Sokkia GSR2700 IS, Operation Manuals, Page: 76 / 87

Glossary
GSR2700 IS Operations Manual 65
O
Occupation time— A period of continuous data of sufficient quality
for post-processing.
P
P-Code (Precise or Protected)— The protected or precise code used
on both LI and L2 GPS frequencies.
Phase Center— The phase center of a GPS antenna is the physical
location on the antenna where the raw GPS signals are observed. This
is the physical location where the computed position will be
determined.
Pseudorange— The calculated range from the GPS receiver to the
satellite. It is determined by taking the difference between the
measured satellite transmit time and the receiver time of
measurement, and multiplying it by the speed of light.
R
RMS— See Root-Mean-Square (RMS) .
Radio Technical Commission for Maritime Services (RTCM)—
Radio Technical Commission for Maritime Services. An organization
that developed and defined the SC-104 message format for
differential positioning.
Raw data— GPS data which has not been processed or differentially
corrected.
Real-time Kinematic (RTK)— A type of differential positioning
based on observations of carrier phase.
Reference station— See Base station .
Rover receiver— The GPS receiver that moves from site to site
during an RTK survey. The receiver does not know its position and
needs to receive measurements from a base station to calculate
differential GPS positions at each point.
Root-Mean-Square (RMS)— A statistical measure of the scatter of
computed positions about a “best fit” position solution.