Poster: Energy efficiency maximization for underwater acoustic backscatter communications

Backscatter communication enables battery-less IoT devices by modulating ambient electromagnetic waves (terrestrial) or acoustic (underwater) waves without active transmission. This paper presents an energy-efficient design framework for underwater acoustic backscatter systems, where high-power transceivers emit acoustic signals and piezoelectric nodes modulate and reflect them back. Our work establishes a comprehensive analytical model that integrates three critical aspects: the electromechanical behavior of piezoelectric nodes, the underwater acoustic channel, and transceiver placement. Leveraging a circuit-theoretic approach to piezoelectric behavior, this framework enables the systematic optimization of key material and communication parameters, including vibration mode selection, circuit loading, and modulation scheme, to maximize energy efficiency. Simulation results validate the effectiveness of the proposed models and optimization strategies, and identify the dominant parameters that govern system energy efficiency.