A 3.13nJ/sample energy-efficient speech extraction processor for robust speech recognition in mobile head-mounted display systems

An energy-efficient speech extraction (SE) processor is proposed for the robust speech recognition in the head-mounted display (HMD) systems. Speech extraction is essential for robust speech recognition in noisy environment. For the low-latency speech extraction, FastSE is proposed to overcome 50x larger complex cICA-based selection process which results in <;2ms SE latency. Moreover, a reinforced-FastSE (RFSE) scheme is proposed to achieve 97.2% accuracy with small on-chip memory size of only 33kB for the low-power HMD applications. Also, Reconfigurable matrix operation accelerator (RMAT) is implemented for energy-efficient acceleration of dominant matrix operation on SE. As a result, the proposed SE processor achieves 1.3x lower latency with 4.24x smaller memory compared to the state-of-the-art work, so that speech recognition in noisy environment becomes possible for mobile HMD applications.