Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Active noise control system and method based on improved FxLMS algorithm

A technology of active noise control and algorithm, applied in the research field of secondary channel modeling method, can solve the problems of secondary channel modeling divergence, noise reduction performance degradation, system easy to diverge, etc.

Pending Publication Date: 2018-10-16
CHONGQING UNIV OF POSTS & TELECOMM
View PDF2 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The fixed step size is easy to cause the divergence of the secondary channel modeling in the ANC system when the environment changes suddenly, thus affecting the noise reduction performance of the ANC system; in addition, the training signal (auxiliary random white noise) of the secondary channel uses fixed power consumption , it will also make the system easy to diverge, resulting in a decrease in noise reduction performance

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Active noise control system and method based on improved FxLMS algorithm
  • Active noise control system and method based on improved FxLMS algorithm
  • Active noise control system and method based on improved FxLMS algorithm

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0060] The technical solutions in the embodiments of the present invention will be described clearly and in detail below with reference to the drawings in the embodiments of the present invention. The described embodiments are only some of the embodiments of the invention.

[0061] The technical scheme that the present invention solves the problems of the technologies described above is:

[0062] The ANC system proposed by the present invention adopts Matlab8.6 for simulation.

[0063] as attached figure 1 The reference noise signal x(n) shown is input from the reference microphone, and after being processed by the ANC control system, a control signal y(n) is generated, and y(n) drives the speaker to send out a secondary signal. If the frequency of the anechoic signal emitted by the loudspeaker is the same as that of the reference noise signal and the amplitude is opposite, they will cancel each other out, thereby achieving the effect of noise reduction. The error microphon...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses an active noise control system and method based on an improved FxLMS algorithm. The active noise control system mainly comprises five modules as follows: (1) the FxLMS algorithm, (2) a secondary channel, (3) a performance monitor, (4) a variable-power white noise generator, and (5) a main channel path. The invention aims at improving noise reduction performance of an ANC system as well as modeling precision and convergence rate of the secondary channel; in accordance with innovation points, a training signal (auxiliary random white noise) of the secondary channel undergoes power scheduling, and then performance in (2) is observed, wherein injection of the auxiliary random white noise in the (4) is stopped when a following relation is satisfied: [mu]Smax-[mu]S<[alpha](1*10<-5><[alpha]<1*10<-3>), and injection of the auxiliary random white noise in the (4) is started once again when a following relation is satisfied: 20log10|f(n)|<0. Therefore, mutual transformation of the secondary channel between online modeling and offline modeling is achieved, and the finally obtained ANC system is relatively high in modeling precision and noise reduction performance. Theactive noise control system has the characteristics of simple structure, easy adaption to environmental change and big-variance auxiliary white noise and the like.

Description

technical field [0001] The invention belongs to the technical field of noise elimination, and in particular relates to a research on a secondary channel modeling method in an active noise control system (ANC) for low-frequency noise elimination based on an FxLMS algorithm. Background technique [0002] In recent years, with the continuous growth of industrial equipment such as fans, engines, compressors and transformers, acoustic noise has gradually become a serious problem. The traditional noise reduction method is passive noise control: using acoustic packaging, installing mufflers, and designing sound insulation structures to reduce noise. The noise reduction effect achieved in the range is insignificant and bulky and costly. The active noise control (ANC) has a good noise reduction effect on low-frequency noise [1] , and thus received great attention. [0003] As an important part of noise cancellation, ANC's main design challenge is related to the secondary channel. ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): G10K11/178
CPCG10K11/17813G10K2210/3035G10K2210/3028G10K2210/3012
Inventor 袁军刘东旭唐晓斌王巍王冠宇吕韦喜
Owner CHONGQING UNIV OF POSTS & TELECOMM
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com