Energy Harvesting from Underwater Acoustic Signals: An Exploration
Underwater acoustic transceivers are ubiquitous in marine sensing and communication systems, and every transceiver that transmits or picks up a signal is, in effect, also converting acoustic energy into an electrical one. This raises a natural question: could some of that energy be harvested and put to use, rather than dissipated? This talk presents ongoing work exploring that question in the wider context of a structured system approach, using piezoelectric transducers and their electronic interface as the entry point into the problem.
We discuss circuit topologies for rectifying a transducer’s AC output into usable DC power, comparing standard rectifier structures and their limitations. To better understand and predict system behavior, we develop an equivalent-circuit representation of transducers that captures the conversion of incident acoustic energy into electrical signals, providing a framework for reasoning about harvester performance across different operating conditions.
Realistic acoustic excitation poses several open challenges, including low open-circuit voltages, limited usable bandwidth, and variability in signal strength and frequency content. We discuss a range of strategies for approaching these challenges, touching on circuit-level techniques, transducer design considerations, and system-level approaches, along with the trade-offs each involves.