Design of acoustic metamaterials for integrated communication and sensing of small underwater unmanned platforms

The small-sized underwater unmanned platforms have limited underwater acoustic target direction of arrival (DOA) estimation capability due to size constraints which make array mounting difficult. This paper proposes a single hydrophone solution based on acoustic metamaterials by leveraging the characteristic that perforated plates exhibit distinct sound absorption properties with different dimensional parameters. An acoustic metamaterial shell with randomly varying dimensional parameters in all directions is designed. Frequency modulation of underwater acoustic signals from different directions is achieved by constructing frequency characteristics that differ with directions. On this basis, a communication-perception-integrated waveform is designed. An acoustic metamaterial-assisted single hydrophone DOA localization model is constructed. An underwater acoustic modulation and demodulation method is developed under the communication-perception-integrated framework. Pool experiments demonstrate that the designed acoustic metamaterial shell can realize single hydrophone DOA estimation and reliable underwater acoustic communication under this framework.