PPT: GPS and Photogrammetry | Geomatics Engineering (Surveying) - Civil Engineering (CE) PDF Download

 Page 1


GPS and 
Photogrammetry
Advanced geospatial technologies revolutionizing civil 
engineering practices. This presentation explores 
satellite positioning systems and image-based 
measurement techniques that enable precise 
surveying and mapping solutions.
Page 2


GPS and 
Photogrammetry
Advanced geospatial technologies revolutionizing civil 
engineering practices. This presentation explores 
satellite positioning systems and image-based 
measurement techniques that enable precise 
surveying and mapping solutions.
What is GPS?
Satellite-Based 
Navigation
A network of satellites 
continuously transmitting 
signals from space. 
Receivers calculate precise 
position coordinates 
anywhere on Earth.
Global Coverage
Functions 24/7 in all weather 
conditions. Provides 
positioning services across 
the entire planet with no 
subscription fees.
Multifunctional System
Delivers location, velocity, and precise timing data. Supports 
countless applications across industries and everyday use.
Page 3


GPS and 
Photogrammetry
Advanced geospatial technologies revolutionizing civil 
engineering practices. This presentation explores 
satellite positioning systems and image-based 
measurement techniques that enable precise 
surveying and mapping solutions.
What is GPS?
Satellite-Based 
Navigation
A network of satellites 
continuously transmitting 
signals from space. 
Receivers calculate precise 
position coordinates 
anywhere on Earth.
Global Coverage
Functions 24/7 in all weather 
conditions. Provides 
positioning services across 
the entire planet with no 
subscription fees.
Multifunctional System
Delivers location, velocity, and precise timing data. Supports 
countless applications across industries and everyday use.
GPS Segments
Space Segment
Constellation of approximately 
24 operational satellites in 
medium Earth orbit. Transmits 
signals on multiple frequencies 
for redundancy.
Control Segment
Network of ground stations 
monitoring satellite health. 
Updates orbital parameters and 
ensures system accuracy 
worldwide.
User Segment
Receivers in devices calculating 
position from satellite signals. 
Ranges from smartphones to 
high-precision survey equipment.
Page 4


GPS and 
Photogrammetry
Advanced geospatial technologies revolutionizing civil 
engineering practices. This presentation explores 
satellite positioning systems and image-based 
measurement techniques that enable precise 
surveying and mapping solutions.
What is GPS?
Satellite-Based 
Navigation
A network of satellites 
continuously transmitting 
signals from space. 
Receivers calculate precise 
position coordinates 
anywhere on Earth.
Global Coverage
Functions 24/7 in all weather 
conditions. Provides 
positioning services across 
the entire planet with no 
subscription fees.
Multifunctional System
Delivers location, velocity, and precise timing data. Supports 
countless applications across industries and everyday use.
GPS Segments
Space Segment
Constellation of approximately 
24 operational satellites in 
medium Earth orbit. Transmits 
signals on multiple frequencies 
for redundancy.
Control Segment
Network of ground stations 
monitoring satellite health. 
Updates orbital parameters and 
ensures system accuracy 
worldwide.
User Segment
Receivers in devices calculating 
position from satellite signals. 
Ranges from smartphones to 
high-precision survey equipment.
Working Principle of GPS
Signal Transmission
Satellites broadcast precise time signals using atomic clocks. Each 
signal contains satellite position and timing data.
Distance Calculation
Receiver measures time delay of signals. Distance = Speed of light 
× Time difference.
Trilateration
Multiple satellite distances create intersecting spheres. Position is 
determined at their intersection point.
Position Solution
Minimum 4 satellites needed for 3D positioning. Fourth satellite 
resolves timing inaccuracies in receiver clock.
Page 5


GPS and 
Photogrammetry
Advanced geospatial technologies revolutionizing civil 
engineering practices. This presentation explores 
satellite positioning systems and image-based 
measurement techniques that enable precise 
surveying and mapping solutions.
What is GPS?
Satellite-Based 
Navigation
A network of satellites 
continuously transmitting 
signals from space. 
Receivers calculate precise 
position coordinates 
anywhere on Earth.
Global Coverage
Functions 24/7 in all weather 
conditions. Provides 
positioning services across 
the entire planet with no 
subscription fees.
Multifunctional System
Delivers location, velocity, and precise timing data. Supports 
countless applications across industries and everyday use.
GPS Segments
Space Segment
Constellation of approximately 
24 operational satellites in 
medium Earth orbit. Transmits 
signals on multiple frequencies 
for redundancy.
Control Segment
Network of ground stations 
monitoring satellite health. 
Updates orbital parameters and 
ensures system accuracy 
worldwide.
User Segment
Receivers in devices calculating 
position from satellite signals. 
Ranges from smartphones to 
high-precision survey equipment.
Working Principle of GPS
Signal Transmission
Satellites broadcast precise time signals using atomic clocks. Each 
signal contains satellite position and timing data.
Distance Calculation
Receiver measures time delay of signals. Distance = Speed of light 
× Time difference.
Trilateration
Multiple satellite distances create intersecting spheres. Position is 
determined at their intersection point.
Position Solution
Minimum 4 satellites needed for 3D positioning. Fourth satellite 
resolves timing inaccuracies in receiver clock.
GPS Accuracy Factors
Satellite Geometry (PDOP)
Spatial distribution of satellites affects precision. Lower PDOP 
values indicate better geometric configuration for accuracy.
Atmospheric Interference
Ionospheric and tropospheric layers delay signal propagation. 
Dual-frequency receivers can compensate for these effects.
Signal Multipath
Signals bounce off buildings and terrain. Creates multiple 
signal paths causing position errors.
Receiver Quality
Higher-grade receivers provide better accuracy. Professional 
survey equipment achieves centimeter-level precision.