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The network was operative with fixed and mobile nodes. Via the MOOS middleware, the Command and Control center was able to control the system, including sending commands to AUVs and requesting high rate sensor data. MOOS was operated in secure mode. Point to point connections were of varying quality due to environmental variation. Hence multihop routing proved useful.

Command and ControlSignal received on the vertical arrayFolaga deployment from Research vessel Gunnerus

The additional spare modem was deployed to replace Fixed Node 1. Full network was established, including Command and Control (C2). The Folaga was deployed from Research Vessel Gunnerus and followed by HiPAP acoustic positioning system. Gunnerus also served as an artificial AUV, with a cabled transducer at 20 m depth. In this way command and response exchange with the C2 could be followed in detail.

Network layout Folaga deployed from RV Gunnerus

Folagas at sea, diving. Relatively rough weather. A fixed node was lost during recovery. Will be replaced by a spare KM modem.

FolagaInWaves.JPG: Folaga at sea

Fixed nodes with temperature sensor chains were deployed. All network layers, from the physical acustic links via IP to the MOOS database were established.   A little wind and waves.Fixed node deployment: Subsurface float being attached

Last node completed Following a Folaga

The Subsurface Telemetry Unit, with its vertical hydrophone array and fiberoptical cable to shore is installed and working. Acoustical connectivity tests have been completed. Folagas were at sea.

Optical cable being deployed Subsurface Telemetry Unit with Kongsberg modem (yellow) on its way down

Engineering tests are underway. After some delays caused by the transportation companies, all subsystems are being set up and functions verified.

Weather conditions are fair.

STU assembly on pierFolaga first wet-testC2 screen early snapshot

RV Leonardo outside Pianosa IslandSubsurface Telemetry Unit redeploymentPoint to Point transmissions, received signalsAfter some maintenance to the Subsurface Telemetry Unit and attached vertical array it was successfully redeployed this morning. The weather was calm after a windy weekend. Point to point measuremens are currently being performed by transmitting signals from the R/V Leonardo and receiving on the vertical hydrophone array.

Folaga deployment from RHIBFolagas with modemKM modem on FologaFolaga AUVs where deployed today from a RHIB in parallel an underwater acoustic communication link was established between the Folagas and the master modem deployed from the R/V Leonardo. Various geometries where tested including fixed stations at the surface, the Folagas moving on the surface, Folagas deployed at various depths in a stationary position and a underwater moving scenario.

FolagasFolagas and KM modemsFolagas in PortRV LeonardoLab workDuring these days signals were transmitted from the RHIB and pier location, various resources both equipment and personnel can be seen in the pictures.

Weather conditions did not permit the safe operation at sea nevertheless signal transmissions where performed from the pier using the Portable Acoustic Source Unit (PASU) and reception on the Subsurface Telemetry Unit (STU) 16 hydrophone vertical array. Initial results can be seen below.demodulated BPSK constellation