Spectra Precision ProMark 800 Reference Manual - Manual (Page 45)

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Chapter 4. Precise Surveying - Field Applications &
Concepts
Introduction to Precise Surveying
GNSS precise surveying relies on the use of specific
algorithms involved in the processing of carrier phase
measurements. Centimeter precision obtained in precise
surveying results from the successful processing of these
measurements.
Carrier phase measurements are derived from the signals the
surveying equipment receives and decodes from the visible
GNSS constellations.
There are two different ways of implementing the processing
algorithms, each of them defining a specific family of
surveying methods:
• RTK real-time surveying.
• Post-processed surveying
This chapter introduces the basics of the two surveying
families.
Note that Spectra Precision RTK-capable receivers can also
be used for post-processed surveys, either simultaneously
with RTK or as post-processed only. With these receivers,
post-processed surveying can be used either as a backup
method or as an excellent source of comparison for checking
your real-time survey results.
Key Terms and
Expressions
Carrier: Refers to the electromagnetic wave carrying signals
transmitted by satellites (cf. L1 and L2 carriers).
Carrier phase measurements: Refers to measurements
performed by a receiver from the received signals to
determine the fractional phase of the carrier at the receiver
location. This fractional phase is then added to the integer
number of full carrier cycles between the receiver and the
satellite, thus converting the carrier phase measurement into
an extremely accurate range measurement.