surveying using data recorders coupled with total stations advantages
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DESCRIPTION
Laser scanning Introduced in the beginning of nineties Acquire dense and accurate elevation data Distance measured by pulse ranging or multi-frequency sidetone phase With the help of DGPS and INS the position and direction of aircraft (origin of measured distance) is determined Point positions first obtained in eg WGS84; then is converted to a local reference system Used in DEM and 3D city model production