Cymbal Acoustic Protocol - Kongsberg HiPAP 501 Instruction Manual

HiPAP® Model 501/451/351/101
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Cymbal acoustic protocol

Cymbal is the new acoustic protocol used for both positioning of
subsea transponder in SSBL/LBL mode and data
communication to and from transponders.
The technology
Cymbal utilizes Direct Sequence Spread Spectrum (DSSS)
signals for positioning and data communication. The data
communication speed is variable and can be adapted to the
acoustic communication conditions; noise and multi-path.
DSSS is a wide band signal.
The Cymbal protocol provides new characteristics for both
positioning and data communication.
Range capability and reduced impact from noise
Cymbal protocol can transmit more energy in each positioning
pulse. Compared to the current HiPAP® 500 this extra energy
will provide higher position accuracy at low signal to noise
ratio. It will also provide longer range capabilities. This
improvement in energy is 5dB.
Range accuracy
The Cymbal signal gives range accuracy in the order of 0.01m,
error contribution from sound velocity and ray bending not
included.
Directional measurements
In SSBL operation, the accuracy of directional measurement is
the main contributor to the position accuracy. The HiPAP® 501
has new and improved algorithms for directional computation
when using Cymbal. At low signal to noise ratio the system will
be more robust.
Number of channels
The Cymbal protocol has increased number of unique codes for
transponder channels compared to the current system. At present
there are 50 unique transponder channels.
Multi-path capability
The Cymbal protocol is designed to have good multi path
properties. The processing technique allows signals to and from
the transponder to overlap and still be able to have a correct
detection.
Power management – lifetime
303490/H