GPS-in Nutshell

2. What’s it?
• It is a Space based satellite
navigation system.
• Provides : location and time
information in all weather
conditions.
• Maintained by the United
States government
• Accessible to anyone with a GPS
Receiver.

3. History:
• On June 26, 1993, the U.S. Air Force launched
the 24th NAVSTAR Satellite into orbit.
• The network of 24 satellites known as GPS.
• Roger L . Easton is widely credited as the
primary inventor of GPS.
• It became fully operational in 1994.

4. Types of GPS:
• They vary according to our need.
Major types:
• GPS Navigators
• Hand-held GPS
• GPS Trackers
• Emergency GPS

5.  It consist of three segments.
 Space Segment
 Control Segment
 User Segment
 Calculate :
 three-dimensional Location
 the current time.

6. Segment description:
• Space segment:
Composed of satellites.
Constellation refers to “set of satellites”
NAVSTAR composed of 24 satellites.
Function : Transmit signal from space on the basis
of which the time and position of the user is
measured.

7. • Control Segment:
Holds:
 5 ground based monitor station
 3 antennas
 a master control station
Function:
Monitor station  master controller
Antenna  GPS receiver

8. User Segment:
• Holds:
GPS Receiver
User community
• Function:
Converts SV Signals into
Position ,
time,
velocity.

9. Working:
Basically working holds three task as follows:
• The GPS transmits signals from the satellites
down to earth.
• GPS Receiver then analyzes the data that was
received.
• Then uses the mathematical concept of
triangulation to compute the exact location of
the user.

10. Accuracy:
It depends upon the types of receiver.
Most hand-held GPS units have about 10-20 meter
accuracy.
Differential GPS (DGPS) obtains much higher
accuracy.
As recorded by the roving units, producing an
accuracy greater than 1 meter.

11. Advantages:
Easy to navigate
GPS works in all weather.
100% coverage on the planet.
Easy to integrate into other technologies like Cell
phone.
Best navigating system in water.

12. Disadvantage:
GPS signals are not accurate due to some obstacles to
the signals.
Atmospheric conditions such as geomagnetic storms
makes it not accurate.
If GPS on a battery operated device, there may be a
battery failure we need an external power supply
which is not always possible

13. GPS Application:
• Google Earth is the most famous application that
uses the signals received by the GPS receivers.
• United States and European countries show a rapid
growth in using GPS for the car navigations and the
number of GPS equipped mobile phone usage.

14. Some Application:
• DeLorme Street Atlas 2010
• Gramin nRoute
• Top Grossing Apps on iTunes
• LOCiMOBILE Apps for tracking people
• GPS Tracking Lite v2.0

15. Recent Development:
Block IIA:
– upgraded version of the GPS Block II satellites.
– Developed by Rockwell International
– As of November 2012, there were 9 Block IIA
satellites.
GPS Block IIR:
-"R" in Block IIR stands for replenishment.
-Developed by Lockheed Martin
-As of November 2012, there were 12 IIR
satellites

16. Current development:
GPS Block III:
• development by Lockheed Martin
• GPS III will provide more powerful signals in
addition to enhanced signal reliability, accuracy,
and integrity.
• GPS III series is the newest block of GPS satellites

17. Future of GPS:
The future will hold a lot more surprises.
Automobiles are tested on moving on their own without
the assistance of a driver.
Tests have begun in using unmanned aircrafts.
The green plant density of a certain area can be
calculated or estimated.

19. Conclusion:
• GPS has truly helped man to advance in more ways
than one.
• It is also going to bring a great revolution by its
development.

20. Presented by,
I.Madhumithah, I M.Sc(CS).,
G.Venkataswamy Naidu College,
Kovilpatti.