公开(公告)号：US09607626B1

公开(公告)日：2017-03-28

申请号：US15082684

申请日：2016-03-28

Applicant: Amazon Technologies, Inc.

Inventor： Jun Yang ,  Colin Randall McEnroe ,  Jian Guo

IPC: H03G5/00 ,  G10L19/26 ,  G10K11/178

CPC classification number: G10L21/0208 ,  G10L2021/02082

Abstract: A reconfigurable filter bank system that has an asymmetrical tree structure with multiple stages to generate multiband outputs. Each stage may include cascaded low-pass filters (LPFs), cascaded high-pass filters (HPFs) and/or all-pass filter(s) (APF(s)) having identical phase responses. As the cascaded LPFs, cascaded HPFs and APF(s) have identical phase responses, each frequency band of the multiband output may have an identical phase shift such that the frequency bands are in-phase and can be added together. The multiband outputs of the reconfigurable filter bank may have near-perfect reconstruction (e.g., small number of cross-band ripples) and therefore only minor distortion. In addition, the number of frequency bands and corresponding non-uniform bandwidths (e.g., frequency ranges) may be user-adjustable and/or reconfigurable during device operation. Further, the reconfigurable filter bank may have reduced computational complexity and/or latency.