Hearing Device Spatial Sound Positioning via Binaural Filters
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hearing impaired individuals face challenges in understanding speech in noisy environments due to internalized sound fields produced by conventional hearing aids, which hinder their ability to separate and focus on specific sound sources.
Innovation Solution
A new hearing device system that utilizes binaural filters with directional transfer functions to simulate Head-Related Transfer Functions, allowing users to perceive sound sources as originating from specific spatial directions, enhancing sound source separation and localization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional hearing aids amplify sound to restore audibility, then hearing threshold is improved, but ability to understand speech in noise deteriorates
Solution Approach 1:
The patent segments the audio signal into multiple frequency channels and applies different processing to each channel. By dividing the signal processing into distinct pathways, the system can selectively enhance speech frequencies while suppressing noise frequencies in each channel, thereby improving speech intelligibility in noisy environments while maintaining overall audibility.
Solution Approach 2:
The patent applies local quality enhancement by selectively processing specific frequency ranges associated with speech sounds differently from other frequency ranges. Speech-critical frequency channels receive enhanced processing including noise reduction and gain adjustment, while non-speech channels are processed differently, creating localized quality improvement where it matters most for speech understanding.
2Loss of information
If binaural filters with directional transfer functions are used to externalize sound fields, then sound source separation is improved, but device complexity increases
Solution Approach 1:
The patent uses copying by implementing digital simulations of Head-Related Transfer Functions (HRTFs) through software-based binaural filters. Instead of requiring complex physical acoustic structures, the system creates virtual copies of natural spatial hearing cues through digital signal processing, achieving sound source externalization and separation using computationally efficient filter algorithms.
Solution Approach 2:
The patent replaces mechanical/acoustic spatial separation mechanisms with electronic/digital signal processing. By substituting physical acoustic structures with digital binaural filtering and HRTF-based processing, the system achieves sound source separation and externalization through software algorithms rather than complex mechanical or acoustic hardware designs.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Improves the user's ability to distinguish and focus on desired sound sources by externalizing sound fields, reducing listening fatigue and enhancing speech intelligibility in noisy environments.
Implementation Method 1
The binaural filter is configured to output a right ear signal and a left ear signal that are equal to the input signal multiplied with a right gain and a left gain, respectively, and/or that are phase shifted with a resulting phase shift with relation to each other, wherein the right gain, the left gain and/or the phase shift correspond to a Head-Related Transfer Function
Implementation Method 2
a first transducer for transmission of a first hearing device output signal towards a first ear of the user, and a second transducer for transmission of a second hearing device output signal towards a second ear of the user
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A new hearing device system is disclosed herein. The hearing device system has a hearing device and a control device that allows a user to select perceived directions of arrival of selected sound signals transmitted to the hearing device.