Active Noise Cancellation Adaptation for Personal Listening Device Vibrations
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Personal listening devices with active noise control (ANC) systems face instability and generate audible artifacts when used during vibrations, such as walking or riding, due to incorrect sound field capture by microphones, leading to uncomfortable or nauseous experiences for users.
Innovation Solution
Incorporating an accelerometer and/or pressure sensor to detect vibrations in personal listening devices, which allows the ANC system to reconfigure and generate a second anti-noise signal based on detected vibrations, thereby reducing ambient noise and minimizing artifacts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the ANC system uses reference microphone and error microphone to generate anti-noise signal, then ambient noise can be cancelled, but during vibrations the sound field capture becomes incorrect causing audible artifacts and user discomfort
Solution Approach 1:
The patent introduces accelerometers and pressure sensors as intermediary devices that detect vibrations and provide feedback to the ANC system. These sensors act as mediators between the physical vibration state and the digital signal processing, enabling the system to distinguish between ambient noise and vibration-induced artifacts, thereby preventing incorrect anti-noise generation during movement
Solution Approach 2:
The patent implements dynamic reconfiguration of the ANC system based on real-time vibration detection. When vibrations are detected through accelerometers or pressure sensors, the system dynamically switches between different ANC modes or adjusts filter parameters, allowing the anti-noise generation process to adapt to changing physical conditions and maintain accuracy during movement
2Adaptability or versatility
If the ANC system operates during vibrations such as walking or running, then the device can be used in motion, but the adaptive filters converge to wrong solutions generating significant artifacts
Solution Approach 1:
The patent implements feedback mechanisms where accelerometers and pressure sensors continuously monitor the physical state of the device during movement. This feedback information is fed back to the signal processing unit, which uses it to adjust the ANC algorithm parameters or switch between different processing modes, ensuring reliable and stable noise cancellation performance across various motion conditions
Solution Approach 2:
The patent changes key parameters of the ANC system based on detected vibration levels and patterns. When vibrations are detected, the system modifies filter coefficients, adaptation rates, or threshold values to prevent convergence to incorrect solutions, thereby maintaining ANC reliability during dynamic usage scenarios such as walking, running, or vehicle transport
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
The solution effectively stabilizes ANC performance by adapting the anti-noise signal generation in response to device vibrations, enhancing user comfort by reducing unwanted noise and artifacts during movement.
Implementation Method 1
The inertial sensor may detect motion of the PLD and generate a motion signal
Implementation Method 2
The pressure sensor may detect compression of a portion of the PLD and generate pressure sensor signal
Implementation Method 3
The speaker may receive an anti-noise signal and a desired audio signal from an electronic device
Implementation Method 4
The ANC technique cancels the external or ambient sound by generating a control signal that causes the personal listening device to introduce an anti-noise, which is an additional, electronically controlled sound field designed to counteract or destructively interfere with the desired external or ambient sound
Data Source
AI summary
Personal listening device (PLD) includes earphone housing having therein (a) inertial sensor to detect motion of PLD and to generate motion signal, (b) pressure sensor to detect compression of portion of PLD and to generate pressure sensor signal, and (c) speaker to receive anti-noise signal and desired audio signal from electronic device, and active noise control (ANC) system to generate anti-noise signal as being one of first or second anti-noise signal. ANC system includes processor, vibration detector to detect vibration of the PLD based on at least one of motion signal or pressure sensor signal, and ANC anti-noise generator to generate first anti-noise signal when vibrations are not detected by vibration detector, and to generate second anti-noise signal when vibrations are detected by vibration detector. Second anti-noise signal is based on detected vibrations. Processor reconfigures ANC system for ANC anti-noise generator to generate second anti-noise signal. Other embodiments are described.