Kongsberg M3 Sonar FLS, Installation Manual

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NMEA DBT
The NMEA DBT datagram provides the current depth under the transducer. In new
designs, this datagram format is frequently used to replace the DBK and DBS formats.
•
NMEA DPT
The NMEA DPT datagram provides the water depth relative to the transducer, and the
offset of the measuring transducer.
Processed data formats
The following processed data output formats are available.
•
.mmb
This is raw element data, not beamformed, in a 16-bit fixed-point complex format. This
format allows great flexibility in how the data is processed and allows you to do your
own beamforming or profile-point extraction. The data body size is determined by the
number of elements and the number of samples.
•
.imb
This format consists of beamformed data in a 32-bit floating point complex format. Data
body size is determined by the number of beams and samples. Different modes may
form a different number of beams. Therefore, data body size may change depending
upon the mode.
Synchronization
•
PRI Sync
PRI Sync (set with Trigger Mode on the
Sonar Setup
page of the
System Configuration
dialog box) provides ping synchronization with another Sonar Head or other acoustic
source that supports synchronization (for example, EK60, Sidescan, DVL, etc.). PRI
Sync is a level-sensitive method of synchronization. When the sync is held high, the
sonar will not transmit. The PRI Sync INPUT must be held low for 25μs in order to
trigger the Sonar Head. The Sonar Head will transmit a 100μs sync OUTPUT pulse when
configured as
Master
on the
Sonar Setup
page. The sync OUTPUT is generated each
time the Sonar Head transmits.
•
Host Time Sync Mode
Host mode synchronizes the Sonar Head time with the computer time. This mode is
critical for Bathymetry applications. Host mode only works if the computer is connected
to an accurate time source, such as a GPS or network time server. When connecting to
the Sonar Head, it takes two minutes to synchronize the time to within five milliseconds.
M3 Sonar FLS Installation Manual