Amplifier circuit and method of controlling an amplifier for use in a
radio frequency communication system
    1.
    发明授权
    Amplifier circuit and method of controlling an amplifier for use in a radio frequency communication system 失效
    用于射频通信系统的放大器电路和控制放大器的方法

    公开(公告)号:US5623227A

    公开(公告)日:1997-04-22

    申请号:US544049

    申请日:1995-10-17

    IPC分类号: H03F1/32

    摘要: An amplifier circuit (100) for use in a radio frequency system. The circuit is comprised of a first amplifier (22) having a first input (20) receiving a first signal (16) and a first output (24). A first coupler (18) samples the first input (20) of the first amplifier (22) and a second coupler (26) samples the first output (24) of the first amplifier (22). A third coupler (36) then compares an output of the second coupler (28) and an output of the first coupler (34), producing an error signal (38) which is substantially indicative of the difference between the first input (20) and the first output (24). A fourth coupler (44) combines the error signal (38) with a second signal (48) to produce a composite signal (50), the second signal (48) at least partially correlated with the first signal (16) received by the first input (20) of the first amplifier. A second amplifier (52) is responsive to the composite signal (50) and produces a second output (54).

    摘要翻译: 一种用于射频系统的放大器电路(100)。 电路包括具有接收第一信号(16)和第一输出(24)的第一输入(20)的第一放大器(22)。 第一耦合器(18)对第一放大器(22)的第一输入端(20)进行采样,第二耦合器(26)采样第一放大器(22)的第一输出端(24)。 第三耦合器(36)然后比较第二耦合器(28)的输出和第一耦合器(34)的输出,产生误差信号(38),该误差信号基本上指示第一输入端(20)和 第一个输出(24)。 第四耦合器(44)将误差信号(38)与第二信号(48)组合以产生复合信号(50),所述第二信号(48)至少部分地与第一信号(48)接收的第一信号 第一放大器的输入(20)。 第二放大器(52)响应于复合信号(50)并产生第二输出(54)。

    Digital baseband receiver in a multi-carrier power amplifier
    4.
    发明授权
    Digital baseband receiver in a multi-carrier power amplifier 失效
    数字基带接收机在多载波功率放大器中

    公开(公告)号:US06829471B2

    公开(公告)日:2004-12-07

    申请号:US10091756

    申请日:2002-03-06

    IPC分类号: H04B116

    CPC分类号: H03F1/3235 H04B1/123

    摘要: A power amplifier system and method for locating carrier frequencies across a frequency band, identifying the modulation format of each carrier, and locating and suppressing undesired intermodulation distortion (IMD) products generated by the power amplifier. The system includes an amplifier for amplifying RF carrier signals in a main signal path, a variable phase shifter and variable attenuator on a feed forward path, and a tunable receiver that digitizes a portion of the frequency band to baseband. The tunable receiver includes a tunable voltage controlled oscillator which provides an oscillating frequency to a mixer and is phase-locked to a highly stable reference oscillator. The mixer downconverts a desired RF based on the oscillating frequency to IF. A filter passes only a selected portion of the IF signals, and the filter has a passband sufficient to discern both narrowband and wideband carriers and their associated IMD products. Based on the locations of the carrier frequencies, a processing unit determines the IMD locations of the carrier frequencies, determines the IMD locations, and adjusts the variable phase shifter and variable attenuator on the feed forward path until the IMD products in the main signal path are suppressed below a desired threshold.

    摘要翻译: 一种用于定位频带上的载波频率的功率放大器系统和方法,识别每个载波的调制格式,以及定位和抑制由功率放大器产生的不期望的互调失真(IMD)产物。 该系统包括用于放大主信号路径中的RF载波信号的放大器,前馈路径上的可变移相器和可变衰减器,以及将频带的一部分数字化为基带的可调谐接收器。 可调谐接收器包括可调谐压控振荡器,其将振荡频率提供给混频器,并且被锁相到高度稳定的参考振荡器。 混频器将基于振荡频率的所需RF降频到IF。 滤波器仅通过IF信号的选定部分,并且滤波器具有足以识别窄带和宽带载波及其相关IMD产物的通带。 基于载波频率的位置,处理单元确定载波频率的IMD位置,确定IMD位置,并且调整前馈路径上的可变移相器和可变衰减器,直到主信号路径中的IMD乘积为 抑制在所需阈值以下。