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Appl icatio ns – Trimble Outdoors 5700 User Manual

Page 114

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8

Real-Time Kinematic (RTK) Surveying

9 8

5700 GPS Receiver User Guide

Appl

icatio

ns

Environmental factors

Table 8.2 lists some of the environmental factors that can affect the
quality of GPS measurements.

Table 8.2

Environmental factors affecting measurement quality

Environmental
factor

Effect

Solution

Ionospheric activity

Can cause rapid changes in the GPS
signal delay, even between receivers
a few kilometers apart, and increase
RTK initialization time.

Avoid surveying around midday
when ionospheric activity is high.

Tropospheric
activity

Causes a delay in the GPS signals
which varies with height above sea
level, prevailing weather conditions,
and satellite elevation.

Locate the reference station at
approximately the same elevation
as the rover.

Signal obstructions

Limit the number of visible satellites
and can also induce signal multipath.

Locate the reference station in a
clear environment with an open
view of the sky.

Multipath

Can cause signal reflection before
reception at the GPS antenna.

Use an antenna with a ground

plane.

Radio interference

Can cause serious degradation in
signal quality or complete loss of
signal tracking.

Do not locate the reference
station in an area where radio
transmission interference may be
a problem.