites – which, by the way, have atomic clocks on board. It simply cross checks the intersection of the three circles with a fourth circle which can be acquired from another satellite.
Actually, there are several difficult calculations taking place which allow the system to balance for atmospheric distortion of the signals but the principle remains the same.