How does the map software collect geographic information?

Now most of the satellite maps are the global positioning system (GPS) of the United States. Simply put, this is a satellite system consisting of 24 satellites covering the whole world. This system can ensure that four satellites can be observed at any point on the earth at any time, thus ensuring that satellites can collect the latitude, longitude and height of observation points, thus realizing the functions of navigation, positioning and timing. This technology can be used to guide planes, ships, vehicles and individuals to reach their destinations safely and accurately along selected routes.

Global Positioning System (GPS) is a new generation of space satellite navigation and positioning system jointly developed by the United States Army, Navy and Air Force in 1970s. Its main purpose is to provide real-time, all-weather and global navigation services for land, sea and air for intelligence gathering and nuclear explosion monitoring.

Some military applications, such as surveillance and emergency communication, are an important part of America's strategy of dominating the world. After more than 20 years of research and experiments, it cost 30 billion dollars. By March 1994, 24 GPS satellite constellations with global coverage of 98% had been deployed.

The GPS global positioning system consists of three parts: the space part-GPS constellation; Ground control part-ground monitoring system; User equipment part -GPS signal receiver.

GPS positioning technology has the advantages of high precision, high efficiency and low cost, which makes it widely used in strengthening and establishing various geodetic control networks, as well as highway engineering survey and deformation measurement of large structures.