The Gnss Reference - Spectracom SecureSync User Reference Manual

3.6 OTHER Setup Pages
Table 3-7:
3.6.14

The GNSS Reference

When connected to a GNSS antenna that can receive a GNSS signal, SecureSync can use GNSS
as an input reference. The factory default configuration allows GNSS satellites to be
received/tracked with no additional user intervention required.
However, there are a few available user-configured settings for GNSS that allow a user to alter the
operation of SecureSync's built-in GNSS receiver. These settings include:
the ability to place the GNSS receiver in a mobile mode of operation (by default,
SecureSync is optimized to operate in a stationary environment)
the ability to apply an offset to account for antenna cable delays and other latencies, as
well as
the ability to erase the stored GNSS position information (latitude, longitude and antenna
height).
The Receiver Mode option allows the GNSS receiver to operate in either a stationary mode
(" Standard " or "Single Satellite" modes), or in a mobile mode environment (such as in an auto-
mobile, boat, airplane, etc.).
The available selections are:
3.6.14.1 Standard GNSS Receiver Mode
This mode should always be selected if SecureSync's GNSS receiver will remain stationary at all
times and will be able to track at last four satellites at all times. In this mode a GNSS survey , tak-
ing about 33 minutes, will initially be performed when at least four GNSS satellites become avail-
able. During the GNSS survey, the GNSS receiver must continuously track at least four satellites.
Otherwise the GNSS survey will have to start over.
Upon completion of the GNSS survey, SecureSync will go into time synchronization. Also, the
GNSS receiver will lock-in the calculated GNSS position and will enter the "Stationary" mode.
Once in Stationary mode, the GNSS survey will only be performed again if the equipment is then
relocated to another location (or if the GNSS location is manually cleared by a user). Upon a power
cycle, if the equipment has not been relocated, SecureSync will return to the Stationary mode
without the need to perform another GNSS survey.
In this mode, the GNSS receiver will be considered a valid input reference as long as a valid loc-
ation is entered (either automatically via the GNSS survey or manually entered by a user) and the
GNSS receiver continues to track at least four qualified satellites from that point forward.
3.6.14.2 Mobile GNSS Receiver Mode
This Mobile mode (also referred to as 'Continuous' mode) should only be selected if your
SecureSync unit will NOT remain stationary at all times, i.e. instead of the unit being operated in a
building, it is installed in a mobile platform (such as a vehicle, ship, plane, etc.). In this mode, no
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Signature control output-presence states
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3 SecureSync User Reference Guide Rev. 18