公开(公告)号：US06630861B2

公开(公告)日：2003-10-07

申请号：US09962179

申请日：2001-09-25

申请人： Yoshizumi Kawaoka

发明人： Yoshizumi Kawaoka

IPC分类号： H03G516

CPC分类号： H03F1/342 ,  H03G1/007

摘要： A variable gain amplifier includes at least two amplifiers for amplifying a signal, the at least two amplifiers being connected in series with one another, and a variable resistor having a resistance that is controlled in accordance with a voltage applied to a control terminal, the variable resistor being connected between the outputs of two of the at least two amplifiers having opposite output phases. As a result, the variable gain amplifier is capable of a low-gain operation and an attenuating operation in a high-frequency amplifier used in a communications device for transmitting and receiving high-frequency signals.

公开(公告)号：US06333675B1

公开(公告)日：2001-12-25

申请号：US09543893

申请日：2000-04-06

申请人： Shinji Saito

发明人： Shinji Saito

IPC分类号： H03G516

CPC分类号： H03G3/3042

摘要： A variable gain amplifier includes multiple unit variable gain amplifiers connected in series which amplify an input signal in accordance with their respective gains and generate a multi-stage amplified signal. A gain control circuit generates voltage control signals, one for each of the unit amplifiers, from a gain control input signal. The control signals control the respective gains of the unit amplifiers such that the gain of the first amplifier in the series is greater than the gain of the last amplifier in the series.

摘要翻译： 可变增益放大器包括串联连接的多个单位可变增益放大器，其根据其相应的增益放大输入信号，并产生多级放大信号。 增益控制电路从增益控制输入信号生成针对每个单位放大器的电压控制信号。 控制信号控制单元放大器的相应增益，使得串联中的第一放大器的增益大于串联中的最后一个放大器的增益。

公开(公告)号：US06525606B1

公开(公告)日：2003-02-25

申请号：US09815698

申请日：2001-03-21

申请人： Simon Atkinson

发明人： Simon Atkinson

IPC分类号： H03G516

CPC分类号： H03G7/06

摘要： A variable gain amplifier system for radio frequency signals is disclosed. The system provides a relatively constant gain change in decibels responsive to an incremental change in control voltage. The system includes two or more cascaded gain stage amplifiers. Each gain stage amplifier is adjustable between a first gain setting and a second gain setting.

摘要翻译： 公开了一种用于射频信号的可变增益放大器系统。 响应于控制电压的增量变化，该系统提供相对恒定的分贝增益变化。 该系统包括两个或多个级联增益级放大器。 每个增益级放大器可在第一增益设置和第二增益设置之间调节。

公开(公告)号：US06472937B1

公开(公告)日：2002-10-29

申请号：US09715871

申请日：2000-11-15

申请人： Michael L. Gerard ,  Terry J. Shie ,  Philip H. Thompson

发明人： Michael L. Gerard ,  Terry J. Shie ,  Philip H. Thompson

IPC分类号： H03G516

CPC分类号： H03G3/3042 ,  H03F1/302 ,  H03F3/3432

摘要： The invention includes an amplifier and a biasing circuit. The amplifier may have one or more driver stages and a final stage. Each stage may be connected in series to pass along and amplify an input signal from one stage to the next. The input signal level may increase over time. The biasing circuit may include a voltage follower having an output and a reference transistor. Each stage may include a transistor having a base that is connected to the output of the voltage follower. A resistor may be placed between each transistor stage base and the output of the voltage follower. The base of the final stage transistor may be DC connected to the reference transistor base. In operation, the reference transistor collector current and thus the final stage base bias voltage may be maintained at fixed level by feedback through the voltage follower. However, the base bias current of the final stage and, thus, the voltage drop across the final stage base bias resistor and the voltage follower output voltage may increase with the input signal level. The increase in the voltage follower output voltage, in turn, may increase the base bias voltage of one or more driver stages. The increase of the base bias voltage of a driver stage as a function of an increase in the input signal level may extend the amplifier gain compression point to a higher output power level.

摘要翻译： 本发明包括放大器和偏置电路。 放大器可以具有一个或多个驱动器级和最后级。 每个级可以串联连接，以便将输入信号从一级放大到下一级。 输入信号电平随时间而增加。 偏置电路可以包括具有输出和参考晶体管的电压跟随器。 每个级可以包括具有连接到电压跟随器的输出端的基极的晶体管。 每个晶体管级基极和电压跟随器的输出端之间可以放置电阻。 最后级晶体管的基极可以直流连接到参考晶体管基极。 在操作中，参考晶体管集电极电流和因此最终级基极偏置电压可以通过电压跟随器的反馈保持在固定电平。 然而，最终级的基极偏置电流以及因此最终级基极偏置电阻上的电压降和电压跟随器输出电压可能随输入信号电平而增加。 电压跟随器输出电压的增加又可能增加一个或多个驱动级的基极偏置电压。 作为输入信号电平的增加的函数的驱动器级的基极偏置电压的增加可以将放大器增益压缩点扩展到更高的输出功率电平。

公开(公告)号：US06828854B2

公开(公告)日：2004-12-07

申请号：US10745688

申请日：2003-12-29

申请人： Frank W. Singor ,  Arya R. Behzad

发明人： Frank W. Singor ,  Arya R. Behzad

IPC分类号： H03G516

CPC分类号： H03F3/45183 ,  H03F3/45381 ,  H03F3/45475 ,  H03F2200/516 ,  H03F2203/45392 ,  H03F2203/45651 ,  H03F2203/45652 ,  H03F2203/45682 ,  H03F2203/45696 ,  H03F2203/45702

摘要： A circuit and method for bridging an analog signal between two integrated circuits operating at different supply voltages. The circuit is a two stage fixed gain amplifier. The first stage is a transconductance amplifier and the second stage is an operational amplifier. The first stage converts an input signal from a voltage into a current. The second stage converts the current signal to an output voltage signal.

公开(公告)号：US06603351B2

公开(公告)日：2003-08-05

申请号：US09968559

申请日：2001-10-01

申请人： Yasuyuki Suzuki

发明人： Yasuyuki Suzuki

IPC分类号： H03G516

CPC分类号： H03F1/3205

摘要： A high-frequency power amplifier is provided, which suppresses effectively the distortion induced by gain deviation or fluctuation occurring in at least one of the amplifier stages without using the back-off of the operating point. The amplifier comprises first to n-th amplifier stages connected in cascade, where n is an integer greater than unity. A k-th one of the amplifier stages receives a k-th input signal power to produce a k-th output signal power, where k is an integer satisfying a relationship of 1≦k≦n. The k-th amplifier stage includes a transistor with an amplification function. The transistor has a gain change in a range of the k-th input signal power or the k-th output signal power. A m-th one of the amplifier stages receives a m-th output signal to produce a m-th output signal, where m is an integer satisfying a relationship of 1≦m≦n and m≠k. The m-th amplifier stage includes a transistor with an amplification function. The transistor has a gain change in a range of the m-th input signal power or the m-th output signal power. The gain change of the transistor of the m-th amplifier stage is decreased or cancelled by the gain change or the transistor of the k-th amplifier stage.

公开(公告)号：US06480063B2

公开(公告)日：2002-11-12

申请号：US09950751

申请日：2001-09-13

申请人： Masaki Ichihara

发明人： Masaki Ichihara

IPC分类号： H03G516

CPC分类号： H03G1/0088 ,  H03G3/3068

摘要： An object of the present invention is to suppress the generation of a transient voltage in the settings of gains of a plurality of variable gain amplifiers of a baseband circuit. A gain converting circuit provides a limiting value to the quantity of the change of a gain which can be changed once. If gain input data has large change and the gain change exceeding the limiting value is carried out, the quantity of the change is divided into a plurality of quantities of change equal to or lower than the limiting value and variable gain amplifiers are controlled to thereby realize a required gain change. A gain distribution circuit distributes gain control data to the respective variable gain amplifiers on the basis of gain output data of the gain converting circuit.

公开(公告)号：US06246285B1

公开(公告)日：2001-06-12

申请号：US09514644

申请日：2000-02-29

申请人： Osamu Nishikido

发明人： Osamu Nishikido

IPC分类号： H03G516

CPC分类号： H03G3/3042

摘要： In an automatic gain control (AGC) circuit based on a peak detection system having two filters, a voltage comparator selects one of two voltages and compares the selected voltage with a detection signal output from a wave detector. A second AGC filter selects a cut-off frequency based on the result of comparison of the voltage comparator and supplies a signal resulting from low-pass filtering, based on the selected cut-off frequency, to a voltage-controlled amplifier as a control voltage. When a highly modulated signal is abruptly input, selection of the cut-off frequency of the second AGC filter occurs.

摘要翻译： 在基于具有两个滤波器的峰值检测系统的自动增益控制（AGC）电路中，电压比较器选择两个电压中的一个，并将所选择的电压与从波检测器输出的检测信号进行比较。 第二AGC滤波器基于电压比较器的比较结果选择截止频率，并将基于选择的截止频率的低通滤波产生的信号作为控制电压提供给压控放大器 。 当高度调制的信号突然输入时，发生第二AGC滤波器的截止频率的选择。

公开(公告)号：US06236266B1

公开(公告)日：2001-05-22

申请号：US09444406

申请日：1999-11-22

申请人： Kenichiro Choumei ,  Kazutomi Mori ,  Akira Inoue ,  Toshio Okuda

发明人： Kenichiro Choumei ,  Kazutomi Mori ,  Akira Inoue ,  Toshio Okuda

IPC分类号： H03G516

CPC分类号： H03F1/302 ,  H03F3/19 ,  H03F3/72

摘要： A bias circuit and bias supply method for a multistage power amplifier including heterojunction bipolar transistors for power amplifying a high frequency signal and suppressing an increase in Rx noise during low power output operation of the multistage power amplifier. The bias circuit outputs a control signal Vapc from an external control circuit to the base of only a first-stage amplifier HBT in the multistage power amplifier. To the base of the second and each later power amplifying stage HBT of the multistage power amplifier, the bias circuit supplies a bias current regulated by voltage stabilizers according to the control signal Vapc.

摘要翻译： 一种用于多级功率放大器的偏置电路和偏置电源方法，包括用于功率放大高频信号的异质结双极晶体管，并抑制多级功率放大器的低功率输出操作期间的Rx噪声的增加。 偏置电路将控制信号Vapc从外部控制电路输出到仅在多级功率放大器中的第一级放大器HBT的基极。 对于多级功率放大器的第二和每个后续功率放大级HBT的基极，偏置电路根据控制信号Vapc提供由电压稳定器调节的偏置电流。

公开(公告)号：US06734730B2

公开(公告)日：2004-05-11

申请号：US10308003

申请日：2002-12-03

申请人： Takeshi Doi ,  Kenji Maio

发明人： Takeshi Doi ,  Kenji Maio

IPC分类号： H03G516

CPC分类号： H03G1/0088 ,  H03F3/72 ,  H03G3/3042

摘要： In order to provide a high sensitivity variable gain amplifier, there is provided a structure in which at least one path comprising at least a stage of the voltage-input/voltage-output amplifier+ a stage of voltage-input/current-output amplifier and a path comprising a stage of the voltage-input/current-output amplifier are connected in parallel between the input terminal and output terminal or, a structure in which a plurality of paths each comprising at least a stage of voltage-input/voltage-output amplifier+a stage of voltage-input/current-output amplifier are connected in parallel between the input terminal and output terminal. A gain is switched by selecting and operating any one of paths. When any one path is selected, an input impedance viewed from the input terminal is suppressed almost not to change or an output impedance viewed from the output terminal is suppressed almost not to change. Thereby, a high sensitivity wireless receiver can be realized.

摘要翻译： 为了提供高灵敏度可变增益放大器，提供了一种结构，其中至少一个路径包括电压输入/电压 - 输出放大器的至少一个级+电压输入/电流输出放大器的级和 包括电压输入/电流输出放大器的级的路径并联连接在输入端子和输出端子之间，或者其结构中，多个通路各自包括至少一级的电压输入/电压输出放大器 电压输入/电流输出放大器的一级在输入端子和输出端子之间并联连接。 通过选择和操作任何路径来切换增益。 当选择任何一个路径时，抑制从输入端子观察的输入阻抗几乎不变化，或者抑制从输出端子观察的输出阻抗几乎不改变。 因此，可以实现高灵敏度的无线接收器。