Gnss Receiver Offset - Spectracom VersaSync User Manual

3.3.3.6

GNSS Receiver Offset

The Offset setting in the GNSS configuration window ( INTERFACES > GNSS 0 > " Edit ") allows
you to enter an offset to the GNSS time and 1PPS reference in order to account for antenna
cable delays or other latencies (entered and displayed in nanoseconds).
By setting the correct Offset value, you can offset the system's
compensate for the antenna and in-line amplifier delays. Under typical conditions, the expected
cable and amplifier delays are negligible. You can calculate the delay based on the man-
ufacture's specifications.
The offset range is ±½ seconds (i.e. ±500 ms, or ±500 000 000 ns). The default value is
0 nanoseconds, and the resolution is 1 nanosecond.
Configuring a GNSS receiver offset
To configure the GNSS receiver offset:
1.
2.
3.
4.
Calculating cable delay
The following formula can be used to calculate antenna cable delay:
D = ( L * C ) / V
Where:
D = Cable delay in nanoseconds
L = Cable length in feet
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3 VersaSync User Manual Rev. 6.0
Note: Once a survey has been initiated, the Survey Progress may not be
displayed right away until the receiver has completed its initialization pro-
cess.
Navigate to Interfaces > References: GNSS Reference
Click on the GEAR button next to the GNSS Reference. The GNSS 0 window will open:
Locate the Offset field, and enter the desired value.
Click Submit.
3.3 Managing References
on-time point by the Offset value to
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