Experimental Validation of a Long-Range Underwater Acoustic Communication Method in the Sea of Japan

This study is focused on development and experimental validation of an ultra-long-range hydroacoustic communication method capable of data transmission over a distance exceeding 1000 km in the challenging acoustic environment of the Russian coastal seas. The proposed method employs frequency manipulation with tonal pulses in a narrow low-frequency band (300–500 Hz), ensuring robustness against multipath propagation, intersymbol interference, and Doppler distortions. A key feature of this method is the use of signal frames containing synchronization M-sequences and information components processed via the Goertzel algorithm for dominant frequency detection. Experimental verification in the Sea of Japan made it possible to achieve the record-breaking message transmission over 1073 km with a signal-to-noise ratio near 0 dB, demonstrating just 1–3% decoding error probability at 4 bit/s. The study results confirm the feasibility of developing the information support system for underwater vehicles across the entire Russian economic zone, with strategic implications for marine reconnaissance, navigation, and monitoring. This method enables the covert one-way communication with autonomous underwater vehicles, including long-range gliders.