Hearing Aid Signal De-correlation via Sinusoidal Modeling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Hearing devices, such as hearing aids, face challenges in achieving stability and improving speech audibility due to the linear nature of time-varying filters, which restricts the implementation of nonlinear processing like frequency shifting and phase randomization.

Innovation Solution

A hearing device comprising filters to separate input signals into low-frequency and high-frequency parts, with a synthesizing unit using sinusoidal modeling to generate a synthetic signal by shifting selected peaks to lower frequencies, and combining these with the high-frequency parts to create a de-correlated output, thereby enhancing stability and audibility.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a linear time-varying filter is used for signal processing, then dynamic-range compression and noise suppression can be effectively implemented, but nonlinear processing such as frequency shifting and phase randomization cannot be implemented

Engineering Contradiction:
Improvesignal processing capabilityVSAvoidprocessing system complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent divides the input signal into multiple frequency bands using filters, processes each band separately through sinusoidal modeling, and then combines the results. This segmentation allows nonlinear processing to be applied to specific frequency components without requiring the entire signal to be processed, thereby enabling frequency shifting and phase randomization while managing computational complexity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent applies different processing characteristics to different frequency bands. Each frequency band is processed through sinusoidal modeling with specific parameters (frequency, amplitude, phase) that are optimized for that band's characteristics. This local quality approach allows tailored nonlinear processing for each frequency region, improving overall adaptability while keeping individual processing operations manageable.

Inventive Principle:
Principle #3Local quality

2Adaptability or versatility

If sinusoidal modeling is applied to the entire signal bandwidth, then comprehensive signal processing is achieved, but computational burden increases significantly

Engineering Contradiction:
Improvesignal processing comprehensivenessVSAvoidcomputational efficiency
Core Design Contradiction:
Adaptability or versatilityVSProductivity

Solution Approach 1:

The patent segments the signal into multiple frequency bands using filters before applying sinusoidal modeling. By processing each band separately and combining the results, the system achieves comprehensive signal processing without the computational burden of processing the entire bandwidth simultaneously. The number of sinusoidal components is limited to what is necessary for each frequency band.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent applies sinusoidal modeling only to the extent necessary for effective processing of each frequency band, rather than applying it universally across the entire signal. This partial action approach processes only the essential frequency components needed for the specific processing goals, reducing unnecessary computational operations while maintaining processing comprehensiveness.

Inventive Principle:
Principle #16Partial or excessive action

3Reliability

If frequency shifting is applied to improve audibility for frequency-dependent hearing losses, then speech audibility is improved, but signal stability may be compromised

Engineering Contradiction:
Improvespeech audibilityVSAvoidsignal stability
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent applies frequency shifting through sinusoidal modeling selectively to specific frequency bands that correspond to the user's hearing loss characteristics. By tailoring the frequency transformation to match the individual's auditory profile, the system improves audibility in problematic frequency ranges while maintaining stability in other bands, achieving localized optimization rather than uniform processing.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent dynamically adjusts the frequency parameters of sinusoidal components based on the input signal characteristics and hearing loss profile. By changing frequency parameters adaptively rather than applying fixed transformations, the system can optimize audibility for frequency-dependent losses while maintaining signal stability through careful parameter selection and real-time adjustment.

Inventive Principle:
Principle #35Parameter changes

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

This approach significantly reduces computational burden while achieving high stability and improved audibility by de-correlating input and output signals, particularly beneficial for hearing aids with frequency-dependent hearing losses.

Implementation Method 1

a first synthesizing unit configured for generating a first synthetic signal from the first frequency part by using a first model based on a first periodic function

Methodology Applied
Scientific EffectSinusoidal modeling:

Implementation Method 2

shifting selected peaks to lower frequencies

Methodology Applied
Scientific EffectFrequency shifting:

Data Source

PatentEP2579252B1Stability and speech audibility improvements in hearing devices
Publication Date: 2020.04.22 GN HEARING AS
  • EP2579252B1 patent drawingFigure 1~2
  • EP2579252B1 patent drawingFigure 3~4
  • EP2579252B1 patent drawingFigure 5~6

AI summary

The present invention pertains to signal de-correlation for stability improvements in hearing devices such as hearing aids and to improve speech audibility in such. The hearing device comprises a first filter configured for providing a first frequency part of an input signal of the hearing device, the first frequency part comprising a low pass filtered part, a second filter configured for providing a second frequency part of the input signal, the second frequency part comprising a high pass filtered part, a first synthesizing unit configured for generating a first synthetic signal from the first frequency part using a first model based on a first periodic function, and a combiner configured for combining the second frequency part with the first synthetic signal for provision of a combined signal.