Upload
zuliana
View
221
Download
0
Embed Size (px)
Citation preview
8/7/2019 Lecture 7- Global Positioning gps
1/40
Lecture 7:
Global PositioningSystem (GPS)
By: Zuliana Ismail,2010
8/7/2019 Lecture 7- Global Positioning gps
2/40
Home
Previous
Next
Help
Learning Outcomes
At the end of this lecture, the student shouldbe able to:
Explain the basic working principle of GPS
Describe the advantages of GPS
8/7/2019 Lecture 7- Global Positioning gps
3/40
Home
Previous
Next
Help
Introduction
GPS is stands for Global Positioning System.
Official name of GPS is Navigational Satellite
Timing And Ranging Global Positioning System
(NAVSTAR GPS)
8/7/2019 Lecture 7- Global Positioning gps
4/40
Home
Previous
Next
Help
Introduction
8/7/2019 Lecture 7- Global Positioning gps
5/40
Home
Previous
Next
Help
What is GPS-Global Positioning
System?
4 satellites/orbit. Total orbit = 6.
Thus, GPS consists of 24
satellites.
Each satellite orbits the earthevery 12 hours (2 complete
rotations every day).
Thus, every point on the Earthwill always be in radio contact
with at least 4 satellites.
8/7/2019 Lecture 7- Global Positioning gps
6/40
Home
Previous
Next
Help
GPS Segment
8/7/2019 Lecture 7- Global Positioning gps
7/40
Home
Previous
Next
Help
What is the purpose of GPS
The purpose of GPS is to show you your exactposition on the Earth anytime, in any weather,
anywhere.
8/7/2019 Lecture 7- Global Positioning gps
8/40
Home
Previous
Next
Help
Who developed GPS?
First developed by the US DOD (United StatesDepartment of Defense)
Feasibility studies begun in 1960s.Pentagon
appropriates funding in 1973.
First satellite launched in 1978. System
declared fully operational in April, 1995.
Open to the public, 2000. Currently controlled
by the United States Air Force.
It costs about $750 million to manage and
maintain the system per year
8/7/2019 Lecture 7- Global Positioning gps
9/40
Home
Previous
Next
Help Who CanUse GPS
Military
Automobile
Aircraft Navigation
Marine
Individual
8/7/2019 Lecture 7- Global Positioning gps
10/40
Home
Previous
Next
Help
Who can use GPS?
Automobiles: show moving maps (highways,buildings)
Military: target detection.
Aviation: for aircraft navigation
Marine: Provides precise navigation
information to boaters.
8/7/2019 Lecture 7- Global Positioning gps
11/40
Home
Previous
Next
Help
Why do we need GPS?
One drawback of using radio waves generated onthe ground (like NDB,VOR,DME or ILS) is that
you have only two choices:
A system that is very accurate but doesnt cover
a wide area
A system that covers a wide area but is not very
accurate
We need a powerful system such GPS because
GPS can provide accurate information
and cover wide area.
8/7/2019 Lecture 7- Global Positioning gps
12/40
Home
Previous
Next
Help
GPS Frequency
GPS operates in the UHF band.
There are two types of services available:
1. For Civilian/ResearchUse Standard
Positioning System
L1 (1575.42 MHz), L2 (1227.60 MHz), L5
(1176.45 MHz) For Civilian
L4 (1379.913 MHz) For Research
2. ForMilitary Use Precise Positioning System
L3 (1381.05 MHz)
8/7/2019 Lecture 7- Global Positioning gps
13/40
Home
Previous
Next
Help
GPS Receiver
Handheld GPS ReceiversCasio GPS wristwatch
8/7/2019 Lecture 7- Global Positioning gps
14/40
Home
Previous
Next
Help
8/7/2019 Lecture 7- Global Positioning gps
15/40
Home
Previous
Next
Help
H
OW
GPSW
ORKS?
8/7/2019 Lecture 7- Global Positioning gps
16/40
Home
Previous
Next
Help
How GPS works
GPS receivers tuned to the frequencies of GPS satellites.
Each GPS satellites then transmit signals to the GPSreceivers . The signals, moving at the speed of light, c =3 x 10 m/s.
These signals indicates satellites location and the
current time. The GPS receiver measures the time taken for a signal to
travel from satellite to receiver.
The distance to each GPS satellites can be calculated:
Distance = Speed of Light x Time
Knowing the distance from at least 4 GPS satellites, theGPS receiver can calculate the position (latitude,longitude and altitude )
8/7/2019 Lecture 7- Global Positioning gps
17/40
Home
Previous
Next
Help
GPS IN AVIATION
8/7/2019 Lecture 7- Global Positioning gps
18/40
Home
Previous
Next
Help
GPS receiver in the aircrafts cockpit
Can provide the pilot with navigational information in
terms of longitude, latitude and altitude.
8/7/2019 Lecture 7- Global Positioning gps
19/40
Home
Previous
Next
Help
What GPS can tell you?
GPS also can tell you
What direction you are heading
Speed (How fast you are going)
Your altitude
A map to help you arrive at a destination
Distance (How far you have traveled)
Time (How long you have been traveling)
Estimated time of arrival (When you will
arrive)
8/7/2019 Lecture 7- Global Positioning gps
20/40
Home
Previous
Next
Help ADVANTAGES OF GPSINAIRCRAFTNAVIGATION
8/7/2019 Lecture 7- Global Positioning gps
21/40
Home
Previous
Next
Help
ADVANTAGES OF GPS
in AIRCRAFTNAVIGATION
GPS can reduce the aircraft delays problem,
GPS can reduce journey time and fuel
consumption
GPS can maintain high levels of flight safety. GPS can increase airway & landing capacity for
aircraft.
GPS more economical
8/7/2019 Lecture 7- Global Positioning gps
22/40
Home
Previous
Next
Help
A GPS receiver in the cockpit
provides the pilot with
accurate position data and
helps him keep the airplane on
course.
8/7/2019 Lecture 7- Global Positioning gps
23/40
Home
Previous
Next
Help
Using GPS, aircraft can fly the
most direct routes between
airports
8/7/2019 Lecture 7- Global Positioning gps
24/40
Home
Previous
Next
Help
Advantages of using GPS in Aircraft
Navigation
GPS can reduce the aircraft delays problem GPS can provide accurate & continuous data
during all-weather condition.
This can avoid flight delays.
GPS can reduce fuel consumption Civil aircraft typically fly from one waypoint
to another.
With GPS, an aircraft's computers can beprogrammed to fly a direct route to adestination.
This can save fuel and time
8/7/2019 Lecture 7- Global Positioning gps
25/40
Home
Previous
Next
Help
Advantages of using GPS in Aircraft
Navigation
GPS can maintain high levels of flight safety. Improved situational awareness (quick alert
about emergency)
GPS also can simplify and improve themethod of guiding planes to a safe landing,especially in poor weather.
GPS can increase airway & landing capacity for
aircraft. GPS system more flexible. Many aircrafts can
depend on GPS system at one time.
8/7/2019 Lecture 7- Global Positioning gps
26/40
Home
Previous
Next
Help
Advantages of using GPS in Aircraft
Navigation
GPS more economical
Maintain economies from reduced
maintenance and operation of ground-based
systems (such as VOR/DME/NDB station)
8/7/2019 Lecture 7- Global Positioning gps
27/40
Home
Previous
Next
Help
Waypoints
Waypoints are locations or landmarks that canbe stored in your GPS.
Waypoints may be entered directly by taking areading with the unit at the location itself,
giving it a name, and then saving the point. Once entered and saved, a waypoint remains
unchanged in the receivers memory untiledited or deleted.
8/7/2019 Lecture 7- Global Positioning gps
28/40
Home
Previous
Next
Help
Waypoints
Latitude and
Longitude
Your location
Direction of
waypoint
Date
and
Time
Waypoint
8/7/2019 Lecture 7- Global Positioning gps
29/40
Home
Previous
Next
Help GPS APPLICATION FORNAVIGATION SYSTEM
8/7/2019 Lecture 7- Global Positioning gps
30/40
Home
Previous
Next
Help
GPS NAVIGATION SYSTEM
There are two advanced GPS NAVIGATIONSystem which are
1. LAAS - Local Area Augmentation
System.
2. WAAS - Wide Area Augmentation
System
8/7/2019 Lecture 7- Global Positioning gps
31/40
Home
Previous
Next
Help
Local Area Augmentation System
(LAAS)
LAAS is a precision approach and landingsystem that relies on the Global Positioning
System (GPS) to broadcast highly accurate
information to aircraft on the final phases of a
flight.
LAAS support precision approaches and landing
capability to aircraft operating within a 20- to
30-mile radius of the airport.
LAAS approaches will be designed to avoid
obstacles, restricted airspace, noise-sensitive
areas, or congested airspace.
8/7/2019 Lecture 7- Global Positioning gps
32/40
Home
Previous
Next
Help
Local Area Augmentation System (LAAS)
One LAAS coversmultiple runway ends
Contributing
technology for high
precision terminal area
navigation services.
Quick data transferring
among LAAS, Aircraftand GPS satellites
8/7/2019 Lecture 7- Global Positioning gps
33/40
Home
Previous
Next
Help
Benefits of LAAS
Replaces ILS systems that are expensive tomaintain
Increases efficiency of arrival and departure
operations and improves usage of runway
capacity
Supports fuel efficiency.
Improves access to airports during extremely
low visibility operations
8/7/2019 Lecture 7- Global Positioning gps
34/40
Home
Previous
Next
Help
Wide Area Augmentation SystemWide Area Augmentation System
(WAAS)(WAAS)
38 ReferenceStations
3 MasterStations
4 GroundEarth Stations
2 GeostationarySatellite Links
2 OperationalControl Centers
8/7/2019 Lecture 7- Global Positioning gps
35/40
Home
Previous
Next
Help
WAAS Benefits
Serves all classes of aircraft during flightoperations in all weather conditions at all
locations.
Provides precise navigation and landing
guidance to pilots at all airports, including
thousands that have no ground-based
navigation aids
Overcomes obstacles to ground-based systems,such as mountainous terrain
8/7/2019 Lecture 7- Global Positioning gps
36/40
Home
Previous
Next
Help
WAAS Benefits
Reduces operating and maintenance costsassociated with ground-based navigation aids
Makes more airspace usable to pilots, provides
more direct en-route paths, and provides new
precision approach services to runway ends
Through international cooperation provides a
global navigation system for all users
8/7/2019 Lecture 7- Global Positioning gps
37/40
Home
Previous
Next
Help
GPS Limitations
The GPS must see the satellites, so it does notwork well in dense forests, inside caves,
underwater, or inside buildings.
Signal Interference: Sometimes the signals
interfered before they reach the receivers.
Changing atmospheric conditions change the
speed of the GPS signals as they pass through
the Earth's atmosphere
8/7/2019 Lecture 7- Global Positioning gps
38/40
Home
Previous
Next
Help
Obstruction
8/7/2019 Lecture 7- Global Positioning gps
39/40
Home
Previous
Next
Help
Earths Atmosphere
Solid Structures
Metal Electro-magnetic Fields
Signal Interference
8/7/2019 Lecture 7- Global Positioning gps
40/40
Home
Previous
Next
Help
Question Bank
1. Explain how GPS works. (9m)
2. Describe 3 advantages of GPS. (6m)