1. Tanta University
Faculty of Science
Department of Geology
Global Positioning System
GPS
Submitted by
Mohamed Mahmoud Ahmed El-shora
Supervised By
Prof. Dr. Shadiya Taha El-khodary
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2. Global Positioning System
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3. Introduction
 Global Positioning System or
GPS is a constellation of 27
satellites orbiting the earth at
about 12000 miles. These
satellites are continuously
transmitting a signal and anyone
with a GPS receiver on earth
can receive these transmissions
at no charge. By measuring the
travel time of signals transmitted
from each satellite, a GPS
receiver can calculate its
distance from the satellite.
Satellite positions are used by
receivers as precise reference
points to determine the location
of the GPS receiver.
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4. Introduction
 . If a receiver can receive
signals from at least 4
satellites, it can determine
latitude, longitude, altitude
and time. If it can receive
signals from 3 satellites, it
can determine latitude,
longitude and time. The
satellites are in orbits such
that at any time anywhere
on the planet one should
be able to receive signals
from at least 4 satellites.
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5. Global Positioning System
GPS
 The Global Positioning System
(GPS) is a space-based global
navigation satellite system
(GNSS)
 GPS is a satellite system which
enables anyone with a GPS
receiver to establish their
position, altitude and speed. It
was developed by the USA and
can be used by anyone.
 In this picture: Artist's
conception of GPS Block II-F
satellite in orbit
GPS Satellite NASA art-ii-f
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6. Comparison of GNSS systems
System Country Number of Orbital
satellites height &
period
GPS United 24 ≤ km, 20,200
States (24-32) 12.0h
COMPASS China 35 km, 21,150
12.6h
GALILEO European 22 km, 23,222
Union 14.1h
GLONASS Russia 24 km, 19,100
11.3h
•Core Satellite navigation systems, currently GPS, Galileo and
GLONASS.
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7. Global Positioning System
GPS
Consists of two main parts,
the transmitter and receiver
Part of the sender are those satellites, but receiver devices
are small hands very sophisticated work in electronic circuits
called Microprocessor
The location is determined in two ways:
First by the so-called Doppler Shift of the
electromagnetic waves received from the satellite,
and the displacement caused by the relative speed
between the Earth and satellite
The second way to determine the location based on
measuring the time delay between the electromagnetic
waves received from satellites.
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8. Measuring Distance
A GPS receiver determines its
position by using the signals that it
observes from different satellites.
Since the receiver must solve for its
position (X, Y, Z) and the clock error
(x), four SVs are required to solve
receiver's position using the following
:four equations
Where (x1,y1) (x2,y2) (x3,y3)
and (x4, y4) stand for the
location of satellites and R1,
R2, R3, R4 are the distances
of satellites from the receiver
).position (Figure-3
Hence solving the four
equations for four unknowns
X, Y, Z and x, the position or
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location of the station is 8
. calculated

9. Global Positioning System
GPS
The analysis of these data by the GPS devices that contain
software provider a lot of information and physical variables such
as the impact the atmosphere on electromagnetic waves, as well
as the influence of gravity and the situation of climate, as the
program contains detailed maps of the land, cities and streets,
where, and the most important geographical features and other
information important.
It could be argued that the system of Global Positioning System
GPS is based on an integrated system of satellites that operate
within a system called Sophisticated Network Of Satellites, and
these satellites will scan the globe twice every 23 hours and 56
minutes, as distributed these satellites on 6 levels of rotation of
each level makes 55 degrees with the other level, and in each level
there are three satellites.
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11. GPS
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12. Models for GPS
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13. Models for GPS
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14. GPS MAP
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15. GPS Maps Of Egypt
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16. Structure of GPS
:GPS consists of three parts
,the space segment
,the control segment
.and the user segment
The space segment is composed of 24 to 32 satellites in medium
Earth orbit ,These space vehicles (SVs) send radio signals from
space.Their configuration provides user with between five and eight
.SVs visible from any point on the earth
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17. Structure of GPS
 The control segment is
composed of a master control
station, an alternate master
control station & a host of
dedicated & shared ground
antennas & monitor stations.
 The Control Segment consists
of a system of tracking stations
located around the world.These
stations measure signals from
the SVs, compute orbital data,
upload data to the SVs, then the
SVs send data to GPS receivers
over radio signals.
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18. Structure of GPS
 The User Segment consists of
the GPS receivers and the user
community.
– GPS receivers convert SV signals
into position, velocity, and
time estimates.
– Four satellites are required to
compute the four dimensions of
X, Y, Z (position) and T (time).
 GPS receivers are used for
navigation, surveying, time
dissemination, and other
research.
 Navigation receivers are
made for aircraft, ships,
ground vehicles, and for
hand carrying by individuals.
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21. GPS Structure
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22. Uses Of GPS
There are many uses of this system are difficult to restrict, at the
present time, proceeded a lot of companies, global transportation and
shipping companies manufactured to follow the movement of
machinery and vessels by this system very effective, as has been the
introduction of this system in a lot of cars newly, which provides
drivers for detailed maps of places and streets where they are
located, and the best and shortest routes, which should conduct
during their movements daily.
Also saw this system for other uses by the airlines and air navigation
to guide planes in the sky very precisely, and most recently was the
introduction of this system in monitoring systems, air and track
hurricanes, wind and waves raging in the oceans, as used by the
bodies of scientific research to track migration birds, aquatic and
forest fire monitoring and movement of icebergs.
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23. Uses Of GPS
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24. Applications of GPS
 GPS has become a widely
used and useful tool for
commerce, scientific uses,
tracking and surveillance.
GPS's accurate timing
facilitates everyday
activities such as banking,
mobile phone operations,
and even the control of
power grids. Farmers,
surveyors, geologists and
countless others perform
their work more efficiently,
safely, economically, and
accurately.
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25. Applications of GPS
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