SURVEYING
At the beginning of the century, surveyors had improved the
older chains and ropes, but still faced the problem of accurate long distance measurement.Measure
long distances using two microwave transmitters / receivers.EDM units use a
phase shift of light waves of multiple frequencies to find a distance. of the
measure of the chain measuring between points kilometers away at a single time.
The advances in electronics allowed the miniaturization of
the EDM. In the 1970s, the first instruments that combined the measurement of
angle and distance appeared, and were known as total stations. Manufacturers
added more equipment by degrees, providing improvements in accuracy and speed
of measurement.
The first satellite positioning system was the TRANSIT
system of the United States Navy. The first successful launch took place in
1960. The main purpose of the system was to provide positional information to
Polaris missile submarines.
The surveyors discovered that they could use field receivers to determine the location of a point. The poor satellite coverage and the great team made the observations laborious and inaccurate. The main use was to establish landmarks in remote places.
The surveyors discovered that they could use field receivers to determine the location of a point. The poor satellite coverage and the great team made the observations laborious and inaccurate. The main use was to establish landmarks in remote places.
The US Air Force UU It launched the first satellite
prototype of the Global Positioning System (GPS) in 1978. The GPS used a larger
satellite constellation and improved signal transmission to provide more
precision. The first GPS observations required several hours of observations by
a static receiver to meet the accuracy requirements of the survey.
Recent improvements in both satellites and receivers allow real-time kinematic surveying (RTK). RTK surveys obtain high precision measurements using a fixed base station and a second mobile antenna. The position of the mobile antenna can be traced.
Recent improvements in both satellites and receivers allow real-time kinematic surveying (RTK). RTK surveys obtain high precision measurements using a fixed base station and a second mobile antenna. The position of the mobile antenna can be traced.
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