公开(公告)号：EP0967592B1

公开(公告)日：2007-01-24

申请号：EP99203047.8

申请日：1994-06-23

申请人： NOISE CANCELLATION TECHNOLOGIES, INC.

发明人： Jones, Owen

IPC分类号： G10K11/178

CPC分类号： G10K11/17857 ,  A61F2011/145 ,  G10K11/17855 ,  G10K11/17881 ,  G10K11/17885 ,  G10K2210/108 ,  G10K2210/1081 ,  G10K2210/3011 ,  G10K2210/3013 ,  G10K2210/3019 ,  G10K2210/3028 ,  G10K2210/3056 ,  G10K2210/3214 ,  G10K2210/503

摘要： An active noise cancellation system includes a series of features for more effective cancellation, greater reliability, and improved stability. A particular feature adapted for headset systems includes locating a residual microphone radially offset from the centre of a sound generator to detect a signal more similar to that incident upon the eardrum of the user. In addition, an open back headset design includes perforations on the side of the headset instead of the back, so that the perforations are less susceptible to inadvertent blockage. The system also includes a mechanism for detecting changes in the acoustic characteristics of the environment that may be caused, for example, by pressure exerted upon the earpieces, and that may destabilize the cancellation system. The system automatically responds to such changes, for example, by reducing the gain or the frequency response of the system to preserve stability. The system further includes other methods for detecting imminent instability and compensating, such as detecting the onset of signals within enhancement frequencies characteristic of the onset of instability, and adjusting the gain of frequency response of the system or suppressing the enhanced signals. The system further includes a mechanism for conserving battery life by turning the system off when sound levels are low, or adjusting the power supply to the system to correspond to the current power requirements of the system.

公开(公告)号：EP0861486A1

公开(公告)日：1998-09-02

申请号：EP96938296.0

申请日：1996-11-12

申请人： TECHNOFIRST

发明人： CARME, Christian ,  ROURE, Alain

IPC分类号： G01V1 ,  G10K11

CPC分类号： G10K11/178 ,  G01V1/288 ,  G10K2210/108 ,  G10K2210/3012 ,  G10K2210/3013 ,  G10K2210/3018

摘要： A device for recovering a wanted acoustic signal (Un) from a composite acoustic signal (Mn) including interference components. The device comprises first sensor means (2) for sensing the composite acoustic signal (Mn), second sensor means (16) for sensing, in real time, an acoustic reference signal (Rn) substantially correlated with the interference components (Pn) of the composite acoustic signal (Mn), adaptive filter means (12), and recovery means (6). The coefficients of the filter means (12) are adapted in real time according to an algorithm selected so that the energy of the composite acoustic signal (Mn) is minimised according to the energy of the acoustic reference signal (Rn), until the signal (Sn) from the output (10) of the recovery means (6) substantially corresponds to the wanted acoustic signal (Un) from which the interfering components (Pn) have been selectively removed.

公开(公告)号：EP0705472A1

公开(公告)日：1996-04-10

申请号：EP94922444.0

申请日：1994-06-23

申请人： NOISE CANCELLATION TECHNOLOGIES, INC.

发明人： JONES, Owen

IPC分类号： A61F11 ,  G10K11

CPC分类号： G10K11/17857 ,  A61F2011/145 ,  G10K11/17855 ,  G10K11/17881 ,  G10K11/17885 ,  G10K2210/108 ,  G10K2210/1081 ,  G10K2210/3011 ,  G10K2210/3013 ,  G10K2210/3019 ,  G10K2210/3028 ,  G10K2210/3056 ,  G10K2210/3214 ,  G10K2210/503

摘要： An active noise cancellation system includes a series of features for more effective cancellation, greater reliability, and improved stability. A particular feature adapted for headset systems includes locating a residual microphone radially offset from the centre of a sound generator to detect a signal more similar to that incident upon the eardrum of the user. In addition, an open back headset design includes perforations on the side of the headset instead of the back, so that the perforations are less susceptible to inadvertent blockage. The system also includes a mechanism for detecting changes in the acoustic characteristics of the environment that may be caused, for example, by pressure exerted upon the earpieces, and that may destabilize the cancellation system. The system automatically responds to such changes, for example, by reducing the gain or the frequency response of the system to preserve stability. The system further includes other methods for detecting imminent instability and compensating, such as detecting the onset of signals within enhancement frequencies characteristic of the onset of instability, and adjusting the gain of frequency response of the system or suppressing the enhanced signals. The system further includes a mechanism for conserving battery life by turning the system off when sound levels are low, or adjusting the power supply to the system to correspond to the current power requirements of the system.

公开(公告)号：EP0423172A1

公开(公告)日：1991-04-24

申请号：EP89907611.0

申请日：1989-06-22

申请人： SENSOR ELECTRONICS, INC. ,  LANGBERG, Edwin

发明人： LANGBERG, Edwin ,  CARUSO, F., Gerald

IPC分类号： A61B7 ,  A61F11 ,  G10K11 ,  H04R1 ,  H04R25

CPC分类号： H04R25/453 ,  A61F2011/145 ,  G10K11/178 ,  G10K2210/108 ,  G10K2210/1081 ,  G10K2210/3013 ,  G10K2210/3045 ,  G10K2210/3228

摘要： Improvement in active noise reduction based on a negative feedback electro-acoustical system which consists of an Electronic Earplug seated in the concha fossa combining active and passive noise reduction in the quiet zone at the ear, a bilateral transducer circuit which drives a speaker as an acoustical velocity source, a shunt feedback control filter network which improves stability and increases noise reduction, and a combined input noise-filter/feedback system. A typical application is in a noisy environment for hearing protection and for improved communication capability, e.g., in vehicular communication, telephone, intercom, hearing aids, and stethoscopes.

公开(公告)号：EP0339911A2

公开(公告)日：1989-11-02

申请号：EP89304065.9

申请日：1989-04-24

申请人： THE GENERAL ELECTRIC COMPANY, p.l.c.

发明人： Edwards, John William ,  Dekker, Nicolaas Martinus Johannes

IPC分类号： G10K11/16

CPC分类号： G10K11/178 ,  G10K2210/112 ,  G10K2210/3013 ,  G10K2210/3028 ,  G10K2210/3034 ,  G10K2210/3045 ,  G10K2210/3217 ,  G10K2210/506

摘要： An active noise control system for controlling noise propagated through a duct (1) comprises a first microphone (5) located to receive the propagated noise at a point in a plane perpendicular to the length of the duct. A loudspeaker (6) is located substantially at that plane for introducing sound into the duct. An analog first control circuit (8,9,10,11) is operative in response to the noise received by the first microphone to feed a signal to the loudspeaker such that the sound introduced thereby destructively interferes with the noise at that point. A second microphone (13) is located further downstream to receive residual noise propagated along the duct despite the destructive interference. A second control circuit (14, 15,16,17), responsive to the residual noise received by the second microphone, controls parameters of the analog first control circuit so as to minimise the residual noise. In particular,the first control circuit includes an integrator (9) which has a transfer function which is electrically controlled by the second control circuit.

摘要翻译： 用于控制通过管道（1）传播的噪声的主动噪声控制系统包括第一麦克风（5），其位于在垂直于管道长度的平面中的点处接收传播的噪声。 扬声器（6）基本上位于该平面处，用于将声音引入管道。 模拟第一控制电路（8,9,10,11）响应于由第一麦克风接收的噪声而工作以将信号馈送到扬声器，使得由此引入的声音破坏性地干扰该点处的噪声。 第二麦克风（13）位于下游以接收沿着管道传播的残余噪声，尽管有破坏性的干扰。 响应于由第二麦克风接收的残余噪声的第二控制电路（14,15,16,17）控制模拟第一控制电路的参数，以使残余噪声最小化。 特别地，第一控制电路包括具有由第二控制电路电控制的传递函数的积分器（9）。

公开(公告)号：EP0468610B1

公开(公告)日：1996-02-07

申请号：EP91250205.1

申请日：1991-07-25

申请人： MNC, INC.

发明人： Moseley, William T

IPC分类号： H04R1/10 ,  H04R3/00 ,  G10K11/16

CPC分类号： H04R1/1083 ,  A61F2011/145 ,  B60G2400/61 ,  B60G2800/012 ,  G10K11/178 ,  G10K2210/108 ,  G10K2210/1081 ,  G10K2210/3013 ,  G10K2210/3019 ,  G10K2210/3045 ,  G10K2210/3214 ,  H04R1/1008 ,  H04R3/005 ,  H04R5/033

摘要： A device for performing electroacoustic functions including noise cancellation, communication interface, and headphone functions. The device includes a composite transducer which is connected to a control unit. The composite transducer, which is adapted for use with the human ear, includes at least three transducers, oriented to be substantially coplanar to each other: two oppositely oriented input transducers for converting acoustic waves into electrical signals, and at least one output transducer oriented facing the ear for converting electrical signals into acoustic waves. The control unit includes circuitry for driving the output transducer based on electrical signals from the input transducers with an amplitude and phase to perform the noise cancellation, sound filtering, communication interface, and headphone functions. The input transducer which is oriented facing the ear picks up residual noise present in the ear canal which was not cancelled by the first input transducer to output transducer signal path due to non-ideal frequency and amplitude characteristics. The second input transducer supplies an electrical signal corresponding to the residual noise to the control circuitry to cancel the residual noise. Additionally, the path of acoustic energy from a noise source, through the composite transducer, and to the ear canal can be lengthened by the addition of a baffle around which the acoustic energy must travel.

公开(公告)号：EP0339911A3

公开(公告)日：1990-10-10

申请号：EP89304065.9

申请日：1989-04-24

申请人： THE GENERAL ELECTRIC COMPANY, p.l.c.

发明人： Edwards, John William ,  Dekker, Nicolaas Martinus Johannes

IPC分类号： G10K11/16

CPC分类号： G10K11/178 ,  G10K2210/112 ,  G10K2210/3013 ,  G10K2210/3028 ,  G10K2210/3034 ,  G10K2210/3045 ,  G10K2210/3217 ,  G10K2210/506

摘要： An active noise control system for controlling noise propagated through a duct (1) comprises a first microphone (5) located to receive the propagated noise at a point in a plane perpendicular to the length of the duct. A loudspeaker (6) is located substantially at that plane for introducing sound into the duct. An analog first control circuit (8,9,10,11) is operative in response to the noise received by the first microphone to feed a signal to the loudspeaker such that the sound introduced thereby destructively interferes with the noise at that point. A second microphone (13) is located further downstream to receive residual noise propagated along the duct despite the destructive interference. A second control circuit (14, 15,16,17), responsive to the residual noise received by the second microphone, controls parameters of the analog first control circuit so as to minimise the residual noise. In particular,the first control circuit includes an integrator (9) which has a transfer function which is electrically controlled by the second control circuit.

公开(公告)号：EP0192379A3

公开(公告)日：1987-06-03

申请号：EP86300791

申请日：1986-02-06

申请人： PLESSEY OVERSEAS LIMITED

发明人： Twiney, Robert Christopher

IPC分类号： G10K11/16

CPC分类号： G10K11/178 ,  G10K2210/108 ,  G10K2210/1081 ,  G10K2210/3013 ,  G10K2210/3218

摘要： An active noise reduction arrangement which comprises at least one ear defender or earphone structure which embodies a small noise pick-up microphone and associated noise-cancelling transducer, in which a front cavity defined between the structure and the ear of its wearer when the arrangement is in use is coupled to a further cavity and/or source of low frequency noise-cancellation signals by means of low-pass acoustic filter means.

公开(公告)号：EP0192379A2

公开(公告)日：1986-08-27

申请号：EP86300791.0

申请日：1986-02-06

申请人： Siemens Plessey Electronic Systems Limited

发明人： Twiney, Robert Christopher

IPC分类号： G10K11/16

CPC分类号： G10K11/178 ,  G10K2210/108 ,  G10K2210/1081 ,  G10K2210/3013 ,  G10K2210/3218

摘要： An active noise reduction arrangement which comprises at least one ear defender or earphone structure which embodies a small noise pick-up microphone and associated noise-cancelling transducer, in which a front cavity defined between the structure and the ear of its wearer when the arrangement is in use is coupled to a further cavity and/or source of low frequency noise-cancellation signals by means of low-pass acoustic filter means.

摘要翻译： 一种主动降噪装置，其包括至少一个耳部防护器或耳机结构，其具有小型噪声拾取麦克风和相关联的噪声消除换能器，其中当该装置是布置时，限定在其佩戴者的结构和耳朵之间的前腔 在使用中通过低通声学滤波器装置耦合到另一空腔和/或低频噪声消除信号源。

公开(公告)号：EP0040462A1

公开(公告)日：1981-11-25

申请号：EP81300660.8

申请日：1981-02-18

申请人： BOSE CORPORATION

发明人： Bose, Amar G.

IPC分类号： G10K11/16

CPC分类号： G10K11/178 ,  G10K2210/112 ,  G10K2210/12822 ,  G10K2210/3011 ,  G10K2210/3013 ,  G10K2210/3217

摘要： The noise power perceived in an environment of volume larger than and outside a volume including a source (11) of audible noise is appreciably reduced with an active system that includes an acoustical combiner (13) that combines the noise signal to be reduced with an inversely fed back signal provided by a loudspeaker (14) energized by a controlled frequency selective amplifier (16) that amplifies spectral components to be reduced provided by a microphone (15) near the output of the acoustical combiner (13).

摘要翻译： 在包括可听噪声的源（11）的体积大于和超过音量的环境中感知到的噪声功率被明显地减小，其中主动系统包括组合器（13），声学组合器将要减小的噪声信号 由扬声器（14）提供的反馈信号由受控频率选择放大器（16）激励，该控制频率选择放大器（16）放大由声学组合器（13）的输出附近的麦克风（15）提供的频谱分量。