GPS common terms

1. Coordinates A set of values ​​describing your location, generally latitude (north or south) and longitude (east or west). The UTM coordinate system measures your distance in meters from the equator (north or south) and the prime meridian (east or west). Another coordinate system MGPS (Military Grid Reference System) is also based on UTM, but the UTM coordinates are more finely divided, it is only used in military GPS receivers.

2. 2D and 3D coordinates Your plane positions, such as longitude and latitude, are called 2D coordinates. You need at least 3 GPS satellites to locate the 2D coordinates. If the satellites are blocked by trees, mountains or buildings, you may only get 2D coordinates.
Latitude, longitude and speed are called 3-dimensional coordinates, and it is determined that it requires at least 4 satellites. Almost all GPS receivers are based on providing 3D coordinates.

3. Roadside markers and waypoints You can store a location as a roadside marker or waypoint. It can be a location you locate on the way, or it can be a coordinate you entered or another location, such as a destination. The GPS device will give it a name, such as LMKOZ, you can also rename it with an easy-to-remember name.

4. Location When your receiver marks your coordinates based on the GPS satellite information, it will determine your location. Many GPS devices allow you to choose to mark or store your current location as a wayside mark or waypoint. Some even allow you to name the location or add an icon.

5. Route The route includes the starting location and destination, as well as the location of the route. Between two points on a route is called a flight segment. A route can consist of one or several flight segments. If you are hiking, you can enter a route, which includes directions, places to rest or camping, and your destination. There are some GPS devices that allow you to follow the route in reverse or set a reverse route.
The route has two main purposes:
1) If you are going to explore or travel, you can get the coordinates of the location from the highway map or some map software. This is very useful in future trips. Some GPS receivers allow you to design your trip line on a computer and then load it into your GPS receiver;
2) If you record the location you have traveled while traveling with a GPS receiver, you can copy or download your route and find out the location of the most valuable attractions, or the most suitable location for fishing, or you see The location of a rare bird, or the location of a cave where you are hiding in bad weather. If a player is injured, the rescue team can find the location of the injured according to the exact coordinates. Search and rescue personnel can download the complete route to know the location of the expedition.

6. Altitude If enough GPS satellites are visible, some GPS devices can provide altitude information (altitude). Due to the characteristics of the GPS system itself, the height is not as accurate as the plane coordinates.

7. Heading This reflects the direction of the GPS receiver moving in the horizontal direction, and does not require you to point the GPS receiver exactly in this direction. You can see this value when you move. The heading value is distributed clockwise from 0 to 359 degrees, which corresponds to the compass value.

8. Azimuth If you have selected a roadside sign or waypoint and want to know the direction from your current location to it, you need to know the value of the azimuth. It is a value distributed clockwise from the north. If the azimuth to your destination is 270 degrees and your moving direction is 240 degrees, your route will deviate from your destination by 30 degrees. If you are taking a train, this may not matter, but if the deviation is large, you need to check the map, maybe your route is wrong.