The Global Positioning System (GPS) is a satellite-based navigation system consisting of 24 satellites maintained by the U.S. government that allows GPS receivers to determine their precise location. GPS was developed in 1973 by the U.S. Department of Defense and uses satellites to transmit timing and position data that allows receivers to calculate their position via triangulation. The current GPS architecture consists of three segments: the space segment of 24 satellites, a control segment of ground stations, and the user segment of GPS receivers.

1. Global
Positioning
System
By :
Pavitra Malpani
Diksha Rai
B.E. IIIrd sem
SATI VIDISHA

2. WHAT IS
GPS ??
 Space based navigation system.
 Constellation of 24 satellites.
 Maintained by US govt.
 Freely accessible to anyone with gps
receiver.
 GPS satellites also called NAVSTAR.

3.  Developed in 1973.
 Created & realized by U.S. dept of
defense (DoD).
 Originally run with 24 satellites.
 Bradford Parkinson,Roger L.
Easton,& Ivan A. Getting are
credited with inventing it.

4. A GPS receiver calculates its position by precisely
timing the signals sent by GPS satellites high above
the Earth. Each satellite continually transmits
messages that include:
1. The time the message was transmitted and,
2. Satellite position at time of message transmission.

6. The current GPS consists of three major
segments. These are:
1. Space segment (SS)
2. Control segment (CS)
3. User segment (US)

8.  It composed of 24
space vehicles.
 Orbiting at an altitude of
approximately 20,200 km
(12,600 mi)
 Orbital radius of
approximately 26,600 km
(16,500 mi)

9. The control segment is composed of:
1.A master control station (MCS),
2.An alternate master control station,
3.Four dedicated ground antennas, and
4.Six dedicated monitor stations

12. The GPS receiver uses the following information to
determine a position…
a)Precise location of
satellites.

13. b) Distance from each satellite.
c) Triangulation to determine a
location.

14. There are several different models and types of GPS receivers.
When working on an incident with a GPS receiver it is
important to have -
COMPASS
&
MAPS
BATTERIES GPS CABLES

15. EXTERNAL
ANTENNAE
TAKING
NOTES

16. The GPS is not a perfect system. There are
several different types of errors that can
occur when using a GPS receiver, for
example:
USER ERRORS:
Inputting incorrect information into a GPS
receiver .

17. MULTIPATH INTERFERANCE:
Multipath interference is caused
by the satellite signal reflecting
off of vehicles, buildings, power
lines, water and other interfering
objects
ORBIT ERRORS:
Satellite orbit pertains to the altitude,
position, and speed of the satellite.
Satellite orbits vary due to gravitational
pull and solar pressure fluctuations.

18. ATMOSPHERIC ERRORS:
Error are caused by atmospheric conditions such as
ionized air, humidity, temperature, pressure ,etc.

19. Wide Area Augmentation System
The Wide Area Augmentation System (WAAS) is
an experimental system designed to enhance and
improve aircraft flight approaches using GPS and
WAAS satellites. The WAAS can be considered an
advanced real-time differential GPS. Many GPS
receivers are now capable of receiving the WAAS
signal.

21. GPS applications are all those applications
that use GPS to collect position, velocity and
time information to be used by the
application.
AGRICULTURE
AVIATION & SHIPPING
RAIL APPLICATIONS
ROAD APPLICATIONS
SURVEYING & MAPPING