Voice activity detection system and acoustic feature extraction circuit thereof
AssigneesNCKU Research and Development Foundation, Himax Technologies Limited
InventorsMeng-Ju Chiang, Soon-Jyh Chang
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Abstract
An acoustic feature extraction (AFE) circuit includes a plurality of band-pass filters (BPFs) adaptable to a plurality of channels with different band-pass frequency ranges respectively for switchably receiving an amplified signal, thereby generating corresponding filtered signals, the plurality of BPFs including an operational amplifier that is shared among the plurality of channels; and a rectifier switchably coupled to receive the filtered signals, thereby generating a rectified signal. The amplified signal is time-division demultiplexed onto the BPFs in different phases, and the filtered signals are time-division multiplexed onto the rectifier in different phases.
Claims5
A voice activity detection (VAD) system, comprising:
- an amplifier coupled to receive a sound signal, according to which an amplified signal is generated;
- an acoustic feature extraction (AFE) circuit coupled to receive the amplified signal, and configured to generate a feature signal representing a feature extracted from the amplified signal;
- a classifier configured to identify the feature signal as a voice or a noise;
- wherein the AFE circuit comprises a single operational amplifier that is shared among a plurality of channels;
- a plurality of band pass filters (BPFs) adaptable to the plurality of channels with different band-pass frequency ranges respectively for switchably receiving the amplified signal, thereby generating corresponding filtered signals;
- and a rectifier switchably coupled to receive the filtered signals, thereby generating a rectified signal;
- wherein the amplified signal is time-division demultiplexed onto the BPFs in different phases, and the filtered signals are time-division multiplexed onto the rectifier in different phases.
Dependencies are inferred from the claim text.