Hybrid Active Noise Control Zone Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional active noise cancellation (ANC) systems are ineffective in large listening environments due to increased modal density, which requires complex hardware setups and is cost- and weight-prohibitive for applications like aircraft and automobiles.
Innovation Solution
A hybrid ANC system is implemented by dividing the listening environment into multiple zones, each with its own ANC system, combining centralized and decentralized ANC approaches to reduce hardware requirements and processing complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a centralized ANC system is used in large listening environments, then noise cancellation can be implemented with simpler hardware, but the system becomes ineffective due to increased modal density
Solution Approach 1:
The patent divides the large listening environment into multiple zones, with each zone having its own control unit that independently processes acoustic data and generates noise cancellation signals. This segmentation allows each control unit to handle a manageable subset of acoustic modes, maintaining effectiveness while avoiding the hardware complexity of a fully decentralized system. The zones are separated by boundaries that may include open space, and each zone has dedicated speakers and microphones assigned to it.
2Reliability
If a decentralized ANC system is used in large listening environments, then noise cancellation effectiveness is improved, but hardware requirements and cost increase significantly
Solution Approach 1:
The patent implements a hybrid architecture where the listening environment is divided into zones, but multiple zones can share a common control unit. This reduces the number of control units needed compared to a fully decentralized system, thereby reducing hardware requirements and cost while still maintaining the effectiveness benefits of decentralized control within each zone.
Solution Approach 2:
The patent allows control units to serve multiple zones, making the control units universal rather than dedicated to single zones. This multi-functionality reduces the total number of control units required, thereby reducing hardware complexity and cost while maintaining noise cancellation effectiveness through zone-specific processing.
3Reliability
If the number of speakers is increased to match the number of acoustic modes, then noise cancellation effectiveness improves, but system cost and weight become prohibitive
Solution Approach 1:
By dividing the environment into zones and having each control unit manage only the acoustic modes relevant to its zone, the system achieves effective noise cancellation with fewer total speakers than would be required in a fully decentralized system. Each speaker is assigned to specific zones where it is most effective, reducing the overall speaker count and system weight while maintaining effectiveness.
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 hybrid ANC system effectively cancels noise in large environments with lower hardware needs, making it more cost-effective and suitable for weight-sensitive applications.
Implementation Method 1
Inverses of one or more waveforms associated with the noise are then generated and reproduced via one or more speakers in order to destructively interfere with or 'cancel out' the noise
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A technique for reducing noise in a listening environment. The technique includes dividing the listening environment into a plurality of zones, where each zone is associated with a different active noise cancellation (ANC) system. A boundary between a first zone included in the plurality of zones and a second zone included in the plurality of zones comprises open space. The technique further includes assigning a plurality of acoustic sensors and a plurality of speakers to the ANC system associated with each zone included in the plurality of zones. The technique further includes, for each zone included in the plurality of zones, acquiring acoustic data via the plurality of acoustic sensors, processing the acoustic data, via a processor, to generate noise cancellation signals, and outputting the noise cancellation signals via the plurality of speakers.