Wearable Audio Filters for Balanced Noise Cancellation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing noise cancellation technologies in wearable devices fail to achieve balanced attenuation across all noise cancellation modes, particularly in in-between modes, leading to unbalanced frequency attenuation and an unnatural sound experience.
Innovation Solution
A wearable audio device with sensors, inputs, and processors that dynamically adjust filter coefficients based on user input to achieve balanced active and passive noise cancellation, using a coefficient table to correlate user-selectable attenuation levels with filter settings, ensuring flat or near-flat attenuation across frequency ranges.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If in-between noise cancellation modes are implemented with various levels of active noise cancellation, then user comfort and versatility are improved, but the attenuation becomes unbalanced across frequencies (high frequencies cannot be attenuated at the same levels as low frequencies)
Solution Approach 1:
The patent applies local quality by implementing frequency-dependent filter coefficients that allow different attenuation characteristics for different frequency ranges. The system uses separate filter coefficients for low frequencies and high frequencies, enabling optimized attenuation balance across the frequency spectrum while maintaining multiple noise cancellation modes.
Solution Approach 2:
The patent implements parameter changes by dynamically adjusting filter coefficients based on the selected noise cancellation mode. The system stores multiple sets of filter coefficients corresponding to different attenuation levels and selectively applies them to achieve balanced attenuation across frequencies while providing versatile noise cancellation modes.
2Manufacturing precision
If multiple filter coefficients are stored for different attenuation levels, then attenuation precision is improved, but device complexity increases
Solution Approach 1:
The patent applies preliminary action by pre-calculating and storing optimal filter coefficients for different attenuation levels before the device is used. The coefficient table is prepared in advance with frequency-dependent values that correspond to various noise cancellation modes, eliminating the need for real-time calculations and reducing processing complexity during operation.
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 provides a seamless and natural sound experience by achieving balanced noise attenuation across frequencies, allowing users to selectively adjust noise levels for a more preferred audio output.
Implementation Method 1
at least one sensor arranged to: sense at least one characteristic of the initial audio output signal, sense noise external to the wearable audio device, and provide at least one sensor signal related to at least one characteristic of the sensed initial audio output signal and at least one characteristic of the sensed noise
Implementation Method 2
the speaker can be configured to produce sound having a similar amplitude and a similar-to-opposite phase to the unwanted sound. The sound produced is then combined with the unwanted sound and, due to the superposition of the sound waves, can reduce the amplitude of the opposing phase noise
Data Source
AI summary
A wearable audio device can include at least one speaker to provide an initial audio output signal; at least one sensor arranged to: sense at least one characteristic of the initial audio output signal, sense noise external to the wearable audio device, and provide at least one sensor signal related to at least one characteristic of the sensed initial audio output signal and at least one characteristic of the sensed noise; at least one input arranged to accept an input related to a desired level of attenuation of the noise; a processor arranged to: receive the at least one sensor signal and the selected desired level of attenuation, select at least one coefficient from a coefficient table based on the at least one sensor signal or the selected desired level of attenuation, and provide an attenuation signal related to the selected at least one coefficient; and at least one filter arranged to receive the attenuation signal from the processor and produce a filtered audio signal based on the attenuation signal, wherein the at least one speaker is configured to provide an attenuated audio output based on the filtered audio signal.