1. Global Positioning System Presented by: Prateek Rastogi (05IT6013)

2. What is GPS?  Global Positioning System.  System to Identify the Position on Globe.  Network Of Satellites.

3. Segments Of GPS  The Space Segment  The Control Segment  The User Segment

4. The Space Segment  Consists of 24 satellites in 6 orbits.  Each satellites transmits low powered radio signals.  GPS Satellite  Name : NAVSTAR  Altitude : 11,000 miles  Inclination : 55 Deg to the Equator  Weight : 863 Kg(in orbit)  Orbital Period :12 hrs

5. The Control Segment  A Master Control Station  Unmanned Monitor Stations  Large Ground-antenna Stations

6. The User Segment  Users-Military and Civilians  GPS Receivers  Decodes the signals from Satellites.  Calculate the distance.

7. Modes of Operation  Standard Positioning System  Data Transmitted on L1 Frequency  For civil users  Accuracy is degraded  Precise Positioning System  Data Transmitted on L1 and L2 Frequencies  For Military users  Highly Accurate HA=100m VA=156m TA=340ns HA=22m VA=27.7m TA=200ns

8. Signals from GPS  Coarse/Acquisition- To determine Pseudo range  1023 bit long  1.023Mega-bits per sec  P Code  2.3547*10^14 bit long  10.23 Mega-bits per sec  Navigation Massage

9. Working Of GPS

10. How User Segment calculates the position?

11. Calculation of Position  Satellites Location  Almanac data  Ephemeris  Time is the essence  Velocity * Time=distance

12. Determination of Position Trilateration

13. Sources of Errors  Ionosphere Delays  Troposphere Delays  Clock Error  Multi-path Error  Relativity Error

14. Correction of Errors  Error Modeling  Mathematical Model  Data Frequency Measurement  Compare the Delays of L1 and L2

15. Applications  Industry  Agriculture  Mapping & GIS Data Collection  Public safety  Surveying  Telecommunication

16. Application Contd…..  Military  Intelligence & Target Location  Navigation  Weapon Aiming &Guidance  Transportation  Aviation  Fleet Tracking  Marine

17. Application Contd…  Science  Archaeology  Atmospheric Science  Environmental  Geology & Geophysics  Oceanography  Wildlife

18. References  www.trimble.com www.trimble.com  GPS primer “A Student Guide”(Aerospace Corporation)  An Introduction – Global Positioning system S. K. Upadhyaya, G. S. Pettygrove, J.W. Oliveira, B. R. Jahn1  GPS Guide for Beginners(GARMIN Corporation)