Spectra Precision ProMark 800 Reference Manual User Manual
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Precise Surveying - Field Applications & Concepts
the surveyor has full control over the base data sent to the
rover.
Constellation: Set of GNSS satellites visible from a given
observation point on the Earth.
Data Link: A communication means allowing transfer of RTK
correction data from a base to a rover.
Occupation Time: Time spent on a survey point without
moving (“static” occupation) the antenna pole and keeping it
vertical. Not relevant to logging points in continuous mode
where each point recorded is a single epoch measurement.
Position Averaging: Process run in a rover during an
occupation consisting of collecting all the position solutions
delivered over this period and computing an average position
from all these solutions. The resulting solution, which is
statistically more accurate than each of the individual
solutions from which it is derived, is assigned to the point on
which the occupation took place.
Rover-Only Configuration: Refers to an RTK surveying system
consisting only of a rover, which uses data from a third-party
base or network to deliver centimeter-accurate positions.
RTK Correction Data or base data: Carrier phase differential
data generated by a base allowing a rover processing this data
to deliver centimeter-accurate positions.
TTFF: Time To First Fix. The time required for an RTK system
to get initialized, i.e. the time elapsed since power up before
it can deliver a “fixed” RTK position.
Implementation
Rules
1. Two systems are used: one (the base) is operated on a
chosen point while the other (the rover) is used in the
working area for the survey.
2. The base will be either:
–
A user-owned base fitted with a UHF radio, a GSM
modem or any other suitable data link. To choose a
reference location for the base, see Choosing a
–
A third-party operated base (Direct IP) or base network
(NTRIP) that delivers its data to the rover via a GSM/
GPRS or CDMA modem.