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"The Global Positioning System (GPS) is a space-based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. The system provides critical capabilities to military, civil and commercial users around the world. It is maintained by the United States government and is freely accessible to anyone with a GPS receiver." [Global Positioning System. Wikipedia]
This GPS operation diagram example was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Telecommunication Network Diagrams solution from the Computer and Networks area of ConceptDraw Solution Park.