Title :
Auditory feature extraction using self-timed, continuous-time discrete-signal processing circuits
Author :
Kumar, Nagendra ; Cauwenberghs, Gert ; Andreou, Andreas G.
Author_Institution :
Dept. of Electr. & Comput. Eng., Johns Hopkins Univ., Baltimore, MD, USA
fDate :
9/1/1997 12:00:00 AM
Abstract :
A compact integrated subsystem for accurate real-time measurement of level crossing time-intervals, suitable for multiresolution feature extraction from an analog cochlear filter bank is presented. The subsystem is inspired by the function of the inner hair cells in the mammalian cochlea and is based on continuous time discrete-signal processing circuits. Experimental results from a fabricated array of nine elements demonstrate instantaneous frequency-to-voltage conversion over a range covering the audio band. The power consumption is less than 20 μW per cell from a 5 V supply, when the system is biased to operate over the speech frequency range
Keywords :
CMOS integrated circuits; VLSI; arrays; continuous time systems; ear; feature extraction; hearing; mixed analogue-digital integrated circuits; real-time systems; speech recognition; time measurement; voltage-frequency convertors; 20 muW; 5 V; ASIC; analog cochlear filter bank; array; audio band; auditory feature extraction; compact integrated subsystem; continuous time discrete-signal processing circuits; frequency-to-voltage conversion; level crossing time-intervals; mammalian cochlea; multiresolution feature extraction; power consumption; real-time measurement; speech frequency range; Algorithm design and analysis; Circuits; Clocks; Feature extraction; Frequency; Hardware; Signal processing; Signal processing algorithms; Signal representations; Very large scale integration;
Journal_Title :
Circuits and Systems II: Analog and Digital Signal Processing, IEEE Transactions on