[attachment=13033]
GPS
What is GPS?
GPS is a space based all weather radio navigation system.
GPS
Provides
Position (geographic), Velocity & Time (PVT) Quickly, Economically And Precisely 24 hours a day, anywhere in the world under the sky
Principle of working using GPS
The basis of GPS technology is precise measurement of time;
Use of orbiting satellite position to find location of receiver by method of resection
USER
GPS data processing software
Real time
Post-processing
GPS SIGNAL
CARRIER, f(t)
CODE, C(t)
NAVIGATIONAL DATA, D(t)
CARRIERS
L1 (154f or 1575.42 MHz)
L2 (120f or 1227.60 MHz)
GPS Coordinate system
World Geodetic System, 1984 (WGS84)
GPS receivers Positioning Techniques
Absolute
Relative
Real Time
Post-processing
LIMITATIONS
Ionospheric delay correction is not possible to compute
Weak signal – not available under canopy or under shed
Susceptible to interference
 GPS is getting popularas a means for collectionof data 
GPS DATA 
Reliable
Accurate
Real-time
GPS
Can be used in any conceivable situation
Under the sky
Where the exact position of any object or phenomena involved.