公开(公告)号：US07518444B2

公开(公告)日：2009-04-14

申请号：US11672191

申请日：2007-02-07

Applicant: Jack B. Andersen ,  Peter G. Craven ,  Daniel L. W. Chieng ,  Michael A. Kost

Inventor： Jack B. Andersen ,  Peter G. Craven ,  Daniel L. W. Chieng ,  Michael A. Kost

IPC: H03F3/38

CPC classification number: H03F3/2171 ,  H03F1/32 ,  H03F1/52 ,  H03F1/523 ,  H03F3/2175 ,  H03F2200/03 ,  H03F2200/153 ,  H03F2200/351

Abstract: Systems and methods for improving the stability of feedback and/or feed-forward subsystems in digital amplifiers. One embodiment comprises a digital pulse width modulation (PWM) controller. The controller includes an input for receiving a digital audio input signal and is configured to generate a PWM output signal based on the input signal at an output. The controller also has control inputs for receiving external audio correction signals such as feedback and power supply feed-forward signals. The controller has correction circuitry for processing the received external control signals and modifying the input signal based on these signals. Fault detectors monitor fault conditions at various locations within the correction circuitry, and a protection control unit receives fault signals from the fault detectors and modifies operation of the controller in response to the fault signals.

Abstract translation: 用于提高数字放大器中反馈和/或前馈子系统稳定性的系统和方法。 一个实施例包括数字脉宽调制（PWM）控制器。 控制器包括用于接收数字音频输入信号的输入端，并且被配置为基于输出端的输入信号产生PWM输出信号。 控制器还具有用于接收外部音频校正信号（如反馈和电源前馈信号）的控制输入。 该控制器具有校正电路，用于处理所接收的外部控制信号，并根据这些信号修改输入信号。 故障检测器监视校正电路内的各个位置的故障状况，保护控制单元从故障检测器接收故障信号，并根据故障信号修改控制器的操作。

公开(公告)号：US08406436B2

公开(公告)日：2013-03-26

申请号：US12444628

申请日：2007-10-05

Applicant: Peter G. Craven ,  Malcolm Law ,  Chris Travis

Inventor： Peter G. Craven ,  Malcolm Law ,  Chris Travis

IPC: H04R25/00

CPC classification number: H04S3/00 ,  H04R5/027 ,  H04S2400/15 ,  H04S2420/11

Abstract: A sound capture device comprises a symmetric microphone array that includes non-radially-oriented directional sensors (101). The device typically derives a spherical harmonic representation of the incident sound field, and affords higher signal-to-noise ratios and better directional fidelity than prior arrays, across a wide range of audio frequencies.

Abstract translation: 声音捕获装置包括包括非径向定向传感器（101）的对称麦克风阵列。 器件通常导出入射声场的球面谐波表示，并且在广泛的音频范围内提供比现有阵列更高的信噪比和更好的方向保真度。

公开(公告)号：US20070170984A1

公开(公告)日：2007-07-26

申请号：US11626569

申请日：2007-01-24

Applicant: Jack B. Andersen ,  Peter G. Craven

Inventor： Jack B. Andersen ,  Peter G. Craven

IPC: H03F3/38

CPC classification number: H03F3/217 ,  H03F1/3264 ,  H03F3/2173 ,  H03F2200/03 ,  H03F2200/114 ,  H03F2200/351 ,  H03F2201/3236 ,  H03K17/162 ,  H03K17/6871

Abstract: Systems and methods in which an ultrasonic signal is introduced into an audio signal before the audio signal is amplified by a switching amplifier. The added ultrasonic signal (e.g., a tone at half the amplifier's switching frequency) shifts the signals input to a set of power switches so that they do not switch nearly simultaneously. The ultrasonic signal causes the output current to be well defined to eliminate dead time distortion at low signal levels. Adding the tone ultrasonic signal causes the distortion to shift to an amplitude greater than zero. Signals that exceed this amplitude will experience the distortion, but the distortion will be less noticeable than in lower-amplitude signals. Signals that do not exceed this amplitude will not experience the distortion at all. Adding an ultrasonic signal may also draw energy away from the switch frequency and its harmonics to interference with AM radio reception.

Abstract translation: 在音频信号被开关放大器放大之前，将超声波信号引入到音频信号中的系统和方法。 增加的超声波信号（例如，放大器开关频率的一半处的音调）将输入的信号移动到一组电源开关，使得它们几乎不同时切换。 超声波信号使得输出电流被良好地定义，以消除低信号电平下的死区失真。 增加音调超声信号会导致失真转移到大于零的幅度。 超过该幅度的信号将经历失真，但是失真比在较低幅度信号中更不明显。 不超过此幅度的信号根本不会出现失真。 添加超声波信号也可能会从开关频率及其谐波中吸收能量，从而干扰AM无线电接收。

公开(公告)号：US06664913B1

公开(公告)日：2003-12-16

申请号：US08952743

申请日：1999-05-17

Applicant: Peter G. Craven ,  Michael A. Gerzon

Inventor： Peter G. Craven ,  Michael A. Gerzon

IPC: H03M100

CPC classification number: H03M7/3046

Abstract: In a method of lossless processing of an integer value signal in a prediction filter which includes a quantiser, a numerator of the prediction filter is implemented prior to the quantiser and a denominator of the prediction filter is implemented recursively around the quantiser to reduce the peak data rate of an output signal. In the lossless processor, at each sample instant, an input to the quantiser is jointly responsive to a first sample value of a signal input to the prediction filter, a second sample value of a signal input to the prediction filter at a previous sample instant, and an output value of the quantiser at a previous sample incident. In a preferred embodiment, the prediction filter includes noise shaping for affecting the output of the quantiser.

Abstract translation: 在包括量化器的预测滤波器中对整数值信号进行无损处理的方法中，在量化器之前实现预测滤波器的分子，并且在量化器周围递归地实现预测滤波器的分母以减少峰值数据 输出信号的速率。 在无损处理器中，在每个采样时刻，对量化器的输入共同响应输入到预测滤波器的信号的第一采样值，在先前采样时刻输入到预测滤波器的信号的第二采样值， 以及在之前的采样事件处的量化器的输出值。 在优选实施例中，预测滤波器包括用于影响量化器的输出的噪声整形。

公开(公告)号：US07812666B2

公开(公告)日：2010-10-12

申请号：US12542634

申请日：2009-08-17

Applicant: Daniel L. W. Chieng ,  Peter G. Craven ,  Michael A. Kost ,  Jack B. Andersen ,  Larry E. Hand ,  Wilson E. Taylor

Inventor： Daniel L. W. Chieng ,  Peter G. Craven ,  Michael A. Kost ,  Jack B. Andersen ,  Larry E. Hand ,  Wilson E. Taylor

IPC: H03F3/68

CPC classification number: H03F3/217

Abstract: A low delay corrector (LDC) unit includes a non-linear function generator and a filter. The nonlinear function generator receives a first signal and outputs a second signal in dependence on the first signal and a transfer function of the nonlinear function generator. The filter is fed in dependence on the second signal output by the nonlinear function generator. The first signal received by the nonlinear function generator is derived in dependence on an input signal provided to an input of the LDC unit and an output of the filter. An output of the LDC unit is derived in dependence on the first signal received by the nonlinear function generator and the second signal output by the nonlinear function generator.

Abstract translation: 低延迟校正器（LDC）单元包括非线性函数发生器和滤波器。 非线性函数发生器接收第一信号并根据第一信号和非线性函数发生器的传递函数输出第二信号。 滤波器根据由非线性函数发生器输出的第二信号进给。 根据提供给LDC单元的输入的输入信号和滤波器的输出，导出由非线性函数发生器接收到的第一信号。 根据由非线性函数发生器接收到的第一信号和由非线性函数发生器输出的第二信号，导出LDC单元的输出。

公开(公告)号：US07728658B2

公开(公告)日：2010-06-01

申请号：US11782702

申请日：2007-07-25

Applicant: Jack B. Andersen ,  Peter G. Craven ,  Michael A. Kost ,  Daniel L. W. Chieng ,  Larry E. Hand ,  Wilson E. Taylor

Inventor： Jack B. Andersen ,  Peter G. Craven ,  Michael A. Kost ,  Daniel L. W. Chieng ,  Larry E. Hand ,  Wilson E. Taylor

IPC: H03F3/38 ,  H03F1/30

CPC classification number: H03F1/3258 ,  H03F1/26 ,  H03F1/3241 ,  H03F3/217

Abstract: Systems and methods for performance improvements in digital switching amplifiers using low-pass filtering to reduce noise and distortion. In one embodiment, a digital pulse width modulation (PWM) amplifier includes a signal processing plant configured to receive and process an input audio signal. The amplifier also includes a low-pass filter configured to filter audio signals output by the plant. The filtered output of the plant is added to the input audio signal as feedback. The plant may consist of a modulator and power switch, a noise shaper, or any other type of plant. An analog-to-digital converter (ADC) may be provided to convert the output audio signal to a digital signal. Filtering may be implemented before or after the ADC, and a decimator may be placed after the ADC if it is an oversampling ADC.

Abstract translation: 使用低通滤波技术降低噪声和失真的数字开关放大器性能改进的系统和方法。 在一个实施例中，数字脉宽调制（PWM）放大器包括被配置为接收和处理输入音频信号的信号处理设备。 放大器还包括一个低通滤波器，用于滤除工厂输出的音频信号。 工厂的滤波输出作为反馈被添加到输入音频信号。 该设备可以由调制器和电源开关，噪声整形器或任何其它类型的设备组成。 可以提供模数转换器（ADC）以将输出音频信号转换为数字信号。 可以在ADC之前或之后实现滤波，如果ADC是过采样ADC，则可以在ADC之后放置抽取器。

公开(公告)号：US20070183490A1

公开(公告)日：2007-08-09

申请号：US11672191

申请日：2007-02-07

Applicant: Jack B. Andersen ,  Peter G. Craven ,  Daniel L. W. Chieng ,  Michael A. Kost

Inventor： Jack B. Andersen ,  Peter G. Craven ,  Daniel L. W. Chieng ,  Michael A. Kost

IPC: H03K9/08

CPC classification number: H03F3/2171 ,  H03F1/32 ,  H03F1/52 ,  H03F1/523 ,  H03F3/2175 ,  H03F2200/03 ,  H03F2200/153 ,  H03F2200/351

Abstract: Systems and methods for improving the stability of feedback and/or feed-forward subsystems in digital amplifiers. One embodiment comprises a digital pulse width modulation (PWM) controller. The controller includes an input for receiving a digital audio input signal and is configured to generate a PWM output signal based on the input signal at an output. The controller also has control inputs for receiving external audio correction signals such as feedback and power supply feed-forward signals. The controller has correction circuitry for processing the received external control signals and modifying the input signal based on these signals. Fault detectors monitor fault conditions at various locations within the correction circuitry, and a protection control unit receives fault signals from the fault detectors and modifies operation of the controller in response to the fault signals.

Abstract translation: 用于提高数字放大器中反馈和/或前馈子系统稳定性的系统和方法。 一个实施例包括数字脉宽调制（PWM）控制器。 控制器包括用于接收数字音频输入信号的输入端，并且被配置为基于输出端的输入信号产生PWM输出信号。 控制器还具有用于接收外部音频校正信号（如反馈和电源前馈信号）的控制输入。 该控制器具有校正电路，用于处理所接收的外部控制信号，并根据这些信号修改输入信号。 故障检测器监视校正电路内的各个位置的故障状况，保护控制单元从故障检测器接收故障信号，并根据故障信号修改控制器的操作。

公开(公告)号：US5511129A

公开(公告)日：1996-04-23

申请号：US74837

申请日：1993-08-03

Applicant: Peter G. Craven ,  Michael A. Gerzon

Inventor： Peter G. Craven ,  Michael A. Gerzon

IPC: H03G5/16 ,  H03H21/00 ,  H04R3/04 ,  H04R29/00 ,  H04S7/00 ,  H03G5/00

CPC classification number: H04S7/307 ,  H03G5/165 ,  H03H21/0012 ,  H04R3/04 ,  H04S7/305 ,  H04R29/001 ,  H04S7/301 ,  H04S7/40

Abstract: A prefilter (5) for an audio system comprising a loudspeaker (1) in a room (2), which corrects both amplitude and phase errors due to the loudspeaker (1) by a linear phase correction filter response and corrects the amplitude response of the room (2) whilst introducing the minimum possible amount of extra phase distortion by employing a minimum phase correction filter stage. A test signal generator (8) generates a signal comprising a periodic frequency sweep with a greater phase repetition period than the frequency repetition period. A microphone (7) positioned at various points in the room (2) measures the audio signal processed by the room (2) and loudspeaker (1), and a coefficient calculator (6) (e.g. a digital signal processor device) derives the signal response of the room and thereby a requisite minimum phase correction to be cascaded with the linear phase correction already calculated for the loudspeaker (1). Filter (5) may comprise the same digital signal processor as the coefficient calculator (6). Applications in high fidelity audio reproduction, and in car stereo reproduction.

Abstract translation: PCT No.PCT / GB91 / 02200 Sec。 371日期1993年8月3日 102（e）日期1993年8月3日PCT 1991年12月11日PCT PCT。 WO92 / 10876BC出版物 日期：1992年6月25日。一种用于音频系统的预滤波器（5），包括在房间（2）中的扬声器（1），其通过线性相位校正滤波器响应来校正由扬声器（1）引起的幅度和相位误差 并且通过采用最小相位校正滤波器级来引入最小可能的额外相位失真量来校正房间（2）的振幅响应。 测试信号发生器（8）产生包括具有比频率重复周期更大的相位重复周期的周期性频率扫描的信号。 定位在房间（2）中的各个点处的麦克风（7）测量由房间（2）和扬声器（1）处理的音频信号，并且系数计算器（6）（例如数字信号处理器设备）导出信号 响应室，从而与已经为扬声器（1）计算出的线性相位校正级联进行必要的最小相位校正。 滤波器（5）可以包括与系数计算器（6）相同的数字信号处理器。 应用于高保真音频再现和汽车立体声再现。

公开(公告)号：US20100142732A1

公开(公告)日：2010-06-10

申请号：US12444628

申请日：2007-10-05

Applicant: Peter G. Craven ,  Malcolm Law ,  Chris Travis

Inventor： Peter G. Craven ,  Malcolm Law ,  Chris Travis

IPC: H04R25/00

CPC classification number: H04S3/00 ,  H04R5/027 ,  H04S2400/15 ,  H04S2420/11

Abstract: A sound capture device comprises a symmetric microphone array that includes non-radially-oriented directional sensors (101). The device typically derives a spherical harmonic representation of the incident sound field, and affords higher signal-to-noise ratios and better directional fidelity than prior arrays, across a wide range of audio frequencies.

Abstract translation: 声音捕获装置包括包括非径向定向传感器（101）的对称麦克风阵列。 器件通常导出入射声场的球面谐波表示，并且在广泛的音频范围内提供比现有阵列更高的信噪比和更好的方向保真度。

公开(公告)号：US07649410B2

公开(公告)日：2010-01-19

申请号：US11626569

申请日：2007-01-24

Applicant: Jack B. Andersen ,  Peter G. Craven

Inventor： Jack B. Andersen ,  Peter G. Craven

IPC: H03F3/38

CPC classification number: H03F3/217 ,  H03F1/3264 ,  H03F3/2173 ,  H03F2200/03 ,  H03F2200/114 ,  H03F2200/351 ,  H03F2201/3236 ,  H03K17/162 ,  H03K17/6871

Abstract: Systems and methods in which an ultrasonic signal is introduced into an audio signal before the audio signal is amplified by a switching amplifier. The added ultrasonic signal (e.g., a tone at half the amplifier's switching frequency) shifts the signals input to a set of power switches so that they do not switch nearly simultaneously. The ultrasonic signal causes the output current to be well defined to eliminate dead time distortion at low signal levels. Adding the tone ultrasonic signal causes the distortion to shift to an amplitude greater than zero. Signals that exceed this amplitude will experience the distortion, but the distortion will be less noticeable than in lower-amplitude signals. Signals that do not exceed this amplitude will not experience the distortion at all. Adding an ultrasonic signal may also draw energy away from the switch frequency and its harmonics to interference with AM radio reception.

Abstract translation: 在音频信号被开关放大器放大之前，将超声波信号引入到音频信号中的系统和方法。 增加的超声波信号（例如，放大器开关频率的一半处的音调）将输入的信号移动到一组电源开关，使得它们几乎不同时切换。 超声波信号使得输出电流被良好地定义，以消除低信号电平下的死区失真。 增加音调超声信号会导致失真转移到大于零的幅度。 超过该幅度的信号将经历失真，但是失真比在较低幅度信号中更不明显。 不超过此幅度的信号根本不会出现失真。 添加超声波信号也可能会从开关频率及其谐波中吸收能量，从而干扰AM无线电接收。