Transmission of Video Image in Underwater Acoustic Communication

TL;DR

This paper demonstrates a real-time underwater acoustic communication system that transmits video images by multiplexing orbital angular momentum beams, significantly enhancing data capacity over traditional methods.

Contribution

The authors develop and showcase a novel underwater acoustic communication system using multiplexed orbital angular momentum beams for high-capacity video transmission.

Findings

Achieved spectral efficiency of 8 (bit/s)/Hz.

Successfully multiplexed eight orbital angular momentum charges.

Demonstrated potential for increased underwater communication capacity.

Abstract

Acoustic communication is currently considered as the best way to transmit information over long distances under water, since acoustic waves have lower attenuation in water than the other information transmission media. However, current information transmission rates of the underwater acoustic communication is usually limited by low-frequency bandwidth due to the large attenuation which characterized in high-frequency sound waves in water. Spiral acoustic beams with helical wavefront dislocations carrying orbital angular momentum have been applied to acoustic levitation and capture. Recently, harnessing the orthogonality and the infinite dimension of Hilbert space in underwater acoustic communication has been considered promising. Here, we construct a real-time underwater acoustic communication system to transmit video image. The system multiplexes eight orbital angular momentum topology charges ranging from +1 to +8 and encoded with on-off keying modulation format, achieving a spectral efficiency of 8 (bit/s)/Hz. This demonstration suggests that multiplexed information-carrying orbital angular momentum acoustic beams presents tremendous potential for increasing the capacity of underwater communication systems.