A Dual-Stage, Ultra-Low-Power Acoustic Event Detection System

A dual-stage, ultra-low power (ULP) acoustic event detection (AED) system is presented. The proposed system consists of two stages, the always-on stage with ultra-low power serialized (ULPS) feature extraction, and the high performance stage based on long-term speech diversion (LTSD). The dual stage approach achieves ultra-low power consumption without significantly degrading system performance. A hardware-efficient ULP AED system architecture is discussed, and system performance evaluation is provided in details. The proposed system can achieve > 95% detection rate with 0.2% false alarm rate for voice activity detection (VAD) and 97% detection rate with 1% false alarm rate for AED while its estimated power consumption is in a nano-Watts range. By controlling the duty cycle ratio between two stages, the proposed system enables graceful tradeoff in system performance and power consumption.