
April
2018
Pathfinder DVL Guide
Page 200
EAR-Controlled Technology Subject to Restrictions Contained on the Cover Page.
This data type is output when selecting
PD0
and the Precision Navigation feature is installed.
Table 45.
Navigation Parameters Data Format
Hex Digit Binary
Byte
Field
Description
1-4
1, 2
ID_NAV_PARAMS /
Navigation Parameters
ID
Stores the navigation parameters identification word,
ID_NAV_PARAMS, defined as 0x2013
5-36
3-18
TIME-TO-BOTTOM
BEAMS 1-4
Stores
T
bot
, the time interval between the hardware trigger (de-
fined by the CX command) and the center time, or “time the
ping hits the bottom,” of the bottom track measurement for
Beams 1-4. Unit is 8 carrier cycles (52.08
µ
s for 153.6 kHz). Un-
signed integer.
37-52
19-26
BOTTOM TRACK STD
DEVIATION BEAMS 1-4
Stores a prediction of the single ping bottom-track standard de-
viation calculated with the velocity variance model. Units are
mm/sec.
53
27
SHALLOW OPERATION
FLAG
Stores the flag indicating whether the Pathfinder is operating in
shallow mode or not. If this value is set to 1, then the Pathfinder
is operating in shallow mode with one beam pinging at a time. If
this value is 0, then the Pathfinder is operating in Deep Mode
with all beams pinging at the same time.
54-86
28-43
TIME-TO-WATER MASS
BEAMS 1-4
Stores
T
wm
, the time interval between the hardware trigger (de-
fined by the CX command) and the center time, or “time the
ping hits the center of the water mass layer,” of the water mass
measurement for Beams 1-4. Unit is 8 carrier cycles (52.08
µ
s for
153.6 kHz). Unsigned integer.
87-90
44-45
RANGE TO WATER
MASS CELL
The range to the water mass cell being tracked. Units are in car-
rier cycles (6.51
µ
s for 153.6 kHz).
91-106
46-53
WATER TRACK STD
DEVIATION BEAMS 1-4
Stores a prediction of the single ping water-track standard devi-
ation calculated with the velocity variance model. Units are
mm/sec.
107-138
54-69
BOTTOM TRACK TIME-
OF-VALIDITY
BEAMS 1-4
When CX=1, stores the time interval between the center time,
or “time the ping hits the bottom”, and the time the Trigger was
received by the DVL for the Bottom Track ping transmission.
When CX=0 (i.e. trigger disabled), stores time elapsed between
the center and the first character in the PD0 sentence.
Unit is 1µsec. Accuracy is within ± 5msec. Unsigned integer.
Note the value will be set to zero if the bottom track velocity for
the corresponding beam is bad.