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arXiv · 2305.07896

Gradient Impedance Matching Layers Enable Broadband Water-Air Sound Transmission

Abstract

Efficient sound transmission across the water-air interface has always been expected in the field of ocean exploration. However, the existing researches are mainly concentrated on the narrow-band transmission based on resonance, which greatly limits the transmission capacity and efficiency. Here, we combined the air-based and water-based metafluids to realize an exponential gradient impedance matching layer for broadband water-air sound transmission. By cooperatively adjusting the sound velocity and thickness in the matching layers, we modulated the required acoustic parameters of each layer into a reasonable range, which can be conveniently achieved by the proposed metafluids. A matching layer sample was constructed and validated in a water tank. Experimental results show that the proposed matching layer can achieve an average sound energy transmission enhancement above 16.7dB from 880Hz to 1760Hz across the water-air interface. Moreover, we use the proposed matching layer to demonstrate a multicolor picture transmission from air to water, which shows extremely high communication capacity and accuracy. Our work is promising for more applications based on water-air transmission and opens a new avenue to the design and implementation of the extreme impedance matching case.

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Ping Zhou, Han Jia, Yafeng Bi, Yunhan Yang, Yuzhen Yang, Peng Zhang, Jun Yang. 2023-05-13. Gradient Impedance Matching Layers Enable Broadband Water-Air Sound Transmission. https://arxiv.org/abs/2305.07896

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