
Pathfinder DVL Guide
April
2018
EAR-Controlled Technology Subject to Restrictions Contained on the Cover Page.
Page 195
This format is selected via the #BJ command (see
Table 44:
Bottom Track Range Output Data Format
Binary Bytes
Field
Description
1-2
ID
PD0 ID (MSB=58h LSB=04h)
3-6
Slant Range
Average range to bottom along the Z axis of the instrument frame, aver-
aged over the ensemble. Valid only for at least 2 beams good on axis; zero
is output for invalid data. Units are 0.1mm.
7-10
Axis Delta
Range
Difference in slant range between beam 1 & 2 estimate and beam 3 & 4
estimate averaged over the ensemble. Valid only for 4 beam good pings.
Units are 0.1mm.
11-14
Vertical Range Average vertical range (altitude) of bottom depth (accounting for instru-
ment tilt) over the ensemble. Zero is output if vertical range cannot be cal-
culated because less than three beams are good, etc. Units are 0.1mm.
15
% Good 4 Bm
Percent Good 2 axis (4 Bm) slant range solutions.
16
% Good Bm
1&2
Percent Good axis Bm 1 & 2 slant range solutions.
17
% Good Bm 3
& 4
Percent Good axis Bm 3 & 4 slant range solutions.
18-21
BM 1 Raw
Range
Slant range to the bottom along beam 1 multiplied by cos(Janus), averaged
over the ensemble, even if fewer than 3 beams detect the bottom. Units
0.1mm
22-25
BM 2 Raw
Range
Slant range to the bottom along beam 2 multiplied by cos(Janus), averaged
over the ensemble, even if fewer than 3 beams detect the bottom. Units
0.1mm
26-29
BM 3 Raw
Range
Slant range to the bottom along beam 3 multiplied by cos(Janus), averaged
over the ensemble, even if fewer than 3 beams detect the bottom. Units
0.1mm
30-33
BM 4 Raw
Range
Slant range to the bottom along beam [n] multiplied by cos(Janus), aver-
aged over the ensemble, even if fewer than 3 beams detect the bottom.
Units 0.1mm
34
BM 1 Raw
Max BT Filter
Maximum Bottom detection filter output in counts averaged over the en-
semble for beam 1 even if less than 3 beams detecting bottom.
35
BM 2 Raw
Max BT Filter
Maximum Bottom detection filter output in counts averaged over the en-
semble for beam 2 even if less than 3 beams detecting bottom.
36
BM 3 Raw
Max BT Filter
Maximum Bottom detection filter output in counts averaged over the en-
semble for beam 3 even if less than 3 beams detecting bottom.
37
BM 4 Raw
Max BT Filter
Maximum Bottom detection filter output in counts averaged over the en-
semble for beam 4 even if less than 3 beams detecting bottom.
38
BM 1 Raw
Max BT Amp
Bottom amplitude at measured range in counts, averaged over the ensem-
ble, for beam 1 even if fewer than 3 beams detect the bottom.
Amplitude
value corresponds to the middle of the bottom return.