Real-Time CARFAC Cochlea Model Acceleration on FPGA for Underwater Acoustic Sensing Systems

This paper presents a real-time, energy-efficient embedded system implementing an array of a Cascade of Asymmetric Resonators with Fast-Acting Compression (CARFAC) cochlea models for underwater sound analysis. Built on the AMD Kria KV260 System-on-Module (SoM), the system integrates a Rust-based software framework on the processor for real-time interfacing and synchronisation with multiple hydrophone inputs, and a hardware-accelerated implementation of the CARFAC models on a Field-Programmable Gate Array (FPGA) for real-time sound preprocessing. Compared to prior work, the CARFAC accelerator achieves improved scalability and processing speed while reducing resource usage through optimised time-multiplexing, pipelined design, and elimination of costly division circuits. Experimental results demonstrate 13.5% hardware utilisation for a single CARFAC instance and a whole board power consumption of 3.11 W when processing a 256 kHz input signal in real time.