GB2191363A - Transfer function generation for active noise cancellation - Google Patents

Transfer function generation for active noise cancellation

Info

Publication number
GB2191363A
GB2191363A GB08712273A GB8712273A GB2191363A GB 2191363 A GB2191363 A GB 2191363A GB 08712273 A GB08712273 A GB 08712273A GB 8712273 A GB8712273 A GB 8712273A GB 2191363 A GB2191363 A GB 2191363A
Authority
GB
United Kingdom
Prior art keywords
omega
field
transfer function
cancelling
noise cancellation
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB08712273A
Other versions
GB2191363B (en
GB8712273D0 (en
Inventor
Brian Alan Taylor
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
CONTRANOISE Ltd
Original Assignee
CONTRANOISE Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by CONTRANOISE Ltd filed Critical CONTRANOISE Ltd
Publication of GB8712273D0 publication Critical patent/GB8712273D0/en
Publication of GB2191363A publication Critical patent/GB2191363A/en
Application granted granted Critical
Publication of GB2191363B publication Critical patent/GB2191363B/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1781—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase characterised by the analysis of input or output signals, e.g. frequency range, modes, transfer functions
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1785—Methods, e.g. algorithms; Devices
    • G10K11/17853—Methods, e.g. algorithms; Devices of the filter
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1787—General system configurations
    • G10K11/17875—General system configurations using an error signal without a reference signal, e.g. pure feedback
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1787—General system configurations
    • G10K11/17879—General system configurations using both a reference signal and an error signal
    • G10K11/17883—General system configurations using both a reference signal and an error signal the reference signal being derived from a machine operating condition, e.g. engine RPM or vehicle speed
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/10—Applications
    • G10K2210/121—Rotating machines, e.g. engines, turbines, motors; Periodic or quasi-periodic signals in general
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/10—Applications
    • G10K2210/128—Vehicles
    • G10K2210/1282—Automobiles
    • G10K2210/12822—Exhaust pipes or mufflers
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/10—Applications
    • G10K2210/129—Vibration, e.g. instead of, or in addition to, acoustic noise
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3011—Single acoustic input
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3012—Algorithms
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3023—Estimation of noise, e.g. on error signals
    • G10K2210/30232—Transfer functions, e.g. impulse response
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3025—Determination of spectrum characteristics, e.g. FFT
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/301—Computational
    • G10K2210/3045—Multiple acoustic inputs, single acoustic output

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)
  • Fittings On The Vehicle Exterior For Carrying Loads, And Devices For Holding Or Mounting Articles (AREA)
  • Exhaust Silencers (AREA)

Abstract

A method for the active cancellation of an incident vibration field (N(i omega )) which comprises superposing on the incident field, a cancelling vibration field (C(i omega )) to create a residual vibration field (R(i omega )) and operating on the residual field with a transfer function to obtain an updated cancelling field, the transfer function being divided by a reference point (10) into an upstream part (Fi(i omega )) and a downstream part (Fo(i omega )) and the downstream part (Fo(i omega )) of the transfer function being periodically updated by multiplying the last obtained value (Fon(i omega )) by a factor which is the ratio of a computational value of the last cancelling field (Cn(i omega )) and a computational value for the sum of previous residual fields (R(i omega )).
GB08712273A 1985-10-18 1986-10-17 Transfer function generation for active noise cancellation Expired GB2191363B (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB858525800A GB8525800D0 (en) 1985-10-18 1985-10-18 Transfer function generation
PCT/GB1986/000635 WO1987002496A1 (en) 1985-10-18 1986-10-17 Transfer function generation for active noise cancellation

Publications (3)

Publication Number Publication Date
GB8712273D0 GB8712273D0 (en) 1987-07-01
GB2191363A true GB2191363A (en) 1987-12-09
GB2191363B GB2191363B (en) 1988-11-16

Family

ID=10586918

Family Applications (2)

Application Number Title Priority Date Filing Date
GB858525800A Pending GB8525800D0 (en) 1985-10-18 1985-10-18 Transfer function generation
GB08712273A Expired GB2191363B (en) 1985-10-18 1986-10-17 Transfer function generation for active noise cancellation

Family Applications Before (1)

Application Number Title Priority Date Filing Date
GB858525800A Pending GB8525800D0 (en) 1985-10-18 1985-10-18 Transfer function generation

Country Status (4)

Country Link
EP (1) EP0243433A1 (en)
AU (1) AU6523186A (en)
GB (2) GB8525800D0 (en)
WO (1) WO1987002496A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5263019A (en) * 1991-01-04 1993-11-16 Picturetel Corporation Method and apparatus for estimating the level of acoustic feedback between a loudspeaker and microphone

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8717043D0 (en) * 1987-07-20 1987-08-26 Plessey Co Plc Noise reduction systems
GB2230920B (en) * 1989-04-25 1993-12-22 Topexpress Ltd Active sound and/or vibration control
JP3016972B2 (en) * 1992-09-03 2000-03-06 パロマ工業株式会社 Pulse combustor
FR2774606B1 (en) 1998-02-11 2000-03-17 Rhodia Chimie Sa PROCESS FOR REMOVING HALOGENATED COMPOUNDS FROM GASES OR LIQUIDS

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2069280A (en) * 1981-01-05 1981-08-19 Ross C F Process of testing for a sound control system
GB2122052A (en) * 1982-06-09 1984-01-04 Plessey Co Plc Reducing noise or vibration
GB2154830A (en) * 1984-02-21 1985-09-11 Nat Res Dev Attenuation of sound waves

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2069280A (en) * 1981-01-05 1981-08-19 Ross C F Process of testing for a sound control system
GB2122052A (en) * 1982-06-09 1984-01-04 Plessey Co Plc Reducing noise or vibration
GB2154830A (en) * 1984-02-21 1985-09-11 Nat Res Dev Attenuation of sound waves

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
IEEE INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS PROCEEDINGS, 1978, NEW YORK (US)PAGES 232-236 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5263019A (en) * 1991-01-04 1993-11-16 Picturetel Corporation Method and apparatus for estimating the level of acoustic feedback between a loudspeaker and microphone

Also Published As

Publication number Publication date
AU6523186A (en) 1987-05-05
GB8525800D0 (en) 1985-11-20
GB2191363B (en) 1988-11-16
EP0243433A1 (en) 1987-11-04
WO1987002496A1 (en) 1987-04-23
GB8712273D0 (en) 1987-07-01

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Legal Events

Date Code Title Description
732 Registration of transactions, instruments or events in the register (sect. 32/1977)
732 Registration of transactions, instruments or events in the register (sect. 32/1977)
732E Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977)
PE20 Patent expired after termination of 20 years

Effective date: 20061016