Global Positioning System or GPS was originally designed for positioning and navigation in the military area.Today it is used in the civilian sectors, devices. All of us today well aware that there hundreds of devices including the Android mobile Phones and Android Tablets where Global Positioning System is integrated.
Design and operation of Global Positioning System
Global Positioning System is based on satellites that broadcast radio signals encoded for their current position and the exact time. From the signal propagation time Global Positioning System receiver can calculate its own position and speed. Theoretically, signals from three satellites exact position and height can be determined. In practice, however, Global Positioning System receivers might not have a clock that is accurate enough to measure the times correctly.
Global Positioning System signals can, however, not only determine the position but also the velocity determine the recipient. This is generally done by measuring the Doppler effect or the numerical differentiation of the places. The direction of movement of the receiver can also be determined and as an artificial compass or serve for alignment of electronic cards. The compass feature is also based on the Doppler effect. This means that it is not at rest receiver is possible to perform an accurate compass reading. The Global Positioning System receiver works in motion, the compass does a short delay. Modern Global Positioning System use mainly magnetometer for compass reading.
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In order for proper functioning a Global Positioning System receiver always need at least four satellites to contact, among a total of at least 24 satellites orbiting the earth every sidereal orbit twice in an average orbital altitude from 20,200 km.
Global Positioning System in practice
The use of Global Positioning System devices has grown considerably in recent years by low-cost technology. Global Positioning System is used for trace and tracking for identification and storage of routes and their time as an electronic logbook. Localization of employees, products, or wards, sick and the elderly can be done by specific Global Positioning System receivers.
In future articles we will specifically discuss on specific Global Positioning System devices.
