System and method for clock synchronization of acoustic echo canceller (AEC) with different sampling clocks for speakers and microphones

Patent metadata

Field	Value
Publication number	US-9025762-B2
Application number	US-201213657908-A
Country	US
Kind code	B2
Filing date	Oct 23, 2012
Priority date	Oct 23, 2012
Publication date	May 5, 2015
Grant date	May 5, 2015

Abstract

Clock synchronization for an acoustic echo canceller (AEC) with a speaker and a microphone connected over a digital link may be provided. A clock difference may be estimated by analyzing the speaker signal and the microphone signal in the digital domain. The clock synchronization may be combined in both hardware and software. This synchronization may be performed in two stages, first with coarse synchronization in hardware, then fine synchronization in software with, for example, a re-sampler.

First claim

What is claimed is:

1. A method comprising:
determining, by an acoustic echo canceller, a coarse frequency difference between a first clock and a second clock, wherein determining the coarse frequency difference comprises measuring a phase rotation between a first signal associated with the first clock and a second signal associated with the second clock at a predetermined frequency component;
performing, by said acoustic echo canceller, a coarse frequency adjustment of at least…

Assignees

• Cisco Tech Inc

Inventors

• Bao Feng
• Mauchly J William
• Kunapuli Subrahmanyam
• Bao Xiangyu

Classifications

• H04R1/2869 Primary

  Electricity · mapped topic

• H04M9/082 Primary

  Electricity · mapped topic