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Acoustic communications under shallow shore-fast Arctic Ice

The Arctic Ocean is ringed by shallow areas along the continental shelves which are home to shore-fast ice throughout much of the winter. These areas are being used for both traditional activities such as fishing and hunting, and increasingly, at least in some locations, resource extraction and related exploration. Environmental monitoring under shore-fast ice in multi-use regions will increasingly be accomplished using autonomous underwater vehicles and non-cabled sensors, both of which will require means for acoustic data telemetry. In this paper the results of an experiment done to test the data rate, range and reliability of acoustic communications in 5–10 m deep water under shore-fast ice near Prudhoe Bay, Alaska are described. The experiment was carried out in late winter of 2014 using Micro-Modem communications equipment operating at 10 kHz at ranges of 1.5 to 5.6 km and data rates (burst) from 80 to 5000 bps. The achievable data rates were dependent on range and water depth, plus the presence of ice keels that blocked the acoustic path in some areas. The feasibility of long baseline (LBL) navigation at these ranges is also confirmed by the results.