x/4/2010 (day) , At Lec (x) ,every one is invited

GGlobal PPositioning SSystem

The History of GPS

Feasibility studies begun in 1960’s. Pentagon appropriates funding in 1973. First satellite launched in 1978. System declared fully operational in

April, 1995.

Historical Development of GPS

1978 -Launch of first GPS satellite.1985 -Kinematic GPS surveying.1989 -Launch of first Block II satelliteWide area differential GPs conceptU.S Coast Guard GPSInformation System (GPSIC).1993 -Real-time Kinematic GPSInitial operational capability (IOC) on December 8.1995 -Full operational capability (FOC) on July 17.1996 -Presendential Decision Directive, first U.S GPS policy.20002000 - Selective availability set to Zero .

Competitors of GPSCompetitors of GPS

• GLONASSGLONASS

- Russian Federation’s satellite - Russian Federation’s satellite navigation systemnavigation system

• GalileoGalileo

-European Union and the European Space -European Union and the European Space AgencyAgency

Introduction

•The global positioning system(GPS)The global positioning system(GPS) is a network of 24 NAVSTAR satellites orbiting at a distance of 20,200kms from the surface of the earth . Originally established by the u.su.s department of defense(DOD).

A visual example of the GPS constellation in motion with the Earth rotating.

A visual example of the GPS constellation in motion with the Earth rotating.

Four Basic Functions of GPS

Position and coordinates.

The distance and direction between any two waypoints, or a position and a waypoint.

Travel progress reports.

Accurate time measurement.

System OverviewSystem Overview

The total GPS configuration is comprised The total GPS configuration is comprised of three distinct segments:of three distinct segments: (1)(1) The space segment-Satellites orbiting The space segment-Satellites orbiting the Earththe Earth (2)(2) The control segment-Stations The control segment-Stations positioned on the Earth’s equator to positioned on the Earth’s equator to control the satellites.control the satellites. (3)(3) The user segment – Anybody that The user segment – Anybody that receives and uses the GPS signalreceives and uses the GPS signal..

Control SegmentControl Segment

Space SegmentSpace Segment

User SegmentUser Segment

Three Segments of the GPS Three Segments of the GPS

Monitor Stations

GroundAntennas

Master Station

User Segment

Military. Search and rescue. Disaster relief. Surveying. Marine, aeronautical and terrestrial navigation. Remote controlled vehicle and robot guidance. Satellite positioning and tracking. Shipping. Geographic Information Systems (GIS). Recreation.

Space Segment

Kwajalein Atoll

US Space Command

Control SegmentControl Segment

Hawaii

Ascension Is.

Diego Garcia

Cape Canaveral

Ground AntennaMaster Control Station Monitor Station

Position is Based on TimePosition is Based on Time

T + 3

Distance between satellite and receiver = “3 times the speed of light”

TSignal leaves satellite at time “T”

Signal is picked up by the receiver at time “T + 3”

Pseudo Random Noise CodePseudo Random Noise Code

Receiver PRN

Satellite PRN

Time Difference

Calculating DistanceCalculating Distance

Velocity x Time = Distance

Radio waves travel at the speed of light, roughly 186,000 miles per second (mps)

If it took 0.06 seconds to receive a signal transmitted by a satellite floating directly

overhead, use this formula to find your distance from the satellite.

186,000 mps x 0.06 seconds = 11,160 miles

TriangulationTriangulationGeometric Principle:

You can find one location if you know its distance from other, already-known locations .

TriangulationTriangulation

TriangulationTriangulation

3-D Trilateration 3-D Trilateration1 Satellite 2 Satellites

3 Satellites

Latitude and LongitudeLatitude and Longitude

Latitude and LongitudeLatitude and Longitude: are spherical coordinates on the surface of the earth. LatitudeLatitude is measured North or South of the Equator. LongitudeLongitude is measured East or West of Greenwich. GPS uses Latitudes and Longitudes to reference locations.

•How to recover A stolen car?

• 1-Know it’s place • 2-Lock it • 3-Go & Get it

A simple question?

GPSGPS Chip receive The satellites signals

And generate the Latitude and Longitude

A mobile basedSystem send (Lat&Lon) viaSMS/GPRSSMS/GPRS

To the car owner

By using any mapping Software

We can knowWere the car is.

How to know the stolen car place?

A built in µ.controllerµ.controller holda text or a code aboutThe lock operation.

The car owner Communicate with

The µ.controllerVia SMS/GPRSSMS/GPRSTo lock the car.

The µ.controllerµ.controller startTo perform the Lock Operation by cutting

The power off.

How to Lock the stolen car ?

Gps Receiver µ.chip

GPS µ.chip Pin out

GPS Serial Communications

GPS Serial Communications

Extracting or Parsing the GGA string

A program can be written to serially read the incoming message strings and determine if it's a GPGGA message. If so, the program can extract and/or display only geospatial information we might want, like the time and longitude/latitude coordinates.

Mobile F-bus

Effective car Lock

Presented by : student / MOHAMED MAGHRBY

Sample frame sent to Nokia 3310 (showed as a Hex dump)

Byte: 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15

Data: 1E 00 0C D1 00 07 00 01 00 03 00 01 60 00 72 D5

Byte 0: This is the F-Bus Frame ID. Cable is 0x1E .Byte 1: the destination address 00 for the phone .

Byte 3: This is the message type or 'command'.

Byte 2:source address. PC's ID byte. 0x0C (Terminal).

Byte 4&5: the message length 4 is MSB & 5 is LSB