NavCom SF-3050 Rev.B - Manual (Page 110)

SF-3050 User Guide – Rev B
Basics of RTK Surveying
RTK (Real-Time Kinematic) is a GNSS system that
yields very accurate 3D position fixes immediately in
real-time.
A reference station (base station) transmits its GNSS
position to roving receivers as the base receiver
generates them. The roving receivers use the
reference station readings to differentially correct their
own positions. Accuracies of a few centimeters in all
three dimensions are possible. RTK requires
multi-frequency GNSS receivers and high speed
radio modems.
Proper setup of a reference station minimizes GNSS
errors in the rover. The reference GNSS sensor is set
up at a known surveyed location. With this position
locked in, it transmits its code, clock, and reference
station coordinate information to the roving sensor(s).
The roving sensor(s) uses this information to correct
each GNSS measurement it receives.
The SF-3050S, when configured as a reference
station, can transmit corrections to any number of
roving receivers capable of picking up the radio signal
and decoding one of these correction formats
(NavCom proprietary, RTCM 3.0, CMR, CMR+, or
RTCM 3.1, types 1014-1017 for Network RTK
1
). The
signal can be received in less than ideal
environments, though some data loss may occur.
Setup of the reference station sensor above the roving
sensors is recommended to enable transmission to all
rovers in all directions with minimal obstruction. High
frequency radio signals generally travel a shorter
distance than lower frequency signals, and do not
penetrate obstructions as well over distance. Figure 67
and Figure 68 illustrate proper and improper RTK
1
Network RTK is not supported in software version 1.0.
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