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Real Time Kinematic Surveying
With RTK surveying, as with kinematic surveying
described above, one receiver serves as the reference
station and conducts observations with its antenna
affixed to a stationary tripod or some other device.
The other receiver functions as a rover and conducts
observations (using an antenna) affixed to a mobile
pole and moved to observation points.
Unlike post-processed kinematic surveys, RTK sur-
veys utilize a communications link between the Base
and Rover. Using a radio modem link, the Base receiv-
er transmits its measurement and location data to
the Rover receiver. The Rover, based on the transmit-
ted data and its own observation data, immediately
conducts a baseline analysis and outputs the results.
Usually, the receiver will start to output the coor-
dinates of the antenna’s phase center along with the
solution type within 10–30 seconds. However, UHF ra-
dios and GSM phones may take as long as 60 seconds
to synchronize. The geodetic coordinates displayed
on the Location tab are always computed in WGS84
and have four solution types.
• Standalone – where the receiver computes 3D
coordinates in autonomous mode without using
differential corrections.
• Code differential – where the Rover receiver com-
putes the current relative coordinate in differential
mode using only pseudo ranges.
• RTK float – where the Rover receiver computes
the current relative coordinates in differential
mode using both pseudo ranges and phases; how-
ever, with a float solution, the phase ambiguity is
not a fixed integer number and the “float” estimate
is used instead.
• RTK fixed – where the Rover receiver computes
current relative coordinates, with ambiguity fixing,
in differential mode. The LQ field reflects the status
of the received differential messages and contains
the following information:
• Data link quality in percentage
• Time (in seconds) elapsed since the last received
message
• Total number of received correct messages (depen-
dent on the message type received)
• Total number of received corrupt messages (de-
pendent on the message type received)
• If the receiver is not (for some reason) receiving dif-
ferential corrections, or if none of the ports has been
configured to receive differential corrections, the
LQ field will either be empty or it will look like this:
100%(999,0000,0000).
Receiver and File
Maintenance
If post-processing the data after completing a mea-
suring, the data in the receiver’s memory will need
to be downloaded to a computer. Downloading and
deleting files will also prepare the receiver’s memory
for the next measuring. Occasionally, the receiver’s
NVRAM may need to be cleared to eliminate commu-
nication or tracking problems. As project expectations
expand, the receiver’s OAF may need to be updated
to provide expanded operation and functionality. The
receiver requires firmware to properly operate and
provide appropriate functionality. As JAVAD GNSS re-
leases firmware updates, loading these updates into
the receiver will ensure that the receiver operates at
its full potential.
Deleting Files and Downloading Files to a
Computer
When your measuring finishes, you can down-
load your measuring files to a computer for storage,
post-processing, or backup. Also, the DELTA memo-
ry holds a finite amount of files and information, so
downloading the files to a computer ensures that no
files are lost. You should download files as soon as
possible after collecting data at the jobsite. NetView
provides a File Manager to download files to your
computer and delete files from the receiver DELTA.
Connect your receiver and computer. Start NetView.
Establish connection between NetView and receiver.
Click File on the left panel. On the right panel ap-
pears the list of files, saved in receiver’s memory.
Select the file(s) to download:
Figure 11.
Downloading files
Click the
Download
button. During the download,
