Acoustic Processing Device for Multichannel Nonlinear Acoustic Echo Cancellation

Simple SummaryContent extracted from patent full text and abstract with AI.

This invention relates to an acoustic processing device specifically designed for multichannel (MIMO) nonlinear acoustic echo cancellation (AEC). The system preprocesses multiple loudspeaker signals using filters based on adjustable combinations of mathematical basis functions (like polynomials or neural networks) to better model and predict the nonlinear distortions that occur in loudspeakers and amplifiers. It uses these preprocessed signals with advanced adaptive filtering algorithms to estimate and subtract echo from each microphone’s input, resulting in clear, echo-reduced microphone signals even in challenging environments with multiple speakers and microphones.

Use CasesContent extracted from patent full text and abstract with AI.

• Smart speakers with multiple microphones and loudspeakers for improved voice assistant performance.
• Hands-free teleconferencing systems (e.g., conference phones or meeting room systems) where multiple users speak and listen concurrently.
• Automotive infotainment systems for in-car voice control and communication.
• Consumer and professional audio devices that require echo-free communication, such as hearing aids or augmented audio headsets.
• Telepresence robots or remote collaboration tools that utilize spatial audio and multiple sound sources and sensors.

BenefitsContent extracted from patent full text and abstract with AI.

• Significantly better echo cancellation even when nonlinear distortions are present (such as those generated by small, power-efficient loudspeakers).
• Maintains high quality of the near-end user’s speech and audio even during full-duplex (simultaneous talk/listen) operation.
• Highly scalable—works efficiently with many speakers and microphones, allowing tradeoffs between audio quality and computational resources.
• Allows use of prior knowledge about the spatial arrangement of microphones and speakers to further improve performance.
• Computational efficiency superior to purely linear approaches or high-dimensional models, suitable for use in miniaturized or portable devices.
• No audible degradation even when nonlinearities are not active, so always safe to deploy.
• Adaptive—can adjust in real time to changing device layouts, audio environments, or operating conditions.

Technical Classifications (CPCs)

Inventors & Applicants

Patent Abstract

An acoustic processing device (110) for multichannel nonlinear acoustic echo cancellation is disclosed. The acoustic processing device (110) comprises a processing circuitry (120) configured to apply to each of a plurality of loudspeaker signals a respective pre- processing filter for filtering each loudspeaker signal in order to obtain a respective pre-processed loudspeaker signal, wherein each pre-processing filter is based on a linear combination of a plurality of pre-defined basis functions, wherein each of the pre-defined basis functions is weighted by an adjustable pre-processing weighting coefficient. The processing circuitry (120) is further adapted to enable echo reduction by determining for each of a plurality of microphone signals an estimated echo signal on the basis of the plurality of pre-processed loudspeaker signals and determining a respective echo reduced microphone signal based on the respective microphone signal and the estimated echo signal.