An Energy-Efficient Kalman Filter Architecture with Tunable Accuracy for Brain-Computer Interfaces

Kalman Filter (KF) is the most prominent algorithm to predict motion from measurements of brain activity. However, little effort has been made to specialize KF hardware for the unique requirements of embedded brain-computer interfaces (BCIs). For this reason, we present the first configurable KF hardware architecture that enables fine-grained tuning of latency and accuracy, thereby facilitating specialization for neural data processing in BCI applications and supporting design-space exploration. Based on our architecture, we design KF hardware accelerators and integrate them into a heterogeneous system-on-chip (SoC). Through FPGA-based experiments, we demonstrate an energy-efficiency improvement of $15.3 x$ and $10^{3} x$ better accuracy compared to state-of-the-art implementations.