Seminar on GPS

Shaeq Ahmad

Electronics and Communication Engineering

6th Semester

Techno India College of Technology

What is GPS..?

• Acronym for ‘Global Positioning System’.• Official name of GPS is

Navigational Satellite Timing And Ranging Global Positioning System (NAVSTAR GPS)

• Global Positioning Systems (GPS) is a form of Global Navigation Satellite System (GNSS)

• A worldwide satellite based system for surveying, map-making, Positioning and Navigational purposes.

• Provides location & time information anywhere at any instant of time.

History of GPS

• In 1973, the US Air Force proposed a new system for navigation using satellites

• Developed by the United States Department of Defense (DOD).

• Its started with a unison of 24 satellites

• Initially developed for Military

• User specific precision level adopted when made common for Civilian Use.

• Currently USAF has 63 satellites.

GPS Functionality

• GPS systems are made up of 3 segments

– Space Segment (SS)

– Control Segment (CS)

• Master Control System

• Monitor Stations

• Ground Antennas

– User Segment (US)

Space Segment

Space Segment

• GPS satellites fly in circular orbits at an altitude of 20,200 km and with a period of 12 hours.

• Powered by solar cells, the satellites continuously orient themselves to point their solar panels toward the sun and their antenna toward the earth.

• Each planes has about 55° tilt relative to Earth's equator.

Space Segment

• The satellites are arranged so that at least 6 of are within line of sight from anywhere at a time.

Control Segment

• The Control System is composed of1. a Master Control Station.2. an alternate MCS.3. four dedicated Ground Antennas.4. six dedicated Monitor Stations.

User Segment

• GPS Receivers composed of an Antenna, tuned to the frequencies transmitted by the satellites, receiver-processors, and a highly stable clock(Crystal Oscillator).

• They may also include a display for providing location and speed information to the user

GPS Frequency OverviewBand Frequency Description

L1 1575.42 MHz

Coarse-acquisition (C/A) and

encrypted precision (P(Y))

codes, plus the L1 civilian

(L1C) and military (M) codes

on future Block III satellites.

L2 1227.60 MHz

P(Y) code, plus the L2C and

military codes on the Block

IIR-M and newer satellites.

L3 1381.05 MHzUsed for nuclear detonation

(NUDET) detection.

GPS Frequency OverviewBand Frequency Description

L4 1379.913 MHzBeing studied for additional

ionospheric correction.

L5 1176.45 MHzProposed for use as a civilian

safety-of-life (Sol) signal.

GPS Signal

Latest Developments

• ISRO to have its regional fully operational GPS by mid-2015.

• Named Indian Regional Navigational Satellite System (IRNSS)

• System to have a constellation of seven satellites

• Two out of seven have been successfully stationed

Application of GPS

• Military

• Automobiles are often equipped GPS receivers

• Aircrafts

• Agriculture

• Disaster Relief

• Marine

Application of GPS

Application of GPS

• An artificial archipelago created by land reclamation

Application of GPS

Usage of GPS in

Trimble Backpack.

More Applications

Now let us have a quick look

what GPS is to all of us

Rajarhat Area

‘Satellite Vision’ On

Our College

Conclusion

• GPS will find more civilian uses

• It can be used as a safety device

References

• http://www.physics.hmc.edu/research/geo/gps.html

• http://www.trackingtheworld.com/articles/the-future-of-gps-tracking-systems.php

• http://www.ndtv.com/article/india/isro-to-give-india-its-desi-gps-504094