公开(公告)号：US08422409B2

公开(公告)日：2013-04-16

申请号：US12895143

申请日：2010-09-30

申请人： Hangwei Guo ,  Yifeng Zhang ,  Peiqi Xuan

发明人： Hangwei Guo ,  Yifeng Zhang ,  Peiqi Xuan

IPC分类号： H04B7/005 ,  H04B1/44 ,  H04W4/00 ,  H04J3/02

CPC分类号： H04B1/40 ,  H04B1/034

摘要： A device and method of duplex audio communication over a broadcast channel are disclosed. Low-power transmission over a broadcast channel is permissible for personal use as long as the transmitted power level is below a level allowed by respective regulatory. For example, low-power FM transmitter can be used to provide a wireless audio link between two audio devices. One such application scenario is a wireless speakerphone used as an audio extension from a cellphone for group conference purposes. Such applications face issues of potential interference from other users of the same channel and the need of manually selecting and tuning a pair of channels. The device and method disclosed in the present invention use the clear channel technique to automatically select an un-occupied channel for the transmit side and utilizes an identification embedded in a sub-channel to allow the receiver to automatically tune to the channel used by the transmitter. The clear channels may be determined by respective transceivers or determined by a master transceiver.

摘要翻译： 公开了一种通过广播信道进行双工音频通信的设备和方法。 只要发射功率水平低于相关监管机构允许的水平，就可以在广播频道上进行低功率传输。 例如，低功率FM发射机可用于在两个音频设备之间提供无线音频链路。 一种这样的应用场景是用作用于组会议目的的手机的音频扩展的无线扬声器。 这样的应用程序面临来自相同信道的其他用户的潜在干扰的问题以及手动选择和调谐一对信道的需要。 在本发明中公开的设备和方法使用清晰的信道技术来自动选择用于发射侧的未占用信道，并利用嵌入在子信道中的标识来允许接收机自动调谐到由发射机使用的信道 。 清除信道可以由相应的收发器确定或由主收发器确定。

公开(公告)号：US08301086B2

公开(公告)日：2012-10-30

申请号：US12698154

申请日：2010-02-02

申请人： John B. Groe ,  Michael Noane Farias

发明人： John B. Groe ,  Michael Noane Farias

IPC分类号： H04B1/02 ,  H04B1/04 ,  H03C1/52 ,  H01Q11/12

CPC分类号： H03D7/165 ,  H04B1/04 ,  H04B2001/0491

摘要： Apparatus and methods for providing transmit signals in polar transmitters are described. A modulation signal may be provided from a VCO to low noise and low power signal paths and selectively combined based on a desired output power level. CMOS and CML divider circuits may be used to implement the low noise and low power signal paths respectively, and logic may be provided to select desired signals from the low noise and low power signal stages based on the desired output power level.

摘要翻译： 描述了在极性发射机中提供发射信号的装置和方法。 调制信号可以从VCO提供到低噪声和低功率信号路径，并且基于期望的输出功率电平有选择地组合。 可以使用CMOS和CML分频器电路来分别实现低噪声和低功率信号路径，并且可以提供逻辑以基于期望的输出功率电平从低噪声和低功率信号级选择期望的信号。

公开(公告)号：US08300732B1

公开(公告)日：2012-10-30

申请号：US12465581

申请日：2009-05-13

申请人： Mark Magdaleno ,  John B. Groe

发明人： Mark Magdaleno ,  John B. Groe

IPC分类号： H04L25/06 ,  H03D1/04 ,  H04B1/12

CPC分类号： H04L25/063 ,  H04B1/30

摘要： Apparatus and methods for removing dc offsets in feedback loops such as may be used in communication circuits are disclosed. A comparator may be used to sample the output of the feedback loop, with the comparator output applied to a DSP module. The DSP module is configured to determine a dc offset in the output signal and generate an offset correction signal, which may then be applied to the input of the feedback loop to adjust the de offset.

摘要翻译： 公开了用于消除诸如可用于通信电路的反馈回路中的直流偏置的装置和方法。 比较器可用于对反馈回路的输出进行采样，将比较器输出应用于DSP模块。 DSP模块被配置为确定输出信号中的直流偏移并产生偏移校正信号，然后将其补偿到反馈回路的输入端以调整偏移。

公开(公告)号：US08237485B2

公开(公告)日：2012-08-07

申请号：US12872371

申请日：2010-08-31

申请人： Hao Meng ,  Peiqi Xuan

发明人： Hao Meng ,  Peiqi Xuan

IPC分类号： G06F1/04

CPC分类号： G06F1/06 ,  H03K23/50

摘要： A system and method of clock generation to provide divided-by-2 clocks with prescribed phase shifts are disclosed. In a communication system with high-order harmonic mixing, the system requires LO signals with a set of prescribed phase shifts, such as 0°, 45°, 90°, and 135°, or 0°, 60° and 120°. Often, the clock generation system involves a divide-by-2 divider to derive the clock signals with the prescribed phase shifts. In a conventional implementation of the divide-by-2 divider, the system is subject to phase uncertainty in the output signal. Accordingly, a system comprises multiple latch pairs and respective differential clocks are used to generate the clocks with the set of correct prescribed phase shifts.

摘要翻译： 公开了一种提供具有规定相移的二分之一秒钟的时钟产生系统和方法。 在具有高次谐波混合的通信系统中，系统需要具有一定规定相移的LO信号，例如0°，45°，90°和135°，或0°，60°和120°。 通常，时钟发生系统涉及一个除以2的分频器，以规定的相移导出时钟信号。 在2分频器的传统实现中，系统在输出信号中受到相位不确定性的影响。 因此，系统包括多个锁存器对，并且使用相应的差分时​​钟来产生具有正确规定相移集合的时钟。

公开(公告)号：US08213890B2

公开(公告)日：2012-07-03

申请号：US12822182

申请日：2010-06-24

申请人： Hao Meng ,  Peiqi Xuan

发明人： Hao Meng ,  Peiqi Xuan

IPC分类号： H04B1/18

CPC分类号： H03J5/244 ,  H03J2200/10

摘要： A system and method for sharing a switched capacitor array (SCA) by two tuning circuits are disclosed. In a multiple-band radio receiver, there is a need to use multiple tuning circuits for signals in different bands. The tuning circuit typically comprised an adjustable capacitance device and other tuning components, where the adjustable capacitance device is often implemented in SCA. The present invention discloses a system and method comprising n sections of capacitor elements where each capacitor element comprises a capacitor and switches to selectively connect the capacitor to one of the tuning circuit. Consequently, the SCA can be shared by the two tuning circuits. The control bits for the switched may be provided from a programmable control register.

摘要翻译： 公开了一种通过两个调谐电路共享开关电容阵列（SCA）的系统和方法。 在多频带无线电接收机中，需要对不同频段的信号使用多个调谐电路。 调谐电路通常包括可调电容器件和其他调谐组件，其中可调电容器件通常在SCA中实现。 本发明公开了一种包括电容器元件的n个部分的系统和方法，其中每个电容器元件包括一个电容器，并且开关将该电容器选择性地连接到一个调谐电路。 因此，SCA可以由两个调谐电路共享。 可以从可编程控制寄存器提供用于切换的控制位。

公开(公告)号：US08131229B1

公开(公告)日：2012-03-06

申请号：US12249725

申请日：2008-10-10

申请人： Robert Wilson ,  John B. Groe ,  Kenneth Scott Walley

发明人： Robert Wilson ,  John B. Groe ,  Kenneth Scott Walley

IPC分类号： H04B1/66 ,  H04K3/00

CPC分类号： H04L27/364

摘要： Apparatus and methods for adjustment of spectral signal characteristics in polar modulators are described. A composite signal detection circuit is configured to detect when a signal trajectory of a composite signal provided to the polar modulator passes near the origin of a complex plane associated with the composite signal, and then adjusts the composite signal to pass through the origin. A spectral adjustment circuit is described to adjust AM and FM or PM components of the composite signal to reduce the deviation of an FM component of the composite signal.

摘要翻译： 描述用于调节极性调制器中的频谱信号特性的装置和方法。 复合信号检测电路被配置为检测提供给极性调制器的复合信号的信号轨迹何时通过与复合信号相关联的复平面的原点，然后调整复合信号以通过原点。 描述了一个频谱调节电路来调整复合信号的AM和FM或PM分量，以减少复合信号的FM分量的偏差。

公开(公告)号：US08111776B1

公开(公告)日：2012-02-07

申请号：US12119279

申请日：2008-05-12

申请人： James A. Crawford

发明人： James A. Crawford

IPC分类号： H04L27/00

CPC分类号： H04L27/361

摘要： Systems and methods for bandwidth reduction in polar modulation systems are described. Detection of problematic signal transition paths may performed, and then, dependent on the signal path, a correction signal may be generated and added to the signal to improve system performance. In typical implementations, detection of problematic signal paths may be performed by determining whether the signal transitions through a particular region in the signal constellation, such as a region about the origin, or whether the signal instantaneous frequency exceeds a predetermined threshold, and then responsively generating the correction signal.

摘要翻译： 描述了极化调制系统中带宽降低的系统和方法。 可以执行有问题的信号转换路径的检测，然后，取决于信号路径，可以产生校正信号并将其加到信号上以提高系统性能。 在典型的实现中，可以通过确定信号是否过渡到信号星座中的特定区域，例如关于原点的区域，或者信号瞬时频率是否超过预定阈值，然后响应地产生 校正信号。

公开(公告)号：US20120025921A1

公开(公告)日：2012-02-02

申请号：US12893280

申请日：2010-09-29

申请人： Yu Yang ,  Xuechu Li ,  Peiqi Xuan

发明人： Yu Yang ,  Xuechu Li ,  Peiqi Xuan

IPC分类号： H03B5/12

CPC分类号： H03B5/1228 ,  H03B5/1212 ,  H03B5/1243 ,  H03B2200/0062

摘要： A low noise VCO circuit for an LC VCO circuit comprising MOS varactors is disclosed. The LC VCO circuit usually comprises an LC tuning circuit coupled with a pair of cross-coupled transistors used as a negative impedance element. A pair of varactors is used to provide fine tuning by applying a control voltage to the varactor. Since the varactor is also coupled to the pair of cross-coupled transistor, the process variation and temperature change may affect the bias voltage coupled to the pair of varactors. Therefore, a bias circuit usually is used to alleviate the impact of process variation and temperature change associated with the pair of transistor. Nevertheless, the bias voltage typically is implemented by providing a current flowing through a resistor, wherein the current is generated by a current source. The noise associated with the current source will affect the performance of the VCO circuit. A low noise VCO circuit is disclosed which utilizes a low noise bias circuit. The low noise bias circuit comprises a current source, a load device and a voltage divider wherein the load device is coupled to the voltage divider in parallel. The load device may be implemented using a bipolar transistor or a diode-connected MOS device.

摘要翻译： 公开了一种用于包括MOS可变电抗器的LC VCO电路的低噪声VCO电路。 LC VCO电路通常包括与用作负阻抗元件的一对交叉耦合晶体管耦合的LC调谐电路。 一对变容二极管用于通过对变容二极管施加控制电压来提供微调。 由于变容二极管还耦合到一对交叉耦合晶体管，所以工艺变化和温度变化可能影响耦合到该对变容二极管的偏置电压。 因此，偏置电路通常用于减轻与该对晶体管相关的工艺变化和温度变化的影响。 然而，偏置电压通常通过提供流过电阻器的电流来实现，其中电流由电流源产生。 与电流源相关的噪声将影响VCO电路的性能。 公开了一种利用低噪声偏置电路的低噪声VCO电路。 低噪声偏置电路包括电流源，负载装置和分压器，其中负载装置并联耦合到分压器。 负载装置可以使用双极晶体管或二极管连接的MOS器件来实现。

公开(公告)号：US08712354B2

公开(公告)日：2014-04-29

申请号：US13485907

申请日：2012-05-31

申请人： Yifeng Zhang ,  Tracey Lee Chavers ,  Peiqi Xuan ,  Qifa Wu

发明人： Yifeng Zhang ,  Tracey Lee Chavers ,  Peiqi Xuan ,  Qifa Wu

IPC分类号： H04B1/18 ,  H04B7/00 ,  H04W4/00 ,  H04W72/00

CPC分类号： H04B1/034 ,  H03J1/0091

摘要： FM radio transmitter is being widely used in portable devices as a convenient way to output audio contents to ubiquitously available FM radio receivers in cars or homes. However, the signal from the FM radio transmitter may be interfering with the signal being broadcast by an FM radio station. A scan system is incorporated into the FM radio transmitter to quickly and reliably identify a vacant channel for the FM radio transmitter to use. The scan system measures on-channel and out-of-channel signal quality and selects a best channel for transmission based on the measured on-channel and out-of-channel signal quality. The scan system is also incorporated into an FM radio receiver to quickly and reliably tune to a valid channel. The scan system selects the valid channel based on the measured on-channel and out-of-channel signal quality.

摘要翻译： FM无线电发射机正在便携式设备中广泛使用，以便将音频内容输出到汽车或家庭中普遍可用的FM无线电接收机。 然而，来自FM无线电发射机的信号可能干扰由FM无线电台广播的信号。 扫描系统被并入FM无线电发射机，以快速可靠地识别用于FM无线电发射机使用的空闲信道。 扫描系统测量通道和通道外信号质量，并根据测量的通道和通道外信号质量选择最佳传输通道。 扫描系统也被并入到FM无线电接收机中以快速可靠地调谐到有效信道。 扫描系统基于所测量的在线信道和信道外信号质量来选择有效信道。

公开(公告)号：US08280330B2

公开(公告)日：2012-10-02

申请号：US12649345

申请日：2009-12-30

申请人： Peiqi Xuan ,  Yifeng Zhang

发明人： Peiqi Xuan ,  Yifeng Zhang

IPC分类号： H04B1/06 ,  H04B7/00 ,  H04B1/18

CPC分类号： H03L7/22 ,  H03L7/0805 ,  H03L7/0991 ,  H03L7/10 ,  H03L7/183

摘要： Systems and methods of clock generation for radio frequency receiver. In radio frequency receiver, the system requires accurate local oscillating (LO) signal and system clocks for proper operation and to ensure high quality performance. In order to achieve accurate LO frequency and system clock, a crystal or and accurate reference clock is provide to the clock generation circuit. How a low-cost receiver, it is desirable to eliminate the requirement for a crystal or an accurate reference clock. The present invention discloses systems and methods to utilize a pilot signal embedded in the transmitted signal. The pilot signal usually has very accurate frequency which is particular true for broadcast system such as FM broadcast. In various embodiments of the present invention, the systems and methods measure the relation between the frequency of the pilot signal and the current clock generated. The measured result is compared with a know relation corresponding to the frequency of the pilot signal and the target clock signal and the result is used to adjust the clock generation circuit.

摘要翻译： 无线电频率接收机的时钟发生系统和方法。 在射频接收机中，系统需要精确的本地振荡（LO）信号和系统时钟，以便正常运行，并确保高质量的性能。 为了实现准确的LO频率和系统时钟，提供晶体或精确的参考时钟给时钟发生电路。 低成本接收机如何消除晶体或精确参考时钟的要求。 本发明公开了利用嵌入发射信号中的导频信号的系统和方法。 导频信号通常具有非常精确的频率，这对于诸如FM广播的广播系统尤其如此。 在本发明的各种实施例中，系统和方法测量导频信号的频率与所产生的当前时钟之间的关系。 将测量结果与对应于导频信号和目标时钟信号的频率的已知关系进行比较，并将结果用于调整时钟产生电路。