Acoustic Crosstalk Cancellation for Compact Audio Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Compact audio playback devices, such as smartphones and tablets, struggle to provide effective stereo perception due to the close placement of their speakers, leading to significant acoustic crosstalk and reduced stereo effect, with existing solutions either requiring external speakers or complex processing that increases processor and memory demands.
Innovation Solution
A method and device for determining an acoustic crosstalk canceller that involves calculating a transfer function of the stereo playback path, inverting it, and applying frequency-dependent regularization parameters to create a crosstalk canceller, which reduces crosstalk without the need for band branching, allowing for effective stereo playback on compact devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If speakers are placed close together in compact devices, then device size is reduced, but acoustic crosstalk increases and stereo perception deteriorates
Solution Approach 1:
The patent applies preliminary anti-action by pre-processing the audio signals to cancel acoustic crosstalk before playback. The system calculates transfer functions representing the acoustic paths from speakers to ears, then applies inverse filtering to pre-compensate for the crosstalk that will occur during playback, thereby eliminating the harmful effect while maintaining compact speaker placement
Solution Approach 2:
The patent changes parameters by applying frequency-dependent regularization parameters to the transfer function inversion process. This allows the system to adaptively adjust the cancellation strength across different frequency bands, optimizing crosstalk cancellation performance while accounting for the specific acoustic characteristics of compact speaker configurations
2Object-affected harmful factors
If traditional crosstalk cancellation methods are applied, then crosstalk is reduced, but spectral coloration increases and sound quality deteriorates
Solution Approach 1:
The patent applies frequency-dependent regularization parameters that vary across different frequency bands. This allows the system to apply stronger cancellation where crosstalk is most problematic while applying gentler cancellation where spectral coloration would be more noticeable, thereby optimizing the trade-off between crosstalk reduction and sound quality preservation
Solution Approach 2:
The patent applies different regularization strengths at different frequencies rather than using a uniform approach. This local quality adjustment ensures that crosstalk cancellation is applied more aggressively in frequency regions where it benefits stereo perception while being more conservative in regions where it would cause audible coloration
3Object-affected harmful factors
If band branching method is used for frequency dependent regularization, then crosstalk cancellation is optimized, but processor load and memory requirements increase
Solution Approach 1:
The patent merges the frequency-dependent regularization into a single unified transfer function inversion process rather than separately processing multiple frequency bands. This consolidation achieves frequency-selective cancellation performance while avoiding the computational overhead of band branching, thereby reducing processor load and memory requirements
Data Source
AI summary
An acoustic crosstalk canceller is determined for an asymmetric audio playback device, by determining a transfer function of an acoustic stereo playback path having asymmetries defined by speakers of the playback device. The transfer function is inverted to determine an inverse transfer function. The inverse transfer function is regularised by applying frequency dependent regularisation parameters to obtain an acoustic crosstalk canceller. Also, the inverse transfer function could be regularised for symmetric playback paths by applying aggregated frequency dependent regularisation parameters to obtain an acoustic crosstalk canceller without band branching.