• acoustic
• network
• sintef
• uan
• uan11
• underwater

This thesis aims at analysing some of the many data collected during the final sea trial of the UAN11 project (Underwater Acoustic Network) in the Trondheim fjord, Norway. The objective is to check how conditions of the underwater acoustic channel affected communications, namely ping sequences, between specific nodes and, in those periods of time when good conditions were associated with bad communication results, try to find the reason why. The available ping results were fetched and used to identify periods of time with good or bad communications between the master node and other fixed or mobile nodes: such results were compared with the channel impulse responses stored, record by record, in the acoustic modems logfiles. Whenever ping results and channel conditions did not match, the upper communications levels (UANtun and MOOS) were analysed to try and find at which point the system failed. The matching was generally positive, but sometimes a favourable acoustic channel delivered bad ping results: a deeper analysis showed that apparently a traffic overload of the UANtun level was the cause for lost pings.