Jackson Labs RSR GNSS Transcoder, Руководство пользователя

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© 2017 Jackson Labs Technologies, Inc. 43
RSR GNSS Transcoder™ User Manual
STOPPING
The STOPPING and STARTING states only occur for 0.1 seconds each when transitioning to and
from RUNNING so they are unlikely but possible query responses. The RF output is disabled for all
states except for RUNNING and TRANSCODING. The RUNNING or TRANSCODING states are
indicated by the RF Active LED blinking at 10Hz. The three WAITING... states are states that occur
in the order listed before RUNNING in Transcoding or Auto simulation modes.
4.3.4 SIMulation:HOLDover:MODE
The simulation holdover mode controls the behavior when the external PVT reference indicates
position information is invalid while operating in Transcoding simulation mode.
The format of this command is:
SIMulation:HOLDover:MODE <OFF|ON|LIMIT>
When the LIMIT mode is selected, the limit time is specified with the SIM:HOLD:LIMIT command,
and the RF output is disabled when the unit reaches the specified holdover time limit described in
Section
4.3.6 . The SIM:HOLD:STATe? query responds with the current ON/OFF state of the
holdover.
4.3.5 SIMulation:HOLDover:STATe?
This command responds with the current ON/OFF state of holdover when operating in transcoding
simulation mode. The ON state indicates that the transcoding PVT is based on the local oscillator’s
holdover performance and/or the INS dead reckoning if operating in the INS simulation position
filter mode.
4.3.6 SIMulation:HOLDover:LIMIT
This command specifies the limit in seconds that the holdover state should remain active in the Limit
simulation holdover mode. The maximum limit is 1 day or 86400 seconds. Once this holdover limit
is reached the RF output will be disabled. For longer holdover periods, use the ON simulation
holdover mode.
The format of this command is:
SIMulation:HOLDover:LIMIT <int> [5,86400]
4.3.7 SIMulation:HOLDover:INDicate
This command selects the holdover indicate mode. The default mode is OFF and one of two holdover
indicate modes can be enabled. With the SV32 mode, the unit uses SV PRN 32 as a special satellite
to indicate holdover status to a users’ target GPS receiver. This mode encodes the holdover state in a
geostationary satellite with PRN 32 above the user’s position. With this holdover indicate mode
enabled, PRN 32 is present and can be tracked only when the unit is in a holdover state. The target
receiver can sense that PRN 32 is present and communicate the holdover state to the target system. A
missing PRN 32 indicates that the unit is running normally, and is not in holdover mode when the
PRN32 mode is selected. SV PRN 32 may or may not be present in the simulated RF output if the
INDICATE mode is set to OFF.