Spectra Precision ProMark 800 Reference Manual - Manual (Page 101)

89
RTK Implementation
configuration, a typical latency time in Spectra Precision
receivers is 15 ms.
Use Context. Fast RTK should be used when consistent and
high-rate position updates are required, such as in machine
control or field operator guidance, and when consistent
position accuracy is not the highest priority.
Benefits. The position output rate is less sensitive to the rate
at which the rover receives RTK correction data.
The latency is shorter than in time-tagged mode thanks to the
extrapolation process.
The rover will continue to compute positions even if there is
a minor interruption in the RTK correction data. Under good
conditions, centimeter-level accuracy can be maintained in
the rover even if no RTK correction data is received for several
seconds.
Drawback. Accuracy is slightly degraded with extrapolated
solutions because the corrections slowly deviate from the true
correction.
Insensitivity of the Fast RTK Mode to Missing Base Epochs
The diagram below shows how the two output modes react
when an epoch of RTK correction data is missing.