公开(公告)号：US07962113B2

公开(公告)日：2011-06-14

申请号：US11263280

申请日：2005-10-31

申请人： Li Gao ,  Richard A Johnson ,  James M. Nohrden

发明人： Li Gao ,  Richard A Johnson ,  James M. Nohrden

IPC分类号： H04B1/10

CPC分类号： H04B1/30

摘要： In one embodiment, a method provides multiple-tone wideband I/Q mismatch calibration. A plurality of calibration frequencies is selected within a channel. A calibration tone is applied to the channel at each of the plurality of calibration frequencies. An I/Q mismatch is estimated at each of the plurality of calibration frequencies. An n-th order filter is constructed to compensate received signals relative to the estimated I/Q mismatch related to each calibration frequency.

摘要翻译： 在一个实施例中，一种方法提供多音宽度I / Q失配校准。 在通道内选择多个校准频率。 在多个校准频率中的每一个处，校准音被施加到通道。 在多个校准频率中的每一个处估计I / Q失配。 构造n阶滤波器来补偿相对于与每个校准频率相关的估计的I / Q失配的接收信号。

公开(公告)号：US07558546B2

公开(公告)日：2009-07-07

申请号：US11239991

申请日：2005-09-30

申请人： Richard A. Johnson ,  James M. Nohrden ,  Li Gao

发明人： Richard A. Johnson ,  James M. Nohrden ,  Li Gao

IPC分类号： H04B1/18

CPC分类号： H03D7/166

摘要： A method in which one of a high-side mix mode and a low-side mix mode is selected in response to an interference characteristic of a desired channel of a radio frequency (RF) input signal is disclosed. In the high-side mix mode, a direct digital frequency synthesizer (130) is initialized to output a digital local oscillator signal at a first frequency suitable for performing a high-side mix of the desired channel to an intermediate frequency (IF). In the low-side mix mode, the direct digital frequency synthesizer (130) is initialized to output the digital local oscillator signal at a second frequency suitable for performing a low-side mix of the desired channel to said IF. The RF input signal is mixed with the digital local oscillator signal to provide an IF output signal at the IF.

摘要翻译： 公开了响应于射频（RF）输入信号的期望信道的干扰特性来选择高侧混合模式和低侧混合模式之一的方法。 在高侧混合模式中，直接数字频率合成器（130）被初始化，以便将第一频率的数字本地振荡器信号输出到适于执行期望信道的高侧混频到中频（IF）。 在低侧混合模式中，直接数字频率合成器（130）被初始化，以便以适于执行期望信道的低端混合的所述IF的第二频率输出数字本地振荡器信号。 RF输入信号与数字本地振荡器信号混合，以在IF提供IF输出信号。

公开(公告)号：US07443911B2

公开(公告)日：2008-10-28

申请号：US10875863

申请日：2004-06-24

申请人： Shahram Tadayyon ,  James M. Nohrden ,  James Ting-Yu Kao

发明人： Shahram Tadayyon ,  James M. Nohrden ,  James Ting-Yu Kao

IPC分类号： H04B1/38

CPC分类号： H04L12/2801 ,  H04N21/4382 ,  H04N21/4383

摘要： According to one embodiment of the present invention, a device may receive one of multiple frequencies at a clock input of the device; determine which of the multiple frequencies is received; and generate at least one internal clock frequency for operation of the device using the received frequency. For example, such a device may be embedded within a system having a receiver to receive a satellite signal spectrum and to tune a signal channel and baseband circuitry coupled to the receiver to process digital data corresponding to the signal channel, where the baseband circuitry operates at the frequency provided to the device.

摘要翻译： 根据本发明的一个实施例，设备可以在设备的时钟输入处接收多个频率中的一个; 确定接收多个频率中的哪一个; 并且使用接收到的频率生成至少一个内部时钟频率以用于设备的操作。 例如，这样的设备可以嵌入在具有接收器的系统中，以接收卫星信号频谱并且调谐耦合到接收机的信号信道和基带电路以处理对应于信号信道的数字数据，其中基带电路在 提供给设备的频率。

公开(公告)号：US07675996B2

公开(公告)日：2010-03-09

申请号：US11194034

申请日：2005-07-29

申请人： Richard A. Johnson ,  James M. Nohrden ,  Scott T. Dupuie ,  Andrew W. Dornbusch

发明人： Richard A. Johnson ,  James M. Nohrden ,  Scott T. Dupuie ,  Andrew W. Dornbusch

IPC分类号： H03K9/00 ,  H04L27/00

CPC分类号： H03J1/0008 ,  H03D7/00 ,  H04B1/0007 ,  H04B1/28 ,  H04B15/04 ,  H04B2215/064 ,  H04B2215/065 ,  H04N5/4446 ,  H04N5/46 ,  H04N21/4263 ,  H04N21/4305

摘要： A receiver (1100) includes a direct digital frequency synthesizer (130), a mixer (105), and a clock source (1110, 1130). The direct digital frequency synthesizer has an input terminal for receiving a first clock signal at a first frequency, and an output terminal for providing a digital local oscillator signal synchronously with the first clock signal. The mixer (105) has a first input terminal for receiving a radio frequency (RF) signal, a second input terminal coupled to the output terminal of the direct digital frequency synthesizer (130), and an output terminal for providing an IF signal having a spectrum centered about a selectable one of a plurality of center frequencies. The clock source (1110, 1130) has an output terminal for providing the first clock signal without using a harmonic frequency that overlaps the spectrum for the plurality of center frequencies.

摘要翻译： 接收器（1100）包括直接数字频率合成器（130），混频器（105）和时钟源（1110,1130）。 直接数字频率合成器具有用于以第一频率接收第一时钟信号的输入端子和用于与第一时钟信号同步地提供数字本地振荡器信号的输出端子。 混频器（105）具有用于接收射频（RF）信号的第一输入端，耦合到直接数字频率合成器（130）的输出端的第二输入端，以及用于提供IF信号的输出端， 频谱以多个中心频率中的可选择的一个为中心。 时钟源（1110,1130）具有用于提供第一时钟信号的输出端，而不使用与多个中心频率的频谱重叠的谐波频率。

公开(公告)号：US07142255B2

公开(公告)日：2006-11-28

申请号：US10681011

申请日：2003-10-08

申请人： James M. Nohrden

发明人： James M. Nohrden

IPC分类号： H04N5/44 ,  H04N5/445

CPC分类号： H04N21/466 ,  H04N5/4401 ,  H04N5/50 ,  H04N21/4263 ,  H04N21/4331 ,  H04N21/434 ,  H04N21/4383 ,  H04N21/4384 ,  H04N21/44209 ,  H04N21/44222

摘要： A transport stream and channel selection system for digital video transmissions and associated method are disclosed that use predictive analyses to tune additional digital transport streams that contain desirable or optimal groupings of multiplexed channels. An analysis is made of which channels are multiplexed together at any given time to determine which transport streams provide a desirable and/or optimal combination of multiplexed channels, and a wide variety of information and algorithms can be used in determining the transport streams and channels to select. Thus, in addition to having available the channels multiplexed with the currently selected channel, a plurality of other channels multiplexed together in additional digital transport streams are made available for pre-processing. As such, the available channels for use in providing predictive pre-selection and for use in reducing delay experienced by a user in changing channels are greatly enhanced.

摘要翻译： 公开了用于数字视频传输和相关方法的传输流和信道选择系统，其使用预测分析来调整包含多路复用信道的期望或最佳分组的附加数字传输流。 分析哪些信道在任何给定时间被多路复用在一起以确定哪些传输流提供多路复用信道的期望和/或最优组合，并且可以使用各种各样的信息和算法来确定传输流和信道 选择。 因此，除了具有与当前选择的信道复用的信道的可用性之外，使得在附加数字传输流中多路复用的多个其它信道可用于预处理。 因此，用于提供预测预选和用于减少用户在改变频道中经历的延迟的可用信道被大大增强。

公开(公告)号：US06944301B1

公开(公告)日：2005-09-13

申请号：US09265659

申请日：1999-03-10

申请人： James M. Nohrden ,  Brian D. Green ,  Brian P. Lum Shue Chan

发明人： James M. Nohrden ,  Brian D. Green ,  Brian P. Lum Shue Chan

IPC分类号： H04B1/00 ,  H04B1/10 ,  H04B17/00 ,  H04H20/47 ,  H04H5/00

CPC分类号： H04H20/47

摘要： Distortion discrimination circuitry for digital radio receivers and corresponding methods are disclosed that accurately and efficiently discriminate distortion events, including impulse noise and multipath distortion events, to improve the quality of audio output signals. The distortion discrimination circuitry monitors and analyzes the demodulator output to determine when a distortion event has occurred and provides an appropriate indication signal for use by other circuitry within the radio receiver. More particularly, the distortion discrimination circuitry includes impulse noise circuitry that looks for high frequency noise in both the magnitude and multiplexed outputs of the demodulator to determine the occurrence of impulse noise distortion events. The distortion discrimination circuitry also includes multipath circuitry that looks for a drop-off in signal power between the multiplexed output of the demodulator and a moving average version of that same signal to determine the occurrence of multipath distortion events. In addition, stereo decoder circuitry modifies the audio output signals in response to indications of distortion events.

摘要翻译： 公开了用于数字无线电接收机的失真鉴别电路和相应的方法，其精确和有效地区分包括脉冲噪声和多径失真事件在内的失真事件，以提高音频输出信号的质量。 失真识别电路监视和分析解调器输出以确定失真事件何时发生，并提供适当的指示信号供无线电接收机内的其他电路使用。 更具体地，失真识别电路包括在解调器的幅度和复用输出中寻找高频噪声以确定脉冲噪声失真事件的出现的脉冲噪声电路。 失真识别电路还包括多路径电路，其寻找解调器的多路复用输出与该相同信号的移动平均版本之间的信号功率的下降以确定多径失真事件的发生。 此外，立体声解码器电路响应于失真事件的指示来修改音频输出信号。

公开(公告)号：US07995981B2

公开(公告)日：2011-08-09

申请号：US11263279

申请日：2005-10-31

申请人： Li Gao ,  Richard A Johnson ,  James M. Nohrden

发明人： Li Gao ,  Richard A Johnson ,  James M. Nohrden

IPC分类号： H04B1/10

CPC分类号： H04B1/123

摘要： In one embodiment, a method is provided. An in-band calibration tone is generated at a frequency of an undesired interfering signal. A receiver is calibrated using the calibration tone to reject image interference caused by the undesired interfering signal.

摘要翻译： 在一个实施例中，提供了一种方法。 在不期望的干扰信号的频率处产生带内校准音。 使用校准音来校准接收机，以抑制由不需要的干扰信号引起的图像干扰。

公开(公告)号：US06389270B1

公开(公告)日：2002-05-14

申请号：US09266418

申请日：1999-03-10

申请人： James M. Nohrden ,  Brian P. Lum Shue Chan

发明人： James M. Nohrden ,  Brian P. Lum Shue Chan

IPC分类号： H04B118

CPC分类号： H03J1/0091 ,  H03J1/0066

摘要： Station scan circuitry for a radio-frequency receiver and corresponding methods are disclosed that efficiently determine the presence of a station on available channels. The station scan circuitry includes circuitry that determines if the signal power on a given channel exceeds a threshold value. Additional circuitry compares the channel signal strength and the adjacent channel signal to determine if a ratio of the two exceeds a threshold level. If both the signal power and the signal strength ratio are sufficient, the station scan circuitry indicates that a station has been found. To make the signal strength comparison, the station scan circuitry includes circuitry for determining a post-filter signal strength and a pre-filter signal strength for the received signal.

摘要翻译： 公开了用于射频接收机的站扫描电路和相应的方法，其有效地确定站在可用信道上的存在。 站扫描电路包括确定给定信道上的信号功率是否超过阈值的电路。 附加电路比较信道信号强度和相邻信道信号，以确定两者的比值是否超过阈值水平。 如果信号功率和信号强度比都足够，则站扫描电路指示已经找到站。 为了进行信号强度比较，站扫描电路包括用于确定接收信号的后置滤波器信号强度和预滤波器信号强度的电路。