An Omni-directional Underwater Acoustic Modem Based on Cortex-M3

As the need for underwater wireless sensor network increases recently, there has been an increased demand for a compact and low-power consuming communication device. In this paper, we design and implement an omni directional underwater acoustic modem with on-board cortex-M3 and verify it in various environments. In a water tank experiment, it is verified that the modem can achieve error-free communication at distance of 200 cm with data rate of 0.2 kbps. In addition, from a pond experiment, we also has proven that the modem communicates at 40 m with 0.2 kbps and 3.3·10^-4 of BER. From these observations, it might be utilized for the wide applications based on underwater acoustic communication.