Lecture 5: Data Capture
Distance (m) =
velocity (m/s) * time (s)
What are the three main segments of GPS?
Space, control and user
Distance from one satellite to receiver ->
positions possible on the surface of a sphere
Distance from 2 satellites to receiver ->
positions on a circle
Distance from 3 satellites
two possible locations of which one is generally impossible
Distance from 4 satellites
possible to estimate elevation
What is DOP?
Dilution of precision
Errors connected to GPS measurement
Ephemeris, clock, environmental disturbance, multiple path reflection
What is on screen digitizing?
the geometrical objects are created when we draw them with the mouse in our GIS