WO2008015215A2 - Arrangement avec un système de réduction de bruit actif - Google Patents

Arrangement avec un système de réduction de bruit actif Download PDF

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Publication number
WO2008015215A2
WO2008015215A2 PCT/EP2007/057904 EP2007057904W WO2008015215A2 WO 2008015215 A2 WO2008015215 A2 WO 2008015215A2 EP 2007057904 W EP2007057904 W EP 2007057904W WO 2008015215 A2 WO2008015215 A2 WO 2008015215A2
Authority
WO
WIPO (PCT)
Prior art keywords
unit
actuator
arrangement according
sensor
arrangement
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.)
Ceased
Application number
PCT/EP2007/057904
Other languages
German (de)
English (en)
Other versions
WO2008015215A3 (fr
Inventor
Harry Bachmann
Sigmund Eggenberger
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.)
ANOCSYS AG
Original Assignee
ANOCSYS AG
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 ANOCSYS AG filed Critical ANOCSYS AG
Publication of WO2008015215A2 publication Critical patent/WO2008015215A2/fr
Publication of WO2008015215A3 publication Critical patent/WO2008015215A3/fr
Anticipated expiration legal-status Critical
Ceased 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
    • G10K11/1785—Methods, e.g. algorithms; Devices
    • G10K11/17861—Methods, e.g. algorithms; Devices using additional means for damping sound, e.g. using sound absorbing panels
    • 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
    • G10K11/17854—Methods, e.g. algorithms; Devices of the filter the filter being an adaptive 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
    • G10K11/1785—Methods, e.g. algorithms; Devices
    • G10K11/17857—Geometric disposition, e.g. placement of microphones
    • 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
    • G10K11/17881—General system configurations using both a reference signal and an error signal the reference signal being an acoustic signal, e.g. recorded with a microphone
    • 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
    • G10K2210/12—Rooms, e.g. ANC inside a room, office, concert hall or automobile cabin

Definitions

  • the present invention relates to an arrangement with an active noise reduction system for reduction or
  • Noise sources are increasingly perceived as environmental pollution and are regarded as a reduction of
  • ANC Active Noise Canceling
  • the principle of Active Noise Canceling is based on the cancellation of sound waves due to interference. These interferences are generated by one or more electro-acoustic transducers, such as loudspeakers.
  • the signal radiated by the electro-acoustic transducers is calculated by means of a suitable algorithm and continuously corrected.
  • the basis for the calculation of the signal to be radiated by the electroacoustic transducers is the information supplied by one or more sensors. These are on the one hand information about the nature of the signal to be minimized.
  • a microphone can be used which detects the noise to be minimized.
  • information about the remaining residual signal is needed.
  • microphones can be used.
  • the basic principle used with active noise reduction was Paul Lueg in a patent document from the year 1935 and the disclosure number AT-141 998 B described. By this document is disclosed how noise in a tube can be extinguished by generating a signal with opposite phase.
  • An active noise reduction system requires information from at least one sensor (such as a microphone) that determines the residual error. Depending on the application and the algorithm used, additional sensors are provided that provide information about the nature of the signal to be minimized. Further, an active noise reduction system requires one or more actuators (for example in the form of loudspeakers) for outputting the
  • correction signal The information from the sensors must be converted from an analog-to-digital converter into a digital format. After being processed by the algorithm, the signal is retransmitted by a digital to analogue converter and transmitted to the actuators.
  • the effectiveness and efficiency of an ANC system in a room now depends, among other factors such as computing power and processing speed, also substantially on the acoustic properties of the actuators (such as speakers) and sensors
  • the distance between a sensor and an actuator is an important factor in an ANC application according to wavefield synthesis, and it is advantageous to place combinations, each consisting of one sensor and one actuator, close to each other, the effectiveness of this measure with respect to the achieved noise reduction, especially at low frequencies (preferably in the range below 300 Hz) shows.
  • a known application of this principle is, for example, an ANC headphone, based on a feedback arrangement that corresponds to a classic control loop, wherein the microphone signals are routed via a suitable controller to a loudspeaker. As a result, background noise in the music listener can be reduced by several dB.
  • an ANC system is based on a feedforward arrangement in which the signals from additional reference sensors (for example microphones) are fed to the loudspeakers via an adaptive algorithm.
  • additional reference sensors for example microphones
  • the object of the present invention is therefore to provide an arrangement of sensor and actuator units, which is suitable for active noise reduction and at the same time does not have the above disadvantages.
  • the invention relates to an arrangement with an active noise reduction system for the reduction or elimination of disturbing noises in a room with at least one window.
  • the inventive arrangement comprises:
  • the invention is characterized in that at least one outer sensor unit and at least one communiqués are arranged outside the room, wherein both the at least one outer sensor unit and the at least one communiquéuatorü are operatively connected to the processing unit.
  • the arrangement according to the invention has the particular advantage that the sound entering the room is already reduced in the area in front of the window.
  • the outer sensor and outer actuator units are positioned in the region in front of a window, for example in the region of a roller shutter or a sun blind.
  • a variant of the inventive arrangement is that both the at least one
  • Outside sensor unit and the at least one Selfaktuatorü are arranged in the region of the at least one window.
  • a further embodiment variant of the arrangement according to the invention is that the number of external sensor units is equal to the number of external actuator units.
  • a still further embodiment variant of the arrangement according to the invention consists in that in each case an external sensor unit and an external actuator unit form a combined actuator / sensor unit.
  • Another variant of the inventive arrangement is that an even number of combined actuator / sensor units is present.
  • Another variant of the inventive arrangement is that the combined Actuator / sensor units are arranged around the window, wherein in each case two combined actuator / sensor units are arranged opposite to each other.
  • a further embodiment variant of the arrangement according to the invention consists in that at least two combined actuator / sensor units are arranged horizontally opposite and / or at least two combined actuator / sensor units vertically opposite one another.
  • a further embodiment variant of the arrangement according to the invention consists in that the actuator units are loudspeakers.
  • the sensor units are microphones.
  • a further embodiment variant of the arrangement according to the invention consists in that the active noise reduction can be carried out on the "feedforward" principle.
  • a further embodiment variant of the arrangement according to the invention consists in the fact that an algorithm of the type "feedforward" or of the type “feedback” can be used in the processing unit.
  • a further embodiment variant of the arrangement according to the invention is that to achieve a further Noise reduction passive measures, in particular a use of sound-insulating windows, can be used.
  • Fig. 1 shows a room with an active
  • Fig. 2 is a highly simplified block diagram of a
  • FIG. 3 is a simplified equivalent circuit diagram of an active noise reduction system using a known "feedforward" method.
  • FIG. 4 shows a cross section through the wall of a room equipped with a window with an inventive arrangement of the actuator or sensor units, again in a schematic representation
  • Fig. 5 shows a further cross section through the with a
  • FIG. 6 is an elevation of a wall of a room equipped with a window with a erfmdungsgemassen arrangement of actuator or sensor units, again in a schematic
  • FIG. 7 is another elevation of a wall of a room equipped with a window with a erfmdungsgemassen arrangement of actuator or
  • FIG. 8 is a highly simplified block diagram of an active noise reduction system using a known algorithm.
  • FIG. 1 shows a room 1 with a window 9 in plan view with an active noise reduction system, which consists of a processing unit 20, a sensor unit 21, an actuator unit 24 and an outdoor sensor unit 22.
  • the processing unit 20 is operatively connected via connections 19 to the sensor unit 21, the actuator unit 24 and the external sensor unit 22.
  • the sensor unit 21 is placed inside the room 1 to be quieted for detecting residual noise
  • the outside sensor unit 22 for detecting noises is arranged in an outside area 2 outside the room 1.
  • the actuator 24 a correction signal is output to the room 1, with which the in Room 1 occurring unwanted noise eliminated or at least attenuated.
  • the sensor units 21 and the outdoor sensor unit 22 are preferably designed as microphones and the actuator units 24 preferably as loudspeakers.
  • Fig. 2 shows a block diagram of a
  • Noise reduction system in the arrangement of a known feedback method.
  • the output signal of a microphone 21 is applied to a processing unit 20, which generates a correction signal and transmits it to a loudspeaker unit 24.
  • Fig. 3 shows an equivalent circuit diagram of an embodiment variant in a schematic representation. It is a so-called adaptive
  • Noise reduction system with the help of which a noise in a room 1 (Fig. 1 or 2) using the principle of signal cancellation is eliminated or at least reduced.
  • the space 1 to be monitored has a transfer function H, which is supplied with an input signal x. This is an input signal x recorded with the aid of a microphone unit (not shown in FIG. 3), which is further supplied to a filter unit 3 and an adaptive calculation unit 4.
  • An actual output signal d which is formed by the transfer function H and the input signal x, is compensated in space 1 by an estimated output signal y by applying this to a loudspeaker (not shown in FIG Room 1 is supplied.
  • the transfer function H of the room 1 is estimated in the filter unit 3 with the aid of a in the adaptive calculation unit 4.
  • the result of the estimation is an estimated transfer function H, from which the estimated output signal y is generated together with the input signal x.
  • the superposition of the two output signals y and y is shown in the equivalent circuit diagram of FIG. 3 with an addition unit 5, wherein the sign of the estimated output signal y is reversed before addition, so that as a result of the addition of the difference (hereinafter referred to as error signal e) both output signal y and y is present.
  • This error signal e is fed together with the input signal x to the adaptive calculation unit 4, in which the coefficients of the estimated transfer function H are set in such a way that the error signal is as small as possible using an adaptive algorithm, for example an Fx algorithm.
  • a suitable one is fed together with the input signal x to the adaptive calculation unit 4, in which the coefficients of the estimated transfer function H are set in such a way that the error signal is as small as possible using an adaptive
  • the transfer function H describes the acoustic behavior of the room 1. In addition to the acoustic behavior in the transfer function H also
  • FIG. 4 shows a cross section through a wall of a room 1 equipped with a window 9 with an arrangement according to the invention of the actuator or sensor units.
  • Sound waves 14 of the sound source 15 located in the outer area 2 propagate wave-shaped, are detected by an outdoor sensor unit 22 (for example a microphone) and impinge on the masonry 10, 10 x and on the outer window pane 11.
  • an outdoor sensor unit 22 for example a microphone
  • further external sensor units 16 for example microphones
  • Aussenaktuatorüen 17 placed in the area of the window frame 13, 13 ⁇ or surrounding walls 10 on the building exterior, and serve to sound reduction of light emitted from the source 15 the sound field in the region between the window 11 and the source 15.
  • a window with Double glazing is the outer window 11 separated by the gap 12 of the inner window 11 11 ⁇ , and the two windows 11 and 11 x are fixed in the window frame 13, which in turn is anchored in the masonry 10, 10 ⁇ .
  • the residual sound passing through the open or closed window 9 into the room 1 is detected on the one hand by the sensor unit 21 in the room 1 (for example a microphone), and the correction signal (estimated output signal y) is transmitted by the actuator unit 24 (for example a loudspeaker), thus a further reduction of noise in room 1 takes place.
  • the Sensor units 16, 21, 22 and the actuator units 17, 24 are operatively connected to the processing unit 20.
  • FIG. 5 again shows a cross section through a wall 23 of a room 1 provided with a window 9 with an arrangement of the actuator or sensor units according to the invention, wherein, in contrast to FIG. 4, the outer sensor unit 16 and the outer actuator unit 17 advantageously turn into one an actuator and a sensor unit existing, combined unit 18 are summarized.
  • the window 9 is shown in the half-open state.
  • Fig. 6 shows the wall 23 of a room 1 in elevation, with a window 9 is located between the ceiling 22 and the bottom 21. Outside the window, the placement of the combined actuator / sensor units 18 takes place in a horizontal arrangement. In addition, in the vertical direction, the combined actuator / sensor units 19 are arranged so that by selecting the distances xl, yl advantageously optimal sound reduction in the horizontal and vertical directions is achieved. It is expressly pointed out that instead of the combined actuator / sensor units 18, 19, it is also possible to use individual actuator units 17 and individual sensor units 16, without the principle according to the invention being abandoned.
  • the distances xl, yl of the combined actuator / sensor units 18, 19 is possible on the Wavelength ⁇ of the interference signal to be eliminated tuned. If the distances x1, y1 are the same size as half the wavelength (ie ⁇ / 2), a maximum extinction of the interference signal is obtained. In the event of a deviation from this optimum setting for a noise signal with a certain frequency or if a noise with a certain spectral distribution is to be eliminated or at least reduced, the noise reduction takes place in a correspondingly reduced manner.
  • road or aircraft noise has an approximate center frequency of 500 Hz. This results in an average propagation velocity of a sound wave in air of 300 m / s a value for ⁇ / 2 of about 30 cm. Accordingly, the combined
  • Actuator / sensor units 18 and 19 to be arranged at a distance of 30 cm.
  • 7 again shows the wall 23 of a room 1 with a window 9. In contrast to FIG. 6, in this example the window 9 has smaller dimensions, which reduces the number of combined actuator / sensor units.
  • the arrangement is again in a horizontal and vertical manner, wherein by selecting the distances x2, y2 advantageously optimal sound reduction in the horizontal and vertical directions is achieved.
  • the same rules for determining the distances x2 and y2 are also used in this embodiment, as was already the case with the embodiment according to FIG. 6 for the distances x1 and y2.
  • the actuator unit is located locally close to the sensor unit (eg, a reference microphone), it is recommended to use an algorithm that has a feedback.
  • the output signal y estimated by the filter 3 is applied in addition to the feedback unit 8 and is paid together in the addition unit 5 with the actual output signal d.
  • the output signal y x the
  • Feedback unit 8 is paid after previous inversion in a further addition unit 29 with the input signal x together, wherein the sum signal x ⁇ of both the adaptive calculation unit 4 and the filter 3 is applied.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Soundproofing, Sound Blocking, And Sound Damping (AREA)
  • Exhaust Silencers (AREA)

Abstract

L'invention concerne un arrangement avec un système de réduction de bruit actif destiné à réduire ou à éliminer les bruits parasites dans une pièce (1) comprenant au moins une fenêtre (9). L'arrangement comprend une unité (20) de traitement, au moins une unité (21, 22) de détection dans la pièce (1) et au moins une unité (24) d'actionnement dans la pièce (1). Selon l'invention, l'au moins une unité (21, 22) de détection et l'au moins une unité (24) d'actionnement sont en liaison active avec l'unité (20) de traitement. L'invention se caractérise en ce qu'au moins une unité (16) de détection externe et au moins une unité (17) d'actionnement externe sont disposées à l'extérieur de la pièce (1). Selon l'invention, l'au moins une unité (16) de détection externe ainsi que l'au moins une unité (17) d'actionnement externe sont en liaison active avec l'unité (20) de traitement.
PCT/EP2007/057904 2006-07-31 2007-07-31 Arrangement avec un système de réduction de bruit actif Ceased WO2008015215A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH1235/06 2006-07-31
CH12352006 2006-07-31

Publications (2)

Publication Number Publication Date
WO2008015215A2 true WO2008015215A2 (fr) 2008-02-07
WO2008015215A3 WO2008015215A3 (fr) 2008-05-22

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2007/057904 Ceased WO2008015215A2 (fr) 2006-07-31 2007-07-31 Arrangement avec un système de réduction de bruit actif

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101185862B1 (ko) 2011-01-05 2012-09-25 한국과학기술원 소음 제어 장치 및 방법
CN104405272A (zh) * 2014-10-21 2015-03-11 西安理工大学 一种降噪纱窗及降噪方法
CN108074559A (zh) * 2017-12-04 2018-05-25 成都星达微科技有限公司 一种基于窗户开闭及红外感应的校园宿舍主动降噪系统
US11195506B2 (en) * 2018-12-03 2021-12-07 Toyota Motor Engineering & Manufacturing North America, Inc. Sound-modulating windows
US20240221716A1 (en) * 2018-09-14 2024-07-04 Gn Hearing A/S Method for noise cancellation in a room and sound system

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3613801B2 (ja) * 1992-09-29 2005-01-26 マツダ株式会社 車両の振動低減装置
GB9920883D0 (en) * 1999-09-03 1999-11-10 Titon Hardware Ventilation assemblies
DE10052093B4 (de) * 2000-10-20 2004-06-24 Jakob, André, Dr. Verwendung von Schallerzeugern in Fensterrahmen zur Schalldämmung

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101185862B1 (ko) 2011-01-05 2012-09-25 한국과학기술원 소음 제어 장치 및 방법
CN104405272A (zh) * 2014-10-21 2015-03-11 西安理工大学 一种降噪纱窗及降噪方法
CN104405272B (zh) * 2014-10-21 2016-01-27 西安理工大学 一种降噪纱窗及降噪方法
CN108074559A (zh) * 2017-12-04 2018-05-25 成都星达微科技有限公司 一种基于窗户开闭及红外感应的校园宿舍主动降噪系统
US20240221716A1 (en) * 2018-09-14 2024-07-04 Gn Hearing A/S Method for noise cancellation in a room and sound system
US12562145B2 (en) * 2018-09-14 2026-02-24 Gn Hearing A/S Method for noise cancellation in a room and sound system
US11195506B2 (en) * 2018-12-03 2021-12-07 Toyota Motor Engineering & Manufacturing North America, Inc. Sound-modulating windows

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