公开(公告)号：US20060035611A1

公开(公告)日：2006-02-16

申请号：US10917891

申请日：2004-08-13

申请人： Lawrence Connell ,  Yan Cui ,  Poojan Wagh ,  Patrick Rakers

发明人： Lawrence Connell ,  Yan Cui ,  Poojan Wagh ,  Patrick Rakers

IPC分类号： H04B7/00

CPC分类号： H03D7/1441 ,  H03D7/1458 ,  H03D7/1466 ,  H03D2200/0025 ,  H03D2200/0088 ,  H04B1/30

摘要： Method and apparatus are provided for high linearity and low noise communication signal mixing. The apparatus includes a high linearity low noise mixer having an input stage coupled to a switch stage by a series-coupled blocking capacitance and input resistance. The input stage includes a buffer with negative feedback, and the switch stage includes a transistor based switch network connected to an amplifier that has feedback resistance and shunting capacitance. The method includes AC coupling an RF signal, increasing a gain of the RF signal, reducing third-order distortion by negatively feeding-back the RF signal, blocking IM2 generated from said gain increasing step, increasing a second-order input intercept point (IIP2) by attenuating the RF signal across a resistance, and applying a local oscillator input to the RF signal.

摘要翻译： 提供了高线性度和低噪声通信信号混合的方法和装置。 该装置包括具有通过串联耦合的阻塞电容和输入电阻耦合到开关级的输入级的高线性度低噪声混合器。 输入级包括具有负反馈的缓冲器，并且开关级包括连接到具有反馈电阻和分流电容的放大器的基于晶体管的开关网络。 该方法包括AC耦合RF信号，增加RF信号的增益，通过负反馈RF信号减少三阶失真，阻止从所述增益增加步骤产生的IM2，增加二阶输入截点（IIP2 ），通过跨越电阻衰减RF信号，以及将本地振荡器输入施加到RF信号。

公开(公告)号：US20070139103A1

公开(公告)日：2007-06-21

申请号：US11314203

申请日：2005-12-20

申请人： William Roeckner ,  Pallab Midya ,  Patrick Rakers ,  Lawrence Connell ,  Daniel Mavencamp ,  Bradley Stewart

发明人： William Roeckner ,  Pallab Midya ,  Patrick Rakers ,  Lawrence Connell ,  Daniel Mavencamp ,  Bradley Stewart

IPC分类号： H03F3/38

CPC分类号： H03F3/2173 ,  H03F1/305 ,  H03F3/2171 ,  H03F3/72 ,  H03F2200/03 ,  H03F2200/351 ,  H03K17/161

摘要： A closed loop audio amplifier system and method of powering up/down the system without producing audible artifacts are provided. During power up, a prebias voltage is provided to each output connected to a speaker to increase the voltage to a nominal output level. High impedance switches are then driven at a 50% duty cycle. Feedback from the output is supplied to a servo, which is enabled to fine tune the output voltage. Low impedance switches are then driven at a 50% duty cycle at a quarter cycle timing. The order of the feedback loop depends on which of the high or low impedance switches are driven. The prebias voltage is then removed before audio signals to be amplified are supplied to the system. Timing of driving of the switches is programmable. To power down,. essentially the reverse sequence is provided.

摘要翻译： 提供一种闭环音频放大器系统以及在不产生可听见的伪影的情况下对系统加电/下电的方法。 在上电期间，向连接到扬声器的每个输出端提供预偏置电压以将电压增加到额定输出电平。 然后以50％占空比驱动高阻抗开关。 输出端的反馈信号被提供给一个伺服控制器，可以对输出电压进行微调。 然后，在四分之一周期的时间，以50％的占空比驱动低阻抗开关。 反馈环路的顺序取决于驱动高阻抗或低阻抗开关中的哪一个。 然后在将要放大的音频信号提供给系统之前，去除预偏置电压。 开关的驱动时序是可编程的。 断电 基本上提供了相反的顺序。

公开(公告)号：US20050225467A1

公开(公告)日：2005-10-13

申请号：US10819644

申请日：2004-04-07

申请人： Pallab Midya ,  Matthew Miller ,  Patrick Rakers

发明人： Pallab Midya ,  Matthew Miller ,  Patrick Rakers

IPC分类号： H03M1/12 ,  H03M1/34 ,  H03M3/02

CPC分类号： H03M3/00

摘要： A system and method for analog-to-digital conversion using digital pulse width modulation (PWM) is disclosed. The method and system according to the disclosed invention converts an analog input signal to a digital signal in pulse code modulated (PCM) form. The disclosed invention uses a feedback circuit to perform PWM of the analog input signal. The PWM signal is then decimated to obtain the digital signal in PCM form. The system according to the disclosed invention requires lower operating frequency and dissipates lesser power than prior art systems providing the same sampling frequency and resolution. The operation at a lower frequency is achieved by obtaining two samples from every pulse of the PWM signal; the first sample being obtained from the right duty ratio, and the second sample being obtained form the left duty ratio. Further, the disclosed invention has lesser implementation complexity and higher signal-to-noise ratio than prior art.

摘要翻译： 公开了一种使用数字脉宽调制（PWM）进行模数转换的系统和方法。 根据所公开的发明的方法和系统将模拟输入信号转换成脉冲编码调制（PCM）形式的数字信号。 所公开的发明使用反馈电路来执行模拟输入信号的PWM。 然后抽取PWM信号以获得PCM形式的数字信号。 根据所公开的发明的系统需要更低的工作频率并且消耗比提供相同采样频率和分辨率的现有技术系统更小的功率。 通过从PWM信号的每个脉冲获得两个采样来实现较低频率的操作; 从正确的占空比获得第一个样品，并且从左占空比获得第二个样品。 此外，所公开的发明比现有技术具有较小的实现复杂度和更高的信噪比。

公开(公告)号：US06614323B2

公开(公告)日：2003-09-02

申请号：US09995305

申请日：2001-11-27

申请人： Poojan A. Wagh ,  Pallab Midya ,  Patrick Rakers

发明人： Poojan A. Wagh ,  Pallab Midya ,  Patrick Rakers

IPC分类号： H03K700

CPC分类号： H03C3/40

摘要： A device for implementing a method for receiving a complex baseband signal in analog form or in digital form, and providing a pulse modulated signal as a linear modulation of the complex baseband signal is disclosed. First, a complex modulated signal as a function of the complex baseband signal is generated. Second, a bandlimited exponential signal as a function of the complex modulated signal as computed with a truncated Taylor series for an exponential is generated, or a coefficient vector as a function of the complex modulated signal is generated. Finally, a pulse modulated signal as either a function of the bandlimited exponential signal or the coefficient vector is generated.

摘要翻译： 公开了一种用于实现用于以模拟形式或数字形式接收复基带信号的方法，并提供脉冲调制信号作为复基带信号的线性调制的装置。 首先，生成作为复基带信号的函数的复调制信号。 第二，产生作为用指数的截断泰勒级数计算的复调制信号的函数的带限指数信号，或者产生作为复调制信号的函数的系数向量。 最后，产生作为带限指数信号或系数矢量的函数的脉冲调制信号。

公开(公告)号：US06587010B2

公开(公告)日：2003-07-01

申请号：US09995123

申请日：2001-11-27

申请人： Poojan A. Wagh ,  Pallab Midya ,  Patrick Rakers

发明人： Poojan A. Wagh ,  Pallab Midya ,  Patrick Rakers

IPC分类号： H03B104

CPC分类号： H03K7/00 ,  H04B1/04

摘要： A modulated signal source for implementing A modulated signal method of a generating a modulated signal having a radio frequency based upon a linear mixing of signals is disclosed. An in-phase pulse signal modulator of the modulated signal source provides an in-phase pulse modulated signal in response to a reception of a baseband in-phase signal and an in-phase clock signal with the in-phase clock signal and the in-phase pulse modulated signal being synchronized. A quadrature pulse signal modulator of the modulated signal source provides a quadrature pulse modulated signal in response to a reception of a baseband quadrature signal and a quadrature clock signal with the quadrature clock signal and the quadrature pulse modulated signal being synchronized. A switch signal generator of the modulated signal source generates an in-phase switch signal and a quadrature switch signal in response to a reception of the in-phase clock signal, the in-phase pulse modulated signal, the quadrature clock signal, and the quadrature pulse modulated signal. The in-phase clock signal and the in-phase switch signal are synchronized, and the quadrature clock signal and the quadrature switch signal are synchronized. A radio frequency signal generator of the modulated signal source provides one or more modulated signals having a radio frequency in response to either a reception the in-phase switch signal and the quadrature phase signal, or a reception of a switch signal as a function of the in-phase switch signal and the quadrature phase signal.

公开(公告)号：US06549085B1

公开(公告)日：2003-04-15

申请号：US09995122

申请日：2001-11-27

申请人： Poojan A. Wagh ,  Pallab Midya ,  Patrick Rakers

发明人： Poojan A. Wagh ,  Pallab Midya ,  Patrick Rakers

IPC分类号： H03K708

CPC分类号： H03K7/10

摘要： A device for implementing a method for generating a pulse width modulated signal based upon a natural sampling technique is disclosed. First, a complex baseband signal is received by the device. Second, the device computes a first pulse edge vector and a second pulse edge vector as a function of the baseband signal. Third, the device computes a first set of natural sampling points as a function of the first pulse edge vector and computes a second set of natural sampling points as a function of the second pulse edge vector. These computations can involve one or more detections of a jump k&pgr; within the first pulse edge vector and/or the second pulse edge vector. Finally, the pulse width modulated signal is generated with pulse edges corresponding to the first set of natural sampling points and the second set of natural sampling points.

摘要翻译： 公开了一种用于实现基于自然采样技术产生脉宽调制信号的方法的装置。 首先，设备接收到复杂的基带信号。 第二，该装置计算作为基带信号的函数的第一脉冲边缘向量和第二脉冲边缘向量。 第三，设备根据第一脉冲边缘向量计算第一组自然采样点，并计算作为第二脉冲边缘向量的函数的第二组自然采样点。 这些计算可涉及在第一脉冲边缘向量和/或第二脉冲边缘向量内的跳转kpi的一个或多个检测。 最后，利用对应于第一组自然采样点和第二组自然采样点的脉冲边缘产生脉宽调制信号。