The document discusses the Global Positioning System (GPS). It provides a brief history of GPS, explaining that feasibility studies began in the 1960s, the Pentagon appropriated funding in 1973, and the first satellite was launched in 1978. It describes how GPS works using a network of orbiting satellites that send location data to GPS receivers on Earth to calculate position, speed and time. It also outlines the various segments that make up GPS including the space, control and user segments. Finally, it discusses applications and advantages such as navigation and working in all weather, as well as some disadvantages like limited indoor use.

1. GLOBAL POSITIONING SYSTEM (GPS)
Submitted To :
Ms. Anamika Srivastava
Submitted By :
A
Colloquium Presentation
RAJKIYA ENGINEERING COLLEGE , AMBEDKAR NAGAR
Under the supervision of
Mr. Ashish Kumar Srivastava
Deepti Pankaj
on

2. CONTENTS
 INTRODUCTION
 HISTORY
 WORKING
 APPLICATIONS
 ADVANTAGES
 DISADVANTAGES
 CONCLUSION
 BIBLIOGRAPHY
 VARIOUS SEGMENTS

3. INTRODUCTION
GPS is a network of orbiting satellites that send
precise details of their position in space back
to earth.
The signals are obtained by GPS receivers ,such
as navigation devices and are used to calculate
the exact position , speed and time at the
vehicles location.

4.  FEASIBILITY STUDIES BEGUN IN 1960’S.
PENTAGON APPROPRIATES FUNDING IN 1973.
FIRST SATELLITE LAUNCHED IN 1978.
SYSTEM DECLARED FULLY OPERATIONAL IN APRIL, 1995.
OPEN TO THE PUBLIC, 2000
The History of GPS

5. Humans
Have
always
been
Interested
in knowing
where
Things
Are…...

6. Where to go ?

7. How does GPS work?
 THE MORE SATELLITES THE GPS CAN “SEE”, THE MORE
ACCURATE IS YOUR READINGS.
 THE GPS MUST “SEE” THE SATELLITES, SO IT DOES NOT WORK
WELL IN THE DENSE FOREST, INSIDE CAVES, UNDERWATER, OR
INSIDE BUILDINGS.
 STATIONS ON EARTH, AND A GPS RECEIVER,
THE DISTANCES BETWEEN EACH OF THESE
POINTS CAN BE CALCULATED.
 THE DISTANCE CALCULATION BASED ON THE
AMOUNT OF TIME IT TAKES FOR A RADIO
SIGNAL TO TRAVEL BETWEEN THESE POINTS.
 USING SATELLITES IN THE SKY, GROUND
ALLOWS THE GPS RECEIVER TO KNOW WHERE
YOU ARE, IN TERMS OF LATITUDE AND
LONGITUDE, ON THE EARTH..

8. Segments
of GPS
 Control segment
 User segment
 Space segment

9. Space segment
 GPS satellites constellation composed of 24 operational
 These 24 satellites are placed in 6 circular orbits of equal
Satellites in space.
to 12hrs and these orbits are equally spaced with 60
degrees apart and at an inclination angle of 55 degrees
in equator.

10. Control segment
 The control segment comprises of 5 ground stations located on equator.
(4-monitor and 1-master station)
 Monitor stations measure the distances of the overhead satellites every
1.5 seconds and send the corrected data to master station.
 In master station the satellite orbit, clock performance and health of the
satellite are determined and determines whether repositioning is required.
 This information is sent back to the satellites using ground antennas.

11. USER SEGMENT
 The user segment consists of all earth –based GPS
 The user segment is totally user community , both
receivers.
civilian and military.

12. Applications
Location
Rescue
Marine
Tracking
Airways and
Military
Search and
Navigation

13. ADVANTAGES
 GPS works in all weather so you need not to worry of the climate as in other
navigating systems.
 GPS costs you very low.
 The most attractive feature of this system is its 100% coverage on the planet.
 It also helps you to search the nearby restaurants ,hotels and gas stations and is very
useful for a new place.
 GPS is extremely easy to navigate as it tells you to the direction for each
Turns you take to reach to your destination.

14. Disadvantages
 GPS satellites are weak ,so it doesn’t work as well indoor, underwater etc.
 The highest accuracy requires line-of-sight from the receiver to the satellite,
This is why GPS doesn’t work very well in an urban environment.
 If you are using GPS on a battery operated device, there may be a battery
Failure and you may need a external power supply which is not always possible.
 Sometimes the GPS signals are not accurate due to some obstacles to the signals.

15. CONCLUSION
 GPS is a network of satellites that continuously transmit coded information ,
Which makes it possible precisely identify locations on earth by measuring
distance from the satellites.
 GPS although was developed for military purposes, but the number of civilian
users of GPS already well far exceeds than number of potential military.
 As discussed in previous topic , its application fields vast and new applications will continue to be
created as the technology evolves.

16. BIBLIOGRAPHY
WebPages:
http://www.google.com
http://www.ALIGPS.com
http://trimble.com

17. THANK YOU

18. ANYQUERY