The Global Positioning System (GPS) is a satellite-based navigation system operated by the United States Space Force and owned by the United States government. It provides location and time information to GPS receivers anywhere on Earth and is freely accessible to anyone with a GPS receiver.
The United States government provides GPS as a service and has absolute control over the full constellation of 24 satellites and its availability to civilian and military users across the globe. As a result, many countries have developed or are in the process of setting up their own global or regional satellite navigation systems like the Russian Global Navigation Satellite System (GLONASS), China’s BeiDou Navigation Satellite System, European Union’s Galileo positioning system, and India’s NavIC.
GPS system consists of three segments. They are the space segment, control segment, and user segment.
- There are 34 satellites currently orbiting at an altitude of approximately 20,200 km (12,600 mi) that make up the space segment.
- The control segment is made of control stations and ground antennas for tracking and managing these satellites.
- The user segment is GPS receivers which include devices like smartphones, smart watches, GPS tracking devices, IoT Devices, etc.
How GPS works
GPS satellites transmit radio signals containing the current time and position data which are received by the GPS receivers, the time difference between when the satellite transmitted the signal and the receiver received it is proportional to the distance from the satellite to the receiver. A GPS receiver can monitor multiple satellites and calculate the precise position of the receiver. A minimum of four satellites must be in view of the receiver to compute and acquire position coordinates.
GPS has become a widely used tool for commerce, scientific uses, tracking, surveillance, and navigation. One of the key features of a modern smartphone is the in-built GPS receiver that determines your location and assists you in your day-to-day navigational needs.
Uses of GPS
Autonomous vehicle: GPS receivers are used in autonomous vehicles to guide them without human intervention.
Emergency services: GPS location is used for disaster relief and emergency services.
Fleet tracking: Fleet of vehicles tracked in real-time using GPS trackers to optimize business efficiency.
Geo-fencing: Vehicle tracking systems, pet tracking systems, and person tracking systems use GPS trackers attached to or carried by them to provide continuous tracking and alert notifications if the tracked subject leaves a defined area (Geo-fence)
Navigation: Navigational devices such as smartphones and smartwatches use GPS receivers to identify locations and provide directions and route information.
Target Tracking: Latest weapon systems use GPS to identify targets on the ground and air.
Navigation: Marines and soldiers use GPS to find targets and also to plan troop and supply movements.
GPS tracking devices
Many GPS receivers also transmit position data to a server or other interfaces using standard NMEA or proprietary protocols. One functional example would be a GPS Vehicle Tracking Solution, GPS trackers are installed in vehicles to track their location and monitor additional information related to the vehicle. These GPS Vehicle trackers can also interface with other vehicle sensors, cameras, or devices using serial connections, Bluetooth, and USB.