Ear-Canal Microphone Signal Processing for Voice Extraction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing techniques for extracting a user's voice based on the difference in feature quantities between sound due to vibration conduction through air and sound due to vibration conduction through bone are not highly versatile.
Innovation Solution
A signal processing device and microphone device that utilize a first microphone inserted into the ear canal and a second microphone positioned outside the ear canal, with a determination unit to satisfy a first condition based on sound pressure levels, and a signal transmission unit to continue processing even after the condition is no longer satisfied, enhancing versatility in voice extraction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If voice extraction is based on difference in feature quantities between air conduction sound and bone conduction sound, then voice extraction can be performed, but the versatility is not high
Solution Approach 1:
The patent changes the parameters used for voice extraction from feature quantity differences to sound pressure level comparisons. By using sound pressure levels from microphones positioned at different locations (ear canal and outside ear canal) and comparing their ratios, the system achieves both high versatility and reliability in voice extraction without relying on bone conduction assumptions
Solution Approach 2:
The patent creates a universal voice extraction method that works for all users regardless of whether they are wearing hearing aids or not. The system uses a standardized approach based on sound pressure level ratios from microphone positions, making it applicable to diverse user conditions and environments, thereby achieving high versatility
2Productivity
If processing is stopped when the first condition is not satisfied, then processing efficiency is improved, but voice transmission is interrupted during varying environmental conditions
Solution Approach 1:
The patent maintains continuous voice transmission processing by introducing a second condition that allows processing to continue even when the first condition (sound pressure level ratio threshold) is not satisfied. The system transitions from a binary stop/start approach to a continuous monitoring approach where processing persists as long as either condition is met, ensuring uninterrupted voice transmission during environmental variations
Solution Approach 2:
The patent implements dynamic condition evaluation by using multiple conditions (first condition based on sound pressure level ratio, second condition based on alternative criteria) that can adapt to changing environmental conditions. The system dynamically switches between conditions to maintain processing continuity, making the voice transmission system more resilient to environmental changes
3Device complexity
If only the first condition is used for determining voice transmission, then the decision-making process is simple, but the system cannot adapt to varying environmental conditions
Solution Approach 1:
The patent segments the decision-making process into multiple independent conditions (first condition based on sound pressure level ratio, second condition based on alternative criteria). Each condition can be evaluated separately, and the system uses logical OR combination to determine whether to continue processing. This segmentation maintains relative simplicity while significantly improving adaptability to varying environmental conditions
Data Source
AI summary
A signal processing device determines whether a relationship between a first signal and a second signal satisfies a first condition, the first signal being based on an output of a first microphone inserted into an ear canal of a user, the second signal being based on an output of a second microphone positioned outside the ear canal. The signal processing device starts processing relating to transmission of a sound signal when it is determined that the first condition is satisfied, and that continues the processing, even after the first condition is not satisfied, during a period in which a second condition that differs from the first condition is satisfied.