A Low-Power, High-Linearity Filter Bank for Auditory Signal Processing Microsystem

We present an implementation of an auditory filter bank that decomposes the input signal into 16 parallel bands with central band frequencies ranging from 150 Hz to 10 kHz according to the mel-scale. The proposed integration of the designed filter bank in a microsystem for acoustic source separation poses a stringent constraints on the linearity and dynamic range of the filters. The capacitive attenuation is used to increase the voltage range at the input and the output of the filter. The simulation results demonstrate that the third order harmonic distortion of the bandpass filter with the central frequency of 150Hz is -59.6dB and dynamic range is 59.9dB. The power consumption of the filter bank implemented in 0.5 mu m CMOS technology is 36 mu W.