Real-Time Current Mapping Using Time-Reversal Coastal Acoustic Tomography: Theoretical Framework and Hardware Validation

This paper introduces a Time-Reversal Coastal Acoustic Tomography (TR-CAT) system designed for real-time mapping of coastal currents. Using time-reversal techniques, the system overcomes the limitations of traditional Ocean Acoustic Tomography (OAT), eliminating the need for reciprocal transmissions and instrument retrieval. This innovation simplifies the process of estimating differential travel times (DTTs), which are crucial for current measurements. The functionality of the TR-CAT system was validated through water tank experiments, which confirmed the accuracy of its hardware and signal processing methods in a controlled environment. Simulations showed strong alignment with theoretical predictions for DTT estimation, further demonstrating the system's reliability. Field experiments are planned to evaluate the system's performance in more complex ocean environments. The TR-CAT system represents a step forward in enhancing the efficiency of real-time ocean current monitoring.