Teledyne RD Instruments SENTINEL V REAL-TIME, Руководство по эксплуатации

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Sentinel V SC and RT Operation Manual
September
2017
EAR-Controlled Technology Subject to Restrictions Contained on the Cover Page.
Page 197
Expert Bottom Track Commands
This section lists the expert Bottom Track commands. Commands that start with the # sign are considered
“expert” commands.
#BB – Bottom Blank
Purpose Sets the blanking distance for Bottom Tracking.
Format #BBnnnnn
Range
nnnnn = 0 to 65535 cm
Default #BB0005
The default setting for this command is recommended for most applications.
Description #BB blanks out bad data close to the transducer head, thus creating a window that reduces
unwanted data in the ensemble. This allows the Sentinel V RT transmit circuits time to re-
cover before beginning the receive cycle.
#BH – Gain Switch Threshold
Purpose Sets the RSSI thresholds for switching the receiver gain for a bottom track ping.
Format #BH nnn, nnn (lo;hi)
Range
nnn = 0 to 255 counts
Default #BH 105,185
The default setting for this command is recommended for most applications.
Description Receiver gain control for bottom track always uses low gain when the altitude over the sea
bottom is less than the Gain Switch Altitude (set by the #BI command). When the altitude
is above the Gain Switch Altitude:
• Switch to high gain when RSSI is below the low threshold set by the #BH command.
•
Switch to low gain when RSSI is above the high threshold set by the #BH command.
Using two thresholds provides hysteresis, so that the gain does not need to switch on every ping when the
RSSI is at some in-between level.
#BI – Gain Switch Altitude
Purpose Selects the maximum vertical distance from the transducer to the bottom at which the Sen-
tinel V RT operates at low gain.
Format #BInnn
Range nnn = 0 to 999 meters
Default #BI005 (1000 kHz), #BI010 (500 kHz), #BI020 (300 kHz)
The default setting for this command is recommended for most applications.
Description When the vertical range to the bottom is less than #BI, the unit operates in low gain. When
the vertical range is greater than #BI, internal logic determines which gain (low or high) is