公开(公告)号：US09392364B1

公开(公告)日：2016-07-12

申请号：US13968013

申请日：2013-08-15

Applicant: Cirrus Logic, Inc.

Inventor： Ali Abdollahzadeh Milani ,  Antonio John Miller

IPC: H04R3/00

CPC classification number: H04R3/002 ,  H04R3/00 ,  H04R2410/05 ,  H04R2499/11

Abstract: A processing circuit may implement an adaptive filter having a response that generates an anti-noise signal from a reference microphone signal, one or more filters for modeling an electro-acoustic path of the anti-noise signal from a location of an error microphone to an eardrum of a listener and having a response that generates a filtered reference microphone signal from the reference microphone signal, one or more filters for modeling an acoustic path of ambient audio sounds from the location of the error microphone to the eardrum and having a response that generates a synthesized playback corrected error signal based on the error microphone signal, wherein the synthesized playback corrected error signal is indicative of ambient audio sounds present at the eardrum, and a coefficient control block that shapes the response of the adaptive filter in conformity with the filtered reference microphone signal and the synthesized playback corrected error signal by adapting the response of the adaptive filter to minimize the ambient audio sounds in the synthesized playback corrected error signal.

Abstract translation: 处理电路可以实现具有从参考麦克风信号产生抗噪声信号的响应的自适应滤波器，用于将来自误差麦克风的位置的抗噪声信号的电声路径建模到一个或多个滤波器的一个或多个滤波器 收听者的鼓膜，并具有从参考麦克风信号产生滤波的参考麦克风信号的响应，一个或多个滤波器，用于将环境音频声音的声学路径从误差麦克风的位置建模到鼓膜，并且具有产生的响应 基于所述误差麦克风信号的合成回放校正误差信号，其中所述合成重放校正误差信号指示在所述鼓膜处存在的环境音频声音，以及系数控制块，其根据所述经滤波的参考对所述自适应滤波器的响应进行整形 麦克风信号和合成回放校正误差信号 e自适应滤波器，以最小化合成回放校正误差信号中的环境音频声音。

公开(公告)号：US09324311B1

公开(公告)日：2016-04-26

申请号：US14210537

申请日：2014-03-14

Applicant: Cirrus Logic, Inc.

Inventor： Ali Abdollahzadeh Milani ,  Jeffrey Alderson ,  Gautham Devendra Kamath ,  Yang Lu

IPC: H03B29/00 ,  G10K11/16

CPC classification number: G10K11/16 ,  G10K11/178 ,  G10K11/17835 ,  G10K11/17881 ,  G10K2210/1081 ,  G10K2210/3016 ,  G10K2210/3028 ,  G10K2210/3045 ,  G10K2210/3054

Abstract: An adaptive noise canceling (ANC) circuit adaptively generates an anti-noise signal from that is injected into the speaker or other transducer output to cause cancellation of ambient audio sounds. At least one microphone provides an error signal indicative of the noise cancellation at the transducer, and the coefficients of the adaptive filter are adapted to minimize the error signal. In order to prevent improper adaptation or instabilities in one or both of the adaptive filters, spikes are detected in the error signal by comparing the error signal to a threshold ambient noise average. Therefore, if the magnitude of the coefficient error is greater than a threshold value for an update, the update is skipped. Alternatively the step size of the updates may be reduced.

Abstract translation: 自适应噪声消除（ANC）电路自适应地产生从其被注入扬声器或其它换能器输出中的抗噪声信号，以引起环境声音的消除。 至少一个麦克风提供指示换能器处的噪声消除的误差信号，并且自适应滤波器的系数适于使误差信号最小化。 为了防止一个或两个自适应滤波器中的不适当的适应或不稳定性，通过将误差信号与阈值环境噪声平均值进行比较，在误差信号中检测到峰值。 因此，如果系数误差的大小大于更新的阈值，则跳过更新。 或者，可以减少更新的步长。

公开(公告)号：US09107010B2

公开(公告)日：2015-08-11

申请号：US13762504

申请日：2013-02-08

Applicant: Cirrus Logic, Inc.

Inventor： Ali Abdollahzadeh Milani

IPC: H04R29/00 ,  H03G3/00 ,  G10L21/0224 ,  G10K11/178

CPC classification number: H04R29/00 ,  G10K11/178 ,  G10K2210/108 ,  G10K2210/3023 ,  G10L21/0216 ,  G10L21/0224 ,  G10L2021/02165 ,  H04R29/004

Abstract: An RMS detector uses the concept of the k-NN (classifying using nearest neighbors)—algorithm in order to obtain RMS values. A rms detector using first-order regressor with a variable smoothing factor is modified to penalize samples from center of data in order to obtain RMS values. Samples which vary greatly from the background noise levels, such as speech, scratch, wind and other noise spikes, are dampened in the RMS calculation. When background noise changes, the system will track the changes in background noise and include the changes in the calculation of the corrected RMS value. A minimum tracker runs more often (e.g. two or three times) than the rate as in prior art detectors and methods, tracks the minimum rms value, which is to compute a normalized distance value, which in turn is used to normalize the smoothing factor. From this data, a corrected or revised RMS value is determined as the function of the previous RMS value multiplied by one minus the smoothing factor plus the smooth factor times the minimum rms value to output the corrected RMS for the present invention. The rms value is used to generate a reset signal for the minimum tracker and is used to avoid deadlock in the tracker, for example, when the background signal increases/decreases over time.

Abstract translation: RMS检测器使用k-NN（使用最近邻）分类的算法 - 算法来获得RMS值。 使用具有可变平滑因子的一阶回归器的有效值检测器被修改以惩罚来自数据中心的样本，以获得RMS值。 在RMS计算中，与背景噪声水平差异很大的样本（如语音，划痕，风和其他噪声尖峰）都会受到影响。 当背景噪声改变时，系统将跟踪背景噪声的变化，并包括校正RMS值的计算中的变化。 最小跟踪器比现有技术的检测器和方法中的速率更频繁（例如两次或三次），跟踪最小均方根值，其是计算归一化距离值，其又被用于归一化平滑因子。 根据该数据，校正或修正的RMS值被确定为先前RMS值乘以1的函数减去平滑因子加上平滑因子乘以最小均方根值，以输出本发明的校正RMS。 均方根值用于产生最小跟踪器的复位信号，并用于避免跟踪器中的死锁，例如当背景信号随时间增加/减小时。

公开(公告)号：US20140270222A1

公开(公告)日：2014-09-18

申请号：US13968007

申请日：2013-08-15

Applicant: Cirrus Logic, Inc.

Inventor： Jon D. Hendrix ,  Jeffrey Alderson ,  Ali Abdollahzadeh Milani ,  Dayong Zhou ,  Yang Lu

IPC: H04R3/00

CPC classification number: H04R1/1083 ,  G10K11/178 ,  G10K2210/1081 ,  G10K2210/3019 ,  G10K2210/3028 ,  H04R1/24 ,  H04R3/005 ,  H04R3/12 ,  H04R2410/05 ,  H04R2460/01

Abstract: A personal audio device including multiple output transducers for reproducing different frequency bands of a source audio signal, includes an adaptive noise canceling (ANC) circuit that adaptively generates an anti-noise signal for each of the transducers from at least one microphone signal that measures the ambient audio to generate anti-noise signals. The anti-noise signals are generated by separate adaptive filters such that the anti-noise signals cause substantial cancellation of the ambient audio at their corresponding transducers. The use of separate adaptive filters provides low-latency operation, since a crossover is not needed to split the anti-noise into the appropriate frequency bands. The adaptive filters can be implemented or biased to generate anti-noise only in the frequency band corresponding to the particular adaptive filter. The anti-noise signals are combined with source audio of the appropriate frequency band to provide outputs for the corresponding transducers.

Abstract translation: 包括用于再现源音频信号的不同频带的多个输出换能器的个人音频设备包括自适应噪声消除（ANC）电路，该自适应噪声消除（ANC）电路从至少一个麦克风信号自适应地生成每个换能器的抗噪声信号，该麦克风信号测量 环境音频产生抗噪声信号。 抗噪声信号由单独的自适应滤波器产生，使得抗噪声信号在其相应的换能器处引起环境音频的实质消除。 使用单独的自适应滤波器提供低等待时间操作，因为不需要交叉来将抗噪声分解成适当的频带。 可以实现或偏置自适应滤波器以仅在对应于特定自适应滤波器的频带中产生抗噪声。 抗噪声信号与适当频带的源音频组合，为相应的换能器提供输出。

公开(公告)号：US20140226827A1

公开(公告)日：2014-08-14

申请号：US13762504

申请日：2013-02-08

Applicant: CIRRUS LOGIC, INC.

Inventor： Ali Abdollahzadeh Milani

IPC: H04R29/00

CPC classification number: H04R29/00 ,  G10K11/178 ,  G10K2210/108 ,  G10K2210/3023 ,  G10L21/0216 ,  G10L21/0224 ,  G10L2021/02165 ,  H04R29/004

Abstract: An RMS detector uses the concept of the k-NN (classifying using nearest neighbors)-algorithm in order to obtain RMS values. A rms detector using first-order regressor with a variable smoothing factor is modified to penalize samples from center of data in order to obtain RMS values. Samples which vary greatly from the background noise levels, such as speech, scratch, wind and other noise spikes, are dampened in the RMS calculation. When background noise changes, the system will track the changes in background noise and include the changes in the calculation of the corrected RMS value. A minimum tracker runs more often (e.g. two or three times) than the rate as in prior art detectors and methods, tracks the minimum rms value, which is to compute a normalized distance value, which in turn is used to normalize the smoothing factor. From this data, a corrected or revised RMS value is determined as the function of the previous RMS value multiplied by one minus the smoothing factor plus the smooth factor times the minimum rms value to output the corrected RMS for the present invention. The rms value is used to generate a reset signal for the minimum tracker and is used to avoid deadlock in the tracker, for example, when the background signal increases/decreases over time.

Abstract translation: RMS检测器使用k-NN（使用最近邻）分类的算法 - 算法来获得RMS值。 使用具有可变平滑因子的一阶回归器的有效值检测器被修改以惩罚来自数据中心的样本，以获得RMS值。 在RMS计算中，与背景噪声水平差异很大的样本（如语音，划痕，风和其他噪声尖峰）都会受到影响。 当背景噪声改变时，系统将跟踪背景噪声的变化，并包括校正RMS值的计算中的变化。 最小跟踪器比现有技术的检测器和方法中的速率更频繁（例如两次或三次），跟踪最小均方根值，其是计算归一化距离值，其又被用于归一化平滑因子。 根据该数据，校正或修正的RMS值被确定为先前RMS值乘以1的函数减去平滑因子加上平滑因子乘以最小均方根值，以输出本发明的校正RMS。 均方根值用于产生最小跟踪器的复位信号，并用于避免跟踪器中的死锁，例如当背景信号随时间增加/减小时。