all information about the GPS

1. GPS-PRINCIPLE AND
WORKING
Presented by;
Arnish Prajapati
Environmental Science
(Semester : II)

2. OUTLINES
• What is GPS ?
• Principle
•How GPS working?
1 Space segment
2 Control segment
3 User segment
•References

3. WHAT IS GPS?
• Global positioning system
• Space based satellite navigation system
• Provides location and time information in all weather
• Used to refer locations
• Secure cars, track your vehicles
• GPS system managed by the U.S Air Force for the
Department of Defence (DOD)

4. PRINCIPLE
• Geometric principle
• You can find one’s location if you know its distance from
other, already known locations
• Things which need to be determined
-Current locations of GPS satellites
-The distance between receiver's positions and the
GPS satellites

5. Distance measurements from two satellites limits our
locations to the inter section of two spheres, which is
a circle

6. A third measurement narrows our
location to just two points.

7. A fourth measurement determines
which point is our true location

8. HOW GPS WORKING??
• Components of GPS
• 3 segments:
Space segment
Control segment
User segment

9. SPACE SEGMENT
• GPS satellites fly in circular orbits at an altitude pf
20,200 km and with a period of 12 hours
• The orbital position is constantly monitored and updated
by the ground stations.
• Powered by solar cells
• Each satellites is identified by number and broadcasts a
unique signal
• Each satellite has 6 orbits
• 3 satellites works for GPS fourth satellite work for
accuracy.

10. CONTROL SEGMENT
• The control segment consist of 3 entities
1 Master control system
2 Monitor stations
3 Ground antennas

11. MASTER CONTROL SYSTEM
• Responsible for management of the remote monitoring
and transmission sites
• Check up is performed twice a day, by each of 6 stations
, as the satellites complete there journey around the
earth

12. MONITOR STATION
• Altitude , position , speed , and overall health of the
orbiting satellites check by monitor station.
• 16 monitoring stations located throughout the world
• 6 form the Air Force and 10 from the national Geospatial-
Intelligence Agency(NGA)

13. GROUND ANTENNAS
• Monitor and track the satellites from horizon to horizon
• Communicate with the GPS satellites for command and
control purpose.
• Transmit correction information to individual satellites.

14. USER SEGMENT
• Consists of the users and their GPS receivers
• Users are civilians and military
• Receivers come in verity of formats
• GPS receivers are composed of
1 an antenna ( turn to the frequencies transmitted by
the satellites)
2 receiver –processor
3 highly-stable clock (often a crystal oscillator)
• Also include a display for providing location and speed
information

16. REFERENCES
• Geoinformatics , A M Chandra ,2016
ISBN 978-81-224-3875-8
• http://www.circuitstoday.com (accessed on 18/02/2019
at 9 pm)

17. THANK YOU