Acoustic Positioning System Beneath the Arctic Ice and Its Experimental Verification

Acoustic positioning and communication under the Arctic ice are important means to ensure the safety of underwater vehicles. This article presents an acoustic system designed to offer comprehensive positioning capabilities beneath the Arctic ice, describing the deployment outcomes in the Arctic region. The acoustic system consists of under-ice acoustic beacon, ice-based buoy, and shipborne unit. The under-ice acoustic beacon broadcasts acoustic signals, whereas the ice-based buoy detects these signals, receives Global Positioning System (GPS) information, and transmits parameters. The shipborne unit is responsible for receiving parameters and performing position calculation. Chi-square distribution preprocessing and the Kalman algorithm are used to achieve the effective filtering of time delay observations, resulting in improved positioning probability and accuracy. Meanwhile, the acoustic system has reserved the underwater acoustic communication interface, laying a foundation for the deep integration of positioning and communication in the future. As an experimental component of China's 13th Arctic scientific expedition, the positioning performance of the system was first verified, and four ice-based buoys and one fixed under-ice beacon were deployed along a baseline length of approximately 250 m. A continuous positioning test lasting 35 min was then conducted, successfully tracking the drift movement of the ice surface and verifying the performance of the system.