Global Positioning System (GPS)
Global Positioning System, or GPS for short, is a satellite-guided and global navigation system from the USA. It allows any user (private or commercial) to determine their own position and time using appropriate devices (smartphone, navigation device or (real-time) kinematics).
The Global Positioning System (GPS) is based on the constellation of the satellite system itself. The navigation system, also known as Navstar, relies on a total of 24 satellites, which are designed exclusively for time and positioning. These satellites orbit the earth in different orbits. The distance to the earth and the satellites to each other serves as the basis for determining the position. For a so-called high-precision measurement, at least three, in the best case four satellites are required. And depending on the application and device, the measurement result can now achieve an accuracy of up to one millimeter.
The global positioning system at a glance
- 24 satellites, at least three satellites are required to determine the position
- GPS can be used regardless of the weather
- GPS is independent of the time of day
- A measurement can be carried out by just one person with a GPS receiver
- The device determines the accuracy
However, the required accuracy depends on the degree of application. For example, devices in the private segment can be up to ten meters inaccurate. For comparison: in land surveying, the permitted tolerance is only up to three millimeters. Kinematic measurement technology is generally used here, in which a reference to a permanently installed reference station is established. The reason for the high accuracy is the reference, which not only calculates the position, but also outputs the corrected coordinates (earth curvature).
However, five to ten meters accuracy is sufficient for logistics. The GPS module is often combined with an RFID chip, which in turn leads to increased information density. If both are attached to the freight, it is possible to actively and seamlessly monitor the temperature and locate the transported pharmaceutical products in complex pharmaceutical logistics, for example.
Further information on the use of GPS in logistics can be found under Transport Management Systems.
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