Audio Device Crosstalk Cancellation Using Signal Segmentation

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Solution Overview

Problem

Conventional audio devices using speakers for virtual acoustic image localization suffer from sound quality deterioration, particularly with center-localized components and low frequency components, due to cross-talk cancellation processing that causes echoes and attenuates low frequencies.

Innovation Solution

An audio device is configured with signal processing means that extracts anti-phase and in-phase component signals using specific transfer characteristics to cancel crosstalk, and adds these signals in a manner that inverts or maintains their phases to eliminate crosstalk without degrading sound quality, using adders and signal processing sections to generate driving signals for speakers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If cross-talk cancellation processing is carried out using conventional methods, then crosstalk is suppressed and binaural signals are provided accurately to both ears, but sound quality deteriorates because center-localized components are perceived to be pulled back and low frequency components are weakened

Engineering Contradiction:
Improveaccuracy of binaural signal deliveryVSAvoidsound quality deterioration
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The audio signal is segmented into in-phase component signals and anti-phase component signals. The in-phase components (dominant in center-localized sounds and low frequencies) are processed separately from the anti-phase components. This segmentation allows selective processing where cross-talk cancellation is applied only to anti-phase components, while in-phase components are preserved, thereby maintaining sound quality while achieving accurate binaural signal delivery.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different processing qualities are applied to different components of the audio signal. The in-phase component signals are output without cross-talk cancellation processing to preserve sound quality, while the anti-phase component signals undergo cross-talk cancellation processing to eliminate crosstalk. This local differentiation of processing quality resolves the contradiction between crosstalk suppression and sound quality maintenance.

Inventive Principle:
Principle #3Local quality

2Reliability

If cross-talk cancellation processing is applied to eliminate crosstalk in speaker reproduction, then accurate binaural signals are provided to ears, but center-localized components and low frequency components are attenuated

Engineering Contradiction:
Improveaccuracy of acoustic image localizationVSAvoidlow frequency component intensity
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

The audio signal is divided into in-phase and anti-phase components. Since low frequency components are predominantly in-phase, they are extracted and output without cross-talk cancellation processing, preserving their intensity. Only the anti-phase components undergo cross-talk cancellation, ensuring accurate acoustic image localization while maintaining low frequency component intensity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Selective processing is applied where cross-talk cancellation is performed only on anti-phase components and not on in-phase components. This local quality differentiation ensures that low frequency components (which are mostly in-phase) are not attenuated, while still achieving reliable acoustic image localization through cross-talk cancellation of the anti-phase components.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP2178316B1Audio device
Publication Date: 2015.09.16 MITSUBISHI ELECTRIC CORP
  • EP2178316B1 patent drawingFigure 1
  • EP2178316B1 patent drawingFigure 2~3
  • EP2178316B1 patent drawingFigure 4

AI summary

A signal processing section 3 is set up which provides an anti-phase component signal S extracted by an anti-phase component extracting section 2 with a transfer characteristic (Hd + Hx) / (Hd - Hx); an adder 4 adds the phase-inverted signal of the anti-phase component signal S provided with the transfer characteristic by the signal processing section 3 and an in-phase component signal M extracted by an in-phase component extracting section 1; and an adder 5 adds the anti-phase component signal S provided with the transfer characteristic by the signal processing section 3 and the in-phase component signal M extracted by the in-phase component extracting section 1.