Real-time Implementation of Auditory Gammatone Filter Bank with FPGA

Gammatone Filter Bank (GTFB) is perfectly suitable for speech processing systems like digital hearing aids, speech enhancement and speech recognition system. However, the high computational complexity and non-real-time characteristic in the hardware synthesis restrict its practical application. In this paper, an efficient core computation unit structure is proposed. Besides, a low complexity synthesis algorithm is proposed and the real-time characteristic is achieved by compensating the filter delay. The measurement results verified show that a 128-band high-efficient real-time reconfigurable Gammatone Filter Bank is realized in FPGA. The design has only 20 ms delay and improve the dual-microphone CASA speech enhancement system performance.