On board Polarstern there are three different antennas available, which can be used alternatively but not at the same time. First antenna is flush and permanently mounted in ships keel at ca 11m depth. The antenna is protected by window, which can be opened during operation. Second antenna named deployable antenna is lowered through the moon pool. Third antenna from Thomson Marconi is fixed mounted at a device carrier for moon pool. Active antenna is connected to electronic device named USBL-Box in room E-525a. The control and operation of the system is performed via web-Interface.
For Posidonia system are two transponders of type Oceano ET861 and two releasers of type Oceano RT 861 B1S (RT2500 S-Side Bar) on board available. The maximum depth amounts to 6000m.
System IXSEA TT801 (SN 002) can alternatively be used to send release commands.
Online data stream of Posidonia is broadcasted via UDP, which can be used by alternative visualisation tools (e.g. PosiView) or for seperately logging. | 
