Specifications

BATS AND PORTABLE BATS OPERATION
3-105
3.7.2.12 RS-232 PARAMETER DESCRIPTION
These are the descriptions of the parameters used in the Format Sentences above unless otherwise
listed.
The TARGET NUMBER (#) represents the various target symbols and can range from 0 to 9. The
zero is output when in the self-test mode to indicate that the RS-232 data is simulated.
The TIME (TOD) is output at the beginning of each target's data. It is synchronous with the 24-
hour time on the screen of the Trackman PC. It is equal to the time that the Trackman PC received
the acoustic reply. When synchronized with the GPS clock the accuracy of the time as output is
within 50 milliseconds of the actual time of reply.
The HEADING (HDG) is only displayed when a compass interface is used. The HEADING can either
be the Magnetic heading of the vessel or the True heading, if the NMEA heading data has been de-
termined to be corrected for True North. The NMEA ORE output sentence shows an identifier in the
string to show whether data is Magnetic (M), True (T) or from an Analog source (A). The heading is
also displayed on the Status Display of the Trackman PC’s screen.
The BEARING (BRG) output in degrees is a relative bearing from the ship to the target. When the
compass interface is in use, and the SYSTEM / COMPASS / RS232 TGT DATA is set to North Ref.,
the target bearing is referenced to North. The target bearing is corrected for the entered hydro-
phone offsets (target is referenced to the pitch roll center of the vessel) or if Antenna Offsets are
entered it is corrected again to the Antenna offset point. The SYSTEM / COMPASS / RS232 TGT
DATA switch can be set to either NORTH REF or BOW REF. See section 3.4.2.
The DEPRESSION ANGLE output on REV4 formats is the depression angle calculated from the fi-
nal horizontal distance and the depth (either input or calculated depth). The depression angle out-
put on the NUWC formats is the angle as measured by the hydrophone’s three elements but it has
been corrected for pitch and roll motion. It is not compensated by the hydrophone X,Y,Z deviation,
caused by the offset between hydrophone and vessel pitch / roll center. (I.e., the arc that the hy-
drophone swings through during vessel motion.) System takes wherever the hydrophone was when
the reply was received and reconverts depression angle based on a gravity level measurement at
that position.
The SLANT RANGE (S.R.) is the measured travel time between the hydrophone and the tran-
sponder. It is output in meters, feet or yards, depending on RS-232 UNITS selection. The Slant
Range is the actual measured slant range to the transponder or responder. In transponder or re-
sponder mode no hydrophone offsets are applied to the data. If in Pinger mode it is a calculated
value with offsets applied if applicable. (See NOTE below.)
The X and Y position are the coordinates from the ship to the target. They are output in meters,
feet or yards if STANDARD, STANDARD-EC, STD W/PR, STD-EC W/PR, NCSC or NMEA ORE is se-
lected, or just meters if Format REV 4 or REV 4-EC is selected. If NMEA TTM is selected then the X
and Y ranges are in kilometers.