GPS-1 (1).ppt
- 1. Global Positioning System by B. Ram Chander
- 2. Objective • By the end of lecture, the trainee will be able to describe History, Main Componets of GPS and How it works (Basic concepts).
- 3. Where we can Use GPS?
- 4. What is GPS? GPS, which stands for Global Positioning System, is the only system today able to show you your exact position on the Earth anytime, in any weather, anywhere.
- 5. History of GPS • US Department of Defense started GPS Project in 1973 and called it NAVSTAR (Navigation Satellite Timing and Ranging System) • The first prototype spacecraft was launched in 1978 • Exclusively for defense and military purposes • Civilian use- partially allowed in 1980 • Full 24 satellites launched by 1995 • In 2000, GPS was made fully public use
- 6. Main Components of GPS System • Space Segment • Control Segment • User Segment
- 7. Space Segement (Satellites) • 31 satellites • 27 satellites are used at a time • 24 satellites are mandatory and 3 satellites are used as Mandatory. • These 24 satellites orbit the earth in their orbits twice a day • On an average 9 satellites are visible at any time which certainly improves the reliability and accuracy. • Satellites emits signals with multiple atomic clocks • Life span- 10 years
- 8. Control Segment (Ground Station) • 1 Master Control station. • 1 alternate master control station • 11 command control antennas • 16 monitoritng sites
- 9. Monitoring Stations • Track GPS satellites as they pass overhead • Collect navigation signals, range/carrier measurements, and atmospheric data • Feed observations to the master control station
- 10. Master Control Station • Provides command and control of the GPS constellation • Uses global monitor station data to compute the precise locations of the satellites • Generates navigation messages for upload to the satellites • Monitors satellite broadcasts and system integrity to ensure constellation health and accuracy • Backed up by a fully operational alternate master control station
- 11. Ground Antennas • Send commands, navigation data uploads, and processor program loads to the satellites • 4 dedicated GPS ground antennas plus 7 Air Force Satellite Control Network (AFSCN) remote tracking stations
- 12. User Segment (GPS Receiver) GPS-receivers located in • cars, vehicles • planes • Mobile phones, Watches etc Receiver uses the Satellitte transmitted data to estimate the precise location of the user
- 13. How GPS Works? • The satellites use ultra-precise atomic clocks • Satellite transmits radio signals at regular intervals about its location and time • Receiver monitor information from multiple satellites (Min. 4) to calculate and identify precise location with Trilateration method. https://www.youtube.com/watch?v=A iSuXDWbqs0 • To know more about Trilateration vist https://www.youtube.com/watch?v=4O3ZVHVF hes • Full information visit https://www.gps.gov/
- 14. Summary • What is GPS? • History of GPS • Main components of GPS • How it works?
- 15. Any Questions?
- 16. THANK YOU