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公开(公告)号：US08036622B2
公开(公告)日：2011-10-11
申请号：US11341184
申请日：2006-01-28
CPC分类号： H03D3/008
摘要： Techniques for cancelling DC offset are described. A DC offset cancellation circuit in a receiver cancels DC offsets caused by leaked LO (local oscillator) signals from a LO signal generator. The receiver first calibrates itself by using the DC offset cancellation circuit during a transmit mode. During the calibration, the DC offset cancellation circuit stores the DC offset voltage signal caused by the leaked LO signals. During a receiving mode when the receiver is receiving a signal, the receiver subtracts the stored DC offset voltage signal from the received signal to cancel the DC offsets caused by leaked LO signals.
摘要翻译： 描述了消除DC偏移的技术。 接收器中的DC偏移消除电路消除由LO信号发生器泄漏的LO（本地振荡器）信号引起的DC偏移。 接收机首先通过在发送模式期间使用DC偏移消除电路进行自校准。 在校准期间，DC偏移消除电路存储由泄露的LO信号引起的DC偏移电压信号。 在接收器接收信号的接收模式期间，接收机从接收信号中减去存储的直流失调电压信号，以消除由泄露的LO信号引起的直流偏移。
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公开(公告)号：US20070072571A1
公开(公告)日：2007-03-29
申请号：US11341184
申请日：2006-01-28
申请人： Runhua Sun , Christian Holenstein , James Jaffee
发明人： Runhua Sun , Christian Holenstein , James Jaffee
CPC分类号： H03D3/008
摘要： Techniques for cancelling DC offset are described. A DC offset cancellation circuit in a receiver cancels DC offsets caused by leaked LO (local oscillator) signals from a LO signal generator. The receiver first calibrates itself by using the DC offset cancellation circuit during a transmit mode. During the calibration, the DC offset cancellation circuit stores the DC offset voltage signal caused by the leaked LO signals. During a receiving mode when the receiver is receiving a signal, the receiver subtracts the stored DC offset voltage signal from the received signal to cancel the DC offsets caused by leaked LO signals.
摘要翻译： 描述了消除DC偏移的技术。 接收器中的DC偏移消除电路消除由LO信号发生器泄漏的LO（本地振荡器）信号引起的DC偏移。 接收机首先通过在发送模式期间使用DC偏移消除电路进行自校准。 在校准期间，DC偏移消除电路存储由泄露的LO信号引起的DC偏移电压信号。 在接收器接收信号的接收模式期间，接收机从接收信号中减去存储的直流失调电压信号，以消除由泄露的LO信号引起的直流偏移。
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公开(公告)号：US20070058750A1
公开(公告)日：2007-03-15
申请号：US11228090
申请日：2005-09-15
申请人： Puay Hoe See , Gary Ballantyne , James Jaffee , Gurkanwal Sahota
发明人： Puay Hoe See , Gary Ballantyne , James Jaffee , Gurkanwal Sahota
CPC分类号： H04L27/361 , H03C3/0966 , H03C3/0983
摘要： A phase modulator faithfully reproduces higher frequency modulation using an offset phase-locked loop (OPLL) without passing excessive noise through an increased bandwidth of the OPLL. A quadrature modulator modulates information from a baseband signal onto a passband IF signal and, after a limiter strips away amplitude variations, the OPLL reproduces the phase modulation on an RF signal. The OPLL introduces a group delay that does not vary linearly with the modulation frequency and that consequently causes distortion when uncompensated. A baseband filter filters the amplitude of the baseband signal and introduces a complementary group delay that compensates for the OPLL group delay and results in a combined group delay of the baseband filter, quadrature modulator, limiter and OPLL that remains substantially constant as modulation frequency varies. Compensating for the OPLL group delay reduces distortion and the spectral energy at offset frequencies from the carrier frequency of the RF signal.
摘要翻译： 相位调制器使用偏移锁相环（OPLL）忠实地再现更高的频率调制，而不会通过OPLL的带宽增加而过多的噪声。 正交调制器将信号从基带信号调制到通带IF信号上，并且在限幅器剥离幅度变化之后，OPLL再现RF信号上的相位调制。 OPLL引入了不随调制频率线性变化的群延迟，从而导致无补偿时的失真。 基带滤波器对基带信号的幅度进行滤波，并引入补偿组延迟，补偿OPLL组延迟，并导致基带滤波器，正交调制器，限幅器和OPLL的组合群延迟，其随调制频率变化而保持基本恒定。 补偿OPLL组延迟可以减少偏移频率下的失真和频谱能量与RF信号的载波频率。
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公开(公告)号：US07415088B2
公开(公告)日：2008-08-19
申请号：US10123841
申请日：2002-04-15
IPC分类号： H04L7/00
CPC分类号： H04B1/16
摘要： Techniques for processing incoming signals conforming to a plurality of standards or communication formats with a single baseband receive section are disclosed. In one aspect, a plurality of analog processing components are adjusted in response to a format select signal, set according to one of a plurality of supported formats or standards. In another aspect, the operating mode of an A/D converter is tuned in response to the format select signal. In yet another aspect, the response characteristics of a jammer filter are tuned in response to the format select signal. In yet another aspect, the adjustment of the plurality of analog processing components is carried out by varying the frequency of a sample clock in response to the format select signal. Various other aspects are also presented. These aspects have the benefit of allowing a single baseband receive section to be deployed to process analog signals conforming to a plurality of communications standards or formats, in a power and area efficient manner.
摘要翻译： 公开了用于处理符合多个标准或与单个基带接收部分的通信格式的输入信号的技术。 在一个方面，响应于根据多种支持的格式或标准之一设置的格式选择信号来调整多个模拟处理组件。 在另一方面，响应于格式选择信号来调整A / D转换器的工作模式。 在另一方面，响应于格式选择信号来调谐干扰滤波器的响应特性。 在另一方面，通过响应于格式选择信号改变采样时钟的频率来执行多个模拟处理组件的调整。 还提出了各种其他方面。 这些方面的好处是允许单个基带接收部分以功率和区域有效的方式被部署来处理符合多个通信标准或格式的模拟信号。
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公开(公告)号：US07548593B2
公开(公告)日：2009-06-16
申请号：US11228090
申请日：2005-09-15
IPC分类号： H03C3/00
CPC分类号： H04L27/361 , H03C3/0966 , H03C3/0983
摘要： A phase modulator faithfully reproduces higher frequency modulation using an offset phase-locked loop (OPLL) without passing excessive noise through an increased bandwidth of the OPLL. A quadrature modulator modulates information from a baseband signal onto a passband IF signal and, after a limiter strips away amplitude variations, the OPLL reproduces the phase modulation on an RF signal. The OPLL introduces a group delay that does not vary linearly with the modulation frequency and that consequently causes distortion when uncompensated. A baseband filter filters the amplitude of the baseband signal and introduces a complementary group delay that compensates for the OPLL group delay and results in a combined group delay of the baseband filter, quadrature modulator, limiter and OPLL that remains substantially constant as modulation frequency varies. Compensating for the OPLL group delay reduces distortion and the spectral energy at offset frequencies from the carrier frequency of the RF signal.
摘要翻译： 相位调制器使用偏移锁相环（OPLL）忠实地再现更高的频率调制，而不会通过OPLL的带宽增加而过多的噪声。 正交调制器将信号从基带信号调制到通带IF信号上，并且在限幅器剥离幅度变化之后，OPLL再现RF信号上的相位调制。 OPLL引入了不随调制频率线性变化的群延迟，从而导致无补偿时的失真。 基带滤波器对基带信号的幅度进行滤波，并引入补偿组延迟，补偿OPLL组延迟，并导致基带滤波器，正交调制器，限幅器和OPLL的组合群延迟，其随调制频率变化而保持基本恒定。 补偿OPLL组延迟可以减少偏移频率下的失真和频谱能量与RF信号的载波频率。
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6.发明授权Wireless communications transceiver: transmitter using a harmonic rejection mixer and an RF output offset phase-locked loop in a two-step up-conversion architecture and receiver using direct conversion architecture 有权无线通信收发器：使用谐波抑制混频器的发射机和使用直接转换架构的两级上转换架构和接收机中的RF输出偏移锁相环公开(公告)号：US07167686B2
公开(公告)日：2007-01-23
申请号：US10350407
申请日：2003-01-24
IPC分类号： H04B1/40
CPC分类号： H03C3/0966 , H03C3/40 , H03D7/18 , H03D2200/0086 , H03L7/18 , H04B1/403
摘要： A wireless transceiver includes a transmitter having a harmonic rejection mixer and an RF output phase-locked loop in a two step up-conversion architecture, and a direct conversion receiver. The transmitter includes a local oscillator for producing a signal at a multiple of an intermediate frequency, a quadrature modulator harmonic rejection mixer responsive to the signal at the multiple of the intermediate frequency for modulating in-phase and quadrature-phase base-band signals to produce an intermediate frequency signal, a filter responsive to the intermediate frequency signal for producing a filtered intermediate frequency signal, and an RF output offset phase-locked loop responsive to the filtered intermediate frequency signal and the signal at the multiple of the intermediate frequency for producing an RF transmission signal. The harmonic rejection mixer reduces filtering requirements to facilitate a high level of circuit integration. The local oscillator may use a integer or fractional-N phase-locked loop.
摘要翻译： 无线收发器包括具有谐波抑制混频器的发射器和两级升压转换架构中的RF输出锁相环以及直接转换接收器。 发射机包括用于产生中频倍数的信号的本地振荡器，响应于中频倍数处的信号的正交调制器谐波抑制混频器，用于调制同相和正交相位基带信号以产生 中频信号，响应于用于产生滤波后的中频信号的中频信号的滤波器，以及响应于滤波的中频信号的RF输出偏移锁相环以及中频倍数的信号，以产生 RF传输信号。 谐波抑制混频器降低了滤波要求，以促进高水平的电路集成。 本地振荡器可以使用整数或分数N锁相环。
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公开(公告)号：US07130599B2
公开(公告)日：2006-10-31
申请号：US09798378
申请日：2001-03-02
IPC分类号： H03J7/32
摘要： In an exemplary application, an apparatus according to a disclosed embodiment receives a radio frequency signal and outputs an intermediate frequency signal. Rejection of image components in the intermediate frequency signal is obtained without the need to preprocess the radio frequency signal with an image reject filter. Such an apparatus may also exhibit an image rejection performance that is robust to frequency deviation of a local oscillator.
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